Passlabs Aleph 1.2 with CJ Tube 17LS/16LS Preamp

That may not be the greatest of matches. (this is my meaningless opinion only!) Why ?

A) The aleph 2 amps never really seemed to have that much power. Unlike most ss amps, the alephs don't have linear power output respective to load. The aleph 2 put 100w into 8 ohms, but only 160w into 4. I know my 100w arc vt100 had significantly more powerful bass than the 100w alephs. The mccormack dna-1 DEMOLISHED them in the bass department too. Your B&W speakers have wonderful bass. They always seem to benefit from big amps.

B) I found that the aleph's sounded noticably better in balanced mode.

C) CJ gear is more of a warm/glow sound rather than high resolution. I found when I put a tube preamp (AI 3a w/NOS telefunken) in front of the aleph's, it seemed to take away their spooky clarity. Not a good match at all. I also found the vk-30Se/aleph 2 didn't sound quite as good as the aleph P/aleph 2. The 30SE did WONDERS for the vt100 though! I have not yet tried my new BAT vk-5i/NOS with my aleph 2's. I plan too in the near future - will report !

You're correct about the impedance issue; it's not a good match electrically. It also depends on how difficult your speakers are to drive; the B&Ws are pretty demanding in this department. With your proposed setup I would expect a lean bass presentation and possibly a rolled off high end as well. Good luck finding the right amp. I did just read a good review in the Absolute Sound of the Marsh A400 which is a bargain, i.e., $2000 for a 200 watt amp, and possibly a better match for the CJ pre.

While I agree that the cj/Pass Aleph combo is not the best way to go because of the impedance mismatch, I do want to point one thing out. Arupg is considering Aleph 1.2's not Aleph 2's. While they share the same topology, the Aleph 1.2 is a whole diffent animal than its little brother. The 1.2 is 200 watts into 8 0hms and about 300 into 4. Having spent time with both amps, this extra power seems to make a lot of difference.

I am currently using 1.2's on Wilson speakers and have all of the bass performance you could ever want. It is tight, deep and very controlled. I to have used the Alephs with BAT preamps (the VK-5i and the VK-50se) and found it to be a pretty synergistic combination (the 50se was the better match). Like John, the best results I got was with a Pass preamp (which is not surprising given the natural synergy of using components from the same manufactuer. The combination of a Pass X0 pre with the 1.2's is hard to beat.

The 1.2's will do an excellent job of driving the B & W's but I would not recommend using the cj preamp with them.

Aleph amps (I have an Aleph 4) have all the bass extension you could want. The bass is very deep and would easily surpass the extension provided by the McCormack DNA-1. What the Alephs do not have is the powerful,extremely dynamic, explosive mid-bass that passes for extension, but is not. With the right speaker, these amps will easily rattle the walls, floor and windows with deep bass. While the Alephs may be somewhat of an impedance mismatch with their 10,000 ohm input impedance, they work well with many other tube amps, such as CAT and even Audible Illusions Modulus 3. I have auditioned the Aleph P with the Aleph amps and felt that their were better choices than that preamp for my Aleph 4. I auditioned the Aleph 1.2's before buying the Aleph 4. Even though I have no complaints about the Aleph 4 in the bass, I recollect that the Aleph 1.2, which was twice the power, moved significantly more air in the bass. Since the Alephs are quite neutral and refined, even they give you quite a bit of subtle detail and soundstage etc., they may not have the greatest synergy with warm-sounding equipment like Conrad Johnson preamps. You might look at preamps which call a little bit of attention to themselves, like the Hovland. It is still quite neutral, and quite liquid through the midrange, but the highs are quite detailed and spotlit. However, be sure to check out the bass of the Hovland. I found it to be significantly rolled off.

I find the B&W sound to have plenty of mid-bass, not much bass below that mid-bass peak and a balance which favors the upper mids and highs. Generally, I have found this balance to be fatiguing in the long run as the emphasis of the upper mids and highs is quite evident and not natural. However, there are many who favor this sound. The Aleph 1.2 might have synergy with this speaker, since its character is the antithesis of this kind of sound. Any problem that I have had with the Aleph has had to do with it being so smooth that the upper mids and highs are sometimes too soft. This will not be a problem with the B&W, so these might complement each other quite well.

I have a pair of Aleph 2's that I use with Talon Audio Khorus's . At first I was using an audible illusions mod 3 a with this setup. I had loved the sound of the mod 3 with my previous amp (McCormack DNA .5)nad it sounded pretty good with this setup too. However when I switched to the Pass aleph P there was a night and day difference. The bass was more extended and tigher the midrange clearer and the highs smother. These observations have led me to conclude that perhaps triode tube preamps are not the best match for the alephs. I feel the Alephs work best with the Aleph preamp. For a tube preamp they might not be the best choice.