New amp - Pass X-150 or Classe CA-201

[tcrossma]

I'm in the market for a new amp and am currently tossing around these two amps: Pass Labs X-150 (approx $1600 used) or a Classe CA-201 (approx $1500 used).

Anyone have any direct experience with either of these? Or any suggestions for comparable alternatives in the same range? Upper budget is $1600.

Thanks

[heiney9]

Both are great but I really like Nelson's entire career design philosophy of simple circuits. The simpler the better.

Go for the X150 you won;t be disappointed

The Belles you have is no slouch but I think the Pass would make a more noticeable difference over the Classe vs. the Belles

[TroyD]

Never heard the Pass Labs...however, I had a big Classe amp for a long time and absolutely LOVED it. Wish I still had it.

BDT

[F1nut]

Why a new amp? That Belles Ref.150A is reputed to be pretty good. Just looking at your list, I'd have to suggest replacing that Adcom pre.

[Early B.]

Why a new amp? That Belles Ref.150A is reputed to be pretty good. Just looking at your list, I'd have to suggest replacing that Adcom pre.

Agreed. You have a few other potential upgrade opportunities before considering the amp. The pre is a weak link. Try some tubes.

[tcrossma]

I've already sold the amp, was just itching to try something different. So a new amp comes first.

I run the pre in passive mode, and am pretty happy with it so far. But granted my experience with different pre's is limited. I had read that that particular Adcom pre was supposed to be a very good one, but I don't disagree that it could be a weak link.

Thanks for the info guys -- I'll get the amp replaced first and then give some thought to the pre. I just need to find one that has an HT bypass. I had planned to buy a new dedicated CD player as the next purchase after the amp. Had been thinking of something like a Jolida 100 to get some tubes into the system. So now I'm not sure if I should do the pre or CD player first :)

[Mike Reeter]

Not to derail here,but this will most likely be my next pre.

http://www.soundstage.com/revequip/belles_21a_followup.htm

Used around $1000-$1200...HT by-pass also.

[heiney9]

Why a new amp? That Belles Ref.150A is reputed to be pretty good. Just looking at your list, I'd have to suggest replacing that Adcom pre.


I was thinking the same about the Belles. However, that Adcom is a simply an outstanding pre. It's not the typical "mid-fi" Adcom stock. Now if you want to venture into those glowing sphere's (tubes) then I could see replacing it. There is nothing wrong with the outstanding Adcom pre.

But I too and curious about why the change?

H9

[heiney9]

When you're ready to sell the pre (a mistake) send me a PM. I respect both F1 and EB, but you guys are nuts........that pre is outstanding; look past the name. I'd be interested to know how many times you've actually heard that pre-amp in your favorite system.

If you don't like the pre then you probably won;t like the X-150 since the Adcom is based heavily on the Pass Aleph P. Nelson had carte blanche in designing the pre for Adcom and stated he based it heavily on the Aleph P.

The GFP-750 is a Nelson Pass design—essentially a variation on the Pass Labs Aleph P and Pass's DIY project, The Son of the Bride of Zen (footnote 2). The circuit couldn't be simpler. Says Pass, "It's a differential pair—the end. A single gain stage, balanced input, balanced output, no feedback....We took a pair of MOSFETs, and the inputs go to the gates of the MOSFETs. The MOSFET sources are tied together and biased with a current source, with the signal taken off the drains. [The circuit] can run unbalanced on either side, although the performance is best when it's run balanced."

Other than glue logic and the transistors used to drive the relays, the 12 active devices—four gain blocks, each with three devices—are HEXFETs from International Rectifier. The output stage is intended to function as a pure voltage source, making the GFP-750 relatively immune to cable differences or low amplifier impedances. As we've come to expect from Adcom, the preamp sports a honkin' big toroidal transformer, with multiple secondary windings for each channel. A large heatsink on the left-hand side carries the power supply regulator chips.

Both signal and control circuitry is carried on one large double-sided printed circuit board, though these are physically separated. The parts quality is superb throughout, and care has been taken to keep signal paths as short as possible. The input switching relays, for example, are all adjacent to the rear-panel sockets. Did somebody mention the proverbial brick outhouse?

I post this info not to convince the detractors but to reinforce the good choice the OP made. Again if you're ready for tubes then of course this needs to be replaced.


BTW, if you ever want to sell.............shoot me a PM as this is on my short list of 3 pre-amps I'm interested in.

H9

[tcrossma]

I hadn't planned on replacing the pre, as I've been happy with it. But since my experience with pre-amps is not very extensive, I didn't (and don't) know if the Adcom is a weak link or not. I've read all about it and I initially purchased it thinking I'd keep it around for a long time -- it sounds good to me and it does everything I need, and in passive mode it just seems to disappear.

The Belles I sold just because I wanted to try something new -- just couldn't shake the itch to move on.

I think after I decide on which amp to try that a new CD player will be my next purchase after that. But H9, if I do decide to sell the 750 I'll let you know.

Thanks for all the help and info guys.

[heiney9]

I hadn't planned on replacing the pre, as I've been happy with it. But since my experience with pre-amps is not very extensive, I didn't (and don't) know if the Adcom is a weak link or not. I've read all about it and I initially purchased it thinking I'd keep it around for a long time -- it sounds good to me and it does everything I need, and in passive mode it just seems to disappear.

The Belles I sold just because I wanted to try something new -- just couldn't shake the itch to move on.

I think after I decide on which amp to try that a new CD player will be my next purchase after that. But H9, if I do decide to sell the 750 I'll let you know.

Thanks for all the help and info guys.

I think that's the most logical choice. Get some tubes in the mix with a nice CDP like the Jolida or similar.

Again, both the Classe and Pass are reputed to be excellent. My personal choice would still be the Pass. If you can get some listening time on both that would be ideal, however that's almost impossible to do these days unless you purchase both and compare them at home.

Good luck and you're certainly on the right track.

H9

[Early B.]

I respect both F1 and EB, but you guys are nuts........that pre is outstanding; look past the name.

Hey tcrossma -- you can't possibly take any guy seriously who named himself after his own ass.:eek: :p

[tcrossma]

Hey tcrossma -- you can't possibly take any guy seriously who named himself after his own ass.:eek: :p

You do make a good point ;) I respect all of your opinions, but for now at least I'm going to take H9's advice and keep the pre in my rig and upgrade a few other things first. I think the GFP-750 is a pretty good, transparent pre.

Oh, and one other thing I forgot to mention in terms of moving away from the Belles -- I really wanted to try an amp that had balanced inputs, as I had read that the GFP-750 works best with in balanced configuration. Not sure it's going to make any difference or not, but we'll see. I just pulled the trigger on a Pass X-150, so I'll see in a week or so how it fares against the Belles.

[DarqueKnight]

I'm in the market for a new amp and am currently tossing around these two amps: Pass Labs X-150 (approx $1600 used) or a Classe CA-201 (approx $1500 used).

Since your preamp is a Pass based design, you may realize more system synergy with the Pass amp. Of course, the only way to know for sure is to buy both amps and compare in-house.

You may be able to find some owner reviews and other info for the Pass and Classe amps on the Audiogon and Audio Asylum forums. There may also be some info from owners of the X-150 on the Pass Labs forum at diyaudio.com


...that Adcom is a simply an outstanding pre. It's not the typical "mid-fi" Adcom stock.

The GFP-750 is a fantastic preamp. I once owned two of them which were used in two separate systems. Were it not for my "no hoarding" rule, I would still have them. I also would not hesitate to buy one again.

I upgraded the GFP-750 to the Pass Labs X1 and again to the Pass Labs X0.2.

Reference: Pass Labs X1 Preamp vs. Adcom GFP-750 Preamp (http://www.polkaudio.com/forums/showthread.php?t=44152)

[Early B.]

Oh, and one other thing I forgot to mention in terms of moving away from the Belles -- I really wanted to try an amp that had balanced inputs, as I had read that the GFP-750 works best with in balanced configuration. Not sure it's going to make any difference or not, but we'll see. I just pulled the trigger on a Pass X-150, so I'll see in a week or so how it fares against the Belles.

Cool. Nothing wrong with changing out amps to try something new. I'd love to hear your impressions of the Pass Labs amp. If for some reason I went back to a SS amp, I'd like to try either a Pass Labs or a Plinius.

[heiney9]

You do make a good point ;) I respect all of your opinions, but for now at least I'm going to take H9's advice and keep the pre in my rig and upgrade a few other things first. I think the GFP-750 is a pretty good, transparent pre.

Oh, and one other thing I forgot to mention in terms of moving away from the Belles -- I really wanted to try an amp that had balanced inputs, as I had read that the GFP-750 works best with in balanced configuration. Not sure it's going to make any difference or not, but we'll see. I just pulled the trigger on a Pass X-150, so I'll see in a week or so how it fares against the Belles.

Most excellent choice................I am currently awaiting delivery (hopefully in a few hours from UPS) for my Pass Aleph 30. A distant cousin of the X series. Took the day off to ensure face to face delivery.

The Aleph also has balanced inputs and is reported to run best using those too. My brother has a GFP-750 and I've been trying to coax him to sell it to me as he has another alternative for a pre..................so far no luck. :)

Enjoy and give us your impressions............

H9

P.s EB...............sticks and stones.....yada,,,yada,,,yada. :D:)

P.s.s The waiting is KILLING me!!!!!!

[DarqueKnight]

Took the day off to ensure face to face delivery.

Since you took the day off and are sitting by the door, this insures that the next time you track your package online you will see the following message:

Delivery Exception - Rescheduled for 2-4-2008

[heiney9]

Since you took the day off and are sitting by the door, this insures that the next time you track your package online you will see the following message:

Delivery Exception - Rescheduled for 2-4-2008

LOL-- that better not happen. It's coming from Ohio to Illinois and it already lost a full day due to the storms in that area last week. The UPS authorized shipping center never opened on Wednesday to ship it out (the seller dropped it off after pick-up on Tuesday evening). It's only 2 days to IL from OH so I was Pass-less all weekend :).

H9

[DarqueKnight]

Just keep in mind that delivery efficiency is equal to the reciprocal of the anticipation of the item squared.

If the item is something you actually need, then the delivery efficiency is equal to the reciprocal of the need of the item cubed.

Hope this helps.

[Face]

Just keep in mind that delivery efficiency is equal to the reciprocal of the anticipation of the item squared.

If the item is something you actually need, then the delivery efficiency is equal to the reciprocal of the need of the item cubed.

Hope this helps.

Ain't that the truth! I'm still waiting the arrival of capacitors and resistors that shipped from the Netherlands 3+ weeks ago. :mad:

[DarqueKnight]

I'm still waiting on a turntable motor that was ordered 1/5/09...from Colorado.:(

[DarqueKnight]

In non-audio merchandise, I am still waiting on some glass lamp shades that I ordered on 6/23/08. It seems that the shades are made in China and the factory was tied up for several months making stuff for the winter olympics. I am scheduled to get my shades in March (of this year).

[reeltrouble1]

In every life some rain must fall.

RT1

[lakesailor]

I am glad to hear you made the choice to go with the Pass X150. As a former Pass X150 owner my only regret was selling it to buy a Levinson instead.

I also had the GFP 750 pre-amp; though I was less impressed with it.