Does anyone build Ge Fuzz Faces with resistors and not trims any more?

[Nitefly182]

Im thinking about building a few fuzz faces and Im wondering if I can get away with just installing proper bias resistors instead of using a trim pot. As I understand the trim just biases Q1 but it seems like the right value resistor would work well and I wouldn't have to worry about working a trim pot onto a turret board. Ideas?

[frequencycentral]

I just did a Ge FF with all vintage parts. Stock values all round, sounds great to my ears! Dallas Arbiter didn't use trimpots.

[Paul Perry (Frostwave)]

My advice is to build with a temporary pot, tweak it to where you want it, then take out the pot carefully without changing the setting, & measure the resistance of the pot. then replace the pot by a resistor.
I don't know why people don't do this more often, if there is any chance that a madman will get at the pot..

[Paul Perry (Frostwave)]

Dallas Arbiter didn't use trimpots.

neither did most manufacturers - and that is why there is such a variation between examples of the same boxes from this era!

[brett]

Hi
if you get into FFs a bit, you'll realise that the 33k on the collector of Q1 is far from critical in terms of value. Rc on Q2 is much more important (the value of the fuzz pot is important, too, but is often overlooked).

Paul is on the money.  I would just use a 33k on Q1 and a trimpot to find an approx value on Q2 (either by ear or by Vc = 4 to 5 volts), which is then replaced by a similar sized resistor.

Have a good day.

[Nitefly182]

Sounds like Ill be able to drop the values in that come from small bear with my matched sets. Thanks guys!

[DougH]

Does anyone build Ge Fuzz Faces with resistors and not trims any more?

Sure, why not? I always use fixed resistors.

[frank_p]

My advice is to build with a temporary pot, tweak it to where you want it, then take out the pot carefully without changing the setting, & measure the resistance of the pot. then replace the pot by a resistor.
I don't know why people don't do this more often, if there is any chance that a madman will get at the pot..

Use a trimpot, measure and buy your resistors AFTER unless you want a huge stock of those.  I built a double Rangemaster this week that is mearly finished and guessed the values of the biasing resistors around the "common" ones.   Well I bought THOUSANDS of metal film resistors (packs of 100s) and still had to buy new ones to be in an "acceptable biasing range".  Don't do the same error as me, even if you buy a matched set.  You will perhaps want to adjust your sound and your bias voltages after receiving your trannies...

But, a good selection of resistors is a good thing.  It depends on you "goals".