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Choice of Pass Labs Aleph for old MBL 101

I am looking for a good match for older MBL 101 (1990 production, no bass section / subwoofer, only three Radialstrahler units).
My current setup is:
Proceed PMDT - coaxial - Pass Labs D1 - rca - Pass Aleph 4 - 7 feet of 14 gauge copper - MBL 101.
(no fancy cables, I intend to move on to AES/EBU digital, XLR interconnects and some 8 feet of 10 gauge copper)
I skipped the preamp for now, as I listen only to digital, and Pass D1 has sufficient voltage swing to drive Aleph 4.
To characterise the current system's sound, once Aleph 4 has fully warmed up (a full hour), I am quite impressed.

The other day I noticed in our local, unassuming Hi-Fi store window a set of Pass Labs amps - a pair of Aleph 0 and an Aleph P. Asking price seemed fair (3000 Euros; as the store was closed, I know neither which version of Aleph P that is, nor if and when Aleph 0 s have their caps changed).

MBLs are =<4Ohm design (http://wegavision.pytalhost.com/MB/mbl92/, page 15: http://wegavision.pytalhost.com/MB/mbl92/MBL92_15_101.jpg).
Aleph 4 gives 100 W in 8 Ohm, and is optimised for 8 Ohm.
Aleph 0 is a 75 W amp, Class A SE at low power; however, it is able to leave Class A and do push-pull 150 W in 4 Ohm, and around five times higher impulse current than Aleph 4.

Now I wonder if MBL 101 would be better served by Aleph 0, or will it be more or less the same as Aleph 4 (or even worse)?
inefficient
4 responses Add your response
inefficient OP
40 posts
 
I recently got a Mark Levinson 23.
Seems to work much better with the MBL 101.
Now I have a chance to get a recapped ML 333.
-- Could ML 333 be better than ML 23 in this application (and in general)?
Post removed 
inefficient OP
40 posts
 
These old MBLs are less capable than 101 mk2 - no woofer box, single binding posts, Radialstrahler responsible for base all the way down (which is not very deep, at least with Aleph 4). The rest of the range is quite amazing though, and I do not want to spoil mids for gain in base. In an ideal world I’d try two Aleph 4 - one per channel  ‘paralleled’ ;-)
BTW, Once I put in place XLR cables, am I right in understanding that balanced connection for Aleph 4 will mean less gain = more nfb = less output impedance? If so, will that take Aleph 4 a small step closer to powerhouse imitation? (up to 100w Aleph 4’s power delivery should be effortless and dynamically uncompressed, as it is biased at 250wpc idle)
jperry
2,450 posts
 
Neither of these is ideal for the MBL. You need a real powerhouse capable of delivering lots of power into very difficult loads.
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