Buzz Feiton/earvana And Similar Products

[Truth_David]

Hi all,

I spend most of my time on the electronics forum, so I was not sure where to post this question. I have been in touch with my luthiers regarding this issue, and they state categorically that any benefit derived from the Buzz Feiton and Earvana systems is lost as soon as you play a fretted note.

This was my reply, which they made no attempt to address, but instead directed me to a very interesting website, where the subject of intonation and the problems with the equal-temperament system are discussed at some length, although without going too much into the actual mathematics involved: http://www.acousticfingerstyle.com/gtartuning.htm

Here is what I wrote:

Thank you Simon,

If I read between the lines regarding the BF, Earvana and similar systems, what you are really saying is that they are marketing products based on sales hype, rather than scientific fact, is that correct? But I have to say that I watched a video of the earvana system and its subsequent effect upon tuning, with a side by side comparison of the fretted notes at position 1 - 4 compared with the open string on a 'normal' guitar and those obtained from a guitar fitted with the different intonation of the earvana system. Of course, things can be manipulated so that they can fool one into believing that a certain effect is being produced. Without being able to reproduce the same conditions, using the same equipment, it is difficult to know for sure.

But the methodology does make sense, when compared to the way a piano for example is tuned. And I must say that it is becoming increasingly obvious to me that there is a problem with the concept of having the possibility of pressing a note out of tune accidentally at any fret position of the instrument. The same as having a scalloped fingerboard, but to a lesser degree.

This has been further brought home to me recently by the fact that one of my friends was tuning his instrument to pitch, but whenever he played chords, everything was totally out of tune. Upon examining the guitar, I realized that the setup had been done poorly, and that the nut slots were not filed deeply enough. This, combined with his poor technique, and pressing down too hard on the strings (believing that it was necessary to press the string down to the fretboard in order to produce the correct note) resulted in his chords being completely out of tune.

I then started to pay much closer attention to my own instrument and found that in fact even on the best set up guitar I own and use every day, the same thing was the case - that there is always a certain distance between the fretted note and the fingerboard. When using light strings, as I do, the slightest extra pressure on the string can actually force it too far towards the fingerboard, which will not produce the correct tone, it will be slightly (or very) sharp. On a classical guitar this is even more pronounced.

I am aware that the best musicians unconsciously make minute adjustments in terms of bending or pushing the string so as to produce a correctly pitched note, and am to a certain extent aware of doing so myself.

Now, none of this is so noticeable until you start to play complex chords comprising of a mixture of open and fretted notes, especially with intentional dissonances, such as a m7+5 (take Bm7+5/E - E-B-F#-G-D-E, could be Em9-5 played at the second fret position, with the G and top and bottom E open, or take a derivative of that chord A-F#-G-D-E, a sort of Gmaj13/A or D11/A) and the bad notes become immediately apparent. This should be a beautiful resonant textural chord which can substitute for a Bm or Em, but instead sounds out of tune.

Now, given that as I said previously, I am presently experimenting with adding further notes to these chords with the right hand, whilst simultaneously picking or strumming the open notes with my other two fingers, the dissonances start to become really marked, especially when amplified (and on an electric with a vibrato bridge, the subsequent bridge movement makes the situation even worse).

Quite honestly, the present equal tempered method of tuning is very imprecise, and is at best a compromise, the same as is the case for the piano. This is why for someone who makes similar demands of their instrument, there will be interest in these alternative intonation methods. This makes me inclined to go the route of experimenting with a fretless instrument, or a graduated fretting design - but one then needs to be able to afford the luxury of several instruments upon which to experiment, whereas I have to sell one instrument in order to afford another. But I feel that the onus is upon the designers and manufacturers like yourselves to come up with a viable solution. We as musicians should not have to worry about such things, so we can just get on with making music with correct tonality, and not have to worry about dissonance between instruments like the piano etc.

I might add that I am meticulous about tuning, using at least three ways to cross check, yet more often than not, once I play chords, I find that they are not in tune, and to my ears the bass E and high B are never in tune.

Kind regards,

David

I hope this will pique someone's interest here, and if it is not a suitable place for this query, then perhaps someone could suggest an alternative forum or another part of this forum.

Thanks,

God bless

[Mattia]

Well, I don't know what luthiers you've been talking to, but almost every single one I know recognizes the importance of compensation for tuning. Just like compensation at the bridge affects all notes, especially fretted, compensation at the nut has an effect on notes other than the open ones.

All Buzz Feiten and Earvana have done is patent their own specific offsets for intonation; look at mimf.com/nutcomp for a no-royalties-necessary nut compensation system. Also realize that you can get perfect intonation on a guitar...but microfretting schemes only work for one specific key. Not good. Quite a bit's been published on this in places like the GAL quarterlies, etc. Many guitar companies (like Taylor) have nut compensation in their fingerboards as well, if you measure it.

Also, look at ryanguitars.com, under info, or articles or something for a better way to actually tune your guitar, harmonics bad, open to fretted comparisons? Also bad. Mike Doolin's also written a great article on intonation:

http://www.doolinguitars.com/intonation/intonation1.html

As with almost everything in the guitar world, there's very little innovation, and very little that hasn't been tried already.

[GregP]

Those loothiers(sic) need to brush up on their physics. Compensation is used to help alleviate the problems caused BY fretted notes. If you weren't fretting notes, you wouldn't need compensation.

[rhoads56]

I would RUN, not just walk, away from a loothier (tm owned by GregP) who isnt willing, or simply doesnt understand the basics of compensation and its effect on intonation on guitars. It presents a basic lack of understanding on fundamental design faults. If they cannot understand, or have not figured out how to easier rectify these idiosyncracies (which are not discussed often around here, but they are certainly not 'secrets'), then i would suggest their knowledge may be lacking in other important areas.

[rhoads56]

I have been in touch with my luthiers regarding this issue, and they state categorically that any benefit derived from the Buzz Feiton and Earvana systems is lost as soon as you play a fretted note.

this, is quite literally SCAREY. It proves to me, that they have zero knowledge of the 'intonation basics'. The entire POINT of the Buzz Feiten and Earvana systems is to effect the fretted note, VERSUS the open string note.

[Truth_David]

I have been in touch with my luthiers regarding this issue, and they state categorically that any benefit derived from the Buzz Feiton and Earvana systems is lost as soon as you play a fretted note.

this, is quite literally SCAREY. It proves to me, that they have zero knowledge of the 'intonation basics'. The entire POINT of the Buzz Feiten and Earvana systems is to effect the fretted note, VERSUS the open string note.

Hi, thank you, all of you who have replied. I tend to agree, and it is really a shame given the quality of their workmanship. I have a tiny travel guitar made by them, a Brook Bovey (Brooks Guitars, UK) that literally knocks spots of Taylor's Baby Taylor and other makes too, and that is after having been repaired when it had been very nearly destroyed in transit to Spain from the UK.

But anyway, this intonation issue is something I take very seriously, and sadly they seem not to agree to research any further into the matter. But I am still unsure as to which of the main three nut replacement manufacturers to go with. Each of them has their own marketing hype. Earvana's stuff states that it is better than Buzz Feiten's system, the guys at Enut claim that their intonation compensation is better than any other...and Buzz Feiton claims a guitar that is in tune all over the neck.

I need to iron this out before ordering the parts for my project guitar from Warmoth, as I can get the Earvana nut from them at the same time.

I just checked out that link - wow!!!!! Steve Delft was the first luthier I ever got to work on one of my guitars! That was about 30 years ago, and his knowledge was already awesome...he had a workshop in London at the time, in Stepney if memory serves me correctly. I was doing some unspeakably repulsive modifications to a beautiful walnut Gibson SG Standard, and he helped me! I am too ashamed to go into any more detail, but you know what teenagers are like when they get their hands on their first real electric guitar and want it to be like the one their guitar heroes play?

Anyway, his article was excellent and very helpful. But from what I can see, if I were to buy the Earvana nut and use Steven's compensation, it would save a lot of guess work and messing around, not to mention money .

BTW can anyone please offer me advice on pickup choice? I have an Ibanez US Custom Prestige, with HSH configuration and a mahogany body with flame maple top and Floyd Rose licenced trem.

But now I find that for the type of sound I am looking for, my heavily customised Tokai Strat with a re-profiled 80's custom Fender Strat neck (22 frets) and cheapo noisy S/C pickups, and RMC piezzo/MIDI bridge actually works better. I use a Pod XT and a Hartley Thompson stereo amp. I find that I can get very close to the Holdsworth, Scott Henderson type of sound. But what I want is the kind of sustain that Larry Carlton was getting in the '80's with his Valley Arts Custom Strats, and Eric Johnson's clean sound (as well as the quasi-acoustic piezzo sound from the RMC circuitry).

The idea for my project guitar is to build the guts of this guitar into a Warmoth hollow body (I have yet to decide on the wood, but aesthetically what I like most is the Mahogany with quilted maple top) I will go for a Gotoh Wilkinson licenced trem if I can replace the bridge saddles with the RMC ones, and there is an option for a contoured heel, like the IBZ, and a carved top. If that works, then I will have to sell the Ibanez to recoup the financial outlay....

The chambered body will make the response and resonant qualities of the instrument very similar to Allan Holdsworth's Carvins, and no doubt it will also be a great deal lighter than the Tokai body, which is absurdly heavy compared to the IBZ. But I realize that I am bound to loose the brightness that I can get now.

I am very into Jazz and Fusion, but I also enjoy the Blues sounds, and actually prefer the clarity of single coils, especially in a side by side comparison with the IBZ USA pickups.

But I have to also decide upon the routing options, front or back. As I intend having 3 single coil or stacked humbuckers in the same format, and intend also mounting a Sustainer from the forum designs either on top of the neck pickup or in front of it, I can't decide whether to go for the same setup I have now - a near standard scratch plate with the jack converted to provide an extra pot and switch for the RMC circuitry - in which case it would make sense to go for the universal rout option, or try and do away with the scratch plate and try to mount all the controls and additional circuitry from the rear and have the pickups set directly into the wood so as to avoid vibration from the Sustainer driver.

I would appreciate your thoughts on this project....

Thank you again

David

[rhoads56]

Without a doubt, forget the "big brand" nut solutions. They are a stop gap and arent fitted for your choice of string guage, action, or scale length. For true intonation, the nut must be compensated to each guitar... no two are alike (although close). The big brand products are designed to be retro fitted to suit given guitars, with their bridge locations as standard. I know myself, when fitting a compensated nut to a custom guitar, i modify the bridge position slightly to allow for the saddles to still be half way within their rang, AFTER its correctly intonated. Of course, this is purely for aesthetics, and the saddle location on the bridge has no audible difference (just looks crappy when they arent roughly central). With an accoustic instrument, this bridge location at manufacture is CRITICAL to having the intonation work out well.

If you are having a guitar made, the extra cost would be insignificant. I use a template to rough machine the nut, and then shave it down to suit. Every change at the nut requires a change at the bridge. It takes about 4 hours max to get it perfect, but often a lot less. Ive probably done 150 compensated nuts, but only for about 50 clients. Every single one of them has returned within a few weeks to get all their other guitars modified to suit, the difference is that noticable.

[GGW]

For the first guitar kit I made, I bought an Earvana nut and it made a big difference. Open chords have always had a "sour" sound to me and this cleared that up. I can check up the neck and everything is fairly in tune. I say "fairly" because as pointed out, there are still variations in how a note is fretted. Next, I built a guitar from scratch and I carved the nut using a combination of the Earvana nut shape, the http://mimf.com/nutcomp/ site, and my own experiments using a wedged shaped piece of wood. It took a long time, but I carved a nut that gets me in tune all the way along.

I've reasoned it out like this:

First you tune the open string with the tuner; it is in tune. When you fret note 12, it is probably a bit out due to the fact that the string had to stretch a bit to be pushed down to the fret. Next you compensate at the bridge to adjust for the 12th note fretting effect. Now the open note and the 12th fretted note are in tune. The 12th note, however is in the middle of the neck, so it is the one played with the least amount of stretching. The most out of tune note at this point is fret #1, followed by #2 with the effect diminishing rapidly after that. When you play fret #1, you bend the string down to the fret at the sharpest angle and so stretch the string the most. We don't play up to the bridge so that end doen't count. To compensate for this, you move the nut closer to fret #1 to lower the pitch by the amount that fretting the note sharps the pitch. This in turn causes a slight adjustment in the tuning and bridge compensation that averages out the first few frets.

Does this make sense?

[SwedishLuthier]

The Earvana nut is my preferd solytion and I put it on all of my own guitars and on most of the guitars I build for others. They can't do the impossible. They can't make the guitar sound perfectly in tune for any not played in any scale. That is simply not possible for a guitar. But it is much better compared to an un-compensated nut. Other benefits with the Earvana system is that it is retrofittable compare to the versions were the fret board is cut of like the Buzz Feiten (OK,Perrys nut looks like it is possible to remove without damage and there are a shelf nut availible for the BF system...) . Furthermore the Earvana sytem can be adjusted for other string types by the player himself without other tools than those used in a standard set-up. And I don't have to pay like 250$ or something like that (they don't list the price of the entry level training package anymore) for a DVD and a shelf nut to be able to offer that as an option.

[Truth_David]

Without a doubt, forget the "big brand" nut solutions.

Hi Perry, thank you for this information. Are you including the Earvana system in the 'big brand' nut solutions? I ask that because being the only nut that is screw adjustable, retrofittable and affordable, it seems like a fairly good option. Stephen Delft's instructions are not clear enough for someone who is only capable of dabbling in home setups (and he says as much in the article). I am capable of setting up my intonation and other basic maintenance, but have neither the necessary skill nor tools nor quite honestly the time and patience to go through the painstaking trial and error process he describes - I am a musician, not a tech.

And here in Spain it is not like being in the UK, where one can go to London and other places and find in-house techs in nearly every guitar shop who are capable of such work. Here you are lucky if you can find one or two in the entire country, and the only one I have found who does such work only does the Buzz Feiton setup, and must of course charge big bucks for the service.

I also cannot afford to put this guitar out of commission, at present I am only committed to playing in a worship group for my church, but that involves three days per week - two services and a rehearsal. As I have to sell my Ibanez, I only have my Strat as my only other electric (which is going to serve as the basis for my project), so this has to work quickly, or it will have to wait....

God bless,

David

[rhoads56]

My understanding was that you were commissioning an entire custom guitar??

Im sure in Spain, there are HUNDREDS of luthiers. From my understanding its a meca.

If you have a tight budget, and a DIY attitude, then the earvana is definately a good product. A standard nut is a honda. An earvana is a mercedes, but the compensated is the lamborghini.

[Truth_David]

Also, look at ryanguitars.com, under info, or articles or something for a better way to actually tune your guitar, harmonics bad, open to fretted comparisons? Also bad. Mike Doolin's also written a great article on intonation:

http://www.doolinguitars.com/intonation/intonation1.html

As with almost everything in the guitar world, there's very little innovation, and very little that hasn't been tried already.

Well Mattia, thank you. I finally found time to read through both articles entirely, although a little hastily. What has been the most practical for me has been the fretted to harmonic tuning from the ryanguitars article, and the advice to tune via the A5 and E5 chords from Intonation V on the Doolin website.

I found that after having tuned the guitar using the first method, when I then cross-checked using the A5 and E5 chord method, I could only hear one note that was out - the high E (and then only with the E5 chord). Probably because I was tuning an electric without amplification, but when I then tried playing some jazz chords, I found that they were much more pleasing to the ear than before, and I just tried the m7+ chords again, and they too sound much better. It might be due to having less 'beats' occurring, but there also seems to be less resonance between the notes of the chord. They are actually beatless, and that seems to detract somewhat from the quality of the sound. But this is always going to be a compromise

Now one problem that arises is that we all know that a guitar can be in tune with itself and sound great on its own, but once you are in a situation of playing alongside a piano for example, that is a different scenario altogether, and dissonances are to be expected - it will be interesting to see whether the compensated nut actuals worsens the situation.

Neither article however seems to address the actual application of the nut compensation sufficiently to allow me to attempt to perform the process on my instrument, certainly not with any degree of confidence. I hope that if I purchase the Earvana compensated nut and intonation reference, that this will provide all the necessary information.

Thanks again, and God bless

David

Edited January 16, 2007 by Truth_David

[rhoads56]

but once you are in a situation of playing alongside a piano for example, that is a different scenario altogether, and dissonances are to be expected - it will be interesting to see whether the compensated nut actuals worsens the situation.

It makes it MUCH MUCH better compared to pianos, and keyboards.

[Truth_David]

My understanding was that you were commissioning an entire custom guitar??

Im sure in Spain, there are HUNDREDS of luthiers. From my understanding its a meca.

If you have a tight budget, and a DIY attitude, then the earvana is definately a good product. A standard nut is a honda. An earvana is a mercedes, but the compensated is the lamborghini.

First of all, I'm not commissioning anything. I am rebuilding an already existing electric guitar which I described above with Wormoth parts, which I have to order direct from the USA.

Secondly, there is a somewhat backward mentality in Spain toward anything other than the Classical or Flamenco guitar. Electric guitars are very common, but very few technicians are to be found outside of Madrid and Barcelona who have the skill, knowledge and interest in anything even slightly esoteric. Steel string acoustics are not well accepted in this culture outside of one particular part of Northern Spain, where there is a strong Celtic influence.

As I explained, my Strat has an RMC piezzo/MIDI system built in, and there is no-one here who will even touch the electronics. That is why I have to do it myself. As I mentioned, there is only one luthier on the Internet in Spain who advertises nut compensation. No doubt there must be others, but this is a country which has not caught up with the rest of Europe in terms of networking and implementing new technology. Spain is several years behind the rest of Europe in terms of its infrastructure. The technology is available, but few know how to use it. ADSL was only introduced a couple of years ago, and most areas still cannot obtain more than 1MB, to give you an example. You cannot even go out and find something as simple as a 19" rack enclosure - only last year it became possible to find an external USB2 drive case. When I first arrived in 2000 I suffered real culture shock. I had been so used to going down to Soho in London and literally finding dozens of music shops filled with the very latest technology, and had had years of personal interaction with many of the main guitar techs and luthiers. There you are able to get your hands on any of that equipment and try it in the shop. Here you have to order it, because of the way franchises work here. They keep next to nothing in stock, everything has to be ordered from online catalogues that are poorly presented. Add to that the fact that Spain suffers from a truly bad delivery system, and you start to gain a truer perspective of what you call a 'Mecca'.

The Brook Bovey is a separate issue, this a guitar (an acoustic travel guitar) that was hand made by Brook guitars, and the guitar was damaged in transit. I sent it back to them for repair and they returned it with what seemed a very transparent repair, considering the extent of the damage. But a couple of weeks ago, I pulled the guitar out of the gig bag intending to restring it, and the headstock gave way again.

So when I wrote to them about this, they very kindly agreed to repair it again free of charge. Around the same time I stumbled upon the various nut/bridge compensation methods, and wrote to them asking them whether they could adjust the intonation compensation for me while the guitar was there for repair. I posted their reply and my subsequent question to them here, as I was surprised by their reaction, which was simply to direct me to a website which explained the equal tempered system whilst denying that there was any benefit to be gained from any of these systems.

They are a highly sought after lutherie in the UK, and their instruments are really beautiful, and it must be said that the dissonances I noted related more to my Strat than to the Brook Bovey, so it might be that they already employ some nut compensation in the construction process of the instrument. But in any case I cannot check the new tuning information from those articles on the guitar until and unless it is returned to me in a playable condition. It might well not be repairable, as the climatic conditions are so variable in the South of Spain that it might not be possible to find a glue that is strong enough to resist the sudden changes from cold to very hot which can and often do occur here.

The point is that I needed to verify whether their statement was accurate. I am well aware that not only in the field of music but within the various branches of modern science itself, there is a plethora of disinformation and deliberate falsifications, so I can believe that some of these companies are just out to make a quick buck. But I needed also to see all sides of the argument, because my ears tell my that my instruments are not correctly intonated even though they are in tune with electronic tuners. But these do not help with the fretted notes, and as I mentioned, the lighter the strings, the more likelihood there is of exerting slightly too much pressure on the string and thereby sharpening the pitch within a chord. If all six strings are fretted, then this effect will most likely be produced to some degree in all six fretted notes.

Now that is in addition to the fact that the nut might or might not be compensated, and the more my ear develops, the more noticeable this becomes. The fact that there is a tendency to fit higher profile frets these days only worsens this scenario, as I described it previously, it seems to me to be very similar to trying to play a scalloped fingerboard in tune, especially on the first few frets. The tendency is to exert too much pressure - we all do it, especially when playing physically demanding shapes, like Allan Holdsworth's stacked harmony chords.

We need to train our fingers and our ears to a very high degree to be able to play in tune.

God bless,

David

Edited January 16, 2007 by Truth_David

[Truth_David]

but once you are in a situation of playing alongside a piano for example, that is a different scenario altogether, and dissonances are to be expected - it will be interesting to see whether the compensated nut actuals worsens the situation.

It makes it MUCH MUCH better compared to pianos, and keyboards.

Thanks Perry, I am starting to feel more confident about the benefits of the Earvana system. Perhaps you could help me though on a minor issue: There are several versions available for the Strat replacement nut. Aside from the actual dimensions, the main criteria seems to be whether or not it is a vintage curved nut. Well, the problem is that this is a Fender Custom USA neck, and has wide frets, and there are 22. All that obviously belies it being a vintage nut. But, when compared to my Ibanez Prestige s series, the nut is indeed curved, as the locking nut on the Ibanez is dead straight.

But I do not know to what degree the curve on this Fender nut differs from that of a vintage Fender nut, and short of a side by side comparison, I am not sure how to determine which replacement I would need. I could post a photo if you can explain how to upload it

God Bless,

David

[westhemann]

might not be possible to find a glue that is strong enough to resist the sudden changes from cold to very hot which can and often do occur here.

well...i don't know anything about compensated nuts...but there are glues which can handle anything spain can offer temperature wise...

epoxy resin is completely resistant to weather...as is polyeurethane

[Mattia]

might not be possible to find a glue that is strong enough to resist the sudden changes from cold to very hot which can and often do occur here.

well...i don't know anything about compensated nuts...but there are glues which can handle anything spain can offer temperature wise...

epoxy resin is completely resistant to weather...as is polyeurethane

Well, quite. Then again, unless you're building a guitar to withstand actual extreme temperatures (and no, Spain doesn't count), Titebond should be plenty fine. Besides, you should treat your guitar like you treat your own body: where possible, keep it climate controlled.

[Truth_David]

might not be possible to find a glue that is strong enough to resist the sudden changes from cold to very hot which can and often do occur here.

well...i don't know anything about compensated nuts...but there are glues which can handle anything spain can offer temperature wise...

epoxy resin is completely resistant to weather...as is polyeurethane

Thanks,

I have no idea what they used to glue the headstock on last time. To be honest neither can I state truthfully that temperature changes are the direct cause for the repair to fail. But we are talking about a zone where one can find a temperature of 30º outside, and maybe 22º indoors, during the day on a sunny day, then as the sun goes down, the temperature can drop to between 6 - 10ºC within half an hour, and the same applies indoors if we get a power cut, which happens just about every day. So if I am out during the power cut, of course I will return to a house which is very slightly warmer than it is outside, let's say around 12ºC.

On a cloudy day with no sun, the temperature can remain at around 10ºC during the day and drop to around 6ºC at night or sometimes even less.

During the summer, the difference is more like high 40's C during the day to around 20ºC at night (but without heating), sometimes it only falls to 30º. I hate it....

But right now it is mid winter, and the night-time temperatures are still falling. It hardly ever gets to 0ºC or freezing here, but due to the damp it feels very much colder

So we are not only talking about big temperature differences from day to night, but also from day to day. I am sure that a lightweight acoustic guitar will be far more likely to suffer from these rapid temperature changes, especially when it has been weakened at the headstock.

God bless.

David

[Sambo]

If you have a tight budget, and a DIY attitude, then the earvana is definately a good product. A standard nut is a honda. An earvana is a mercedes, but the compensated is the lamborghini.

Don't lamborghini make more tractors than sports cars?

Sorry.

S

[Mattia]

If you have a tight budget, and a DIY attitude, then the earvana is definately a good product. A standard nut is a honda. An earvana is a mercedes, but the compensated is the lamborghini.

Don't lamborghini make more tractors than sports cars?

Sorry.

S

Well, the tractors probably outlast most person moving motor vehicles

Re: temperature swings: that's dead-on normal for most of europe, and very much in the safe zone for any common woodworking glue. Little different to the temp swings in Italy, and my guitars there have survived without any problems. Relative humidity is more of a factor than temperature (although the two are linked), and even then, it's more about the thin plates of wood in acoustic guitars moving about than it is about glue stability. If your top isn't warping, cracking or otherwise deforming, I doubt your neck would be having trouble.

[SwedishLuthier]

[Truth_David]

Thanks Perry, I am starting to feel more confident about the benefits of the Earvana system. Perhaps you could help me though on a minor issue: There are several versions available for the Strat replacement nut. Aside from the actual dimensions, the main criteria seems to be whether or not it is a vintage curved nut.

[soapbarstrat]

What can a person get away with, when making a "compensated nut", without having to worry about getting sued by the "patent holders" ?

[Mattia]

What can a person get away with, when making a "compensated nut", without having to worry about getting sued by the "patent holders" ?

Because nut compensation is centuries old, and very common? And, in fact, an essential part of making a guitar a guitar?

The various patent holders have patented their particularl brand of nut intonation, not intonation adjustment at the nut per se.

[GregP]

The only way you could violate Feiten's patent would be to use his exact calculations which relate to his calculations of "ideal" compensation (at nut and also at bridge I believe) based on each string guage at a particular pitch, with the common scale length, PLUS his customized tunings which do not stick strictly to even-tempered tuning as per most machines. You can get the "Feiten" tunings for Peterson Strobe tuners.

Other than that, the idea itself is not and cannot be patented. As with most patents, Feiten and Earvana's are based on a "significant improvement to a product or process." But they can't patent the original idea itself, in this case.

Greg