Krell Master Reference Amplifier

Any opinions on these amps?

I am in search of the best solid state amp in the world -- is the Krell Master Reference Amp it? Or would it be overrated?

Advice would be greatly appreciated?

Way, way, way, way, overrated and even further overpriced. The current "best" solid state amp for complete value and overall universal fit into any system, and best performance is the Plinius SA-250.

The only solid state that "betters" the SA-250 is the Goldmund Millenium at 10 times the price, but it is marginally better.

Best Wishes in your quest, Paul
There ya go, FINALLY, a person who has listened to all the solid state amps in the world and had time to rank them. I hope you could now give us the best tube amps also.
I have not had the opportunity for an audition. However, I have heard that the new amps from Jeff Rowland may be what you are looking for.
I believe the Mono amplifiers from Vitus Audio is a contender for the title.
The homepage is a little naked but just contact the guy and he will answer every question you might have and send pictures to you as well. I beleive that there is a picture of them at Frankfurt show coverage.
Paul, I'm just curious
1) How long did you allow the three amps you mentioned to break-in?
2) How long did you have the three of them in your system?
3) In what ways did you consider the Plinius SA 250 to be sonically superior?
4) When you say the Goldmund Millenium is marginally better; how would you quantify that statement?
5) How did you like the Halcro amp? Did you consider it to be a good value for the dollar, or is the Plinius considerably better than this world class amp too???

Thank you for all the hard work and auditioning you have done in this area so the rest of us can just accept your opinion.
two the best sounds I have ever heard was:

1) on HE 2001 in NY tube Lamm with dCS and Acuphase on JM LAM Grand Utopia's
2) on AudioShow in Warsaw 1998 four ML 33 + two ML 336 driving B&W Nautilius in fourwire configuration (do not remember the source).

But I not sure if this means that Lamm or ML makes the best amps. I'm not sure especially that Grand Utopias on HE 2001 sounded heavenly with Lamm and dCS, and the some speakers on HE 2003 with Bel Canto sounded just so-so for me.
So are Utopias the best speakers? I do not know it depends to what they are connected to, and who is the judge.
The some story about amps IMHO.
Greetings Folks,

Throwing too much credit my way loads too big a burden on just one person's opinion. A number of you already know but fair disclosure = we are a high end system designer/installer, but not a retail seller. That's why we have broad expereince with many brands over the last 23 years.

No, we have not had every solid state amp in the world ever made through our hands, but we have had a few. I will take sogood51 as someone who knows this industry and supports the recommendation as opposed to an ignorant sarcastic slap, because I stand by the recommendation and would be happy to discuss most other products on the market currently or up to 20 years ago.

Yes, we do carry some rankings for tube amps also and would be happy to share. But it is JUST an opinion. And no one pays us to advertise for them so we don't have any vested interest in suggesting one piece over another. We do our very darnedest to get the greatest value for any client given the boundaries they set. So, there tends to be "best buys" at all levels of budget. Yet, we personally strive to talk you out of gear, and especially cables and tweaks, that are more expensive for the sake of being expensive when clearly better sound can be had for less money.

Nrchy, your asking excellent questions. Your first two are a little tricky for me, because when we set up systems it is usually in one fell swoop and to designate a break-in time for which component breaks-in first or when an individual component is "done" breaking in is very difficult to pinpoint. Sorry, for this ignorant answer but I would question the manufacturer directly for information on a particular piece. We are all of the camp, components do need break-in periods universally. We have had both Plinius products and Goldmund amps here for years.

Regarding my humble opinion on the SA-250, the adjectives I would string together would be insignificant to the numerous reviews and technical measurements available, from far more credible sources than I. What I can absolutley tell you is this amp is the most flexible and forgiving on the market. It is a no-brainer to set up, no fancy computer configurations, no crazy wiring schemes or harnesses,etc. We have paired it with tube front-ends like Aesthetix and Kora. We have used harsh ended digital stuff like Krell, and more mainstream digital gear like dCS, Theta, and Audiomeca. The Plinius pulled the most out of each of those setups, showing more detail of specific instrument placement within the soundstage than any other solid state we have heard. We have driven all kinds of speakers including electrostatics, planar, and god forgive us horns. 2 ohms, 8 ohms, 16 ohms did not matter to the SA-250. Even real "goofy" speakers like Huff's with that omni driver, the Plinius never ran out of gas, we have never been able to make it clip when used as a monoblock.
My personal favorite is the Nearfield Acoustics Pipedreams match-up.

Also have used cheesy cables and chessy power cords all the way up to Nordost Valhalla, along with solid copper, solid silver, hybrid mixes of metals, even used hardware lamp cord once to prove a point once. Any way we sliced it the amp never gave up and even made hardware store lamp cord sound pretty darn good. The real test comes in your system, I would A/B it against all comers, at every price. Unless you personally can hear more from a more expensive product I would urge to save the money. I would suggest comparisons to Gryphon, Burmester, Boulder to see if you audibly justify a price difference.

Question four, you're right I can't quantify a difference. But it was one of those jaw-dropping experiences we see once every decade or so. One could walk into the soundstage and almost play the guitar in your own hands, park next to the clarinet player and here the subtle breaths inhaled to produce the music, almost do a duet with the soloist while standing right next to them. And then I woke up remembering the $100K+ price tag, but went home a better person for having one of those experiences.

Question 5, OOPS! You caught me! Halcro too, I am embarrassed I forgot, I was to wrapped up in the Millenium listening too much. The Halcro amps are as good as advertised. They will give you the same slam and punch on the low end that the Plinius does. The Halcro does have a lower noise floor than anything else - it is DEAD silent. Those who lean towards the Halcro spin it with more detail than Plinius. Those who lean towards Plinius call the same music drier with the Halcro. Plinius fans like the smoothness which Halcro fans call too warm and tube-like. It depends on which way you say tomato. Halcro really is an amazing product and doesn't deserve short shrift one might glean from my Goldmund meanderings. In bench testing Halcro's specs will better the SA-250 but again listen in your room with your system and compare the $$ Halcro about 4x more than the SA-250. Balance all variables, not just $$, but overall sound and matching to your current gear and cabling.

If others see it differently more power to them, this is only what we have found and we certainly have not got the market cornered on all the good ideas.

My Sincere best wishes on your Quest, Paul
Check out the Boulder stuff!

Thanks Paul. I think yours was an enlightening observation. I'm sure many are paying more and not getting that much more. In "drag-racing" speak, I think you put "negative poster"-- "back on the trailer".
Thanks to Paul and everyone else for your helpful comments. I really appreciate it.

I currently have the Pipedreams so it is interesting that Paul mentioned the synergy btw the Plinius and the Pipedreams. I have not heard the Plinius but John Marks at Stereophile, an opinion I respect, swears by them.

I have listened to the Halcros and think that while the noisefloor is very low, it is too dry and analytical -- lacking soul in my book.

I currently have the Krell FPB 600 and am happy with the sound but was considering adding the Krell Master Reference to power the midrange tower and using the FPB600 to power the subs of the Pipedreams -- may be overkill. I have heard the Master Reference briefly once at one of these audio shows and was very very impressed. Paul, I was wondering if you have had a chance to listen to the Master Reference? Also, do you generally like the current Krell signature sound?

I have heard the Boulder at a friend's house and I am not sure whether it was his poor setup or the amp, I did not think that the sound was better than my setup with the Krell FPB 600 (he had the Wilson X1).

I have not heard the Goldmunds.

I generally like the sound of Rowlands but have not heard their new gear? Does anyone here have an opinion?

Dear CCHP, the newer 700cx and 750cx Krell amps are using some of the technology found in the Master Reference and I wonder if you could get near the quality at a fraction of the cost of the Master? It's worth a listen. I've owned the 600C and now the 650's and I have been very pleased with the sound and performance. I also have the KPS-25sc and was humored by the "harsh" Krell digital comment. Until the Meitner DAC 6 I recently heard at the Home Theater show in San Francisco, the Krell was the best I've listened to. Good luck.
Hifimaniac, I withdraw, without equivacation, the "harsh" characterization.

We started with Krell back in the mid-eighties with the KMA series products. Krell has ALWAYS been of the highest build quality, no question. Their signature sound is by no means offensive. It is hard to quanitatively describe, I will try with describing feelings as best I can. We often came away from extended listening times (ninty minutes or more) with a tired feeling, a slight bit of fatigue. I am not talking about headaches or noticeable pain, but an "I missed something" quality. Back then we had IMF Studio Monitors and Beveridge Electrostatics, and before much attention was paid to cabling or power and home theater didn't really exist, unless cobbled together.

Over time we've had a fair amount of other Krell product through, most extensively of late, we spent quite a bit of time with the 650Mc monoblocks about 2 years ago. We had them hooked up to Pipedreams, JM Lab Utopias, Huff Omni, Wilson Grand Slams. When mated with the Wilson's was the worst combination resulting in very etched music especially when using very revealing cable like Nordost Valhalla. The one client who kept the Krells and Grand Slams used a darker cable, Transparent Reference XL, to tame the etchiness and I think it worked pretty well. As a group we wholly discourage the use of cable as tuning devices. But in this case the client insisted on the Krells and Grand Slams. The second client with this package had the Utopias. This fellow did everything but stand on his head to make the system right; i.e. different cabling, different racks and stands, different front ends but couldn't make it work for him and we remarketed the Krells for him and recovered his investment. Notable items he tried - Transparent Reference cabling, Purist Audio Dominus cabling, Nordost Valhalla cabling, star configurations of Richard Grays power conditioners, Ensemble power cords and conditioners, Shunyata King Cobra V2 and Hydra power conditioners, and many other non-system wide changes. BTW, when I mention a cable or power cord I mean the entire system was redone in that model mentioned not just one pair.
He also insisted on listening to music at HIGH volume levels. And I mean HIGH, within 7 weeks he had totally blown out FOUR pair of tweeters in the Utopias. The repair expenses were racking up quickly, getting those tweeters from France. To make a long story short the problem ended up being an oscillation problem with the amps. I freely admit we are over my head if we need to dissect the oscillation issue, I can't be of much help. Regardless, replaced the amps with a pair of SA-250 and not one peep out of the guy!!! Have no reported problems or shortfalls from him in the last two years.

From a perspective of many Krell products touched and two fairly recent installations, one positive resolution with cabling and one negative resolved by changing out the amps. Krell is not on our most recommended list. For similar dollars we find equal or better sound without some of the quirks. Yet, I would also observe Krell remains one of the most requested brands we see from clients.

For CCHP, I strongly urge you to keep the Krell for the subs! I believe we all agree subwoofers and/or base does not experience the subtle tonal differences in midrange and highs. Krells are powerhouses and that's just what those subs need. By sharing with us this is a pipedreams systems my conviction grows quite a bit stronger to at least audition the Plinius, if you don't you'll always have that nagging bothersome doubt that drives a lot of us nuts. If you have an established relationship with a dealer to loan you some Plinius I encourage you to avail yourself to the opportunity. If not, I would make some arrangements to trial something from our end; do the best I can to "put my money where my mouth is".

Without knowing your personal preferences I would have you consider a system that looks like this:
Krell - hooked to Pipe subs with some moderately priced lightning fast cable like the Nordost Red Dawn.
Plinius - connected to the towers with Nordost Valhalla or Siltech Generation 5 products.
For the purpose of this article I am forced to assume clean and sufficient power. (Yeah, I know it's a big assumption) but were trying to offer hope here.
Front end is a crap shoot these days with format wars and uncertain connections - hope to keep whatever you have and stay with upgradeable gear with companies known for support. i.e. Theta Digital, Goldmund, dCS.

Remember we are doing Nearfield listening so one can make this setup work in many, many spaces. If the room is still a problem we would add either Z-Systems RDP-1 or Tact RCS devices to finalize room compensation. Beyond that, racks, isolation items, etc. can be fine tuned at your leisure.

Apologies for the long winded post, but I insist on not being part of the Bash Krell crowd, as that's not the case.
Lamm 2.1 sounds incredible. Stereophile raved about it
Response to SDR Consultant:

Thanks for your comments.

Interesting...I also play my music quite quite loud at times and have blown the Genesis II midranges twice and the B&W801 15 inch woofer also twice -- with the Krell FPB 600. Maybe it is the oscillation problem that you are referring to.

I have listened to Krells in the past and agree that the sound is fatiguing, certainly not "harsh" but can be non-emotional. However, I thought that the current Krell amps are quite musical and dare I say it "sweet" in the midrange. Superb details, great soundstaging, and very balanced from highs to lows. I have never found it to be fatiguing and have not heard a better amp except for the Rowlands (obviously I have not hear a large number of amps so my comparison is limited to Levinson, Classe, Halcro, and Pass). I love the enthralling sound of tubes (especially with female jazz vocals), especially the VACs and the Jadis, but am realistic that given how loud I play selected portions of my music, tubes would not be the answer.

I am currently using the Linn CD12 as my front end and the Levinson 32. I am extremely happy with the CD12 but feel that the Levinson 32 is to dry (may change once I decide on an amp). I suspect that my cabling would need updating as I am using Goertz silver cables.

The other amp out there that was recommended was the Gamut? Any opinions?

I will try to get a hold of the Plinius to see how it would sound with my system. Paul, have you heard the new Rowlands?

Hi Cchp

I would be quite surprised if some of the mega watt tube amps from ARC, VTL, Manley, Joule, Wolcott, CAT, Jadis (JA-800), Tenor hybrids wouldn't supply you with all the power you need especially if bass duty is being provided by the Krell. Either you have an EXTREMELY large room or you listen at deafening levels if some of the above tube amps wouldn't work. Tubes in general have an immediacy and in general an upfront presentation that contrasts with the generally laid back presentation of SS that makes tubes appear to be louder watt for watt IMHO.

Nice posts SDR Consultant. Very detailed and informative input.
I'd bet the house the blowouts are that oscillation issue with the Krells.

Have not spent really any extended time with the newest Krell version, so I could not give any feedback at all.

Regarding the levinson 32 - Preamps have my nemesis for a long time. I think it is the trickiest piece of a 2 channel system to get right. In the last couple of years we have really focused on eliminating the piece completely and using volume controls in the digital side - on dacs or on pieces like the tact or rdp-1. (Typically my behavior - when I can't solve a problem to my liking I go around it.)

Gamut = very solid amp, and given the Pipes are notoriously efficient it may work, but I suspect it is going to end up too small for your application.

Fascinating you ask about Rowland. It's a brand we are not a dealer for, so I arranged to "borrow" some for a trial 6-7 months ago. A client was struggling with the choice between Plinius and Rowland. It was the most recent version of the 9ti but I only had one 250 he could take. He returned the 9ti s about a week later. He indicated it was the toughest call he'd ever made in his audio quest. He mentioned some days he liked one better than the next day he liked the other better. Ultimately what tipped the scales I think was money but he never admitted it. Not that he couldn't afford it but in his eyes, it was a dead heat and one couldn't justify the triple+ price of the Rowlands. It reminds me he never did want the second 250. He shifted the savings over to the front and selected the dCS Elgar+ and Purcell combo. (the Verdi wasn't out yet) can't remember his transport though.
Cchp notes "...(I) feel that the Levinson 32 is too dry.." My experience with a 32 was identical to the word: dry.

This was in a number of combos (none incl. Krell & Pipes, but INCLUDING equip Sdr refers to), strangely even with ML amps. Again, the proverbial exotic wires (Valhalla, Siltech, Transparent...) paraded through the system on a trial basis -- but, no cigar. This was with a number of speakers...

The systems sounded like they were "solving a mathematical equation rather than making music" (as a friend aptly put it). Especially so with wide bandwidth amps (Goldmund, Symphonic-Line, Spectral).

I never found out what I was doing wrong to this superbly engineered machine... For example, a CAT pre with stock tubes gave us more musical satisfaction; so did an old Goldmund 7.1 (??)

TO make this story shorter, you might wish to consider the pre-amp sooner rather than later... since you DID mention the issue (I don't wish to sound as if I'm discrediting ML).

OTOH I'd be wary of the oscillation issue; it's something to watch out for in wide-band amplification, but it seems here that your pre-IC-amp combo is losing stability somewhere... Not being electrically inclined, I wouldn't know how to go any further... (Sean maybe?).

As to the power amps, maybe a Symphonic Line (Kraft 250 classA) can be added to the Plinius / Halcro list, if only because its sound reminds me of a big Jadis (OK, it's less romantic and has supersonic extension which may be useless... but it has excellent current capabilities & can drive anything down to ~1,0 ohm, LOUD:)). Cheers!
Random comments:
Oscillation- if you're using Goertz cables do you have the Zoebel networks added?? Don't blame the amps prematurely...(It must be early am, I'm an apologist for Krell!) I also understand that the Halcro is more system dependent than a more "universal amp" like the Plinius. Several people I respect feel the Plinius SA-102 is the very best match for the new QUADs so the 250 deserves careful scrutiny. Again my hobby-horse right now are the Empirical cables and I would audition them immediately with eyes and ears open and wallet smiling.
I currently use the Krell 700cx which I had upgraded from a 600c. Prior to this I owned a Krell KSA250. Over a ten year peiord of lisenting to these amps in different rooms with different combinations of eletcrionics, cables and speakers (currently driving ML Prodigy's & using Transparent cables) I'm of the opinion that the 700cx is the best Krell amp I have heard, period. Without doubt the 700cx is not simply a power house: it is, for me, the most musically involving amp I have heard to date.

However I would also relate a listening experience I had around three or four years ago where I had a rare opportunity to compare a pair of Krell 600 mono's with VTL Wotan's. I have no bias either way when it comes to tubes or ss and in this extended demonstration the Wotan's, in my honest opinion, beat the Krell - and most surpisingly (to me) beat the Krells in the bass (the partnering equipment included JM Grande Utopia's and a Conrad Johnson ART. Having said this - both sets of amps sounded great and I would have been happy to take home either of them. But this brings me to the next point - compatibility: I've read a lot about what works and what does not work with Krell gear. Over the years I have come to the conclusion that there is a synergy when krell equipment is hooked up with other krell equipment (I use a Krell KPS20iL front end) - and this has to be a critical factor in the final selection process.
Paul do you have any experince with the Dynaudio Arbiter or the amps from FM Acoustics?

Thanks for your insights,