Pictures of your diy Pass amplifier

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Joined 2010
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Thanks for the kind words.

Are you going to try swapping out a different amp PCB, like the F4 or Aleph J?

No plans as of yet, although the Aleph J is mighty tempting. The nice thing with the universal chassis with all the DIY-friendly features is that the options for the future are wide open. For now, I am very, very happy with the F5-based design.

Thanks guys - always something new to learn and apply in future builds. ;)

That's the best part of this hobby; always something new to learn and apply. :)

What resistor value did you use for degeneration of the J74?
Are you using the 100 Ohm feedback resistors or the 220 Ohm? More or less gain?

I added 5R to the source of the J74. So, a total of 15R on the J74 source and 10R on the K170. The K170 set is matched to 6.5mA and the J74 set matched at 7.3mA

I am using 100R feedback resistors. I did not bump the gain.
 
Since the liquid cooled build is disassembled for chassis work, I thought I would share some pics that show the modular nature of the design. Remaining project elements are reservoir/pump rework, relief plug at top of water block, bottom drain, internal fan/motor speed controls and a high temp AC shutoff safety switch. Hopefully that will "Get er Done" :D
 

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Our last email exchange was just over a year ago so really a nice, well-planned one.

That and a whole lot of UN-planned life events... ;)

Gotta say, it is quite the little space heater at the bias levels I am using. Gonna be great for a typical mild Florida winter. I might never have to use my heat pump again! Hard to believe it might actually be considered somewhat "green" in the proper context.

Thanks again Blues.
 
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Finished my ACA.
They sound very nice for such small 5 Watt amplifiers. I use them at night when the kids are sleeping, to listen at low volumes.
At daytime the F5Tv3 is the one I listen to...:D

ACA has some difficulties controlling the big 4 ohm 10" woofers of my three-way speakers:)

Walter
 

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I had my F5 running for about a week in the diyAudio chassis. There's no way I could say anything negative about it besides its secondary function as a radiator. Yesterday, I finished up the Aleph J board swap, dialed it in, and buttoned it up. I've got to say the AJ is a perfect SS amp for an SE tube amp junkie. Here's the F5/Aleph J diyAudio chassis trip:
 

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Finished my ACA.
They sound very nice for such small 5 Watt amplifiers. I use them at night when the kids are sleeping, to listen at low volumes.
At daytime the F5Tv3 is the one I listen to...:D

ACA has some difficulties controlling the big 4 ohm 10" woofers of my three-way speakers:)

Walter

Its very very awesome design, i really appreciate to see it, thank you very much WalterW to inspire me, i really intend to do something like that.
I really wanted to meet you and see your amp and litle bit chat about it if possible.
Thank you again !