DIY Class A/B Amp The "Wolverine" build thread

Finished Amp... It is very quiet and sound great.
I used MJL1302AG/3281AG for the finals...
I installed larger heatsinks... 4.75 in x 14.56 in.
DC offset = 0.00
ripple on speaker outputs = 1mv
TP1 TP2 = 5.00v
After letting sit at idle (over an hour) with bias set to about 40 to 45mV, the heatsinks temps were about 80 deg F.
When I put the cover on the chassis, the bias voltage went down to about 30mV.
So if I understand correctly, with the cover on, I adjusted bias back to 44mV.
With it set like this and I remove the cover, the bias starts going up to about 55 to 60mV.
Is this OK?
Just a tip regarding the green pcbs on top of the transformers,
It might be worth replacing them with insulated terminal blocks which are mounted to the chassis
Just for safety reasons. Or join>solder>heatshrink them

Just don't want you to inadvertently get a shock

- Dan
 
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Are those F5 turbo's still in use or has the Wolverine become their favorite amp ? And what are those impressive speakers ?

kokkie:

The F5 Turbo V3 mono blocks are the principal amps in my main system. I also have a dual mono F6 and a VFET amp, both of which occasionally get thrown in for fun. I bought two complete sets of the Wolverine pcbs: the first set was installed in an integrated amplifier I built for my parents last year (which is the one you saw in the photo; see post #472: https://www.diyaudio.com/community/...rine-build-thread.385920/page-24#post-7114011). My plan is to let my parents' amp burn in for a couple of days; assuming it survives the burn-in, I'll (re)deliver it to them later on this week. I'll build the second set of Wolverine boards for myself at some point, hopefully soon.

The speakers are Elsinores, designed by Joe Rasmussen, which some friends and I built about 5 years ago (see my write-up at Post 2407 on the Elsinore thread: https://www.diyaudio.com/community/threads/the-elsinore-project-thread.97043/page-121#post-5690827). Like the Wolverine, the Elsinores punch far above their weight class.

There is no doubt that at times I depend on the kindness of strangers (yes, like Blanche DuBois). Doing so has enabled me to assemble several stereos (and a lot of stereo components) of a quality that is far beyond my means. This really is an extraordinary community and it's a privilege to be a very small part of it.

Regards,
Scott
 
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Here's a high-power sweep if anyone's interested. Again measurement setup laptop - E30 - wolverine - E1DA ADC

Q101, 102, 105, 106 - KSC D-grade straight from the BOM / KSA 'E' grade
Drivers - 4883A/1859A
Outputs - 2SC2292/2SC1216
Rails - 71V

Below is at 200W/40V into 8R. Again - nothing matched, not even close, except Q1/2/3/4, as per the build guide.

wolv dist 200w.jpg


Crazy. Onset of clipping measured at 43.8V.
 
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Just a tip regarding the green pcbs on top of the transformers,
It might be worth replacing them with insulated terminal blocks which are mounted to the chassis
Just for safety reasons. Or join>solder>heatshrink them

Just don't want you to inadvertently get a shock

- Dan
THX Dan... Those are the snubber circuits. I read that it's best to get them as close to the secondary windings as possible and the wire going to the boards are very stiff at this point. They do not move. It's only 40-0-40 ac and fused so it won't hurt to bad!!
 
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That whole thing is a house fire waiting to happen, do yourself and your family a favor and clean it up, including the non rated speaker wire you used. All chassis wiring should be voltage rated. The amp is just plain and simple not safe.
Ok, I will cover the snubber boards, I agree... I'm using 14g oxygen free copper speaker wire, what should I be using? And all the wiring used for the power supplies are from the toroid's excess wire. So I'm not sure what you mean about voltage rated.
I do know a little about high current/voltage power supplies as I maintain a lot of equipment at my job so please explain.
Some pics attached on some stuff I work on...
Scott
 

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So I'm not sure what you mean about voltage rated.
The insulator that covers the wire needs to be made out of an approved material to prevent or be highly resistant to fire.
One suggestion is good quality silicone wire. Its also way more flexible then toroidal transformer wire, which is usually quite stiff.

Please consider this for all your non rated wire. Amp wire

I've used it many times and its very good quality.

Please watch again the YouTube video on how to wire your amplifier there are may tips there. Wiring your amplifier.

That wiring that you have on the Perf board is not suitable for high voltage the outer rings of the pads are two close together to be save. You could get the voltage jumping across those pads. Maybe not now but in future as dust and other contaminants build up. Also those pcbs are certainly not design for the currents that are flowing through them.

We all want each other to be safe and what you have isn't, please don't take this as criticism think of it as an opportunity to improve and develop a better method to wire your amplifier.
 
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Should I remove the snubbers all together
If you're talking about the components used in the quasimodo
Rs, Cs & Cp they can get solder directly to your bridge rectifier or to whatever rectifier pcb your using.

From memory I believe @danieljw may have shown this in his video.

Or you can make up a basic pcb that the components solder to and mounts the rectifier.

I'll attach an example of the one I did.
 

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Yes the jacket of the cable should have a voltage rating, generally Zip cord speaker wire does not, and should not be used inside a chassis. Cable I use is all 600V rated.
Thank you, All these years I had no idea that zip cord speaker wire should never be used inside a chassis. I will change all the Amps I've built. Again, I'm very glad you pointed this out. Thanks much.
Scott