User talk:Machrone

Regarding Super Champ
Thanks for the info. Is the super champ circuit available anywhere on web? I would like to see if it's modiable or not. 75.156.106.118 (talk) 11:01, 19 February 2008 (UTC)

About Super Champ
I see that there was some other people wondering where you get the information on Super Champ. Personally, I am interested too, so if possible, can you also point me to where the schematic is?

On a side note, if what you said is true, then it is a preamp in that it provides a constant gain. Of course, it is not "tube preamp" in the traditional chance, is it? George Leung (talk) 23:21, 26 February 2008 (UTC)

Super Champ Schematic
I have an unauthorized copy of the schematic. I've been in touch with a Fender executive and he says it's their policy to publish the schematics for new products and that they will post the schematic for the SCXD "ASAP."

There isn't a heck of a lot you can do with the SCXD circuit, since virtually all of the tone shaping is in the DSP.

George, regarding the "preamp" function of the first triode stage, I'd have to say that it is not a preamplifier because the preamp should be the first thing that the incoming guitar signal sees, boosting it up and doing some emphasis/de-emphasis to shape the tone. In the SCXD, the signal goes through two stages of a TL072. The TL072 has some bandpass filtering to keep things in the audible range and prevent oscillation, then it buffers the signal before feeding it to the DSP.

The DSP has differential/balanced output and another half of a TL072 integrates the outputs to single-ended and applies audio bandpass filtering. The signal is buffered one more time by half of a 4560 before being fed to the first 12AX7 triode stage. It provides voltage gain and buffers the tube and solid state sections. There is no tone shaping, just standard values for plate resistor and cathode resistor/bypass cap.

The rumor that the SCXD is essentially a tube amp on channel 1 is completely wrong. The DSP is never bypassed and the Blackface voice of channel 1 is created by the DSP, as are the tone controls and effects applied to that chennel.