Build This MoFo!

Two questions, gents

1. Would mofo work as a headphone amp with just a pot at the input? Provided the source had enough gain. I feel like i should add a b1 type buffer after the pot to drive the mosfet better?

2. How does mofo compare to ACA soundwise? I was actually underwelmed by aca, having been spoiled by f5 and vssa
 
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The MoFo-O....the last is 'O' is for overkill. Dual mono, 2x400VA@18, rails sit around 25VDC, biased at 2.5A. It really is an amplifier I can listen to all day, Thank you Mike!!
 

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Hey, this happen to any of you before? Involves the "break-in period", so here's your chance to close this thread. :D
This question is more about sound impressions of the MoFo, than about how to build it.

I'm not a great believer in break-in any longer. A few hours for electronics and a week or so for speakers when they are out-of-the-box new. That's it.
I think, the rest is the brain and ears adjusting. So, to me first impression are important, but not the final word exactly.

I had two new pieces inserted into my system: One was the 24v MoFo and the other BA3-Pre. They sounded excellent right out of the gate. Worst thing I could say is they sounded "chesty", congested in the mids. But, I was floored. Then, a day later things got a little ugly. Everything was 2D, flat, no dynamics and small sound stage. Did I make a mistake? Why did I spend 3 plus months and counting building the mono-blocks? Where did I go wrong?

I started thinking, well, maybe I made a mistake using a SMPS. Maybe the bias moved on both units. Maybe the caps I chose are not optimal for some reason. However, on the 3rd day- BLAMO! This system started to sing.
Incredible detail, bass that goes on for days (The MoFo is around ~20w? No way!).

Last improvement was the stereo image going beyond the speaker boxes. It's like the musical information was breaking free of the drivers and slowly floating around speaker and not come directly from the speakers like early on.

Then it occurred to me that I heard this sound before. Dare I say it? (Gulp!)
It sounds like the M2! It's that same command of the speaker cones and tonal saturation. The kind of sound that make you want to listen for hours and hours, and maybe even want to call out of work! ;)

Sorry for the drama, but I get emotional over this stuff sometimes. I'll regret writing this later, but for now, it's true. At least, it's the way I see it.
Give the MoFo a chance if you are on the fence. It deserves it.

The break-in part. Weird right?

Thanks for listening, :)

Vince
 
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