dori2o

You could simply connect the battery to both, the preamp draws very little power, but the "ruby" will drain the battery fairly fast and tends to get fairly distorted as it drains down. If you use a regulated power supply on it, it will sound better of course. The speaker has a lot to do with it too...a tiny computer speaker won't sound too good, but a larger one can sound ok.

If you can build this, you have virtually built the sustainer circuit

pete

The idea is to power the amp via a 9v adaptor, so as you say it should sound better from a regulated source.

The plans for the Ruby suggest a 4ohm speaker. Would an 8ohm speaker not be better?

(Not meaning to sound thick, but what is a sustainer circuit?)

You can run the two circuits from the same supply...the tillman and the ruby are very basic...and would work as well as the fetzer/ruby that most use for sustainer circuits. The problem is that these amps are incredibly low powered and tend to distort, typically for any kind of decent acoustic sound you would need an amp with a lot more headromm and more than a simple battery can supply. You might consider something like this for headphones. You may also get away without the preamp if there is already a preamp in the guitar...perhaps a little more detail of what you are seeking to achieve might help

pete

I've got a squire acoustic that I have inserted a piezo pickup into, The sound is very 'Tinny', and I've run it through a preamp and it improves the sound 10 fold.

I want to make a small practice amp that I can use in the house.

If I wanted to make something a little more powerful, could somebody please reccommend a good amp schematic.

Also with the idea I've had, would I still need to run the seperate curcuits to have their own power supply i.e. a connection to the power supply from each circuit, or would I put the power through the preamp and just connect to the amp and let the power filter through?

I want to make an acoustic amp using a simple preamp circuit and the Ruby from runoffgroove.

Both requires a 9v power input.

Question is, can I simply link the 2 power inputs to the same lug, or will both circuits require their own seperate power supply.

Secondly, is there a circuit I can make that will do the job for me instead of having to do it as described above.

(Here is the link to the preamp)

Preamp

What stage is the guitar at...has the top been put on...are there f-holes or similar to get inside? What kind of bridge...any chance of a pic?

pete

The guitar is not yet whole, i.e. the top is not yet on it.

The bridge is a standard 12 string bridge as below

Well then, here in the UK I've been unable to source any piezo cable, or Piezo film tabs to be able to make an under saddle transducer. So plan B.

The guitar I'm making is a semi hollow body acoustic, it is topped with a 6mm veneer top glued to the body on which the bridge will sit. The strings are being passed through the body via string ferrules.

So if I was to rout out beneath the bridge approx 3 or 4 mm rourhly the size and shape of the piezo disk and attach a piezo disk to the veneer beneath the bridge, would this be sufficient to pickup the sound?

This would then be fed to the onboard preamp, jack etc.

That is awesome,thank you very much.

Well the guitar body is well under way now and is on the subs bench until the neck is part done. To progress the project I need to work out the string spacing. I'm looking at a NUT width of 48mm, but I have no idea what the string spacings should be, not only between each main string, but also between the string pairs.

I can't make the saddle/bridge until I've calculated this, or found the answer.

I've looked through google and on some of the manufacturers websites but there is nothing there.

Can anyone please help me?

Cheers

dori2o

It's not a piezo disk/buzzer, it's an under saddle pickup. Like this

Under Saddle Transducer

This wire was suggested to me on another forum but I'm not sure if it's correct as the instructions talk about pvdf piezo coax cable?

I'm looking for some piezo cable in the UK, and the only thing I can find is this

Coax cable

Would this be suitable to make the under saddle piezo?

Thanks that is a start. I'm in the UK by the way.

I have some knowledge of electronics, but it was some time ago when I did my appenticeship in engineering, and I can read a schematic quite competently, so wiring/soldering etc isn't a problem.

The guitar itself is essentially solid piece of ash cut into the guitar shape, with sound pockets and wiring channels routed out, covered with an Oak veneer on the front (to cover the sound pockets and routed channels for the wiring), and a clear varnish or whatever on the back. 12 string neck and headstock handmade from maple stock.

I do like the slider pre amps, but they are too big for the body of the guitar, hence why I was thinking of gutting one.

I don't really want to go down the route of using coil pickups cause I want the guitar to look like an acoustic, I dont want pickups on show. Unless someone has an idea on how I could use a hidden single coil/humbucker pickup?

I was hoping to make an under saddle pickup from piezo cable, not really sure if an under bridge piezo disk would work as the veneer is approx 6mm thick.

Regards

dori2o

As the title suggests I need help with the piezo pickup for my homebuild semi-hollow acoustic. I want to add volume/tone controls. can anyone advise how I can do this, provide a schematic, wiring diagram etc?

Do I have to make a circuit? or can I put the volume/tone pots into the circuit without one?

Will it need a power source? 9v battery?

Is it cheaper to but a preamp and gut it?

any and all help appreciated, build is on hold until I can figure this out as I need to know what pockets/channels need routing out of the body.

Many thanks in advance to anyone who can help.