Tonebender / Fuzz Face Collector Resistors

[Jim Jones]

Hey guys,

Starting mucking around with some germanium trannies again lately and decided to make another TB MKII.  I used a Q1 tranny with an hfe in the 50 range and a 70 or so for Q2 and approximately 100 for Q3.  After doing some voltage measurements I found Q3's collector was fairly high (only a volt and a bit less than the supply).  The ideal Q3 voltage seems to be approximately half the supply voltage and it does indeed sound better to my ears at that voltage.  In order for me to accomplish this with the transistors I've used, I require a Q3 collector resistor of 18K(!)

Is there any problem with having the resistor that high?  Can you get to a point when the collector resistor has gotten too large?  Just wondering...thanks!

Jim

[petemoore]

Ge's can have varying bias needs and sound from one transistor to the next.

 Try Runoff Grooves FF and TB articles.

[brett]

No worries, as far as I'm aware.  If you check your 1k pot, you might find that it's on the high side (e.g by 20% or more), which leads to needing a higher collector resistor.  Just part of the huge variation that keeps Ge fuzzfaces suited to DIY rather than mass production.