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Which Pass Amp ?

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When considering doing a multi-channel BIII build, the question of which Pass power amp would work best with it in multiple output pairs needs consideration.
I've acquired almost all the pieces, BIII , the other TP modules, all various power supply, etc for a multi- or dual-mono. BUT...I intend to follow Russ's advice and "keep it simple at first with a stereo version"... to learn the DAC well before jumping into 4 or 6-channel (w/2 or 3 BIIIs) or dual-mono (w/2 BIII's).
I 'HAVE TO' at least swim in the multi-channel waters..... but can foresee Dual-Mono as a actually better trade-off.
OK, what have I not considered before I begin THE BUILD ?

Maybe, .... What the hell do I intend to feed all this to ? The Output power stages need to be flexible/expandable with common building blocks with each 2X channel increase.

Once I thought... Pass F5, even F5Tc. No! What a pain-in-*** 6ch bias beast that would be.
F4 - Ahh, its a DAC build, not a gain stage. And no, I'm not interested in using chip amps or class D !

With its stability, high input impedance (240K)...... even a sensitive 'glass' pre- would enjoy it.
A regular Joe, yet Class A ?
The Pass Aleph J seems to be a great choice ( but I could be wrong). Would not have to think of building a 4 or 6 channel J-amp. Believe I could simply add separate 2-channel stereo units. Common grounding may be big issue and possibly necessitate 'balance mode'.
So, long story short:
What do you think of Aleph-J power, feed by a Buffalo III DAC 2-6 channel ????

Charles
 
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Thanks Russ,
Just can't seem to focus on one component without considering the whole package. I like the J with its moderate output. With possible 6-ch, anything over 50W x 6 seems excessive.
If/When 6ch becomes my goal its apparent that 3 BIII's would be the best route. I'll take em one at time though
Charles
 
Official Court Jester
Joined 2003
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you can use upscaled* power amp (Aleph J ) for bass and downscaled** for mid and tweet

*both PSU voltage and Iq , comparing to regular FW iteration

** just Iq , comparing to regular FW iteration

if you end up having any particular question about Aleph J , ask in PL subforum
 
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in making the choice between 2 mono DAC channels or multi-channel, I think the crossovers deserve attention. I'm doing multi-channel because I never was 100% happy with my DIY passive crossovers. The best passive solution I found was at line level, but upgrading to a balanced signal chain pushed me to active crossovers, which are preferred.

Re the Aleph J, when I first heard the quality of the discrete Legato I/V, I was so impressed that I decided to build an Aleph J for mids & highs. The Aleph sounded great, but did not mix easily with my other amps so unfortunately it is idle.

ZM's suggestion for a modular approach makes sense, but how to nicely match the channels? Would it be possible to develop one fully differential front end that would drive a variety of different 10X power stages (maybe including Pass-inspired boards available from the DIY Audio store)? That way one could use discrete & class A components where they really shine, and other power circuits where class A is just too hot or unwieldy. ...a differential front end like a discrete version of the old TXD circuit? Perhaps making that work for kit-preferring end users is a lot to ask! :)

Cheers!
 
is amp the real Q?

I have B-II / Ivy-III balanced direct to PL XA100 monos for mids/tweets (passive xo), & unbalanced outputs from B-II through active xo to (non-PL) high-current amp for bass.
I tried active xo for mids/tweets as well, but prefer the sound of the passive xo.
Point is, the Q is not just which amps, but what xo & speaker-driving topology to use, & how to integrate sound through xo region if bi or tri-amping.
 
Have to agree somewhat with trying options for modular, bi/tri-amping XOs mentioned in 3 previous posts ...Thanks. Again, the options seems almost exponential.
My actual 'building' has been delayed by recent speakers I've accquired by dumb luck.
Picked up a nice pair of Boston Acoustics T1030 towers with biamping option. A week later inherited a almost new (unused/stored for 20+ years) pair of Boston Acoustics T1000......unbelievable ! Not SOArt, but perfect for modular XO setup.....
So fate is making decisions for me.....works for me, seeing how I can't make up my own mind.
I can see an amp atop each one of these towers maybe with PSUs in a bottom pedestal....
Each tower self contained feed by common source/DAC/Pre
Charles
 

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I'm driving F5 with Buffalo IIIse+Legato 3.1 directly and even with it's stock 1.5V i'm usually half turn of the volume with my 95db speakers. With less efficient stuff at friends systems i often have to go to 100% so mybe one day i'll mod legato outputs to 2V...

Sympatico is a great amp too. Using it in the summer, and class A for the winter :)
 
Yea, multichannel Class A is another concern: Although seasonal and locality dependant... But here in southern central Texas .... Probably should be more of concern to me than it is. 4 Aleph J's and McIntosh MC40 might be winter heat only.
But with more audio equipment than anyone should really have.....I've have decided to kept the multichannel a separate system from my conventional (WETHTI) stereo system.......mainly for simplicity sakes
 
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