Welcome to Solid State Guitar Amp Forum | DIY Guitar Amplifiers. Please login or sign up.

May 28, 2024, 02:03:37 PM

Login with username, password and session length

Recent Posts

 

Converting audio amp to guitar amp

Started by Vitrolin, April 06, 2010, 04:40:58 PM

Previous topic - Next topic

J M Fahey

Hi bassbuddy.
Even better, because PA power amps are beefier and meant to be cranked all night, either by a band or even worse, by a DJ.
Home stereo power amp sections *can* definitely put out the specified power, no doubt, but do not expect 8 straight hours, full tilt, non stop, because that's unrealistic in any home, unless you live in the middle of a desert or forest.

Bassbuddy

Hi
The idea I meant was not using a PA amp but to build a separate preamp in such a way that it can be combined easily with A power amp to make a nice matched couple. I will attach pictures of my amp to show what I mean.
GG

phatt

Quote from: Bassbuddy on April 12, 2010, 01:05:06 PM
Hi
The idea I meant was not using a PA amp but to build a separate preamp in such a way that it can be combined easily with A power amp to make a nice matched couple. I will attach pictures of my amp to show what I mean.
GG

Plus 1 from me,,, Your's looks a bit neater than mine :)
Yes at my age you don't give a rats A what it looks like,,, it just has to sound good.
Cheers Phil.

Vitrolin

Quote from: Bassbuddy on April 12, 2010, 01:05:06 PM
Hi
The idea I meant was not using a PA amp but to build a separate preamp in such a way that it can be combined easily with A power amp to make a nice matched couple. I will attach pictures of my amp to show what I mean.
GG

this is what greg ginn of black flag uses, in the old days he plugged his guitar directly into the PA amp and turned up the volume until he reached enough distortion...

yours is looking very good

Bassbuddy

Hi guys

Phil, you're speaking right from my heart. When I was younger I spent a lot of effort to make things look good. I quit with that nonsens.

Here is another picture of the interior of my preamp. I built a modular system to be able to use it as a kind of testbed.
From left to right you see the high impedance input amp, the second stage with gain control, a 5 band equalizer, the (optical) compressor and the last amplifier stage with soft clipping.
The DIN plugs are used for interconnection of the stages and power supply connections. This way I can easily replace one of the stages by something else. Apart from the equalizer I developed each stage myself.

UsuallyI use the amp with two of these cabinets.

Friendly greetings from the Netherlands
Geurt


Bassbuddy


phatt

Hey Bassbuddy,
Very tidy inside, for a home job that would have taken a lot of time and effort.

My Laney rig is just for convenience,, only 35 watts.
I have a massive 120watt Poweramp for bigger stuff but I hardly use it as the gigs I do are only small.
Handy to have more than one piece of gear in case something goes down.
Phil.

J M Fahey

That's quite a professional job, congratulations.

JonnyBlade

That's the one short coming of bread board.
If you want something to work 100% trouble free, you have to put it in an enclosure with enough room for 100X the amount of circuitry you've actually built.

Great work though, very clean build.


phatt

Yeah but at least he can change a component if he needs to  8)

Try that on a double sided suface mount board :P

Wait till you youngens get past 50 and you need glasses. :lmao:
Phil.

Bassbuddy

Hi folks,

Even worse, I need two pair of glasses for this kind of work. My colleague nicknamed me "Mister Six-Eyes".

A long time ago I took the trouble to design and make PCB's. I quit that because all my designs are one-off product. Breadboards are ideal for this purpose. Reliable, rugged and easy to modify. As said I use the thing as a kind of testbed for my designs. In this case changing a component mostly means changing a module. The cabinet by the way was made of an old cassette-deck I had lying around.

But to come back to the root of this topic: I am sort of kidnapping it. The idea was to give Vitrolin an idea how to solve the issue of converting a HI FI amp to a guitar amplifier.

GG

Bassbuddy

#26
So a resumè:

Yes you can convert a HIFI amp to a guitar amp.

- My idea is to build a separate preamp with everything inside to:
- Increase the input sensitivity if necessary. Give the guitar input a high impedance.
(Take measures against RF disturbance. This is an issue with sensitive, high impedant inputs.)
- Make the output of the preamp deliver a signal that is suitable to drive the AUX, CD, Radio or whatever input of the HIFI amp you wish.
- If you want to overdrive the amp, do it in the preamp and not in the HIFI amp. This way the HIFI amp will live longer and you can manipulate the character of the overdrive to sound the way you want. Also you can use the overdriven signal at lower volume levels.
- Build the finished preamp and the entire HIFI amp in one cabinet for easy connection, transport and for protection against the rough life on stage. Realise that HIFI amps are mechanically not designed to be dragged about. It also makes it easier to swap the HIFI amp if you decide to use another one.
GG


Vitrolin

thank you all for your help, unfortunately ive have no time nor monety to realize this project at the time but it will happend and then ill post the result