Amplifier ideas with KEF Reference 1

@keoliphant
If you can find a pair of Classe Delta CAM 600 monoblock amps try to have a listen to these amps in your own setup and system. These amps have been discontinued last year and few Classe dealers might still have them on display or in b stock and they can be had at discounted price today. Their original retail price was $14k/pair. You can still keep using your PS Audio BHK Sig preamp and Direct Stream DAC.

The Classe Delta CAM 600 monoblock amps are class AB design and huge and heavy but they run cool due to superb internal heat management system they have in there. Classe uses ICE Tunnel to dissipate heat which is executed outside the signal path and does not interfere with the amp's circuitry. 
These amps sound and perform phenomenal very musical very smooth refined and doesn’t get in the way of the music. The amps don’t induce its own sonic coloration like some other high end amplifiers do. Your speakers simply sound like themselves. You should read reviews on these Classe CAM 600 monoblock amps. The Classe CAM 600 monoblock amps received many outstanding reviews from several different hifi reviewers from many different hifi magazines and sites. John Atkinson of Stereophile simply said that these are the best sounding amps he's ever reviewed or the best amps ever made period. I know it was pretty bold statement he made, and one reviewer from The Absolute Sound made similar statement regarding these Classe Delta CAM 600 monoblock amps. 
In reality these Classe CAM 600 is spectacular sounding amp and run cool but big massive in size and very heavy. 
Dynamic headroom and bottom end extension and control are excellent.
The Classe CAM 600 excels in extracting musical details and nuances and information. The tonal is neutral and balanced across the entire spectrum with a touch of warmth. The noise floor is one of the quietest I’ve heard from any high end amplifiers. The amps are dead quiet and the music emerges from a dark black silent backgrounds.

These amps look very stylish too imo.
I happen to own these Classe CAM 600 monoblock amps in my dedicated home theater room driving my front speakers (B&W 800 D3). I have also tried the amps for playing music and they sounded fantastic for both stereo music and high end home theater setup.

One time I dragged these Classe CAM 600 monoblock amps to my dedicated stereo setup in a separate dedicated listening room and pair them up with my Magico M6 speakers that I have in there and sounded wonderful. I compared them with my Dan D’Agostino Momentum M400 monoblock amps (2 pairs) that I normally have in my dedicated stereo setup and while my D’Agostino Momentum M400 edges out the Classe CAM 600 but the Classe CAM 600 are bargain considering the price difference between these two amps.
My Dan D’Agostino Momentum M400 monoblock amps retail for $65k/pair and I have 2 pairs bi-amping the Magico M6 speakers. And I’m using the Audio Research Reference 10 linestage preamp and a complete full DCS Vivaldi stacks (Vivaldi master clock, Vivaldi upsampler, Vivaldi DAC, Vivaldi CD/SACD transport) as my digital front end source components. Even when I slipped the Classe CAM 600 amps in my high end reference two-channel setup the Classe simply performed wonderfully driving my $176k/pair Magico M6 speakers.

You should also consider other options such as the Audio Research Ref monoblock amps, CH Precision, Soulution, Audionet Max monoblock amps, Tidal, MBL monoblock amps, Burmeister, T&A, Gamut, Virus Audio, Constellation Audio, Halcro, higher end Naim separates eg Naim NAP 500 DR amp + Naim NAC 552 preamp + various Naim streamers + DAC separates. You will probably love how Naim gears sound. Even their lower end series or entry level series sounded very musical.

Oh finally I forgot to mention about Devialet gears. I highly recommend any Devialet. If you go this route you won’t need your PS Audio BHK Sig preamp and Direct Stream DAC. Devialet is basically all in one solution (streamer/DAC + pre + amp). Fantastic products. It starts at around $10k plus for the Expert 130 Pro to around $40k for the Expert 1000 Pro.
I happen to own the the Devialet Expert 440 Pro, which is right below the 1000 Pro for my master bedroom setup paired with the Wilson Audio Duette ll stand mount speakers.

One last thing I would like to recommend to you is the new Linn Klimax DS with Katalyst DAC architecture with its Linn Klimax Solo Chakra 500 monoblock amps. But this setup will cost you around $55k. $30k for the new Klimax DS (with Katalyst DAC architecture) and another $25k for the Klimax Chakra Solo 500 monoblock amps. With this setup you wouldn’t need the PS Audio Direct Stream DAC nor the PS Audio BHK Sig preamp.
The new Linn Klimax DS (with Katalyst DAC architecture) will blow away the PS Audio Direct Stream DAC. They are in different league. The Linn Klimax DS has built-in volume control (preamp) so the signal path is made as direct and short as possible. The new Linn Klimax DS (with Katalyst DAC architecture) is the best sounding digital streamer/DAC I’ve heard for under $50k. You will literally have to step up to MSB Select Two DAC ($150k) or DCS Vivaldi full four separate stacks ($125k) like the ones I have, or the Esoteric Grandioso full separate stacks ($100k+) in order to outperform the new Linn Klimax DS with Katalyst DAC architecture which retails for only $30k. This is a single box solution for you : digital streamer/DAC/preamp in a single chassis.

Hope this helps. Do not hesitate to ask any questions.

Thanks for everyone's input. I just started a new thread specifically on the aci600 vs Black EX separates..... Hoping to learn more. I'll report back once the system is in place!

Interesting posts by all. Thanks for the dealer participation by @audiotroy  and @everest_audio  and their individual takes on the OP's questions/situation.

@keoliphant   Sounds like you have made a choice. I'm interested in hearing how the amp-speaker pairing work out in your office.

 All the best.

You seem to have a lot of expert advice. I have owned many Kef's and the magic mid is the take away for me.   

I'd concur that some recent integrated amps may be the ideal choice to support the great mids.   

You should also audition the Constellation Integrated 1.0 and the Moon 600Vi2.   

keoliphant, Bel Canto has told me that the Black EX separates will play to a higher level than the ACI 600 as long as you make sure you're using a very high quality XLR cable between them.

I'm thinking it's between the Bel Canto ex black separates or the Bel Canto Black ACI6000 integrated. I don't want to worry about heat in my office again, and my wife approves of the looks (if they migrate home).

Similarly priced.... Can't seem to find anyone who's a/b'd them. Thoughts?

audiotroy, no sour grapes at all. Carrying T+A as a brand didn't work out for either of us and that's fine. And, to be clear, I'm not knocking T+A at all. I highly respect T+A as a quality brand. In fact, on another forum in the past few days, when someone was looking to add a particular T+A piece to his system, I highly encouraged it as I felt that particular piece was absolutely spectacular for the money. I just call it the way I see it. Someone else may disagree and I'm okay with that. The DAC 8 was fed the exact same files via the Melco N1A/2 as the Bel Canto Black EX. Some redbook, some high-res PCM, some DSD, but not comparing MQA as the DAC 8 DSD doesn't have MQA decoding. So, no, I wasn't running something like DSD512 via HQplayer. But, still, I'm comparing $15K USD gear versus $15K gear and you don't need a high quality XLR cable with the Bel Canto or an extra power cable.

As a side note, the Bel Canto Black series is in a whole other league compared to what you may know about Bel Canto. It is definitely playing in the big leagues. You should hear it sometime.

Everest could it also be sour grapes since T plus A dropped your dealership?

And with a Dac 8 how did u feed it? The Dac 8 running Quad rate Dsd sounds unbelievable running 16/44 it is good not magical.

Is the Bel Canto better maybe it is and maybe it isnt we havent heard a digital amp that sounds better then a pure class a/b amp and until we test it we wont pass judgement. 

Dave and Troy
Audio Doctor NJ

The Bel Canto ACI600 is $25K USD, but I'm talking about the less expensive new Bel Canto Black EX at $14,990 USD. Definitely a fair comparison. 

Everest I don't think you have your facts straight, when does a $25k Bel Canto integrated amp compare to a $11k T+A  one, if you factor in the cost of a Dac 8 which is $15k for the combo not $25k! Even if you figure $3k for a good interconnect I get $18k not $25k!

The T+A PA 3000 at $18k would be the comparable piece, also with the DAC 8DSD for $4k you would still be a $22k, want to do that commparison vs the Bel Canto?

If you are comparing products a $25k one should be discussed with a similar set of other components at a somewhat similar price point.

Then we will have a fair horse race. 

Dave and Troy
Audio Doctor NJ

Agreed that the T+A PA 2500 R is a great sounding piece, but I personally feel the Bel Canto Black EX integrated sounds a chunk better for sure. The Bel Canto has more body and fullness with the same level of resolution and drives the bottom end with more authority, but is still very well controlled. Plus, the Bel Canto has the benefit of a superb built in DAC with PCM, DSD and MQA capability. A lot of the Bel Canto quality comes from their superb DAC in this piece and Ethernet input. Not knocking the T+A at all, it is an excellent piece, but I just find the Bel Canto exceptional. Before moving to the Bel Canto Black EX in my system with the ATC SCM40, I was using the T+A PA 2500 R with the T+A DAC 8 DSD and the GutWire UNO-S XLR interconnect between them which is an incredible cable. The T+A integrated with a very good DAC and cable will definitely cost more than the Bel Canto integrated. Of course, this can be taken with a grain of salt, as should be the opinion of anyone, but this comes from living long-term with both in the same system. With that said, I haven't heard the Bel Canto Black EX with the KEF Reference 1, but I can't imagine the combo not working well. 

Note: as much as I'm a Bel Canto dealer, I have nothing to gain by mentioning this as keoliphant has his own Bel Canto dealer. Just lending my 2 cents as someone with extensive experience with both products.

Keoliphant,

We are a long time Kef Reference dealer and one of only 5 dealers in the entire country with almost every Kef product line represented, we have the Blades, Ref Ones, Ref Threes, Ref 5, R series, T series, Q Series, LS 50W, LS 50p, so we are very up on KEF.

The Ref 1 when paired with great electronics are mind blowing how real music can sound and they work well in a small room due to the bass tuning tubes and wide lateral dispersion of the Uni Q.

If you are looking for an exceptional amplifer in a small package that gives off little heat then the T+A 2500R might be your ticket.

The T+A gear is exceptional gear and their products are usually among the best sounding brands of gear out there.

 If you are not familiar with the brand T+A is the largest single high end company in Germany, with a full time staff of 110 employees and 14 full time engineers T+A has the resources to develop some really outstanding gear which is built up to German standards of superb craftsmanship and because of the companies large size they can afford economies of scale which enable them to use exceptional parts,  and still keep the pricing affordable. 

A unique aspect of the HV and R series is the High Voltage circuitry which runs solid state devices at much higher rail voltages which lowers distortion and helps create a more tube like sounding solid state product.

The larger HV 3000 a $18k integrated amplifier will most likely far outperform your PS audio gear, the PA 3000 HV was compared by Allan Tafel in the TAS to a $120k worth of CH Precision gear and he was having difficulty telling the difference.

http://www.theabsolutesound.com/articles/ta-pa-3000-hv-and-mp-3000-hv/?page=3

here is the quote that got us to bring in the line:

"Similarly, the PA3000 not only competes directly with integrated amps that run all the way up to $50k, it holds its own against $120k worth of Switzerland’s best separates. This is a component that’s not to be missed.

But these HV models not only stand up to their Teutonic brethren, they sound just like them. What T+A has done is to make it possible for audiophiles of more modest (though still significant) resources to get in on the extraordinary build-quality, sonic merit and character, and sheer musical enjoyment of the Swiss School. And that is surely a promise fulfilled."

The PA 3000 runs warm not super hot, and is compact. The less expensive R series 2500 integrated at $11k offers much of the same sound but not quite as good as its bigger brother.

T+A is a bit hard to find currently we are the East Coast dealer NY/NJ but there are a handful of good dealers and more signing up.

We have run the Ref ones with the 2500R and was exceptional we have run the KEF Blades on the PA 3000 and the sound was truly magical.

Dave and Troy
Audio Doctor NJ

@keoliphant Based on your responses I would think the Luxman 509x will be what you end up with. I never gave too much consideration on looks for audio gear but that Luxman has super model looks to it. The loudness button on the Luxman 509x would also be very useful to my office setup when I am working late at night.

I should also mention that I did hear the KEF Ref 1 sound awful once at a dealer. That was when it was played in a room about the same size as yours. The speakers were facing a wall full of glass. It was unbearably bad and I was shocked the dealer simply did not flip the room configuration around. My take away from that was that there is a lot of bass coming from the Ref 1.

I also wanted to mention that the Magico A3 speaker maybe an interesting choice for your office.

I found that when I work my long hours in my office I do not want too much bass hitting my ears. The LS50 and the Audience 1+1 are great at this for a small to medium size rooms.

Lots of positive reviews on the Lyngdorf. If it were me, I would first replace the pre/amp and keep the LS50. You might just get enough incremental improvement from your LS50 by adding room correction that you may be satisfied with the results. Keep the rest of the budget for the next major upgrade.

keoliphant

They are fairly hard to drive as in the power region of the bass they present a load to the amp of around 3.2ohm and that's broad from 50hz to 200hz.
Look for amps that are happy seeing 3ohms all day as many tube,mosfets, and Class-d may not do the job.
I would hunt out linear amps with beefy power supplies, that use multiple BJT (bi-polar) output devices. Like John Curl designed Parsounds, Krell, D'Agostiono, Gryphon, some Classe's, Mark Levinson. ect 

https://www.fidelity-magazin.de/2016/08/23/kef-reference-1-messungen/

Cheers George

The Hegel 590 is a killer amp, heard recently running blades! Incredible. regarding the looks, understated yes, but personally I’d rather this than the extra expense going into looks and style.

also consider the Arcam class G kit, P/A49 etc... again a very good amp, and works well with the Ref 1,3 etc...

Thanks for the insight and ideas yyzsb. I'm with you, it's just money..... And considering that I spend more time at the office than home, my office setup should be killer.

I'm thinking whatever I choose needs to have the wife acceptance factor in case it comes home. My wife hated the looks of the wyred, benchmark, McIntosh, and Hegel....the bel canto black ex (integrated or separates) and the Luxman 509x were her favorites so those are my final options. 

Decisions, decisions!!!

@keoliphant I have also invested a little bit of money into my office system. I originally had LS50’s powered by PeachTree Nova 150 integrated. I moved that system to the bedroom and now have the Audience 1+1 V2+ speakers driven by a single Benchmark AHB2 amp in the office. The Audience 1+1 speaker has a clearer sound than the LS50, though I love both speakers equally. The LS50 has a little more heft to it.

You may want to do a little bit of research on the Audience 1+1. I was going to get the KEF Ref 1 for the office but decided against it because I would eventually end up with 3 KEF based systems. I wanted a little more speaker diversity and I am so glad I got the Audience 1+1. It is a different sounding speaker from the small KEFs.

http://www.theabsolutesound.com/articles/audience-clairaudient-11-v2-loudspeaker/

I heard the KEF Ref 1 with the latest Wired4Sound monoblocks and it was fabulous. I ended up staying and listening to that system longer than I planned. Seriously good sound and not too expensive.

https://wyred4sound.com/products/power-amps/mono/sx-1000r

The Benchmark AHB2 would also be a great amp to pair with the KEF Ref 1’s though I am not sure if it would meet your needs for a warm sound. This amp has no sound to it and maybe the quietest amp available at ANY price.. I would recommend 2 of these amps in monoblock for the Ref 1 ($6k total new). Maybe a little over the top in power but the amp is so cheap for the performance. It also has a shocking small form factor which you will appreciate for an office. Your PS Audio DAC will work well with it. I use the new Benchmark DAC3L

https://www.dagogo.com/benchmark-audio-dac3-dx-ahb2-amplifiers-review/

My final audio purchase will be KEF Blades for the living room. I am thinking about some different ideas to drive them or getting a second Benchmark AHB2 and running them in monoblock form with the Blades. There are some A’Gon users successfully using the AHB2 amps in this setup. If I get a second AHB2 and use them in the living room I am thinking of splurging for the Luxman 509x for the office. BTW - I have a budget of 30K for the living room amps so I have many choices.

I also use Audience cables and speaker wires. I will get the top of the line Audience wires for my living room system,

I have heard the Hegel 360 with the KEF Blades and that integrated would also work great with the Ref 1’s. You would not need the Hegel 590. The Hegel really makes sense from a practicality perspective and also sound wise. However, I do feel the AHB2 sounds better than the Hegel (for me). I was lucky to have an almost private 2 hour audition with the Blades and H30 | 360 | Roost amps from Hegel. The H30 and 360 sounded very good with the Blades but something tells me the AHB2 in mono maybe better.

The PeachTree Nova 300 also would work with the Ref 1’s. Maybe not as great as some of the others I have listed but you are supposed to be working in your office (correct)? This integrated should work well enough and I may also get this if I don’t do something crazy and buy the Luxman 509x for the office.

I have actually heard the Kef Ref 1 with a few more amplifiers that escape me now. I do not think this speaker is too difficult to drive but I would try to use more than 100 wattts.

I think there are a lot of really good amplification choices these days without having to break the bank. The 10K mark for office amplification is a little tough to justify but it is just money. The stuff I have listed all run cool and some are very small in form factor.

@d2girs: I haven't heard the KEF Ref 1's but (1) I have enjoyed my KEF LS50's, (2) they're pretty well reviewed, and (3) I can get a killer price on a new pair. What are you thinking in that price range for bookshelf speakers? I don't want to spend more than $5000. As for Ref 3's, they won't fit in my office.

@jwpstayman: If budget would allow, I'd go for the T+A 3100HV integrated. $17K is my all in amplifier budget. I'd prefer to keep it under $10K.

@drrsutliff: I haven't listened to the Ayre equipment to any great extent. A local dealer pairs it with Magico speakers...the combination was too dry and thin for what sounds good to my ears. Not sure if that's Magico or Ayre....or both!

Ayre AX-5 Twenty.  Loved this combination when I was able to audition recently at a private home.  I am currently using an Ayre VX-5/20 to power my KEF LS50s while I am auditioning for new full range speakers and I am constantly amazed at the synergy.

Yes, I believe the Wireworld Gold Eclipse 7 XLR would work. I'm a huge fan of the GutWire UNO-S XLR myself. The best I've used. 

In regards to the T+A R1000E, I'm sure it would work nicely, but not in the league of the Bel Canto Black EX. It is less money though, but the Bel Canto Black EX integrated still fits within the listed budget. As a side note, I used the T+A PA 2500 R with the T+A DAC 8 DSD before the Bel Canto. This is a higher end combo that the R1000E, but even then, the Bel Canto is a nice step up in my opinion. 

Do yourself a favor and try and listen to the T+A R1000E integrated with DAC and streaming services.  It runs cool, has a very high SQ DAC and will easily drive the Kefs.  Should fit right in with your tight and fast bass with great musicality and will easily fit your budget ( around $8k).  Good Luck!

Follow up question Everest. You mention needing a really good XLR cable for the Black EX separates. Would a WireWorld Gold Eclipse 7 (XLR) suffice?

Thanks!
Ken

We haven't had it for a very long period of time,so I haven't tried it with a wide variety of models. Love it with the ATC SCM40. Also tried it briefly with Dynaudio Special Forty and Alta Audio Lelantos. Performed very well with all three. 

Thanks Everest. What speakers have you found pair best with the Black EX integrated?

I'm a big fan of your first listed choice, the Bel Canto Black EX integrated. It's what I run in my own system. Disclosure: I'm a Canadian dealer.

The Bel Canto Black EX isn't analytical sounding at all. The signature is neutral to just slightly warm with powerful, deep and controlled bass. My ATC SCM40 speakers haven't sounded this powerful at the bottom before. Mids and upper end are very smooth. The DAC section is really the key to this piece. World-class DAC section including full MQA decoding from TIDAL. You'd have a very simple system. I feed the Ethernet input on the Bel Canto Black EX with a Melco N1A/2 via a Wireworld Platinum Ethernet cable and the combination is incredible.

Sure, the Black separates would be a step up, but at considerably more cost and you'd need a really good XLR cable between. With that said, the Black EX integrated is a very high end performer on its own and plays in an elite crowd.

The Hegel amps are known to work very well with KEF and I'm a fan of the H360. Excellent value. But, if the Bel Canto is in your budget, it definitely plays at a higher level, which it certainly should as per the price difference and fits the qualities you're looking for.