***Bazz Fuss Germanium Darlington***

[mac]

A mod to the Bazz Fuss using Ge transistors in a darlington pair config. Better sounding than the Si version IMHO. This Matsushitas 2sb176 (R) are amazing.



The Tone Bender 3-knob uses the same config., a 10k resistor from Q1 emiter to gnd. Adds a lot to the TB3 sound.
In this case, it let me use a higher collector resistor R1. Without R3, R1 was less than 1k. R3 dependes on the transistors leakage. The bad news is that temperature changes the bias point, so it must be adjusted very often.

A gain pot can be easily added, say 10K-A and a 2.2 - 4.7uF bypass cap. The value of R3 increases, near 80K in my tests. The gain pot works better than the guitar volume. Nice booster using the led and gain at min.

Original post:

http://www.diystompboxes.com/smfforum/index.php?topic=55004.0

mac

[JimRayden]

Time for a sound clip, I've been waiting forever.

Lovely design.

---------
Jimbo

[mac]

Time for a sound clip, I've been waiting forever.

That's what my girlfriends says

I owe some sound clips, not a big fan of them anyway.

mac

[mac]

Time for a sound clip, I've been waiting forever.
Lovely design.

Go to
http://guitarfxs.tripod.com/
for a sound sample.

My brother in law recorded it while I was away. Not sure if the circuit was biased correctly but it appears so.

mac

[8mileshigh]

Sounds worlds better than my Bazz Fuzz ! 

Chris

[brett]

Hi
the drive sounds excellent.  Very smooth.
But does it sound a little "gated" to you? 
I wonder how it would sound without SW2 and D3?  Why did you add those?
cheers

[mac]

Sounds worlds better than my Bazz Fuzz ! 

The stock version can sound a lot better by adjusting the collector resistor. R3 can be added to Si home-made darlington versions to fine tune the sound with a fixed 10k at the collector. In fact, many pedals like the jordan bosstone, the percolator, etc, sound better by adjusting some resistors.
In this Ge version, R3 does the trick by a) shunting some of the leakage to ground, or b) optimizing the best base current, not sure. I have to measure all voltages and currents to figure out what's going on when the sound is in focus.

Hi
the drive sounds excellent.  Very smooth.
But does it sound a little "gated" to you? 
I wonder how it would sound without SW2 and D3?  Why did you add those?
cheers

I called to my brother in law. He told me that he did not use D3, and that the mic was actually my AKG headphone!
I guess that distortion occurs because the collector can not move more than a diode drop from the first base, so why not adding another diode from the second base to the collector with an on/off switch. Just intuition.
It sounds a little gated and nasal, which is a nice combination IMO.

mac

[brett]

Hi

the mic was actually my AKG headphone

that's excellent.  Very DIY.

so why not adding another diode from the second base to the collector with an on/off switch. Just intuition.

I agree it's fun to try different things.  What effect does it have when you use that switch?

[mnordbye]

Sounds great! Wonder how it sounds with a bass guitar though. My bazz fuss sounds really cool with the stock version actually.

I've never been too interested in those germanium stuff though, seems hard to get a hold of. Where do you get yours?

Magnus N

[mac]

I agree it's fun to try different things.  What effect does it have when you use that switch?

Not a big difference, maybe more nasal sound. Should be omitted.

Sounds great! Wonder how it sounds with a bass guitar though. My bazz fuss sounds really cool with the stock version actually.
I've never been too interested in those germanium stuff though, seems hard to get a hold of. Where do you get yours?

Just replace the input and output caps with bigger ones. ¿4.7uf input cap in the original version?

Ge are a pain in the teeth but they sound a lot better than Si. I prefer to continually adjust voltages to compensate for temp changes than the harsh sound of a Si, even though my Si FF sounds very good!
I get my Ge from a small old elect store near home. Last time I bought a 100 bag of Matsushitas 2sb176 (r), original package, at about u$s 50,00. They seem to have been manufactured today! I got Toshibas and Sanyos as well from the same resource. And I have another cave in Buenos Aires. Bad news, no websites. Also I got some good Ge from tech schools and colleges in South America.
I'm going to ask if she has some more 100 units bags.

mac

[JimRayden]

Thanks for the clip. It's too sweet and overdrivey though. I was expecting for a more Woolly Mammoth-ish grind.

And if you could, omit those last bits of Si. Some Ge diodes ought to do it. The Si destroys all the mojo.

Sounds amazing but it's got too much sugar and honey in it to be called a bazz fuss.

---------
Jimbo

[Steben]

Sounds like a treble boosted Fuzz Face to me!  ... a good thing by the way

Is it the led or the si mode in the clip?

[birt]

the temperature drift in GE's can be solved by adding a GE diode somwhere near the first transistor i think. i have to open up my fuzz face again to take a peek tough..

[mac]

Steben,
Clip, D2 Si and no D3.

Jimbo,
Yes, 2 or 3 Ge diodes in series will do it. No traces of Si! I wonder how beatiful the beach would be if sand were Ge based!

birt,
It is a reversed diode from first base to gnd. I prefer a transistor of the same kind since it has the same temp properties. But in this case leakage and gain get amplified by the 2nd transistor, I have to test it.

mac

[juancra]

Hey mac!

I'm from Argentina also.I've bought a bunch of transistors and some 2SA101 are pretty low in gain ( in the range of 25).. Do you know if they're any useful?

[mac]

I'm from Argentina also.I've bought a bunch of transistors and some 2SA101 are pretty low in gain ( in the range of 25).. Do you know if they're any useful?

A very common ge here.
I have a lot of them, also 2sa102. These ge have a sub class, A, B, C, CX, etc., the higher the letter the higher the gain.
Datasheet available.
I used a 102 cx for my rangemaster because they are very bright.
Try them, you'll get a combined gain above 500 that is ok.
PM me.

mac