Pass Labs amps, pre, and Speakers

polkatese

Any thoughts on Pass Labs (experience, opinion, etc.)?

I heard it for the first time when I auditioned Cremona. It was tight, clean, and slam. I am impressed, I think it was the X5 series.

Where does it fall in terms of price bracket and performance with the rest of the competitions? thanks....

tryrrthg

Pass Labs is top notch gear. tough to beat, that's for sure. I've never had the pleasure to listen to them but I've ready nothing but good things about them.

When I listened to the Sonus Fabor Cremona Auditor, it was being run with Musical Fidelity A5 integrated and A5 CD player. They sounded VERY nice together.

At the Pass Labs price range I would also take a look at the McCormack DNA 500. It's being called one of the best solid state amps in the world. 500 watts per channel into 8 ohms, 900 into 4 ohms, will drive any speaker! If the DNA 500 is too steep in the price range, you could also consider the DNA 225. It is damn hard to beat McCormack gear in the bang for your buck department. I love my McCormack amp.

Steve McCormack runs an upgrade business so you could also have the amps upgraded by him. www.smcaudio.com

http://www.mccormackaudio.com/dna500.html

http://www.6moons.com/audioreviews/mccormack/dna500.html
quote from the the DNA 500 review above:

As for the McCormack DNA-500 itself, its particulars and pedigree? Read on. If, however, you're too busy to rummage through a lengthy, unabridged Chip Stern audio review at this time, stop here. As a public service, we'll attempt to telescope our cumulative emotional responses, musical impressions and base conclusions into one single sentence: "F*ck me - what a terrific amplifier!" [While I'm not sure this will ever make it into the top-10 list of most-used quotes, it is rather conclusively descriptive. And do we intuit an innate sense of mischief already in Chip's earliest surviving mug above? Must be that New York air. It liberates the tongue - Ed.]

http://www.stereophile.com/amplificationreviews/545/

polkatese

tryrrthg, thanks for the info!

tryrrthg

No problem, I LOVE your new speakers. They are gorgeous! Congrats!

polkatese

thanks, its soundstage is unbelievable...

heiney9

Pass Lab's is top notch stuff. Nelson is a great guy to boot. If you visit WWW.DIYAUDIO.COM they have a Pass Labs forum and he not only contributes to that forum but to others as well. Seriously if are really looking for insight/info about Pass Labs equipment visit there and you will gain more info than you can probably use. There are some very detailed analysis of Pass's approach to audio. I've only had 2 encounters with Pass designs. Both are with Nakamichi products and have been very favorable and positive. I breifly owned an PA-5 amp in about 1986 (similar to Threshold S-150). This amp used Nelson Pass's (when he was with Threshold) stasis output section. It was a very robust amp and once warmed up was very detailed and open. It was able to drive fairly complex loads and was a high current design, very balanced sound, excellent mid-range ability but lacked a bit of oomph on the bottom end (compared to the Adcom 555). When I worked in audio we used the PA-7 (the whole Nak 7 series) to drive the Polk SDA-SRS in our high end room. That was a great combo. Actually used to make the hair on the back of neck stand up with the right source material. The big design feature is Zero feedback. Very reliable and pretty indestructable. My current Nakamichi SR-3A receiver has the same Stasis design, albeit on a bit lesser scale than the PA-5. It has some of the same sonic characteristics as the PA-5 only I feel it's on a lesser scale becasue of all the other circuitry "interfering" since it's a rec. I'd put this rec up against anything today and I'm sure it would hold it's own and in many cases surpass many current products.

With Stasis, two amps drive each speaker. One is an extremely high quality low power "Stasis" amp designed to have exceedingly low output impedance. The other is a pair of "Current-Mirror Bootstraps" that provide very high current capability from a high impedance source. Becasue of the difference in impedance, the Stasis amp determines the output voltage, while the bootstraps provides the "muscle". Since the voltage determines the current flow, the Stasis amp controls the bootstraps and provides just enough current to make up for nonlinearities. This requires negligible power so the Stasis amp operates in a virtual equilibrium or "stasis" condition. Thus it is almost totally free of distortion without relying on global (negative) feedback. The tremendous peak current capability of the bootstrap amplifiers enables a Stasis amp to play louder and cleaner than it's ratings imply. The amps are also very heavy biased to class A operation and thus have a very high idle current so they tend to run hot.

Current Pass Lab designs have gone away from Stasis in it's purest form and Nelson is currently using Super-Symmetric Cascode circuit designs.

Check out some of the Threshold stuff as well. When I upgrade Threshold/Pass Labs amps will certainly be on my short list.

H9

unc2701

Nelson Pass is a true genius and everything he builds is top-notch... just be certain you know what you're buying- some of his stuff is very nitch. The first watt F1, for example only works with single driver speakers. The Aleph 5 is 60 watts pure class A, you can make toast on its heatsinks and it never pulls less than 300 watts, even if your pre is turned off. So do some research on the product before you buy it (and kick over to www.passdiy.com to see some really cool stuff).

heiney9

unc2701 wrote:

Nelson Pass is a true genius and everything he builds is top-notch... just be certain you know what you're buying- some of his stuff is very nitch. The first watt F1, for example only works with single driver speakers. The Aleph 5 is 60 watts pure class A, you can make toast on its heatsinks and it never pulls less than 300 watts, even if your pre is turned off. So do some research on the product before you buy it (and kick over to www.passdiy.com to see some really cool stuff).

Absolutely true....one of the nice things about Threshold/Pass Labs is there is tons of info out there...plus Nelson himself is so approachable, on the 'net anyways. But you do have to do you research and make sure you know how you want to use the products. I had forgotten about www.passdiy.com ...also some excellent info.....in fact start there as Nelson has written several pieces that give detailed explanations about his approach. He is very down to earth and not stuck on himself or his designs...like some others you read about.

H9

tryrrthg

It sounds like Nelson Pass and Steve McCormack are cut from the same mold. Super nice guys who just love all things audio. Steve has promptly returned COUNTLESS of my emails. He encouraged me to call him so we could chat, but I never did it. He often chimes in at audiogon and audio asylum forums.

polkatese, I just noticed you're in SoCal. Steve McCormack's upgrade shop is in Vista, CA. I know it's in SoCal, so depending how far that is from you that might be a possibilty for you to check out his stuff and chat with him.

I've been to the pass diy site before. I love El Pipo!

heiney9

While www.passdiy.com is a great resource, in my earlier post when refering to his articles one should visit this site

http://www.passlabs.com/articles.htm

H9

heiney9

tryrrthg wrote:

It sounds like Nelson Pass and Steve McCormack are cut from the same mold. Super nice guys who just love all things audio. Steve has promptly returned COUNTLESS of my emails. He encouraged me to call him so we could chat, but I never did it. He often chimes in at audiogon and audio asylum forums.

polkatese, I just noticed you're in SoCal. Steve McCormack's upgrade shop is in Vista, CA. I know it's in SoCal, so depending how far that is from you that might be a possibilty for you to check out his stuff and chat with him.

I've been to the pass diy site before. I love El Pipo!

That's the new Polk Power Port + for the new LSI subwoofer

polkatese

very good information, guys! thanks. I was blown off by the amount of energy Pass Labs Amps can put out. Well, the setup that I was in was also impressive, obviously the dealer has every reasons to make the experience in that audition room very memorable for the prospects. But, you both confirmed that Pass Labs products are top notch.

Thanks for the plug on McCormack too. That's what I am afraid of, a quick conversation that will lead to Bens running away from my wallet

amulford

polkatese wrote:

That's what I am afraid of, a quick conversation that will lead to Bens running away from my wallet

That's a given, you know that

gregure

Interesting thread. I don't have any personal experience with Pass Labs producst, but have only heard good things. I know that the fellas at Sumiko use Pass Labs to run most of their speakers during trainings and demos. These include the Sonus Faber Cremona, Amati, Stradivari and the Vienna Mahlers. They are also currently testing out a new 200 watts x 2 from Primare, an amp they are also very taken with.

W WALDECKER

gregure wrote:

Interesting thread. I don't have any personal experience with Pass Labs producst, but have only heard good things. I know that the fellas at Sumiko use Pass Labs to run most of their speakers during trainings and demos. These include the Sonus Faber Cremona, Amati, Stradivari and the Vienna Mahlers. They are also currently testing out a new 200 watts x 2 from Primare, an amp they are also very taken with.

i belong to the diy audio forums website. .i did a post on solid state amplifiers and low and behold who answered my post? it was none other than Nelson Pass. this man is a living legend and audio Genius. he is also one of the few top audio engineers that post schematics of his audio circuits for people to build if they are talented enough. as a matter of fact there is a entire forum segment devoted to Pass labs designs. pass labs amplifiers leave Krell in the dust.Top Shelf!

heiney9

W WALDECKER wrote:

i belong to the diy audio forums website. .i did a post on solid state amplifiers and low and behold who answered my post? it was none other than Nelson Pass. this man is a living legend and audio Genius. he is also one of the few top audio engineers that post schematics of his audio circuits for people to build if they are talented enough. as a matter of fact there is a entire forum segment devoted to Pass labs designs. pass labs amplifiers leave Krell in the dust.Top Shelf!

It just reiterates what I said earlier in this thread. I have had some correspondence with him as well. And he goes above and beyond for the hard core DIYer's. Always willing to diagnose problems and always willing to help them build Threshold/Pass Labs clones. He is a stand up guy and really is the Einstein of audio and truely has a passion for audio and is willing to share that passion.

H9