Aksa Lender P-MOS Hybrid Aleph (ALPHA) Amplifier

Founder of XSA-Labs
Joined 2012
Paid Member
GB Status Update:

Pinocchio - 1 pair, Paid
6L6 - 1 pair, Paid
bk856er - 1 pair, Paid
Vunce - 2 pairs, Paid
Pcgab - 1 pair, Paid
*jwjarch - 1 pair, Invoice sent
vvs07 - 2 pairs, Paid
jacques antoine - 1 pair, Paid
*GnuB - 1 pair, Invoice sent
Kokanee - 2 pairs, Paid
zman01 - 1 pair, Paid
Bvtrinh - 1 pair, Paid
MshipmanPE - 1 pair, Paid
muthumuthiah - 1 pair, Paid
Schlomoff, 1 pair, paid
markus22ch - 1 pair, need PayPal address
manniraj - 2 pair, Paid
Juntuin - 1 pair, Paid
Aatto - 1 pair, Paid
Wayne1 - 1 pair, Invoice sent

24 sets or 48 pcbs so far.
 
Few questions

Hi X

I have couple of question to you
Please let me know if the 2 Vout is connected together?
Second question Va with the green mark were is connected?
I started to do my layout, to that I must know that answer to that two questions. I know you wrote you U will have a professional layout for the 3 pairs so for that reason I only draw these layout for myself unless you want me to post the final work. :)
I do not worried about heatsinks
I built amps like Aleph X 22V rail voltage 7A total bias per channel. So no worries about the heatsink. :D
Thanks
 

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Founder of XSA-Labs
Joined 2012
Paid Member
Hi X

I have couple of question to you
Please let me know if the 2 Vout is connected together?
Second question Va with the green mark were is connected?
I started to do my layout, to that I must know that answer to that two questions. I know you wrote you U will have a professional layout for the 3 pairs so for that reason I only draw these layout for myself unless you want me to post the final work. :)
I do not worried about heatsinks
I built amps like Aleph X 22V rail voltage 7A total bias per channel. So no worries about the heatsink. :D
Thanks

Va is connected to the Va node after the CCS source resistors (on the other side of of R28. Vout is connected to the output before the load.

Make sure you are you using schematic from Post 155 (latest):
660208d1517584966-aksa-lender-mos-hybrid-aleph-alpha-amplifier-fciehdohbfnkegdm-png


Also know that the Big Boy version is yet untested. So you may be the test builder if you move fast. I have not had a chance to build it yet.
 
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Founder of XSA-Labs
Joined 2012
Paid Member
2 cylinders (LGA1366 cooler, ARCTIC Freezer 7 Pro Rev.2; board can accept many different CPU-cooler).

I´m braining about 3 Mosfets solution.

JP

That's a nice readily available cooler at a good price. Thanks, JP.

Do you know if it uses standard 12vdc fan or requires a PWM driver? Perhaps we can get a temp sensor tied to a safety shutoff relay logic signal to prevent fan failure blowouts?

How to clamp such a CPU cooler to PCB since it doesn't have a big plate? We could have a plate made out of a PCB material by the fab house too.

Amazon.com: ARCTIC Freezer 7 Pro Rev 2 - 150 Watt Multicompatible Low Noise CPU Cooler for AMD and Intel Sockets: Computers & Accessories

Edit: I see it is a PWM fan so requires a controller...
 
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Thanks for putting this together Pcgab. Those input caps look like a very reasonably priced but very high end performance. I might try them. Never thought of using a kV rated PP bypass cap before. Does that give it better attack on transients?

The Mills resistors at the big 3W locations look good as well. I found that cheap resistors here can make a difference with distortion.

Thanks again.
X

Happy to help!

I've used the 940 series 1kv and 3kv rated poly film caps on several combinations. They always seem to add a bit of clarity to less expensive caps.

I got the idea initially from(cmd-f for 'Cornell Dubilier 940C' on the page):

Humble Homemade Hifi - Cap Test


The difference is subtle, but I've been able to hear it on several attempts to prove myself wrong. Obviously it could all be in my head, but they're only ~$2 each if you buy 10 or more, so it's worth a shot to me.
 
Member
Joined 2010
Paid Member
Cooler's

That's a nice readily available cooler at a good price. Thanks, JP.

Do you know if it uses standard 12vdc fan or requires a PWM driver? Perhaps we can get a temp sensor tied to a safety shutoff relay logic signal to prevent fan failure blowouts?

How to clamp such a CPU cooler to PCB since it doesn't have a big plate? We could have a plate made out of a PCB material by the fab house too.

Amazon.com: ARCTIC Freezer 7 Pro Rev 2 - 150 Watt Multicompatible Low Noise CPU Cooler for AMD and Intel Sockets: Computers & Accessories

Edit: I see it is a PWM fan so requires a controller...

I noticed there were quite a few coolers listed below the Freezer 7 model, for not much more $$. There was a Artic Freezer 13 which came in 3 models that looked interesting.

I might have missed a point, "Are these coolers for the BB", or are you using on the 20W version also.

MM
 
Founder of XSA-Labs
Joined 2012
Paid Member
GB Status Update:

Pinocchio - 1 pair, Paid
6L6 - 1 pair, Paid
bk856er - 1 pair, Paid
Vunce - 2 pairs, Paid
Pcgab - 1 pair, Paid
jwjarch - 1 pair, Paid
vvs07 - 2 pairs, Paid
jacques antoine - 1 pair, Paid
GnuB - 1 pair, Paid
Kokanee - 2 pairs, Paid
zman01 - 1 pair, Paid
Bvtrinh - 1 pair, Paid
MshipmanPE - 1 pair, Paid
muthumuthiah - 1 pair, Paid
Schlomoff, 1 pair, paid
markus22ch - 1 pair, Paid
manniraj - 2 pair, Paid
Juntuin - 1 pair, Paid
Aatto - 1 pair, Paid
Wayne1 - 1 pair, Paid

Thanks to all of you for paying promptly! The boards have been ordered.

Let me know if I left anyone off or have the incorrect number of board sets.

I will be on travel this week and may not have access to email or internet so will not be able to handle new orders until I return in about 6 days.
 
Temporary hold
I have to stop with the Big Boy layout.
I see the 20W version circuit went through some (evolution) modification.
No reason for me to finish the layout until I do not see the final tested circuit, it is a lot of hard work to do a proper layout with the Paint.

I see lots of people ordered PC boards (I would love to get some extra power) for the 20W I hope someone can compare this amplifier to Pass Aleph #. I see some similarity between the two. I owned an Aleph 30 for a 6 months period, It was a great amp but I was not 100% satisfied (to me it was a bit bass shy) so I sold her. :) I only wrote I see some similarity, but sound wise definitely will be different than the Aleph 30. :)
The best would be to wait until someone build a BB prototype and test it in real life otherwise I will work a lot in wain.:D
 

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Hi Gaborbela,

Temporary hold
I have to stop with the Big Boy layout.
I see the 20W version circuit went through some (evolution) modification.
No reason for me to finish the layout until I do not see the final tested circuit, it is a lot of hard work to do a proper layout with the Paint.

This is good thinking. I agree. Let's wait until XRK has his holiday and then returns to finish the Big Boy.

JP64, again your layout is a masterpiece for the 20W. Thank you very much!

Hugh