Jump to content

Sustainer Ideas


psw

Recommended Posts

Did i have connect Bridge mic and amp jack to left input in circuit?.

Yes...basically this circuit takes a signal from the guitars bridge pickup, amplifies it and send it to the speaker. Additionally, the signal gos to the amplifier as normal to the guitar amplifier so you can hear it, not through it!

I tested right output with speaker and it's works! rolleyes.gif. When i testing with driver and hold it above strings it works (the strings will vibrate).

Ok...so now we have a working sustainer!

Perhaps a pic of the actual guitar set up might help.

The intention is that this thing should be quiet. Distortions and squeal like feedback (EMI or electromagnetic interferance) is the usual problem. Problems of humming may simply be caused by a lack of proper wiring and shielding in the connections. For instance, if you are actually holding wires to a guitar lead, not a shielded cable for the inputs, long leads or other "testing" set ups, then hum would be expected and distortions, compressors and such will always bring these things up to signal level. This sounds like the problem.

If you think about it, the guitar's signal should not be going through the actual circuit except to drive the driver so that this should not be getting to the amplifier. Because the signal is split/shared between the sustainer circuit and the guitar amp, without the preamp in the circuit you could get loading which would reduce the guitar's power and tone significantly. This is because of "impedance mismatching", if we only had the LM386 part of the circuit it would want a 10k input while a pickup might put out 10,000k or something! The preamp part of the circuit allows this sharing of the signal without such problems.

So...it is likely humming is coming from shielding. If you disconnect the battery do you still get hum? This would indicate a wiring shielding problem, not noise added by the sustainer or the circuit.

You may have created a ground loop or lifted some grounding in the guitar somehow. It is a little hard to tell really. This is where you need a lot of perseverance and personal problem solving and why I often say that I find the installation to be a difficult part of the project. Generally you can get a sustainer working and such, but getting it into a guitar and working without noise and EMI can be tricky. As every guitar is different, this really needs to be solved by the person each time.

Keep at it and try all kinds of variations to find the problem. This is why I strongly suggest people always test it as you are doing outside the guitar rather than assuming everything is going to work out just right...it never does! If everything is within the guitar, it makes it difficult to troubleshoot, completely remove the thing to see if the guitar returns to normal without it and such. The problem with it is that with long leads, unshielded leads and things you can get noise. For instance, the driver leads if they get close to the pickups may create noise or possibly what sounds like hum...they need to be kept well away as they are effectively an extension of the coil itself.

Anyway...I hope that helps and it is good that you are getting sustain at least, you should also be able to get the harmonic effect by reversing the driver leads! Good work so far...

pete

Link to comment
Share on other sites

Hello again, I'm about to experiment with this concept a bit, and I'm afraid I'm a bit curious about the preamp and LM386 amp deal.

This should be a quote. I found it in the thread as a quote itself, however, I couldn't find the original post and I have no idea about the context.

the link should be http://www.national.com/ds/LM/LM386.pdf

For instance, the LM386 Data Sheet LINK, page 5 top right x200 circuit, suggests a 10uF cap between pins 1 and 8 (you can leave the trim pot in by connecting the cap to the trim and the trim to the other pin for adjustable gain) which helps with oscillation, the "zobel network" is the small cap and resistor from pin 5 (your C1 connection) to ground. This is also there to help with stability and in this high gain application, the circuit needs all the help it can get. As for the "Fetzer" J201 part of the circuit, this is not something I am familiar with myself. You may wish to substitute the output cap (your C1) for something smaller, I use a 100uF to get a kind of mixed mode and enhanced harmonics.

The circuit that is referenced there, including the recommended modifications, does that included just one part of the preamp and LM386 package, or will that work to drive a unit? I must apologize for my lack of understanding of this part of the system.

Link to comment
Share on other sites

Welcome LarsXI

Hello again, I'm about to experiment with this concept a bit, and I'm afraid I'm a bit curious about the preamp and LM386 amp deal.

This should be a quote. I found it in the thread as a quote itself, however, I couldn't find the original post and I have no idea about the context.

the link should be http://www.national.com/ds/LM/LM386.pdf

For instance, the LM386 Data Sheet LINK, page 5 top right x200 circuit, suggests a 10uF cap between pins 1 and 8 (you can leave the trim pot in by connecting the cap to the trim and the trim to the other pin for adjustable gain) which helps with oscillation, the "zobel network" is the small cap and resistor from pin 5 (your C1 connection) to ground. This is also there to help with stability and in this high gain application, the circuit needs all the help it can get. As for the "Fetzer" J201 part of the circuit, this is not something I am familiar with myself. You may wish to substitute the output cap (your C1) for something smaller, I use a 100uF to get a kind of mixed mode and enhanced harmonics.

The circuit that is referenced there, including the recommended modifications, does that included just one part of the preamp and LM386 package, or will that work to drive a unit? I must apologize for my lack of understanding of this part of the system.

Ok...so it would appear that Risingforce in his most recent post has a layout of the fetzer Ruby that includes these suggested modifications. A trim could be added instead of the jumper between pins one and eight and I am not sure if this layout is clear about the orientation of the caps...make sure you watch the modifications. As I explained, all the connections to the driver and amp are wrong in this illustration but once this was corrected, it appeared to work. I am not sure that this is the best layout, I would use stripboard myself and do it a little different but then I have never built it. From what I can gather this circuit is working now...

No...as I explained back where this quote comes from...

BTW (copy and paste segments to quote, highlight in your post and press the quote button, or press the reply button next to quote option as I have done above and the entire post will be copies into the reply (and can be edited) and has the advantage that a small pink arrow will hyperlink back to the original. Both will copy over any hyperlinks and pics. Do edit these quotes down as you have done to highlight the question being asked...thanks)

The LM386 is a small poweramp. It is designed to accept line inputs such as an MP3 player. Such devices are already preamped and so conditioned to be of an apropriate input resistance to work as per the data sheet.

The preamp part in the F/R case consisting of a single transistor, is designed to condition the very high input of a typical guitar pickup. Without it it would be like putting a big resistor on the input resulting in olss of volume and tone as if perhaps you turned the guitar's volume down to 1~! This is called loading. To prevent loading, you need to raise the input resistance so that the pickup signal can be shared between the input of the LM386 stage and the guitar amplifier without these loading effects. Risingforce misunderstood that and in his drawings the input is on the output...so watch that.

Where your quote from me is from asks why were precautions designed to stabilize the lm386 circuit removed for the "ruby" design when they are clearly indicated and explained in the specifications for the chip? The least we should do is include these few "extra" components to assist the circuit as much as possible for this application.

I have not used the fetzer preamp design, and I am not sure that this is the best. It was proposed many years ago and offers over the original "ruby" design a slight boost to the signal instead of the more basic unity gain buffer of the ruby. It has been widely adopted since, but it was not my personal proposal so it is difficult for me to speak to it or troubleshoot the layouts offered. In earlier designs I used quite a lot of gain in the preamp stage. In more recent designs, I have used a different approach again. If I were clever and motivated enough to do my own design to replace it I would provide for a variable preamp, possibly with some filtering to provide more versatility to different pickups.

For now the F/R is adequate if these components are included for stability against oscillation effects.

Be aware that while a working amplifier wired to avoid as much excess noise (via shielding) in a reasonably quiet guitar is necessary, the amp has no hidden "mojo" and the heart of this project is in the quality of the driver construction. Generally on this thread driver designs are presented that will run from very simple amplifier circuits without the complexity associated with the commercial units. As you cannot "hear" the driver, testing with a small speaker is worthwhile to ensure your circuit is working. Once you are sustaining, the driver is the next thing to look at. Often the quality of the first attempt at a driver may result in sustain but performance and appearance can be improved with a second attempt. Winding a coil is easy, but it is not something that one does everyday...therefore, no one has much practice and the results can vary widely. Be prepared to do this or make a scratch coil before committing to a permanent modification to a pickup for instance.

Also, as a disclaimer, I have got many to work and lots of others have successfully completed this project...but there have been many failures and people who give up. That is the nature of the thing and DIY in general. By building the bits and testing before modifying the guitar or getting carried way and over confident at the outset, this approach should always be taken. For one thing it is very difficult to troubleshoot once installed, so you are best to know that what you are installing does in fact work before you attempt it. Second, there is the statistically likelihood that at this time you may not be up to completing it successfully. There have been people who start this but not complete it, sometimes coming back to it after a while to succeed later...at least this way the guitar is ok...

I of course fail this continually. It gets worse the more experience you get. I recently modified a guitar to take a commercial active electronics with very bad results. Now I am trying to work out how to replace it with something useful! Even here I should have been more wary and tested the thing before I committed to the modification...hopefully we live and learn.

The more advanced things get though, the more this principle can be undermined too. My latest drivers are of an Ultra-thin design (only 1mm thick!). Technically to make them I need to invest a lot in epoxies and a machine to create them, jigs and about 50 attempts. I had to do all of this to create the driver coil before I could test the concept to see if it would even work at all!

However, while I am occasionally working on guitars and obviously helping you guys, at the moment I am leaving the sustainer project to one side. I have been doing this for some years now and it is time I get on with some other stuff, take a break and return to my latest concepts with some new ideas and solutions. However, I am happy to see people still trying this and to help out as much as I can.

I do ask, as many have done over the years, that people who are successful in this project or have helped with the thread, chip in with solutions where they can to ease the burden on me, if for no other reason. Mainly it has been the opinion that the more people who try this, the more innovative solutions will be found which helps everybody and the project more than any one person could provide. This is the power of evolution, but it does require participation...so take pics and notes and help where you can. I hope that with these recent posts for instance that an improved F/R like circuit will be freely available once tested and built by you guys so I won't have to keep posting and suggesting these mods to someone else's design...this has been happening now for years!

keep it up and good luck, welcome aboard!...pete

Link to comment
Share on other sites

For the sake of developing an alternative to the F/R, I've searched around for info on op amp preamps and I believe I have the beginning of a workable circuit.

opamppreamp.jpg

I drew this up looking at a combination of somewhat vague diagrams, so I'm not sure if this is workable? Unfortunately, I managed this from looking at a couple of vague, non-guitar related projects, so I'm unsure about what op amp to use, or even what values the resistors and caps should be at. Apparently R2/R1 will determine gain, which I believe we want relatively high?

The part I'm having trouble with is powering the thing. R3 and R4 are intended to be equal and allow for the use of a single power source. However, this aspect is absent from the schematics of various amps and preamp amp combinations I've seen so far. Is this normally done with an ensemble like this http://i278.photobucket.com/albums/kk83/La...powersupply.jpg ? How would that then be used on this preamp and/or amps like this one?

386amp.jpg

I redrew the schematic for an amp referred to as the "champ" earlier in this thread. It appears similiar to the little gem and seems to have some of the modifications that were mentioned.

R1 1k

R2 10ohms

not completely sure of those

C1 10

C2 100

C3 10

C4 0.1

C5 200

These look like they're all in uF

The pot at the beginning may or may not be necessary.

C5 could perhaps be replaced with a 100 uF

Unfortunately, I've found little info on op amp preamps specifically for guitar. Thus, I'm unable to develop it any further than this until I have an idea about which components and such I should shoot for.

Hopefully I'll be able to refine this to the point where we have a circuit to compete with the F/R. It seems there's a need for a new universal setup.

Link to comment
Share on other sites

Thanks Lars

I have looked and there has been some discussion of various designs, to me opamps make sense, but then others prefer the more compact transistor designs.

Like anything with this project, they need to be tested by a few people as a complete and verified circuit. The only one really approaching that at a basic standpoint is the fetzer/ruby. It may be best to build this design along the lines of risingforce that included my mods that have shown to be effective, then build an alternative circuit to swap out at a latter stage so there can be a direct comparison with a working sustainer...

Of course, the driver is the real "secret" if there is one, so don't get tied up in circuit mojo, the main purpose of the preamp is to prevent loading, secondly to boost lower powered pickups...too much boost and you will get distortion, not more power. The power comes from the LM386 and is limited by the battery anyway. There could be some benefit in filtering out high frequencies (above the guitar's range) as this would help with noise and EMI I suspect, otherwise, aim as clean as possible, economical with power, no exotic components, compact and logical layout (stripboard is probably best) and don't be fooled by more power=better!

A more advanced design would include limiting. Col posted such a design some time ago, but again, I would advise starting out basic and moving up from there. While I haven't done the F/R I have made quite a few different functioning designs. My later ones have my own circuit which is very compact and has limiting to some degree...more on this at another time...

pete

Link to comment
Share on other sites

Hi there,

I'm glad to join, many years after, this sustainer topic, and - first of all - i would thank every contributor for all the usefull informations we can find in this thread.

I'm, at this point, building my own (already build my first driver prototype) made from some material i've canibalized from an old transformer (0.2mm wire), an old planer blade (core driver) some epoxy PCB and a ceramic magnet found on the back of an old pickup.

I'm planing to build the F/R amp these days, but I did some tests with an external amplifier wich allowed me to have some sustain (fondamental and harmonical) on some open chords : Great start...

I think I have to reduce the core height (mine is 5mm) to the ideal size defined by the psw's tests, and fine tune the position of the driver for the moment, there is a little thing I can't understand (even if I've searched for it in the entire thread ...) :

How are connected the pickup wires which are supposed to be connected to the onboard guitar circuit AND to the F/R amp input ?

I've picked the wires directly from the pots connections, but the signal (ie the final sound) of the humbucker i used, seems to be altered when sustainer is on. I have a totaly different attack, and weird sound.

Thanks a lot for your help and cheers from Corsica :D

strib

Link to comment
Share on other sites

Welcome Strib and ianlange11

Strib...well done, a fantastic start...and all on your own too!

How are connected the pickup wires which are supposed to be connected to the onboard guitar circuit AND to the F/R amp input ?

I've picked the wires directly from the pots connections, but the signal (ie the final sound) of the humbucker i used, seems to be altered when sustainer is on. I have a totaly different attack, and weird sound.

Ok...with the F/R...have a look a page back or so about my mods and risingforce's attempt to do a layout of them for the F/R...perhaps it needs another name!

The signal goes from the bridge pickup to the input of the circuit and then onto the switching and controls. Not through the circuit, but both attached to the input of the circuit, only the driver goes to the output. There are variations to get the same effective wiring and it would appear that you have got that bit right!

Another thing, is this the bridge pickup the only pickup? If not, you may be getting EMI through the neck pickup, even if not selected this can occur through the ground.

Most likely however, you haven't said what kind of circuit you are using and the kind of thing you are describing sounds like "loading effects". If the circuit you are using expects a line signal, and you send a guitar into it, the "impedance" will be all wrong. An MP3 player might work, or computer, because these have preamps in them to boost the signal to the correct impedance, a normal guitar does not. Worse, if you try and share the signal between the circuit and another amp like a guitar amp...the tone and everything suffers greatly and the performance of the sustainer effected too. It might work a bit, but not as well as you might hope. In the F/R, the fetzer transistor stage allows for a huge range of signals preventing the signal from getting "loaded down" and optimising the signal for the "poweramp LM386" stage (which does most of the work).

So, if it is working 'kind of', this may be so, but it will work even better without the loss of tone with a proper circuit. So, extremely well done and it sounds as if you have taken all my recent advice and taken it in stages and prepared to redo the driver if necessary...congratulations.

Corsica...I don't think I have had anyone from there, but this thread has reached out to people literally in every continent and so many places it is just amazing.

ianlange11 :D

Boy, it looks good in that pic...where do I get one!

Honestly...I am suffering some ill health still and a degree of tragedy and dissolution. I have been giving the project a bit of a rest but I would still like something to come of it.

I had the idea of a universal kit version of this project taking it to the next step. As I got more carried away in development it became a little less DIY and so the expectations get higher. I am still wondering what I should do about it and perhaps this will become clear in coming months. As you may see, every guitar and persons application is a bit different. I could sell a built circuit of improved design and a pre-made coil like this that would fit most strat pickups and perhaps p-90's. Switching the thing with multiple pickups is a bit of a worry and now I am thinking that it probably needs a bit more of a preamp boost (perhaps another stage in the circuit) adjustable for different pickups.

So...do I sell informally the concept as it is with a big disclaimer that you are on your own as far as getting it to work in your own guitar. Or, do I try and develop it as an entire system. Hmmm.

So for these reasons it is on hold till I am inspired or I happen across someone to enthuse me more and help me iron out the last of the problems.

Initially, my idea was to solve a lot of the problems everyone has and put us all on a fairly even playing field. That is a tested built circuit purpose designed by me for this project that I myself have successfully implemented and a coil that is likely to surpass anything that could be home built, potted in epoxy and suitable to mount on a pickup as in the picture or een as a stand alone device.

To that extent I was successful, but would it work for everyone? People are frustrated with the F/R and my circuit includes some basic limiting to give the thing control and is more compact. Many are frustrated with the availability of wire and parts, I can't get a J201 and the 0.2mm wire seems to have disappeared from shelves (I have an industrial roll now). So, I figured I would design and build these things myself...but then, if this is a "commercial" proposition do I really want to publish the circuit design. Very frustrating! I never used the F/R design myself using all kinds of circuits with success, but it is not ideal in my opinion. As you can imagine, I think this thread has been going for 5 years now plus enormous amount of work "offline" in developing and thinking about this. Should I put myself in a position of having to hand build circuits and coils, how could I make this profitable? You can see how much 'boutique' stop boxes cost, many are not even the makers design...could I charge like that...probably not! Of course, one of the benefits of the concept above is that there is no box, magnets or anything else, but at least sith a stomp, you can expect to plug it in and the thing is guaranteed to "work". This thing demands a total guitar rewire and a lot of troubleshooting which I can not be responsible for.

So...some heavy duty conundrums and so I guess I have taken the easy way out for now and just put the whole thing on hold. If anyone has any suggestions though, feel free to comment here or to email me if you like.

Obviously the thing is close to my heart and I spend a lot of time (nearly everyday) lending assistance where I can to the DIY'ers out there. This thread is kind of unique in that it was never a "look what I made" vanity thing. In fact most of the development has come from encouragement, direct input from people trying it themselves and at time some healthy competition. So, I feel a little obligated since I started the thing and would miss it if it weren't around. I am still waiting for some of our intrepid tinkerers to make the breakthrough that has eluded me and I must say there have been no end of trying to great effect.

However, there may come a time where I should leave it to others and get on with other things...or fully develop this project and try and sell it to you guys!!! I keep saying this of course, but then something happens...sometimes life just gets in the way. The next few months look to be stressful, but perhaps by October or the end of the year I will have cleared away a few of these things and get a bit more perspective.

So, thanks for asking and good luck to all those trying this project...it does take some courage, but it can be done with perseverance (something I am lacking just now)...so keep at it and stick around and help others when you crack it...

pete

Link to comment
Share on other sites

Ok...with the F/R...have a look a page back or so about my mods and risingforce's attempt to do a layout of them for the F/R...perhaps it needs another name!

The signal goes from the bridge pickup to the input of the circuit and then onto the switching and controls. Not through the circuit, but both attached to the input of the circuit, only the driver goes to the output. There are variations to get the same effective wiring and it would appear that you have got that bit right!

Ok pete, but what is disturbing me is that the original bridge signal is splitted in 2 parts and go to the F/R input AND the guitar controls (I consider this wiring in "paralel").

Have a look at my scheme (Based on a typical wiring diagram from SD) :

image1.gif

In this case : is the signal of the bridge pickup divided ?

Most likely however, you haven't said what kind of circuit you are using and the kind of thing you are describing sounds like "loading effects". If the circuit you are using expects a line signal, and you send a guitar into it, the "impedance" will be all wrong. An MP3 player might work, or computer, because these have preamps in them to boost the signal to the correct impedance, a normal guitar does not. Worse, if you try and share the signal between the circuit and another amp like a guitar amp...the tone and everything suffers greatly and the performance of the sustainer effected too. It might work a bit, but not as well as you might hope. In the F/R, the fetzer transistor stage allows for a huge range of signals preventing the signal from getting "loaded down" and optimising the signal for the "poweramp LM386" stage (which does most of the work).

So, if it is working 'kind of', this may be so, but it will work even better without the loss of tone with a proper circuit. So, extremely well done and it sounds as if you have taken all my recent advice and taken it in stages and prepared to redo the driver if necessary...congratulations.

You pointed it ! :D

I used a little guitar amp to do the job, but i know that I have to make the F/R soon (I'm waiting for some components right now) for improving my tests;

When I told you that I have larsen and EMI, I had only the bridge pickup and the center single coil on the guitar. Neck pickup has been replaced by the driver.

BTW, I plan to wind a special pickup like yours, which will have a typical 0.063mm (AWG42) wiring for the passive pickup stage, and a special stage above with 0.2mm wire for the driver, but it'll be another story ! :D

Best regards

Strib

Edited by Strib
Link to comment
Share on other sites

BTW, I plan to wind a special pickup like yours, which will have a typical 0.063mm (AWG42) wiring for the passive pickup stage, and a special stage above with 0.2mm wire for the driver, but it'll be after I will have all my tests successful !

Excellent, and I hope all readers will follow your example and success. No harm can be done by such experiments. You have shown for instance that your first driver worked even with a scratch circuit, so you can now feel a little confident of your circuit and then your installation will be another problem.

Even with a middle pickup and expecially the neck pickup, you are going to have to get pretty clever with the guitar's wiring. I would suggest for now, completely disconnecting the middle pickup (both hot and ground) though you can leave it in, as it is still possible that EMI is getting in there. Some of your problems may indeed be from this middle pickup. It is one of the difficulties in troubleshooting from the other side of the world!

Otherwise, the diagram is excellent is showing me exactly what is going on. Wired this way, the pot is cutting signal from the pickup (working as a volume control) and it may work a little better if the pickup when direct to the circuit and then the control as I tried to describe in the last post.

It would seem that Risingforce's layout used in your pic worked and includes my suggested modifications. We could call it a sustainerized circuit or something...an improved F/R!

For me the most difficult bit is the installation, but then perhaps I am more practiced at the coil winding and circuit stuff now. You will be looking at a 4pdt switch to turn the thing on and off, unless you can think of a better way that will bypass the extra pickups. You could also play with the pickup and driver coils in parallel...I got some interesting results both way, sometimes this option will create more switching options...but you will still need a pretty powerful switch and even then you may get a little switching noise.

Winding a custom pickup is a bit of an adventure. You may wish to consider modifying a pre-wound cheap pickup. This tends to be cheaper and easier than making your own...unless you are pretty experienced in doing this already. Making pickups is a whole other project in itself.

Don't be too concerned about the blade thing. My blade design worked well, but I have got pretty good results with modified pole style pickups. There is a slight loss of sustain if strings are bent between the poles, but not disastrous. BTW the plane blade was a pretty cool idea in sourcing material.

If this all works for you and you get the bug, you may find yourself experimenting with other circuit ideas or driver designs. That's when referring back through the thread can give you a huge range of ideas. Unfortunately, many a good idea failed to work, others were ideas never built and some were a little too adventurous. The very basic "thin coil" single coil design still has a lot of merits and if it does the job, that is probably a good design to perfect. That is where the "ultra thin coil" in the top picture came from. Alternatively, dual coil designs have very low EMI potentials, but at least twice as hard to build. They also have a range of different design parameters and to some extent the specifications (optimum wire size, etc) goes out the window. Alternatively, the sustainiac like dual coil bi-lateral design is interesting but very difficult to combine as a pickup. One of the holy grails has been the idea of a mid-driver, but I have tried many times with only limited and no practical success.

Anyway...one thing at a time and you seem to be progressing well.

pete

Link to comment
Share on other sites

Winding a custom pickup is a bit of an adventure. You may wish to consider modifying a pre-wound cheap pickup. This tends to be cheaper and easier than making your own...unless you are pretty experienced in doing this already. Making pickups is a whole other project in itself.

Hello pete, thanks a lot for your quick response. I know that i'm on the right start, I'll be back with more experiment.

I use tu wind my own pickups as I make my own guitars (you can have a look here : www.strib.fr )

Thanks again and, see you as soon as possible :D

Strib

Link to comment
Share on other sites

Hi everybody. I am from inner Rio de Janeiro, Brazil, and I have been following this thread for a while. I have built my own version of the amp, a modified F/R, with a BC550 instead of an FET, configured as a unity gain emitter follower to reduce load as a pre-amplifier/buffer. I have successfully tested it both as an acoustic device using a small telephone loudspeaker stuck to the headstock (which generates a lot of unwanted microphonic feedback) and with a disassembled modem mini loudspeaker, using its coil next to the strings. I don't know if anyone has already tried it, but I'm thinking about wiring the 8-ohm driver coil around the mid pickup, just like a normal ac transformer, instead of stacked coils. This arrangement should save space and lots of hassle. The idea is to turn off the mid pickup whenever I turn on the sustainer system. I plan to build a basic system without altering the front looks of my guitar, just adding push-pull pots and the works. I also want to congratulate Pete on his patience, dedication, ingenuity and generosity. Best wishes.

Link to comment
Share on other sites

Thank you Adiel and welcome...for some reason I always wanted to go to Rio...

I don't know if anyone has already tried it, but I'm thinking about wiring the 8-ohm driver coil around the mid pickup, just like a normal ac transformer, instead of stacked coils.

Him, I am not sure if I a following this right...the driver coil is going around the outside of the pickup coil? No, this will not work as there will be too much space between the coil and the magnetic core. Also, don't underestimate my "thin coil" design. A deep coil (which is what such a coil would have to be) has different characteristics. Even the gauge of the wire in this design is important. Far be it from me to stop experimentation, but there are limits. I have tried a few of these kinds of ideas. Anouther would be to put the coil below a pickup, but again this does not work.

As for having the driver in the middle pickup...from the post above...

One of the holy grails has been the idea of a mid-driver, but I have tried many times with only limited and no practical success.

driverinstalled2.jpg

Above is one of my more notorious and elaborate mid coil driver experiments. This has 4 cores (two outer shields), and two coils, solid potting and "high tech" looking aluminium construction...ever some LED's ! But alas, no dice. I made some bilateral versions recently too and again not good enough. Note, neither of these also work as a pickup.

The reality is that the mid-driver is very elusive. One of the better more promising ones was something CurtisA was making, a neat bi-lateral design with some novel circuitry...unfortunately, it seems to have been put aside (are you still working on this Curtis?). So you see, it is not likely to be successful, and your proposal is not likely to work at all, if it is as I described (although I could be completely wrong in my understanding).

A guitar can be made to look "stock" with a pickup/driver in the neck pickup...but there again, push pull dpdt pots are not likely to be enough to switch the thing on and off.

Again, be forewarned and take a leaf from Strib and my advice to do as you have been doing, one step at a time and don't commit to ideas that may not be achievable. Acoustic "sustainers" that vibrate the strings by vibrating the headstock are an interesting thing, and worth experimenting with...make a bit of a racket though. Generally you need a lot more power to shake the whole guitar than these little amps, but the principle is similar. One technique is to cut the cone out of the speaker and add a small coin or washer to the centre of the speaker to give the vibrations some momentum, avoid burning out the coil and increasing vibration potential. It is also a bit quieter (still makes a fair buzzing though). My experiments with this also tried to 'shake' the tremolo bridge in a strat to produce a sustain effect, unfortunately, the EMI issues still applied, but I do like this idea. Piezos are cool, and are non-magnetic but have not enough throw to shake the strings....grrrr! Memories!

Sometimes however, people are a little put off by the idea of getting the right wire and physically winding the coil...maybe a few times even. But really, 10 minutes is all it takes, most of the work is in getting something rigged up to wind it to. The below linked pictorial of the winding of my pickup/driver is a good instruction. I took these pics in an unusual fit of organization and it not only records the making of if, but it was my first wound to a pickup and I didn't even know if it would work. The secret of the success is really care and attention to detail and having everything prepared...then it is seriously only a few minutes work to wind.

That said though, obviously I have tried some wacky things and I don't have all the answers. I promote my "thin coil" design as something that can be made relatively easily and can work. However, someone may come along with an even better idea, something I haven't thought of or something I tried but failed where someone else might succeed. So, far be it for me to stifle anyones ambitions. There are some known limits that need to be addressed though, and for a mid driver this needs to some how not interfere (EMI) with the bridge and neck pickup or get in the way (a major fault of mine above) but still put out enough power to shake the strings...a tall order. I believe it is possible, but you would have to be pretty clever and a crude simple coil will not work (unless you had a way of modifying pickups to protect them, or some fancy circuit with synchronized cancellation signals or something).

One of the great things about this project is that it does make you think, hone problem solving skills and you end up pushing the limits of what is possible in many case. However, at some point one needs to come back to reality. I spent a year with a very novel HEX driver concept...only to turn around and do the pickup/driver to produce the same basic effect. The Hex things were complicated quirky and expensive and not DIY...while the thin coil is cheap and easy and worked! Now, if I could have settled for not trying to be too clever with it, I could have saved myself a year and a lot of work...but there you go, another personality fault!

Ok...welcome and thanks for the compliments, it sounds like you have been having fun with it and if you stick at it and are prepared to make compromises, you are likely to succeed...good luck, pete

Link to comment
Share on other sites

Thanks a lot for your detailed response. Actually, I live an hour and a half from Rio, in the state of Rio de Janeiro (nice city, though a little violent...). If you ever come around, let me know, ok?

About the project, one idea that could work is to use 6 mini modem loudpeakers without their membranes, inside a pickup cover (I have an Ibanez H+S+H guitar, that's why I intend to use the system in the mid pickup position), or assemble a dedicated pickup.

As soon as I have something more tangible, I will post pictures and details.

All the best, and see you soon.

Link to comment
Share on other sites

(nice city, though a little violent...)
Well, being a scardy cat, this is one of the reasons I don't travel more widely. I live in a very multicultural society in Australia, most people seem to have come here (at least round my area) running away from somewhere else (even brazil!) But you know, good people everywhere, so far from me to mention it secondhand, the "lucky country" has significant problems too.

About the project, one idea that could work is to use 6 mini modem loudspeakers without their membranes, inside a pickup cover (I have an Ibanez H+S+H guitar, that's why I intend to use the system in the mid pickup position), or assemble a dedicated pickup.

Well, it's a plan. Very much the HEX idea. But beware, there are a lot of difficulties in this plan. Don't assume it will or you will get it to work in this format. The impedances will be all over the place and this would be a completely different in response (phase is likely to be an issue) to the coils I have shown to work. The "thin coil" idea seems to work by running mainly in the pure resistance area (not a varying impedance with frequency). Also, the wire is such to be able to put out enough magnetic energy to move the strings, not a thin membrane and a little air. The principle is simple but getting the conditions set up so it will actually do what you want it to are a lot more tricky.

So...as always....do not commit experiments into the actual instrument, use it to test all devices by holding the driver above the strings. But be aware, that even then, trying to get the thing to work close to other pickups is going to be a problem. There is a catch22, the driver has to put out EMI, it is what moves the strings...inevitably this will get into any near pickups. Too close and you will get a howl of squealing oscillation feedback. Without any strategy to avoid it (six coils is not enough I suspect) the amplified driver signal will go straight into the pickups and out the amp!

Anyway...it is possible to make an HB version should these experiments prove to fail.

good luck... pete

Link to comment
Share on other sites

It is really very interesting to see how the phase affects the effect (not on purpose...), and my first attempt to build the coil was of no success, but I did not follow the instructions thoroughly, though. I disassembled an old 3W speaker and used its copper wire to wind a coil on a ferrite bar, and put a magnet behind it (lol). As you may have guessed (and must be laughing wildly), all I got was a faint oscilation. The nearest I could get to the real thing was still with the small 'membraneless' mini speaker, which works like a poor man's e-bow. I am going to get an old damaged single coil pickup and start again from scratch.

I really liked the idea of using the TDA7052 as the amp, for it simplifies the circuit a lot. The circuit I have built is also working perfectly, my problem now is going to be the driver. Maybe I will try to push the magnets a little upward and wind the driver on the top of the mid pickup, like your idea of a thin driver.

I will keep you posted.

Link to comment
Share on other sites

I really liked the idea of using the TDA7052 as the amp, for it simplifies the circuit a lot. The circuit I have built is also working perfectly, my problem now is going to be the driver. Maybe I will try to push the magnets a little upward and wind the driver on the top of the mid pickup, like your idea of a thin driver.

Ok...but be aware that I have tried everything I can think of and the basic "thin driver" concept is not able to work that close or between two HB's unless someone can overcome the catch22 aspects above. What is possible is to make a driver HB sized or replace the neck pickup with say a compact HB and a driver next to it, or perhaps a pair of thing coil's on top of an HB somehow and use it only with the bridge pickup in sustainer mode...just as the sustainiac and fernandes are restricted too. I have designs for an HB version of the illustrated Ultra-thin version that could be built into a cover for a neck pickup for instance and from the work shown here by other's, there is no reason that this wouldn't work or better than the single coil version. However, it still would not be good enough as an "elusive" mid-driver device.

You did hint at some of the advantages of the m id-driver concept. I experimented with the idea because if possible, it would greatly simplify installation so that push-pull pots or even a pickup selector could operate it. However, most people assume that there would be enormous benefits to being able to use the thing with either bridge neck or both pickups...this is probably and in my experience a lot less of an advantage as you might assume. With a dedicated mid-driver like the one illustrated above and others, well, you loose the mid pickup completely which is far more of a "loss" to the tonal range of a three pickup guitar.

Part of the catch22 is that, the more power you push into the driver, the more EMI you produce and so oscillation feedback. Most strategies to control the EMI seem to reduce efficiency, so you need more power and you end up where you started. Other ways, as in the above mid-driver used both dual coil EMI cancelling and ferromagnetic shielding. It did work to an extent, but to do so it had to be virtually touching the strings and seriously got in the way IMHO...plus you loose all the mid-pickup quacky combinations.

The driver is not hard to build, so don't be put off on that account. Overcoming the mid-driver problems was beyond me and a lot of other even more clever people here. There is only one example that I can point to, the Dizzyone strat that this seemed to work, but that was not from this thread. What I heard and have posted is very impressive and though I did see a pic, it has long since disappeared. The details were secret and not shared, but I got enough to know that it largely replicated sustainiac's patent with a complex phase correcting circuitry and a bi-lateral two coil driver. While there is a patent held, there is no evidence that it was ever built and was never offered commercially, possibly because the conventional way was better.

If people would like to think "outside the box", after recalling the ideas I tried many years ago to "shake the tremolo" acoustically, this would be extremely cool! Not only no pickup modification, but it may well fit neatly into the trem cavity. The big problem is being mechanical, there are losses to overcome and if "moved" magnetically...all the EMI problems may exist in that the device would be situated right under the sensitive magnetic pickups...

Ahhh...as they say, "if wishes were horses, then we could all have something to ride"...or something like that!

Keep it up...

pete

Link to comment
Share on other sites

Hi all. I read the WHOLE thread! You're right PSW... it should be read backward.

Well. I'm feeding-back like a a madman on my guitar right now. It seems kind of fitting on the fourth of July.

I feel like Jimi Hendrix playing the Star Spangled Banner.

Anyway, here's what I did. I don't claim it is DIY...more like lateral thinking.

I went in the direction of the Sustainiac Model C. I bought this "GHOST TRANSDUCER

from "Vidsonix" http://www.vidsonix.com/vidsonixnew/info_vxgh72.htm

You can read all the specs at the website.. I made the hook-up like this:

I clipped the wire from the bridge pickup and attached a guitar cable directly to it.

Then plugged that into the input of a little practice amp (25W yamaha)

Then disconnected the speaker in the amp and attached the leads from the "Ghost Transducer"

Now, playing the guitar, the neck pick up acts normally and goes to my little Vox DA5 5watt amp.

The bridge pick up is now amplifying the Ghost Transducer.... It actually works like they say it does

because when I hold it against the wall, or the wood floor it acts like a speaker.

Well. you can see where I'm headed.. right? Holding the Ghost transducer against the guitar body

makes it feedback like crazy. Not electomagnetically, I can get that if i hold it to close to the

neck pickup. This is vibrational. Right now I have it clamped to the head of my SG with

clothes pins. It acts just like the Sustainiac website says about their Model C ....As if

l the guitar is alive in your hands. Here's some specifics, with the transducer on the head:

The yamaha amp is run at about 1/2 volume, and 1/4 distortion. Base and treble at middle

Changing the settings of volume an distortion produce diffefrent feed back characteristics.

Also, strangely , by changing the settings on my Vox amp (it has "style" and "effects"

settings) the feedback characteristics change.

Also the feed back is consistant.. that is, at given settings. certain strings, and certain notes

seem to dominate. String muting is required because sometimes a given string or two just starts to vibrate at some harmonic. Not only the string your are playing. Chords are fun. One or two stings take over and just go to their own

place in about 3 seconds. It all seems to me pretty much as described on he Sustainiac website about their Model C.

I did try switching leads to see if one phase acted different than the other. But they both seemed similar to me. As far as sustain... depending on the settings... some notes will sustain forever... some act normally, and some start feeding back. All strings will feed back, but hi e has to be coaxed into it by bending or vibrato.

It is very fun. learning to control the feedback. There are obviously infinite possibilities.

The vibrations causing he feedback could be manipulated with pedals, or amp effects. After only a day

of playing around, I can see a whammy bar would be useful, and also a volume pedal.

Turning up either the volume, or the distortion is what brings on the feedback.

Like I said,,above 1/2 and the guitar is uncontrollable. So maybe the 25 watt practice amp is a good fit.

Anyway... this this does work!!

Is it any cheaper that the sustainiac? Maybe not .. Transducer $25. Practice Amp ?$100.

pickup signal spliter... ?$$$ and electronics..??$$$. but it is a definite option for a DIY project.

I'm glad that I could finally add something to this thread. I've been enjoying it for a long time.

I must say PSW. You are the most generous person wiith your time and knowledge that I have yet seen on the internet. Thank you

Link to comment
Share on other sites

Hi Al s. It is very interesting to see and be able to take part in such a fruitful, fun and successful thread.

Your idea is very nice, I got almost the same results as you did with the fz amp and an old telephone transducer stuck to the headstock, but the acoustic type of 'sustainer' I built had too much feedback of the unwanted kind.

Maybe I did something wrong, but I think I will stick to the magnetic type anyway, following Pete's advice and wiring it on the top of the pickup...

By the way, Pete, do I have to wind about 112 turns to have a thin 8 ohm coil using 0.2 (awg32) copper wire?

Link to comment
Share on other sites

I must say PSW. You are the most generous person wiith your time and knowledge that I have yet seen on the internet. Thank you

Wow...perhaps I should just stop feeling so sorry for myself :D . Actually all credit goes to all the people who have contributed and still keep the thread interesting and alive! It is quite an amazing thing really and completely unplanned.

Hi all. I read the WHOLE thread! You're right PSW... it should be read backward.

Ahh...yes, that is a very bad idea! If I had known what it would become, it could have been a forum in itself with different sections of interest that could more easily be found. Still, it is what it is!

ghostlftsm.gif

Hmmm...yes an interesting thing. Basically it is a speaker of course and being electro-mechanical it is electromagnetic, basically the idea of the model C.

Your experiments have illustrated some of the advantages and limitations of the "acoustic sustainer" principles. Obviously you need a lot of power to effectively shake the whole guitar (15-25watts compared to 1/2W). A cheap way to dabble in the effect is to push the guitars headstock lightly against the speak baffle of a moderately loud amp. This was often used by studio musicians to get feedback on demand for recording.

While with the electromagnetic sustainer we are only trying to activate the strings which are tuned to the frequency that we are sending to them. in trying to vibrate the whole guitar you are coming across a lot of additional resonate frequencies that create both hot and dead spots...hence the uneven response. Also, you must have a few leads trailing around the instrument to achieve the effect!!! An, I gather the thing is'nt quiet...the transducer must itself be making some noise.

It is very fun. learning to control the feedback. There are obviously infinite possibilities.

The vibrations causing he feedback could be manipulated with pedals, or amp effects. After only a day

of playing around, I can see a whammy bar would be useful, and also a volume pedal.

This is true, once you have the capacity to do this, you need to learn different techniques, especially damping and you can see the advantages of a tremolo to add more expression to long notes and a volume pedal to control the dynamic contour.

Since you have read the whole thing, you may have come across the posts by spazzyone/shawn that took this idea and basic set up and ran the whole thing through an unmodified rail pickup with a PA amplifying it. Enormous impedance mismatches but he swears that he was able to get it to work with sufficient power. Although others did not follow him in this, it is interesting none the less and started a lot of work in dual coil drivers as a result. He even kindly donated to me a rail pickup...thanks shawn, generosity not forgotten!

There are dangers to this kind of thing, unlike your experiments. It may be possible to blow an amp with such impedance mismatches or at least burn something out, and the results were not really verified...but he did post a video at one point that suggested that he was onto something!

So...good for you and it is nice to hear from a long time "lurker" which I know there are a few (given the number of daily visits) that encourages me to continue to contribute too. Anyone with an interest should feel free to contribute.

Welcome to the sustainer thread and to PG, and good to see people keeping the "tinkering" spirit alive and having a go. I suspect that people like this will play a major role in solving world problems in coming years just as they did at the start of the industrial revolution (ironically in creating a lot of them) instead of the mindless bickering and commentary that is far too persuasive. Perhaps one of the more interesting things about this thread is that it shows how many people are still in touch with this "spirit", enjoy the challenges and the lessons learned and I hope that this will hold in good stead for everyone no matter what they do in other aspects of life. I know that seeing the interest and ingenuity helps me personally...so there is more than a little self-interest of course!

OK...till later... B)

pete :D

Link to comment
Share on other sites

Hi Al s. It is very interesting to see and be able to take part in such a fruitful, fun and successful thread.

Your idea is very nice, I got almost the same results as you did with the fz amp and an old telephone transducer stuck to the headstock, but the acoustic type of 'sustainer' I built had too much feedback of the unwanted kind.

Maybe I did something wrong, but I think I will stick to the magnetic type anyway, following Pete's advice and wiring it on the top of the pickup...

By the way, Pete, do I have to wind about 112 turns to have a thin 8 ohm coil using 0.2 (awg32) copper wire?

I missed this while I was posting!

The number of turns will vary and the online "calculators" are in accurate. Basically you will have to measure it with a multimeter...see the pictorial. The size of the inner core, how tightly it is wound, how thin and overlapping layers, all play a part. Generally, a 3mm deep coil will be about 150 turns perhaps. At first, the resistance rises slowly, but then as the coil gets bigger it will rise rapidly...so after a hundred turns...start to measure by lightly scraping the wire and measuring from the start to that point, and keep winding to about 8 ohms. A little less seems to work fine but no lower than 7 ohms! Don't forget the PVA potting...this is important as the coil will try and vibrate itself, you need to avoid this as it creates it's own EMI signals and dramatically cuts efficiency. PVA is waterbased and safe, other things are to be avoided. While more recent coils are epoxy potted (in fact there is no bobbin, just wire and epoxy) it took a lot to find anything that works and I needed to build a machine to wind them...plus they are dangerous and messy. For coils like the DIY design with this kind of wire and PVA or wood glue, I still wind by hand. A few hundred turns really does not take long at all, and is kind of relaxing in it's own way. It has long seemed that the coil winding puts people off the most, but that is because they have not tried it. The harder part is working out a bobbin or something to wind it to! With PVA, it is possible to start again and at least it is safe and cheap.

I have tried a few small weighted speakers and such for my experiments in the past with these tiny amps. I had one working ok with a small speaker taped cone down around the jack socket on the face of a strat for instance. As I mentioned before, I did try a few different things to try and shake the tremolo in a strat guitar...I figured it ought to be easier than trying to shake the whole guitar! Also...there are limits, at least for me, but it would be cool!

If you look at it objectively though, I guess a silent and simple electromagnetic coil working directly on the strings is the most efficient and practical approach.

Anyway...enough from me...

pete

Link to comment
Share on other sites

Hi Adiel and Pete. Thanks for the welcome.

I'm still having "fun with feedback"!

Pete, It seems that you have a good handle on my experiment.

You are right on about the advantages and limitations of "acoustic feedback"

There are definite "hot spots" and "dead zones" For example my g-string

is an amazing live wire its whole length. I can bend nearly any note into a

mutation of sound. The low E string also feeds back when open at the drop of a hat.

Other strings and notes are much less prone to feedback. By increasing volume on

the transducer amp, though, I can get any note to sustain and then feed back.

This is where I am thinking a volume pedal would work well. This requires damping of the

other strings, though. because the "dead notes", when given enough volume/vibration to

feedback when excited by striking, is already enough volume to cause the 'live' strings to

be excited on their own at this volume/ vibration level.

I am wondering if this is all a factor of the acoustics of my particular guitar,

and that each guitar would be different?

You are also correct that the transducer itself makes some noise. It is audible at very high volume

levels, though, higher than I am normally using when playing around. An even then its hard to tell

because it is the same frequencies coming out of the guitar amp. So over all it is not annoying,

it could even be considered an "effect"..... "screaming guitar head" !

Putting the transducer on the body of the guitar was noisier though, it wanted to turn the guitar into a speaker.

You are also absolutely right that this whole setup is not very stealthlike!

Extra wires dangling, Not to mention the hockey puck attached to the head of the guitar. Oh, it is now

clamped on with a capo. How inventive is that?

I think it could all be cleaned up a bit though. Hiding wires, etc. Of course,

this system will never be a elegant as the little driver/mini amp solution.

I guess you could call this "acoustic" version quick and dirty. Still, it is a lot of fun.

By the way you mentioned putting the head of the guitar

against the amp to get feedback. Way back in the thread someone, a bass player,

I think, mentioned this and thats what lead me to try this. Am I correct that this feedback

that I am getting is the sound we are familiar with from records, concerts, etc?

Then the mini amp/driver/fernandes method is a totally unique sound...? I've heard your sound clips.

Very nice!! They do have an "other worldly" feel. Some day I'll get my hands on one of those.

Meanwhile back to my Jimi imitations.........Al

Link to comment
Share on other sites

Lovely post Al

What you are doing is very similar to the way traditional feedback works and not really that different from our sustainer stuff. Even there, depending on the guitar, there can be notes that certainly work better than others, but generally it can be fairly even. In all systems lower notes tend to predominate and you do need to change the way you deal with the guitar...as if it were super loud or alive. Damping is very much the key...check out the way people like EVH, Santana or Jimi who play super loud are able to control this in various ways. It kind of teaches this yourself and even without the sustainer these damping habits become a part of your technique for a cleaner sound and more control.

In the mini little transducers I made by cutting the cones out of computer sized speakers and even the frame and wieghting the voice coil...it was an irritating buzz...so not good!

I guess you could call this "acoustic" version quick and dirty. Still, it is a lot of fun.

And this is really the point of all of this is it not...so well done!

Then the mini amp/driver/fernandes method is a totally unique sound...?

It depends on whose hands it is in. The most famous recording is "I still haven't found what I am looking for" (U2) where it is used predominantly and often assumed to be an ebow or perhaps a synth.

My recordings were fairly basic but it gave people a bit of a taste and for some at least proved that the project could work!

I actually haven't been playing the sustainer thing for a long time, but it is a fun thing to have. It is a great recording tool and certainly gives the impression, sound and feel of a really loud guitar even though all of those clips were made silently into the computer with headphones.

So...keep developing it a bit, try running some effects through the driver signal and see if that has any effect. Very early on (even before this thread) I tried things like a flanger on there. This effect sweeps the phase over time so as it sweeps it would hit of various harmonics as it slowly swept over the resonant frequencies. I got a weird kind of chirping bird like sounds out of it that had a bizarre kind of relationship to the notes, derived as they were from the strings themselves, but otherwise a bit of a gimmick. So, more fun to be had.

pete

Link to comment
Share on other sites

Hi there !

Tests passed successfuly :D

I've built 2 preamp/opamp to do my tests :

- first fetzer ruby, which was not loud enough, because of the lm386 N1 chip (only 0.7w).

lm386.jpg

As I was almost sure about the driver, then, I managed to build another amp, based on a LM741 preamp and a TBA820M opamp.

The difference between the 2 circuits is very important, with only one pot for the gain, here it is :

TBA820M.jpg

This is a prototype, I've now reduced the size of the PCB to 5cmx3cm . That will allow me to install it directly into electronic cavity.

I've built 2 differents drivers, the first one with a piece of planer blade, 2.5mm thick :

010.jpg

The second, made from transformer scratched :

011.jpg

I first ued a ceramic bar from an old single coil, but the sustain was not very accurate, especially on the G/E/B strings (because of the diameter of the chords), then I replaced the bar with small square neodymium magnets (6mmx4mm 2mm thick), and this solved the problem.

My old rusty guitar is now ready to cry :

012.jpg

Here are 2 divs movies during first tests :

fondamental mode

harmonique mode

Sustain forever B):D

Cheers,

Strib

Edited by Strib
Link to comment
Share on other sites

Beautiful work there Strib...congratulations!

Both drivers look fantastic and the circuit very professional...the proof of course is in the sound clips, the harmonic one a particularly like...nice control for just starting out playing with the device, good technique!

This is exactly what the DIY version should do and people should be aiming for!

Now of course people are going to want to know more about these circuits, especially the second one. Are you prepared to share? I am surprised that the F/R wouldn't work but I do think there are limitations to the design, using an op-amp for the preamp allows for a lot more control over the gain and so allows adjustment for the guitar.

Normally I would have suggested that more magnetic and amplifier "power" is perhaps not the best idea...but it seems to have worked for you. In the circuit, are those LED's a clipping circuit or indicator lights...again, clipping has proven not to be such a good idea, but then maybe it provides some compression that is working for you creating a limiter effect. I guess the proof is if you can play the guitar completely clean with the same control.

Anyway...I am so glad it has worked for you and that you have posted such a great pics and clips that will encourage people as much or more than words I could offer...

Many thanks, a most valuable contribution!

Pete

Link to comment
Share on other sites

Guest
This topic is now closed to further replies.
×
×
  • Create New...