Power amp around $3000 for C-J Classic preamp

I would think very hard about the Quad 909. I think that with the classic would be a dream. Underwood hi fi sells those at a great discount, and it has gotten rave reviews. It will drive most anything at a conservatively rated 140 per side solid state. Reliable too. Good luck.

Retails for $1500 or so, but sold new at a discount at name above.

I'd suggest a used Spectron Musician III.

I would seriously consider a used cj mf2500a ....... Or McCormack DNA 250

You have a broad choice of speakers with different needs. The Totems need a high quality solid state amplifier with a lot of power to sound their best. I used a 100 watt Krell amp with decent results.
With either the Vandersteen 3A Sig or the VMPS you can use a tube amplifier, but for best results it will have to be fairly high powered.
I personally do not recommend the Quad amp since my personal experience is Quad does not work well with other brands.
As I always recommend, for best results Amplifier and Preamp should be the same brand. The is always a rightness to the sound.
Decide on the speaker first then the right amplifier to drive them properly.

I was recently chastised offline by a Vandy dealer for recommending 80 watt amps for the 3a's. So, whatever you get, make sure it is fairly potent and doubles down to 4 ohms at least.

Musical Fidelity 308 would be one, I have used several of their units. Parasound A21 [the 250 watt stereo] has a good rep. These are both way under your limit. There are just too many possibilities, especially since the speakers are uncertain. Unlike the previous poster I very rarely use the same make amp and pre amp, I think the last time was around 1990 except for integrated amps. When I do it is more by coincidence than planing; when you read reviews of an amp and preamp almost invariably one will be regarded as the star of the combination. The CJ should work with a wide variety of amps, decide on speakers first and then pick an amp that will drive them well. While it is true that manufactures make their units in combination you may or may not like the sound they were striving for. In my long ago days as a Krell dealer I liked their amps considerably better than their preamps; I have thought seriously about getting a Pass Labs pre, but don't want to deal with Class A amps again. I think if you look at members systems you will see many if not most have mixed marriages in their electronics.

Whatever amp you choose, be aware of the input impedance and the CJ preamp's output impedance. Choose wisely.

Not only are like brands of amplifiers and preamps designed to work well together sonically they are also designed to work well electrically and I have heard plenty of bad matches.
If you don't mind the process of buying and selling while you mix and match until you get it right or if you have several amps and preamps on hand to try together, your safest bet is to stay with the same brand.
I agree with Stanwal, CJ preamps are one of the easier to match with, say, a solid state amplifer, but you don't have a CJ yet and you may end up with something else.
The Quicksilver full function preamp works especially well with a variety of amplifiers because of it's extremely low output impedance.
But unless you have a ton of stereo equipment lying around as I do from my days as a stereo dealer and collecting choice items over the years as a hobbiest, then you may want to stick with the same brand.
Keep in mind many solid state preamps often take up to 3 days before sounding their best, such as Krell, Mark Levinson, Threshold and Audio Research solid state and hybrid preamps.

Foster_9, That is very good advice.

I have posted this before because it is a good example.

Several years ago when the Audio Research LS-2 was new, Stereophile reviewers were using it as their reference preamp. Don't ask me why. I never warmed up to the LS-2. During that time there were two new mid-priced solid state amplifiers on the market. One was the McCormack DNA-1 and the other was the Parasound HCA-2200.

The Stereophile reviewer reviewed these two amplifiers using the Audio Research LS-2 preamp and gave the DNA-1 a glowing review while he literally trashed the Parasound amp.

I had both the LS-2 and the Parasound amp on hand at the time and I found it hard to believe an amplifier could sound so bad.

I proceeded to connect the LS-2 to the HCA-2200 and I could not believe how bad it sounded. I had a feeling something was wrong with the match, so I took the LS-2 out of the system and I connected the Music Reference RM-5 MKII. The sound was instantly transformed and the system sounded wonderful.

This was more than just the sonic signatures of these two components not jiving together and the Parasound turned out to be a very nice and powerful sounding amp, but it was too late. The DNA-1 was a hot seller and the HCA-2200 was not because of a reviewer's negligence.

Stop! Decide on your speakers before proceeding any further.

Used CJ Premier 12 monos.

I agree with several postings above that you should decide on the speakers first. Vandersteens have a reputation for working well with McCormack and Audio Research amps. A used cj MF2500A would be another good match for the Vandies and certainly with the cj classic preamp. One more thought about the McCormack...you could buy one for under your current price limit and have it upgraded by SMc Audio. I am currently running an extensively modified DNA-1 Deluxe into 3A Sigs. with great results. The high current of the McC really coaxes the dynamics out of the Vandies.

Thank you all for your advice. I'm pretty much convinced I will go with the Vandersteen as my local dealer happens to carry both Conrad-Johnson and Vandersteen and they've been pretty good to me. Also, I might keep my Hawks around as well so I think a solid state with some extra muscle is the route I'm going to go.

A few extra questions:
1. I noticed the C-J mf 2500a is not a current C-J product. Is this an issue as far as availability? It seems I can find a used one easily, but the fact that is appears to be discontinued worries me a little. And why discontinue a fantastic match to a new preamp with a great matching price? I'm baffled.
2. Foster_9, I too wondered about the impedance matching and was wondering whether you or someone else could explain a little more what to look for. (I'm using an integrated amp so this has not been an issue for me and thus eludes me.)
3. Musical Fidelity recommendation. What I've heard from MF always blew me away so I'd be very happy to own their amp, but the recommended 308 appears to be an integrated amp and also no longer in production. Any current MF power amps that might fit the bill?

Thank you!

Hello,
Currently Spectron Audiois haviing promotion for its Musician III which should fit in your price range.

They do not have problem with impedance as their recent models have all 50 kOhms input impedance !

In recent post by Lube3 (Lube?) he compared McCormacks 750 with Spectrons and Spectrons 'smoked' this competition - do search, its here on A-goN discussion forum

I and many others owned in the past tube amps and Spectron is well among the best

All The Best in your Search!
Rafael

The conrad johnson can be paired perfectly with a LP66S power amp, it is the perfect match for bright sounding speakers.

If you are looking for powerful amp under $3K new to match with the cj Classic and big Vandys, I might suggest:

Cambridge Audio 840W - unique design inside, great result.

Vincent Audio SP-T100 Hybrid Mono amplifier - not full on solid state amp, but powerful and great anyway, and in your price range for a pair new.

Odyssey Audio Stratos Mono Extreme - My favorite Sleeper product - in this case the hybridization is German engineering and built in the USA - they are almost as good as our hockey team, but in this case, you win!

At a bit to well over the $3K price point you could check out:

Musical Fidelity M6PRX - latest 260W offering from the company that thinks power is almost everything.

Bryston 3B-SST2 - if you like that sort of thing, transparency may match well with cj warmth and Vandy presentation - although the 4B might better marshall the big Vandys around - Oh Canada!

McCormack DNA-250 - va va voom!

Conrad Johnson, I believe, has discontinued production of pure solid state amps such as the MF2500A and the Premier 350. They have acquired McCormack, and it seems to me that their pure solid state amps are now being produced under the McCormack label. Other than that I am not sure why they stopped production of these amps as they are excellent.

Also I would not be concerned about buying a non current cj amp as they have excellent customer support and will continue to support the non current product . And yes cj is using McCormack as their ss amp line-up.

Someone mention Premier 12 mono bloc's which is also an excellent choice as long as you don't mind the costs associated with replacing tubes; not to mention the heat associated with tube amps.

Pairing a cj pre with a cj amp makes very good sense and you won't have to worry about compatability issues.

Chuck

The McCormack and c-j amps differ enough that I would clearly choose the McCormack's over the c-j's for use with Vandersteens. If other speakers were to be considered, I could easily flip flop. I wouldn't even think about a pre till you've got the speaker/amp match worked out.

Actusreus, the input impedance of your power amp should be at least ten times the output impedance of your preamp. I've been told that without this the highs and bass will be rolled off. Actually if the input impedance of the amplifier is twenty, thirty, or more times the output impedance of the preamplifier that's even better! And typically, the lower the output impedance of a preamp the better for performance with an amplifier. But I'm no expert on technical parameters. I just learned about impedance mismatch when I got back into seperates after years of buying integrateds.

FWIW, Steve McCormack owns Vandersteen 3A Signature loudspeakers. They are what he uses in his reference system to voice his amplifiers (and his SMc Audio component modifications).

The Vandersteen/McCormack pairing is a no-brainer if you want to avoid guesswork.

you are offering i am sure well intended but misguided info.((Cambridge Audio 840W - unique design inside, great result.)) Nice amp but Lowish input imp so so match with a CJ tube pre amp

((Odyssey Audio Stratos Mono Extreme - My favorite Sleeper product - in this case the hybridization is German engineering and built in the USA))
Also nice amp
Also Lowish input imp so so match with a CJ tube pre amp

((Musical Fidelity M6PRX - latest 260W offering from the company that thinks power is almost everything.))
Lowish input imp so so match with a CJ tube pre amp
Please dont take this the wrong way but Perhaps you could stick to tried and tru endorsements instead of ......
Cheers Johnnyr

Unsound really offered the most sound advice. The OP seems to be headed toward a wholesale system change over the next year or so.

Decide on speakers first. Then the appropriate amp. Then the preamp.

Choosing a preamp first before speakers or amplifier is really going about it completely backward, and frankly it's a recipe for disaster.

Again, thank you all for your advice and input.
Tvad, you're correct that that's the direction I'm headed, but it seems to me I should still be able to match an amp to the Vandys and C-J preamp. I've wanted to own both the 3As and a C-J preamp for years (C-J even more so), for a variety of reasons. The Classic fits the bill perfectly and even if "unsound," I don't want to discard the idea of owning the Classic just because as a generally accepted rule, I should start with the end. We have the speakers, we have the preamp, now let's choose an amp! I realize the $3000 budged might put some limitation on the choice, but that should still get me something decent, shouldn't it?

CJ doesn't list the output impedance specification of the Classic preamp, so matching with an amplifier becomes more complicated. You should call CJ to get an answer to this important question.

You might be best off with a CJ amp to avoid the matching guesswork.

Whether the CJ amp is the best choice for the speakers you choose is another question.

Good luck.

Tvad, I did notice that as well, which I think is disingenuous on the part of C-J (or any other company that doesn't provide essential specifications for their equipment).
The C-J power amps tend to be very expensive, offer rather low wattage for the price and the top models are unfortunately beyond my reach. Seems the mf-2500a might be an exception, but is no longer in production.
As much as I'd like to own the Classic, I'd perhaps be willing to look elsewhere for a preamp, but I just don't see anything below $2000 that would seriously compete with the Classic. I'd love to own a ModWright preamp, for example, but they cost too much for my budget. If anyone has sugestions, I'd love to hear them. Thanks.

I'm not sure the c-j Classic would have been the best match for the Vandersteens anyway.

John,

Well intended, yes. Misguided? Probably. Your velvet hammer can actually lead to enlightenment for me and perhaps others in the long run if we know what the actual numbers are for the input impedance's for each of the solid state amps I suggested:

-Cambridge 840W = 38-68 kOhms

-Vincent SP-T100 = 48 kOhms

-Odyssey Stratos Mono Extreme = 22 kOhms

-Musical Fidelity M6PRX = 50 kOhms

-Bryston 3B-SST2 = 20-50 kOhms

-McCormack DNA-250 = ???100kOhms???

Balanced inputs are lower of the two impedance numbers where two appear.

So if what you say about the MF and Cambridge having "Lowish input imp" holds for the others, then all of these amps except perhaps the McCormack have input impedance's that are too low to match well with the cj Classic. I can't find a value for the relatively new McCormack DNA-250 anywhere, but the DNA-225 was 100 kOhms, so I assume, perhaps wrongly, that they are the same. (side note, Spearit Sound has a refurbished DNA-250 available for $3000 right now.)

To help with understanding these relationships in general, it would be very helpful to know what the output impedance value is for the cj preamp to know what you do not consider a good match for these fairly typical solid state amplifiers.

For comparison, the output impedance of the matching Musical Fidelity preamp is 47 Ohms. The output for the matching Cambridge preamp is 100 Ohms, while Odyssey preamps are listed as 70 Ohms (solid state) or "low" (tube). So all are fairly low.

In contrast, the PrimaLuna Prologue Three tube preamp is a whopping 3.5 kOhms, while their matching mono block tube amps have a fairly high input impedance of 100 kOhms. If the cj is considered such a tough match with many of the solid state amps listed above, then it must also have a fairly high output impedance - more similar to that of the PrimaLuna?

Enough said.

OK, well, one more thing. If you are considering dumping the cj Classic idea, then I would suggest pairing any of the amps listed above with their matching preamps. I.E. Cambridge 840E (solid state), Vincent SAT-1 (tube), Odyssey Candela (tube), or the Bryston BP-6 (solid state). These systems could all drive the Vandys and the preamps are nearly guaranteed to match well with the same name amplifier.

A completely different approach would be to pair the Primaluna ProLogue Three preamp with the ProLogue Seven mono blocks. All tube system, but self biasing and a lot of tube power on hand to drive the 3A's.

If you decided on Vandersteen 3As and you want good sound forget about CJ and go with Audio Research. There is always plenty of used Audio Research available and once you've heard Audio Research with Vandersteens you will have no regrets.

I called C-J and the Classic's output impedance is 200 Ohms. If, as general rule, the amp's input impedance should be at least 10 times the output impedance of the preamp, all of the amps mentioned in the thread should work just fine with the Classic. Even though the Classic has a higher impedance than most solid solid state preamps, any amp with impedance of more then 2k Ohms would comply with this rule. The lowest impedance of 22k Ohms for the Odyssey is still over 100 times higher than impedance of the Classic. How is that "lowish"?

Actusreus,

Good to know and a good point. While I have been told and/or read that the PrimaLuna pre is a bad match for amps like the Stratos, I cannot see that impedance mismatch alone could be huge problem for pairing the cj Classic with any of these high value solid state amps given an output impedance of 200 Ohms.

Audioconnection's point about sticking with tried and true combinations may more appropriately apply to speaker/amp interactions in this case. I tried to suggest the amps I like below or around three grand new that could drive the hungry 3A's. These should all sound "good". Whether they will sound as good in combination with the 3A's as many here suggest ARC gear will sound, I cannot say but doubt it. In many cases you get what you pay for. ARC pre's and amps are listed here all the time used, and sell faster than pretty much any other brand.

No matter what direction you go, good luck, the Vandys are nice speakers.

03-04-10: Actusreus
I called C-J and the Classic's output impedance is 200 Ohms. If, as general rule, the amp's input impedance should be at least 10 times the output impedance of the preamp...

IMO, that 10x rule of thumb is an oft repeated fallacy. What is more appropriate, is 10x the measured *high* output impedance of the preamp.

Output impedance will always vary along the frequency range. While the CJ may have a nominal output impedance of 200 ohms, it's not unreasonable to expect a high output impedance from a tube preamp of something along the lines of 2000 ohms. For examples, read a few of John Atkinson's test measurements sections of Stereophile tube preamp reviews. You'll see how output impedance varies considerably from the manufacturer's nominal specification.

The bottom line is that the higher the input impedance of an amp, the better will be the success of matching a tube preamp.

BTW, the Vandy 3A Sigs have a fairly flat impedance curve, which would allow the use of tube amplification if that's of interest to you.

In your $3000 price range, look at used Rogue M-150 or M-180 monoblocks: 150wpc (although at 87dB, the 3A Sig might like even more power), 200k ohm input impedance.

How bout the CJ pre amp or used ARC LS5 or even a used Audible Illusions M3A about 800 bucks and an 100K input Imp ARC 100.2 for 1600 this combo put together should smoke all of what you are talking about for less than 1/2 the price
and Made in USA
Best JR

Audioconnection, Great recommendation John.

Have you ever heard the old saying "You can lead a horse to water"?

"10x rule is oft repeated fallacy"

For the stated output impedance at least. Looks like for tube amps you suggest 100x is a better rule.

Ok, so I visited my dealer this weekend and after listening to and speaking with him about Rogue Audio, I have decided to go for the 99 Magnum preamp (output impedance 350 Ohms) and the Stereo 90 amp (input impedance 200k Ohms). Amazing combo and fits perfectly withing my budget.

Thank you all for your advice!

FWIW, I would go for more than 90 tube watts with the Vandersteens.

FWIW, I would go for more than 90 tube watts with the Vandersteens.
Unsound (System | Threads | Answers)

Absolutely agree, which is why I suggested the M-150 or M-180 monoblocks.

One can buy used M-150 or M-180 monoblock amps for the cost of a new Stereo 90. It's a no brainer, IMO.

I'm sure extra power couldn't hurt, but honestly the Stereo 90 was driving a pair of 5As effortlessly and the sound was magic. Highly recommended.

Buying an amp based on what you hear on Vandy 5A speakers when you intend to buy Vandy 3A speakers is a mistake.

The 5A and the 3A Signature do not offer a useful comparison since the 5A speakers have their own powered subwoofers and the 3A speakers do not.

Good point Tvad. I did not think about it.

Actusreus, in the long run, the Rogue monoblcks will be a superior match with the Vandy 3A Signature speakers, and they will provide you with a wider choice of other speakers from which to choose.

I have no doubt the dealer you visited is strongly guiding you toward the Stereo 90. Consider the possibility that he is trying to make a sale, and that he may not have your best, long term interests in mind.

Unlike me, Tvad offers very sound advice.

I have no doubt the dealer you visited is strongly guiding you toward the Stereo 90. Consider the possibility that he is trying to make a sale, and that he may not have your best, long term interests in mind.
Tvad (Threads | Answers)

I should qualify this by mentioning that the dealer may be guiding you toward the Stereo 90 given the budget you have mentioned, and that given a bigger budget he may have recommended the monoblocks. He should be given the benefit of the doubt.

As I noted earlier, used Rogue monoblocks are essentially the same price as a new Stereo 90.

Tvad,
That's exactly right--I told my dealer what my budget was and that's how the recommendation came about. He actually started with the monoblocks, but recommended the Stereo 90 since it fit into my budget perfectly with the 99 Magnum preamp.
As a side note, he jokingly said not to tell the boss (owner) but in his opinion, which I trust, he said Rogue Audio amps were the best sounding amps they carry. That's pretty good considering that also carry Conrad-Johnson and BAT among others.

About used tube gear: I have no experience with tube gear; are there any considerations or risks when buying it used aside from possible warranty issues? Thanks.

About used tube gear: I have no experience with tube gear; are there any considerations or risks when buying it used aside from possible warranty issues? Thanks.
Actusreus (Answers)

IMO, buying used from Audiogon sellers is pretty safe. There's no trick to buying used tube gear versus any other gear.

Do some research about the seller. See if he/she has feedback, and is he/she has contributed to the discussions.

Ask specific questions about the gear. For example, ask the seller to describe specifically any cosmetic flaws and operational issues rather than to provide just a general description of condition.

Get serial numbers and check them with the manufacturer to see when the components were sold and if they have been serviced.

Obviously, most used gear is not warrantied, but in my experience, I have never had a single issue with a unit failing or requiring servicing within what would have been the remaining warranty period (and beyond).

Good advice. Thanks again.

You're welcome.

Good luck with whatever direction you go.