Pass Labs Aleph Question

I've owned Aleph 0's, Aleph 1.2's, Dunlavy 4's, Dunlavy 5's and Dunlavy 4a's. In my experience, if you want satisfying, well defined, articulate bass response out of the 4a's the Aleph 0's are your best all around bet. Of the Aleph series the original model, the 0, is the most well rounded of the bunch for most speakers. The Dunlavy's, while quite efficient, still needs the amp to take control of the woofers. If you're willing to do without the above described bass response, the later Alephs have a "sweeter", slightly warmer midrange than the Aleph 0. Be prepared for the heat these cubes throw off- the 1.2's being the largest are sufficient to effectively heat a small studio apt.

I owned Aleph 5s and their bass is excellent, but they don't have that iron-fisted slam thing going that some other solid state amps exhibit. As a point of reference, at orchestra concerts do you hear authoritative bass?

A great match I found for the 4a's was Classe. There seemed to be a definate synergy between those two lines. Try to find a Classe CA400. That was the best sounding of the CA series, has a boatload of power (400 watts), and runs cool.

I've owned the Aleph Os (the stereo version of the mono block) for years. It was driving my Thiel 2.2 for a while. When I upgraded to the Thiel 3.6, the Aleph Os was not powerful enough. But I kept it because it was just a very sweet sounding amp. It ended up in my second sytem powering a pair of Unity Audio Signature 1s. (Sonic Frontier SFT-1/ML #36DAC/ARC LS-1.) The system was very musical and the midrange was just awesome. Actually my wife prefer listening to this system over my main system.

I took down that second system and converted the room to the baby's room two years ago, and the amp has been sitting inside its crate in the garage. I started putting everything else for sale, but just could not bring myself to sell the amp. The only thing that would get me to sell this amp would be to buy a pair of the Aleph O monoblocks.

Recently I've decided to look for a new pair of speakers to replace the Thiel 3.6, and also to get a Pass X350.5. It just dawn on me the other day that I can use both the Aleph Os and the X350.5 to biamp. I think this would be a killer combo. We'll see. I have narrowed down my speaker choices to three, but have not made a final decision yet.

FrankC

I am using an Aleph 30 to drive the woofers in Zu Definition Pros. For 40Hz up I use a Red Wine Audio Clari-T with only 6 watts of output. I have found that you can alter the ratio of investment between amplification and speakers if the latter are very efficient. I'm driving $10K worth of speaker bi-amped with an $1100 amplifier investment and no compromise whatsoever. This provides better results than you will ever get driving $5K worth of speakers with $5K worth of amps.