Simple amplification stage

[plunderpot]

Hello folks!

I have a pedal that I've built that allows me to send the signal from my acoustic guitar into my electric guitar chain.  I'd like to boost the signal from the acoustic guitar to match the electric guitar signal.  Does anyone have a suggestion for the simplest amplification circuit to do this?  It doesn't have to have great fidelity (the idea is for it to be affected), but I'd love a low part count and small size.

Any ideas?

Thanks!

J

[frequencycentral]

EH LPB-1

I built one on a pieceof perf 8x7 holes.

[Faber]

Yeah, the LPB-1 is a great little booster!

[frequencycentral]

I recommend a BC547 for the transistor - more gain!

[demonstar]

Anything with a single transistor gain stage is good.  A single common emitter stage or common source stage should do the trick. How much gain do you need? Are you wanting to use an existing circuit or design your own?

[Gus]

First does the guitar have a built in preamp?  If it does not piezo pickups work better at greater than 1 meg, 5 to 10 meg might be better

Now simple and clean and adjustable gain.  Use a FET input opamp TL07x or Lf35X or. 

I would use a a 1/2 battery splitting say 22K and 22K and cap at the center.  Use  2.2 meg one end to the divider and the other to the + input then use a  .01 input cap(cap not needed if direct to a piezo element) input to the + input
The opamp - input a say 10K and 47uf cap to ground.  Output to -input a 100K pot wire as a variable resistor.  Then
a coupling cap and a 100 ohm resistor in series at the output
I would also use a cap across the battery

Google non inverting opamp circuit and things like that.

LPB has a low input resistance and maybe to much gain.

[plunderpot]

Thanks so much everyone...

The LBP-1 sounds like a great way to go...  Any suggestions on where to look for a perf layout, or?...  I tried searching but maybe I'm not doing it well...
(so many ellipsis - it's late...)


J

[Barcode80]

i have a vero that you can convert in my gallery. just treat all strips as nodes. search for barcode, then choose my vero gallery. tiny layout.

[plunderpot]

Sounds good - maybe this is a good chance to give vero a shot.  Thanks Barcode80.

I'll update on how it goes...

[Dragonfly]

I would tend to agree with Gus.

A fet based op amp would probably be ideal.

If you only need a little gain, however, the Tillman preamp is excellent, compact, simple to build, and works well with piezo pickups. Much better than the LPB, IMO.