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

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Just a quick photo (beauty shot? 😁) of another channel running after I updated the cap multiplier section from the latest build guide.

- Daniel
 
Good photo. What really bothers me is the split heatsink. This creates a strong thermal imbalance.
Hi Ralf,

Thanks, I know what you are saying and felt the same way. But the Wolverine amp has NPN, PNP, NPN, PNP, interleaved on each heat sink, also the brackets thermally couple the heatsink a bit, as does the close-ish fit between the two. If it really bothers you, you can use a copper "heat spreader plate" or aluminium plate. But I can say in practice after using 5 or 6 of these cases as long as you spread the transistors evenly over the two heatsinks it is really not an issue.

Hope this helps.

- Daniel
 
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Hi Ralf,

Thanks, I know what you are saying and felt the same way. But the Wolverine amp has NPN, PNP, NPN, PNP, interleaved on each heat sink, also the brackets thermally couple the heatsink a bit, as does the close-ish fit between the two. If it really bothers you, you can use a copper "heat spreader plate" or aluminium plate. But I can say in practice after using 5 or 6 of these cases as long as you spread the transistors evenly over the two heatsinks it is really not an issue.

Hope this helps.

- Daniel
When I built the Honey Badger, under Stuart's suggestion, I put a copper bar between and above the two split heatsinks, on which I mounted the output devices. But Honey Badger has separate PNP and NPN transistors. As you stated above, Wolverine is different.

Gaetano.
 

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When I built the Honey Badger, under Stuart's suggestion, I put a copper bar between and above the two split heatsinks, on which I mounted the output devices. But Honey Badger has separate PNP and NPN transistors. As you stated above, Wolverine is different.

Gaetano.
The copper bar could be used and is a great idea but I have done quite alot of measurement on the Wolverine without any problems so far.

Personally in this case I don't think it is necessary.

- Daniel
 
Hi Ralf,

Thanks, I know what you are saying and felt the same way. But the Wolverine amp has NPN, PNP, NPN, PNP, interleaved on each heat sink, also the brackets thermally couple the heatsink a bit, as does the close-ish fit between the two. If it really bothers you, you can use a copper "heat spreader plate" or aluminium plate. But I can say in practice after using 5 or 6 of these cases as long as you spread the transistors evenly over the two heatsinks it is really not an issue.

Hope this helps.

- Daniel
Right. But is it so hard to make such wide heatsinks for Modushop? It is technically possible, there are many photos of amps that are 30 or 40 cm deep.
 
Hi Ralf,

Trust me, if these heatsinks were something easy to obtain we would have purchased them a long time ago since I know there is a huge request for them.

Main problem is it's a lot more expensive to buy a single 400mm heatsink than 2 separate 200mm and our supplier hardly produces them because of that.

I've had other members tell me about the thermal imbalance and the solution they've come up with is something similar to what Daniel suggested: they've had us mill some 10mm thick "heat spreader plates" which are mounted on the flat surface of the heatsinks and cover a good part of so they could mount their components on top of them.
 
Hi Ralf,

Trust me, if these heatsinks were something easy to obtain we would have purchased them a long time ago since I know there is a huge request for them.

Main problem is it's a lot more expensive to buy a single 400mm heatsink than 2 separate 200mm and our supplier hardly produces them because of that.

I've had other members tell me about the thermal imbalance and the solution they've come up with is something similar to what Daniel suggested: they've had us mill some 10mm thick "heat spreader plates" which are mounted on the flat surface of the heatsinks and cover a good part of so they could mount their components on top of them.
If you can share pictures of this I would be interested. As an off topic for certain class A amplifiers (i.e. Aleph 60) in a 4U/500 chassis (i.e. two 250mm heatsinks), it can be beneficial!

Best,
Anand.
 
If you can share pictures of this I would be interested. As an off topic for certain class A amplifiers (i.e. Aleph 60) in a 4U/500 chassis (i.e. two 250mm heatsinks), it can be beneficial!

Best,
Anand.

Of course, here it is. This is basically a raw, non-anodized panel for the MiniDissipante 3U which covers most of the surface of the MonoBlock heatsinks

I'll let our friend Max jump in as he purchased them recently and plans to mount them on the MonoBlock chassis so he can give you some better feedback about this šŸ™‚ @MEPER
 

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You don’t recall where the bias is set do you? (mA I assume).
Anand:

My recollection is that the output transistor bias across TP101 and TP102 would bounce around a bit until the amp warmed up and then would settle down to about 43 mV. DC offset also vacillated but I was able to dial it in so that after the amp had been running for a while, offset on both channels ended up below 0.6 mV.

It was fun chatting with you at Burning Amp. Good luck with your Wolverine!

Regards,
Scott
 
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This is basically a raw, non-anodized panel for the MiniDissipante 3U which covers most of the surface of the MonoBlock heatsinks
I will use two similar pieces of aluminum, 10 X 125 X 295 mm, in my Dissipante 300 4U housing, this for other reasons. It will enable me in the future to experiment with different amplifier designs, using the same housing, supply and auxiliary circuits. If it was offered as an option, drilled and tapped, I would not have to worry about destroying the heatsinks.
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I am highly confident that it will work as expected.

As a bonus everything to do with mentioned housings brings back happy memories about Bologna and its surroundings, amazing Florence, romantic Venice, stunning Pisa and the trill of test driving a Ferrari.

I will use two similar pieces of aluminum, 10 X 125 X 295 mm, in my Dissipante 300 4U housing, this for other reasons. It will enable me in the future to experiment with different amplifier designs, using the same housing, supply and auxiliary circuits. If it was offered as an option, drilled and tapped, I would not have to worry about destroying the heatsinks.
View attachment 1109717

Please go ahead if you like. But this is unnecessary. Guy's please remember if its not in the build guide then its not required. We as a group have tested this and know its not necessary.