Solid State Guitar Amp Forum | DIY Guitar Amplifiers
Solid State Amplifiers => Tubes and Hybrids => Topic started by: Minion on February 28, 2009, 12:56:14 PM
Hi Folks, I just wanted to post my latest Guitar amp build for you guys...
It is Parts DIY Kit, Part Consumer gear and part Totally DIY...
It is a 100w Head , it has a Fet opamp front end driveing a 12ax7 Tube preamp with speaker simulators and Ballanced DI Output and effects loop and polarity switches and some other features (it is a Modded PAiA Kit), it has a 15 band EQ with High pass/Low pass and Notch filters , and a 100w DMOS Output stage....
(http://i13.photobucket.com/albums/a300/mr_sevs/DVC00361.jpg)
It sounds Freaking awesome , especially for a heavey sound , lots of Harmonics ....
Cheers
Thats just sick! Looks like a complicated build. Gut shots, please?
I can"t really post guts pics as I would have to take it appart and it would still be difficult as there isn"t really any room with the pannels off to get a good pic but I could post some schematics...
Here is a schematic for the preamp section...
http://www.paia.com/prodimages/siabsch.pdf
I used fet input opamps and configured it for 10x as much gain than as shown...
the EQ Section is actually consumer gear that I integrated into the unit...
For the Power amp section I used a TDA7293 100w Mosfet Power amp IC , it is the same curcuit in the data sheet under "Figure 1" .....
http://www.datasheetcatalog.org/datasheet2/9/0ozxelyhtgfl5jsx9108fj3sqq3y.pdf
The Preamp runs off of a 12v Power trsnaformer (the Tubes run off of a CMOS Hex inverter to ramp the plate voltage up to 45v dc)
The power amp section runs off of a 2x28v 200Va power transformer giveing me 2x42v dc and has 20,000uF of capacitance per rail (40,000uF total) and uses a 15a Bridge rectifier.....
the amp has a bit of turn on thump but is increadably quiet for a high gain amp (very little humm).....
Cheers
Congratulations, very interesting amplifier.
When possible post some clips.
Bye.
J M Fahey