If you want to have walk through of a Wolverine build using some nice parts check out my YouTube channel linked in my forum signature@ItsAllInMyHead Actually I did have one issue with my mini...I got distracted and put a MOSFET in the wrong spot, had to de-solder and find a replacement. But yes all in all it was very easy for me. I build a wooden enclosure, wired up an a different led power button, as well as rca, speaker, and DC power plugs. I really love that little amp, I just raised the bias a bit and absolutely love how it sounds with my tube preamp. But I just want more power 🙂
Any advice on which version to build?
- Dan
Watching nowIf you want to have walk through of a Wolverine build using some nice parts check out my YouTube channel linked in my forum signature
- Dan

Just a heads-up for everyone. R108 did NOT need to be changed in value. The problem ended up being the IPS board.
An FYI for other builders. I did find an issue with one board. When adjusting bias when I got close to 44mV across TP101 and TP102, it would suddenly jump up to around 68mV, then down, then up, etc. I found it was caused by R109 being at the end of its adjustment range. R108 was specified as 560R in the BOM, I'll be changing that board to 470R and installing a new R109 pot. That will move the adjustment more towards the middle of R109. This was also the board that I had to turn so far to get any reading across TP101 and TP102.
Here is the problem and the fix. The IPS board was swapped with another one. Still testing the bad IPS board.Just a heads-up for everyone. R108 did NOT need to be changed in value. The problem ended up being the IPS board.
I swapped the input transistors and had it on the bench all day with a 100mVpp 1kHz square wave running all day. Looked nice and square on the scope. I'll test it with one output pair on the spare output board to make sure it is really working.
Question for the smarter people on the group. Can I test the IPS and output board together with a +-30V bench supply if I add the 9.1k resistor to the IPS board? I plan to just add one set of transistors to the output board to make sure these last two boards are working.
I would actually run the bench supply at +-32V to make up for the losses across the diode, resistor and cap multiplier on each rail.
Yes, that's fine. Just remember to remove the 9.1K resistor before returning to the full rail voltageCan I test the IPS and output board together with a +-30V bench supply if I add the 9.1k resistor to the IPS board?
The BOM has a chart on page 2. Has more to do with your transformer wattage
Transformer for 2 Ch at 4ohms* | Expected Continous Power Out | Rail Fuses F1 & F2 | |||||
Typical | VA | AC | DC | 8ohms | 4ohms | Min Per Rail | Max Per Rail |
500 | 35 | 49 | 100 | 170 | 4A | 10A | |
600 | 38 | 54 | 120 | 210 | 4A | 10A | |
700 | 40 | 57 | 150 | 250 | 5A | 10A | |
800 | 42 | 59 | 160 | 280 | 5A | 10A | |
900 | 45 | 64 | 180 | 320 | 5A | 10A | |
1000 | 50 | 71 | 200 | 360 | 6A | 10A | |
Oversized | 600 | 35 | 49 | 120 | 210 | 4A | 10A |
700 | 38 | 54 | 150 | 250 | 5A | 10A | |
800 | 40 | 57 | 160 | 280 | 5A | 10A | |
900 | 42 | 59 | 180 | 320 | 5A | 10A | |
1000 | 45 | 64 | 200 | 360 | 6A | 10A | |
1200 | 50 | 71 | 240 | 430 | 6A | 10A | |
* Halve the VA rating, if you use a separate transformer for each channel | |||||||
* All power ratings are at 0° phase with a non inductive load | |||||||
* If using a transformer with a VA rating higher than the "Oversized" section, you should drop the rail voltage by one step, as it will sag less. | |||||||
* A transformer with dual secondary windings is prefered. |
Hi Rick,
The columb "Rail Fuses F1 & F2" should read "secondary volts AC".
Peak current needs to be calculated from the fuse data peak before opening and your SOA of the output stage. Look at elevated temperatures for safe operating area since if you're going to blow the fuse, the output stage is probably hot.
The columb "Rail Fuses F1 & F2" should read "secondary volts AC".
Peak current needs to be calculated from the fuse data peak before opening and your SOA of the output stage. Look at elevated temperatures for safe operating area since if you're going to blow the fuse, the output stage is probably hot.
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Thanks.The BOM has a chart on page 2. Has more to do with your transformer wattage
Copied from the BOM. I'm not the author.Hi Rick,
The columb "Rail Fuses F1 & F2" should read "secondary volts AC".
Peak current needs to be calculated from the fuse data peak before opening and your SOA of the output stage. Look at elevated temperatures for safe operating area since if you're going to blow the fuse, the output stage is probably hot.
Need some help here,
I tested one board at 30v and it worked fine i
I could do all the adjustments.
Now the other one I saw that one Led (D3) was mounted backwards,so I shutdown and replaised it.
Now the Led lights up as it should.But at R111A (TP107) and R111B (TP108) I get 11v,,,and I can ajust it up some volt with the bias pot.
And after a while Q105 and Q196 gets quite hot..I can adjust CCS LTP pot.
Where do I start?
I tested one board at 30v and it worked fine i
I could do all the adjustments.
Now the other one I saw that one Led (D3) was mounted backwards,so I shutdown and replaised it.
Now the Led lights up as it should.But at R111A (TP107) and R111B (TP108) I get 11v,,,and I can ajust it up some volt with the bias pot.
And after a while Q105 and Q196 gets quite hot..I can adjust CCS LTP pot.
Where do I start?
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