Hoof/Ungula

You could reduce the value of R22 to get some more gain out of the last stage
Will try to do that but it’s such a bitch to get it out of the enclosure and I hate accidentally pulling wires 🤣😂 What value resistor is ideal for R22? Thanks for the suggestion.
 
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DGWVI

Active member
Will try to do that but it’s such a bitch to get it out of the enclosure and I hate accidentally pulling wires 🤣😂 What value resistor is ideal for R22? Thanks for the suggestion.
Once you get it pulled, and the pads clear, try a few different values. I'd start with 1k, nd adjust as needed
 

Chuck D. Bones

Well-known member
Mine's pretty freakin' loud. This is the unity volume setting on my Ungula with fairly hot humbuckers. It's pretty damned bassy too.

HooF.jpgHoof - inside [sm].jpg
I did change my LEVEL pot to A100K. I respect Jamie Stillman's designs, but a 1M volume pot makes no sense to me. Whatever follows your Ungula may be loading it down. A lower value LEVEL pot might just fix that. You can up the gain in the last stage as DGWVI suggested, but you should adjust the bias if you change R22. Otherwise, you'll lose some headroom. Where did you get your 2N1308s? You might want to check the bias on those, in case they are too leaky. The 2N3108s are biased hot in this circuit, and if the leakage is too high, they'll saturate before the LEDs can conduct. On mine, the collector voltages for Q2 and Q3 are approx 2.7V. If they get under 2V, then there's a problem. If you want to try upping the gain on the last stage, you can use some clip leads and temporarily jumper a 2.2K resistor in parallel with R22. See if that gets you where you wanna go without pulling the board. Check the date code on those vintage 2N1308's: 134 = 34th week of 1971. Wish I had more o' those!
 
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Mine's pretty freakin' loud. This is the unity volume setting on my Ungula with fairly hot humbuckers. It's pretty damned bassy too.

View attachment 1612

I did change my LEVEL pot to A100K. I respect Jamie Stillman's designs, but a 1M volume pot makes no sense to me. Whatever follows your Ungula may be loading it down. A lower value LEVEL pot might just fix that. You can up the gain in the last stage as DGWVI suggested, but you should adjust the bias if you change R22. Otherwise, you'll lose some headroom. Where did you get your 2N1308s? You might want to check the bias on those, in case they are too leaky. The 2N3108s are biased hot in this circuit, and if the leakage is too high, they'll saturate before the LEDs can conduct. On mine, the collector voltages for Q2 and Q3 are approx 2.7V. If they get under 2V, then there's a problem. If you want to try upping the gain on the last stage, you can use some clip leads and temporarily jumper a 2.2K resistor in parallel with R22. See if that gets you where you wanna go without pulling the board.
I
Mine's pretty freakin' loud. This is the unity volume setting on my Ungula with fairly hot humbuckers. It's pretty damned bassy too.

View attachment 1612

I did change my LEVEL pot to A100K. I respect Jamie Stillman's designs, but a 1M volume pot makes no sense to me. Whatever follows your Ungula may be loading it down. A lower value LEVEL pot might just fix that. You can up the gain in the last stage as DGWVI suggested, but you should adjust the bias if you change R22. Otherwise, you'll lose some headroom. Where did you get your 2N1308s? You might want to check the bias on those, in case they are too leaky. The 2N3108s are biased hot in this circuit, and if the leakage is too high, they'll saturate before the LEDs can conduct. On mine, the collector voltages for Q2 and Q3 are approx 2.7V. If they get under 2V, then there's a problem. If you want to try upping the gain on the last stage, you can use some clip leads and temporarily jumper a 2.2K resistor in parallel with R22. See if that gets you where you wanna go without pulling the board.
nice build! I don’t know how to measure or bias things. I can follow instructions and diagrams. Got my tranny’s at usource.net they’re based in China. They get bad reviews but what do I know? All I know is the transistor(s) I bought worked for the pedal. I’m gonna try to do all suggestions likely tomorrow or Sunday. 🙏
 

Chuck D. Bones

Well-known member
My UTSource transistors came in a couple of days ago. At first blush I am disappointed and will not be placing any more orders with them.
My transistor tester tells me that out of the 20 Ge transistors I bought...
2 of the "2N1309s" are dead - completely non-functional
The "2N1308s" and "2N1309s" appear to be germanium, based on Vbe
7 appear to have E & C swapped
All of the functional so-called "2N1309s" are too leaky to use
All but one of the so-called "2N1308s" have HFE way below spec.
The "2N1308" and "2N1309" have the same K0424 LDC, very suspicious.
When I find my curve tracer, I'm going to verify the transistor tester results and probably seek remedy from Paypal.
 
Sorry to hear about that. I don’t know what leaky or any of all that means lol but yeah man if you’re not happy dispute it. I haven’t had issue getting my money back from them. So when transistors are no good and installed in the board how bad will they sound?
 

Chuck D. Bones

Well-known member
How an out of spec transistors sounds in a particular pedal really depends on the circuit. With Ge, I'll always pop them in the transistor tester first because they are so variable and different circuits require the Ge transistors to do different things. Si transistors I don't worry about because they're very consistent. Unless they come from a questionable supplier.
 

Chuck D. Bones

Well-known member
After some back & forth, UTsource refunded me the cost of the 18 bad transistors. I will not recommend them, there are too many good sources for Ge transistors. I have yet to find a good source for 1N34As. The ones I got from from Tayda and Guitar Pedal Parts are fugazi.
 

K Pedals

Well-known member
After some back & forth, UTsource refunded me the cost of the 18 bad transistors. I will not recommend them, there are too many good sources for Ge transistors. I have yet to find a good source for 1N34As. The ones I got from from Tayda and Guitar Pedal Parts are fugazi.
 
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