Balanced Input Stage

[Bukitoo]

HI !!!!

I have a question for U guys.
Maybe you tried these solutions and want to share your experience.

I was looking for solutions for building my own guitar preamp, but I get to many "strutures".
One of them is the instrumentation amplfier. Another is using a differential pair as input.

Others solutions use a couple of transistors in many configurations.

I was wondering wich of those introduces less noise and distortion. Im very newbie

Thanks in advance !

 

[Nelson Pass]

If you want the ultimate in rejection, RF proofing, isolation
and so on, check out a Jensen transformer. You can find them
on Google, and they're in Hollywood and are very nice people.

 

[till]

building my own guitar preamp

the input stage of you guitar amp, or a little preamp inside the guitar?

 

[Bukitoo]

I just try to design an external preamp.
But many posibilities!!

 

[dalbjerg]

First of all, it’s ok to bee confused.
I can understand that you have been looking at some “Instrument” amplifier circuits.
Those are not for music instruments. The name come from laboratory equipment and is often used in the input stage of measuring instruments.
For electrical guitar you use a singe-ended (“normal”) input and not a differential.

You should post your question in the Musical Instruments forum.
Here are a few good links to start building your own amp-
http://blueguitar.org
http://www.diyguitaramp.com
http://sound.westhost.com/projects-5.htm

If you can’t join them beat them.

 

[GRollins]

Oddly enough, you don't want a low distortion circuit for a guitar amp. The trick is to have enough of the right kind of distortion. It's not the same set of requirements as home audio.
Note that all the solid state pieces try to sound like tubes. All the classic amps, Vox, Fender, Marshall, etc. are tubed. The one exception to this is that sometimes a "clean" sound works well for bass. Never for guitar.
It's been a while since I've pawed through his archives, but Ned at www.triodeelectronics.com used to have a wide assortment of schematics, including guitar amps. Most if not all of them will be tubed, but they can give you ideas for topologies.
If you're wanting to go solid state you're going to be using a lot of opamps.
If you search the web, you can find schematics of various amps, although you'll have to go to a dozen different places to get a good overview.

Grey