For "i want use one speaker" I mean bridge it like first image, if is not too much complicated. If it is too much complex i only wanna use only one channel at time but drive only one speaker.
I've found a more resolution schematic (2nd image) and first stage is only the EQ.
So, I hope in weekend I found some time for try to connect guitar and a speaker and try it.

Hello, I want to modify this amplifier that i bought in a flea market into a Guitar amplifier, is a full germanium transistor, that work at 9/12 volt . Is stereo so i'm thinking about use One Channel for high input and one for low, but i wanna drive only one speaker. Can help me for modification? Tnx

 :tu: thank you very much

  :dbtu:tnx

Hello, if I wanna sobstitute power section of this schematic,with a IC poweramp, what part of circuit i've to "remove"? (I not think is all things put after R10)
tnx in advance

Hello, if i will reply this Airline Valco Amp, what kind of transformer i need(46volt and how much ampere)? and someone had a suggest for replace old transistor(40409/40613 and 2n297A)  that are hard to find and/or too much expensive? tnx in advance

I not think to use amp out of house so i put a fuse ti be more safety but I put a power transformer 200 to 12 500mA or 1 A

inviato e basta

Tnx J M Fahey. :tu:
Ok, this is my final idea...in this weekend I hope to go buy components, i made it on breadboard and after i think to solder it in perfoboard. :dbtu:
I've marked R13 because in schematic not have value, I've put it 1 in my schematic on multisim...is correct?
The same for diode 752, i've put 1n752a...is right?  8|

So I've thinked a lot about that you say, and beacuse is my second work I not will complicate too much mi life :lmao:
so this is the next idea
one 12v simple power supply and this simple 2 transistor preamp, preassembled power stage.
So the question, where to put tone stack? I prefer a simple one knob stack...ideas?
mpf102 have nice clean sound suitable for jazz?

Finally i've design first circuit, i put tda2030 because in my multisim there isn't tda2050...but for power amplifier I will use a ready to solder kit...
please can check if seem all ok :tu:
Thanks guys for help

Ok , let the tones as they are not much 3 potss and a handful of resistors and capacitors that make the difference ; )
In fact I thought to build me this amp to study , because I'm about to start a course in jazz guitar for beginners .
Then I'll know that speaker give me from my wife for Christmas.
But i will add a little overdrive like "electra distortion" or trotsky drive

I'm working about electrical scheme...when I've do it...I'll post here

Ok, this can be final prototype....
What you think about simple Tone control...i will do a similar to this
and this is the drawing...sorry if i do this in paint

 :dbtu: Great!
Thank you very  much!!!!!!! :tu: :tu: :tu:

Hello,
tnx for helping, "Nuova Elettronica" mag, from azines is not more in publishing from mid 2012.
I've only found this kits:
http://www.ebay.it/itm/Amplificatore-TDA7294-80W-in-Kit-da-montare-/131597756420?hash=item1ea3d66804

http://www.ebay.it/itm/Scheda-Amplificatore-mono-70W-TDA7294-DIY-KIT-MONTATO-/271983979669?hash=item3f53822c95

Other I find have less output...from 1 W to 7 W :duh

So i not use this amp with all current they need, so i think with 24v is less power...
For my amp i've a 30 watt 8 ohm speaker 8 inch.
Tomorrow i design the prototype scheme  8| and post here

Thanks, you mean some like this?

inviato e basta