Print Page - Bass Amp Head from power amp:

Title: Bass Amp Head from power amp:
Post by: Arn C. on May 28, 2004, 12:51:47 PM

I have an old power amp from Audimation corp, S. Plainfield , NJ

120v 50/60 hz 3amp max
4a 125v fuse
(What do you think the output watts is?)
It has 4 output power transistors T03 package No numbers on them, no numbers on the huge power transformer. It has a few tropical fish caps, so it is fairly old.

I measured the dc volts of the two large filter caps +37 vdc and -37vdc,
I know I can lower these voltages for the preamp if necessary.

I would like to put a preamp in the same box, lots of room. Just wondering what I should use for the front end. I am making a bass amp head out of it. Any input would be grateful! I don't want something too complicated, but I do want a good sound for the bass.

Thanks!
Arn C.

Any suggestions?

Title: Bass Amp Head from power amp:
Post by: Gringo on May 28, 2004, 01:23:11 PM

Hey Arn, have you seen this one?

http://www.albertkreuzer.com/electronics.htm#preamps

Take care! :)

Title: Bass Amp Head from power amp:
Post by: Arn C. on June 01, 2004, 11:07:49 AM

Thanks Gringo!
Anyone else have any ideas, I really don't want it to be too complicated , just want a nice easy clean bass preamp.
Thanks again!
Peace!
Arn C.

Title: Bass Amp Head from power amp:
Post by: smoguzbenjamin on June 01, 2004, 11:25:27 AM

I'd say a FET buffer, then a FET or opamp gain stage to compensate the volume loss of the tonestack that comes after it, another buffer and into the power amp. Something along those lines should do great. :)

Title: Bass Amp Head from power amp:
Post by: Arn C. on June 02, 2004, 07:32:23 AM

Thanks Smoguzbenjamin for your suggestion!
Peace!
Arn C.

Title: Bass Amp Head from power amp:
Post by: Kleber AG on June 02, 2004, 10:56:16 AM

Hello Arn...
If you really want SIMPLE, but still powerfull this is a great tool I've been sucessfull using over an year now:
http://www.geofex.com/circuits/Adjusticator.gif

If you want you can start with simple buffer at input followed by a tone stack that you like and then feed this amazing circuit...

It'll provide lots of volume and really drive your power amp well.

Another :lol: cool feature of this circuit is that you can plug straight to the speaker cab (in my case 4x12) and have nice practice amp for bedroon levels, for me it's so loud for home.

Thanks RG for this powerfull circuit (simple) 8)

Hope it helps...
Kleber AG

Title: Bass Amp Head from power amp:
Post by: Lonestarjohnny on June 02, 2004, 11:20:08 AM

Arn, Why don't you pick out a Bass amp that has the EQ that you think would be useful for your style of playing and take the ROG way and put a J-Fet preamp in it, say like a Fender Bassman, or an SVT ampeg, or whatever, maybe 2 or 3 Emulater's on the front end with a footswitch controlling all 3 or 4, the sky's the limit if you have plenty of room.
JD :idea: :idea: :idea:

DIYstompboxes.com

DIY Stompboxes => Building your own stompbox => Topic started by: Arn C. on May 28, 2004, 12:51:47 PM