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previous: Bryan James here are some pics of a power amp i... -- 5/17/2000 1:42 AM

Re: pics

5/17/2000 5:24 PM
MBSetzer	Re: pics Hi Bryan: Looks excellent to me. I assume you are using 12AX7 and 6BQ5 tubes. The schematic is nice too, but if someone was to try and duplicate your amp it would help if you cluttered it up with lots of extra info besides the tube types, like DC voltages at static conditions, and transformer part numbers for currently available units. I drew a schematic for my modification of a PA amp that may have too much information: http://members.aol.com/setzeramp/setz106.gif The amp before modification is posted also: http://members.aol.com/mbsetzer/davis106.gif If you are working with 6BQ5's you might find this interesting since they are used here in push-pull without a phase inverter, I called it self-inverting. My real question is about your drawing, it appears that you do not show coupling caps between the PI and the power section. I am wondering how close the drawing is to the working amp, if you are like me, the documentation is never accurate until after you have completely finished the amp for a while with no further changes, then almost unnecessarily take lots of time to go back and record the final configuration. Thanks for posting this, your pride in this project is obvious, and I think you will enjoy trying various preamps, for a start you can see if there is a booster or drive pedal that alone can bring your guitar up to decent levels for input to your amp. You could probably use the same type of box that would have enough gain to drive an amp while plugging the guitar through it straight into the FX return or power amp input of some amps.

5/17/2000 5:24 PM

MBSetzer

Re: pics

Hi Bryan:

Looks excellent to me.

I assume you are using 12AX7 and 6BQ5 tubes.

The schematic is nice too, but if someone was to try and duplicate your amp it would help if you cluttered it up with lots of extra info besides the tube types, like DC voltages at static conditions, and transformer part numbers for currently available units. I drew a schematic for my modification of a PA amp that may have too much information:

http://members.aol.com/setzeramp/setz106.gif

The amp before modification is posted also:

http://members.aol.com/mbsetzer/davis106.gif

If you are working with 6BQ5's you might find this interesting since they are used here in push-pull without a phase inverter, I called it self-inverting.

My real question is about your drawing, it appears that you do not show coupling caps between the PI and the power section.

I am wondering how close the drawing is to the working amp, if you are like me, the documentation is never accurate until after you have completely finished the amp for a while with no further changes, then almost unnecessarily take lots of time to go back and record the final configuration.

Thanks for posting this, your pride in this project is obvious, and I think you will enjoy trying various preamps, for a start you can see if there is a booster or drive pedal that alone can bring your guitar up to decent levels for input to your amp. You could probably use the same type of box that would have enough gain to drive an amp while plugging the guitar through it straight into the FX return or power amp input of some amps.

Replies:

Bryan James actually using 12au7 and EL84.<... -- 5/17/2000 6:28 PM
Bryan James My real question is about your d... -- 5/17/2000 6:32 PM