[goldwerger]

Dukei recommended this shop: https://diyaudioheaven.wordpress.com/headphones/headphone-attenuation-adapter/

I got a couple of those at his recommendations and they are a perfect solution for low sensitivity headphones. Those work well on the output end. I think @justin w. is recommending/contemplating an attenuation pre input

 

[lsantista]

It shouldn’t be too long now. Dukei told me that most of the parts and boards have already been mounted in the amp case. Just waiting to get some specs from a certain brand to incorporate something different into the amp (if possible).

The amp case is bulkier compared to CFA3 as we’re going for the 4U chassis. Exact dimensions: width 320mm, height 165mm, depth 410mm.

Here’s the picture of the back of the amp:

are all dual chassis CFA3, also dual PS/dual DC in? Never seen the back of those cfa3 with the golden reference PSU , and never though about it. Great pic!

 

[normie610]

are all dual chassis CFA3, also dual PS/dual DC in? Never seen the back of those cfa3 with the golden reference PSU , and never though about it. Great pic!

I believe not all are dual DC in.

 

[chesebert]

I believe not all are dual DC in.

Are you going for the supersized soda can caps connected using solid copper power bus? Might as well go balls to the wall

 

[1Audiophool]

Got the pre-order email this morning. I’m intrigued to say the least!
Sold all my SS amps after I got the Envy. This might just be the one to get back into for SS -> Susvara.
Hmmmm decisions decisions!

 

[rsbrsvp]

I got a couple of those at his recommendations and they are a perfect solution for low sensitivity headphones. Those work well on the output end. I think @justin w. is recommending/contemplating an attenuation pre input

Correct. This solution will lessen the output power of the CFA-3. I already have three gain options and my lowest gain option is plenty low enough for easy to drive headphones, only that I like the sound better in higher gain (fuller, puchier) - but am left with no volume movement. The solution is a passive preamp where I can attenuate the INPUT into the CFA-3 from my DAC while maintaining the higher gain on the CFA-3 for these headphones.

 

[normie610]

Are you going for the supersized soda can caps connected using solid copper power bus? Might as well go balls to the wall

Perhaps not solid copper power bus, but possibly soda can caps I haven't seen the end result yet though

 

[K3cT]

sure but you already have one inside the amp

There is another way, which I have thought of offering...a standalone box with Kevin's ZF Buffer which is used in the CFA3 -- no volume control no switches just input on the back output on the front. Skip the gain stage entirely and run it from your volume controlled DAC or pre-amp.

I will be very interested in this variant.

 

[chesebert]

I will be very interested in this variant.

Curious, what's your use case for a unity gain buffer stage?

 

[K3cT]

Curious, what's your use case for a unity gain buffer stage?

Seems perfect to be used with a tube preamp for those pesky, inefficient planars.

 

[chesebert]

Seems perfect to be used with a tube preamp for those pesky, inefficient planars.

never had tube preamps, what kind of gain do those typically provide?

 

[kevin gilmore]

some of the older tube preamps (conrad johnson etc) did have output voltage swings of 30v or more. but only into very high impedance loads.

 

[Ethereal Sound]

+1, sounds intriguing

 

[normie610]

Got these PSU internal pics a few days ago.

 

[rsbrsvp]

WOW......