Ref 150 vs Retrofitted Ref 610

[dafos]

It may interest members, particularly ARC loyalists, to know that i was able to directly compare my ref 150 vs a kt 120 retrofitted ref 610, which on paper, seems like a gross mismatch, 150w vs 750w! Driving B&W 800d's, the ref 150 showed how far ARC has pushed the limits of the state of the art. The ref 150 was faster, quicker and in fact seemed to even go deeper in the bass, while at the same time, sounding sweet, smooth and oh so full. Soundstage size was a dead heat, a big surprise considering that the 610, being monoblocs, should have had a clear edge in this department. If the mighty 610 showed any advantage, it probably was slightly more composed when pushed playing complex musical material, as should be expected with all that massive headroom. Of course, if your speakers are extremely inefficient or your musical taste favors big orchestral works, hard rock or home theater use, then the 610's may better suit your needs. I'll probably be trying the ref 250 to determine if the extra 100w is worth double the asking price of the ref 150. But for now, I'm truly impressed how arcs stereo ref 150, in parameters that matter to me musically, surpassed the mighty ref 610. It also seems that simply retrofitting the older ref amps with kt 120's cannot bring the performance up to the level of the new ref amps whose power supplies, power and output transformers and those new Teflon caps were designed specifically to maximize the performance of the kt 120 tube.

 

[LL21]

Thanks, Dafos. Very interested read.

 

[jadis]

Very enlightening report, Dafos.

 

[microstrip]

Dafos,

I share your views about the REF150. I am currently listening to it and would easily subscribe your post replacing REF610 with VTL750s ...

The REF150 allows you to go deeper into the recording, presenting all detail in such a natural way that it does not hide other aspects. Every time I listen to a recording I know well with it, even just for background music, from time to time it grabs my attention to something new or enjoyable. One amplifier that also did the same to me was the big Atmasphere MA2mk2.

As you say, a surprising point is the way it handles the bass frequencies - deeper and faster than any other tube amplifier I owned.

BTW, there is one important thing that will get us the support of our solid state friends - the REF150 has FETs at the input ...

 

[tdh888]

Hi Dafos,


I would like to clarify if the REF 610's were plugged to the AVR 's (automatic voltage regulator) when you made AB comparison w/ the REF 150? If they were plugged whats the watt capacity of the AVR used?


Thanks,

tdh888

 

[LL21]

Has anyone compared the ARC Ref 150 to other amps which some of us (like me ) might know? ARC Ref 210? Any Gryphon? Krell? MBL? CJ amps? Unico?

 

[dafos]

Tdh, I did take that into consideration, and while my audio electrical circuit is connected to a 3kva Stavol AVR, the big 610's were connected to an unregulated 20 ampere independent circuit.

 

[dafos]

Iloydelee, I limited the comparison to ARC Amps that I either own or am familiar with. I'm confident, however, that the ref 150 together with the latest crop of ARC reference gear does not hold a monopoly in providing state of the art amplification and that similarly powered models of the brands you mention will provide stiff competition to the current ARC range. I'm sure my buddy Jack D will have a lot to say about this comparison vis-a-vis the excellent Lamm products. And I've also been reading great things about the beautiful copper heat sinked amp bearing Dan d'agostinos badge. I too welcome any feedback from others whom have had the chance to directly compare Arc products with other established brands.

 

[dafos]

Microstrip, your absolutely right about ARC's use of FET's in the input circuit, a design feature that they have in fact been implementing for some time now. Further, their current range of class D amps seem to be reaping accolades in several printed and on line publications.

 

[Steve Williams]

It may interest members, particularly ARC loyalists, to know that i was able to directly compare my ref 150 vs a kt 120 retrofitted ref 610, which on paper, seems like a gross mismatch, 150w vs 750w! Driving B&W 800d's, the ref 150 showed how far ARC has pushed the limits of the state of the art. The ref 150 was faster, quicker and in fact seemed to even go deeper in the bass, while at the same time, sounding sweet, smooth and oh so full. Soundstage size was a dead heat, a big surprise considering that the 610, being monoblocs, should have had a clear edge in this department. If the mighty 610 showed any advantage, it probably was slightly more composed when pushed playing complex musical material, as should be expected with all that massive headroom. Of course, if your speakers are extremely inefficient or your musical taste favors big orchestral works, hard rock or home theater use, then the 610's may better suit your needs. I'll probably be trying the ref 250 to determine if the extra 100w is worth double the asking price of the ref 150. But for now, I'm truly impressed how arcs stereo ref 150, in parameters that matter to me musically, surpassed the mighty ref 610. It also seems that simply retrofitting the older ref amps with kt 120's cannot bring the performance up to the level of the new ref amps whose power supplies, power and output transformers and those new Teflon caps were designed specifically to maximize the performance of the kt 120 tube.

At RMAF this year, Dave Gordon told me that ARC discontinued the Ref 610T for the new Reference 250 because the latter is a better amp

 

[dafos]

Hi Steve, philip's been raving about your great set up in his recent visit to the bay area. Hope to be able to visit your abode as I too am a frequent visitor to your part of the country. Regarding the ref 610's demise, ARC followers here are eagerly awaiting, or the better word may be assuming, the release of a new ARC flagship amp which has already been unofficially christened the ref 750.

 

[Steve Williams]

Hi Steve, philip's been raving about your great set up in his recent visit to the bay area. Hope to be able to visit your abode as I too am a frequent visitor to your part of the country. Regarding the ref 610's demise, ARC followers here are eagerly awaiting, or the better word may be assuming, the release of a new ARC flagship amp which has already been unofficially christened the ref 750.

That's interesting as you must know something that I don't. As stated Dave Gordon told me that the Ref 250 is a better amp than the 610T but a new flagship would be interesting

BTW,not sure how it is in the Philippines but I can tell you that when I owned the Ref 600 Mk lll with the ARC Ref 3 preamp, there were a total of 70 tubes. Listening in the summer necessitated the use of a swim suit as the room became so hot. Ultimately I installed a 3rd dedicated central AC in my home, servicing only my listening room. When I went SET the problem was obviated.

BTW, you are always welcome to stop by on your next SF visit

 

[tdh888]

Thanks for the reply. We must tell our friend who uses a 610 also to try the new ref amps in his system. He heard that 610 with the kt 120 in his system and was able to compare it to his ref610 still using 6550's and according to him there's no compArison, his 6550 equipped 610 is better.

 

[dafos]

I believe at the time the comparison was made, the retrofitted kt 120"s were absolutely brand new and on top of that, one amp was apparently not properly biased. On the other hand, we all know that our friends 6550 610 has seen heavy use thru the years so in the local jargon, "batak na batak" na, or loosely translated, very much broken in, so it was not really a fare comparison. Further, the former owner of the retrofitted 610 is very happy with his new ref 250 and does not in any way miss the 400w of power he gave up when he pulled the switch to the newer amp. Btw, I trust and hope that any technical issues you've had with your Arc gear has been properly resolved. As for me, at 225 hours for the 150 and 180 for the ref anniversary, the combo is indeed performing beautifully and even if no further improvement takes place till the 600 hour mark that Arc claims we must wait to enjoy the benefits of their products' full sonic glory, I'd still be fully content with the combo's current performance.

 

[microstrip]

Do you know which speakers were used in these comparisons? Although I would love the idea that the REF250 sounding better than the REF610, it is not something I accept easily. Every time I listened to the REF610 - with several speakers, such as The Sonus Faber, Alexandria, MAXX3 , Magico's M2 I found it something unique. Only the tube count, heat and cost have kept it away from me. But currently a pair of used REF610T is cheaper than the REF250's.

 

[tdh888]

Hi Dafos,


Thanks My ARC gear that has been having technical issues repeatedly is my pair of Classic 150.As of this time (knock on wood ) they are in good health after the thermistors in one amp were replaced. I cant believe that it sounds more powerful than my D250MK2 servo and more musical & liquid because of its triode configuration. Among my stable the pair of the Classic 150 are the one's I often listen to. Im glad everything is working out for you but Im sure when your equipment reaches the 600hrs mark you will be in sonic nirvana!

Microstrip,

In our friends system his REF 610 drives also a B&W 800 Signature. The former owner who replaced his REF 610 w/ a REF 250 uses the Wilson Alexandria.Unfortunately I have not heard the REF 610 w/ the Wilson's. Im also bias w/ REF 610 and if I have the money I would get a pair instead of a REF 250.

tdh888

 

[mep]

It's funny how soon yesterday's super amp is thrown on the scrap heap. It seems the main advances in tube amps recently are the KT-120 output tube (and time will tell whether or not that it is a "super tube") and teflon capacitors. Both CJ and ARC as well as others are now using some form of teflon caps. The fact that ARC and CJ have both switched over to the KT-120 says a lot. They have both been wedded to the 6550 for many years and you don't give up your bread and butter without careful consideration.

If the KT-120 and the teflon caps are the reason for the improved sound, there's no reason why ARC can't scale it up in power and come out with a new flagship power amp.

 

[microstrip]

It's funny how soon yesterday's super amp is thrown on the scrap heap. (...) .

I would be very pleased to have access to such scrap heap. , but IMHO the REF610 will never be scrap heap. The REF250 can be better sounding, but it will never have 650W or be able to drive some speakers the way the big cousin did.

Look at the previous and current sales history of ARC powerful amplifier such as the D250 , Classic150 or REF 600 at Audiogon blue book - they keep value as well as certain famous solid state very heavy class A amplifiers and represent excellent value for money at their used prices.

 

[dafos]

Maybe I got a bit carried away in my praise of the ref 150 and/or "bashing" of the 610 if that's the way some may look at my comments. The ref 610 remains a great super amp, arguably one of the best ever. What greatly surprised me though was how the hugely power disadvantaged ref 150 matched the 610 tit for tat and in some cases bettered it. But I totally agree that at less the asking price of the ref 250, a used 610 is indeed a great bargain, particularly when used in a system that can make full use of it's prodigious power reserves. Tdh, this may be a great opportunity for you to complement your stable of Arc classic superamps.

Steve, with the average annual temperature in the Philippines ranging between 25-35 degrees Celsius in the shade coupled with 90% humidity and having one of the most expensive electricity costs in the world, owning and operating the ref 610 can truly be an expensive proposition. Outwardly, I see a total of 36 power tubes and 6 signal tubes, with more tube regulators hidden deep within it's tower case. Couple that with at least 20 signal tubes and 2 6550's of the ref anniversary and yes, the tube count does indeed climb. While in my place, even with a 2.5 hp ac running at full blast, I felt the surge of furnace like heat whenever i came within a foot of any of these behemoths. But ive had solid state amps in my place, like the huge pure class A Pass Lab amps that rival the heat generated by the 610. But I guess serious audiophiles the world over will always be willing to put up with the seemingly impractical and even tedious task of owning and operating high end gear for a taste of audio nirvana. And frankly, despite all the power tubes, biasing the 610's is a simple and straightforward task.

 

[JackD201]

BTW,not sure how it is in the Philippines but I can tell you that when I owned the Ref 600 Mk lll with the ARC Ref 3 preamp, there were a total of 70 tubes. Listening in the summer necessitated the use of a swim suit

If there are no pics, it never happened.

Dafos, me have lot's to say? Nah. I haven't heard the 150, 250 and only heard 610s briefly with unfamiliar systems. I'd be the worst judge.

The 610 has reportedly had issues because of the biasing configuration employed. Tough to get all the tubes powered and powering properly. This could explain a lot of what you're hearing in the power/performance department when you compared them. These reports did not come from the two common friends who've owned or own 610s. I always wanted to ask if they were/are having problems in this regard but could never build up the nerve. On one hand if they were enjoying what they were hearing it would have just served to spark up audiophilia nervosa, if they were having problems, I'd have rather Senor Lito do the trouble shooting. I other words, just wasn't my place to ask.