Silicon Tone Bender MK II, are the resistors from emitters to ground optional?

[jpm83]

I see that GGG version has those resistors, but in this topic mac  says only to but 1Meg resistor between Q1's base and collector.
http://www.diystompboxes.com/smfforum/index.php?topic=62052.0
Janne

[jpm83]

Sorry I forgot the link. Now it's there.

Janne

[tcobretti]

The GGG pedal has been modded from the Ge original to work with Si transistors.  Mac is suggesting how he would convert the pedal to work with Si transistors.

Either should work.  The resistors on the emitters lower the gain of the transistors, much like Mac's suggestion of using super low gain Si transistors.

[mac]

I suggest the 1M from Q1 base to collector and the use of low gain Si to stay as close as possible to the original Ge version.

mac

[jpm83]

Thanks for the replies. I think I'm going to try that macs method since I have some really low gain silicon trannies (2N1893).

Janne

[mac]

Thanks for the replies. I think I'm going to try that macs method since I have some really low gain silicon trannies (2N1893).

2n1893: medium power transistors, 40<hfe<120. I'm going to ask at my local stores.

I quit using small pf caps from transistor B to C, or B to Gnd. I recently noticed a noise, kind of crackle, as notes fade away with the guitar volume lowered a bit. More noticeable when my amp is by my side, not right in front of me. I cut all the roll off caps in my Si FF and TB, and soldered 0.047uf and 0.1uf caps resp. across the 470 resistor. Like in the Axis Face.

mac