Preview of ARC's Ref 250 monoblocks from The Audio Beat...

[enatai252]

Originally Posted by SRT-10 Viper

I've heard from a pretty good source that ARC might show a REF DAC8 prototype at CES.

I also heard they may show a Reference DAC and have heard some rumored specs...I went ahead and ordered one...hopefully some of the info will be public soon.

[New guy]

Originally Posted by cmalak

New_guy...here is my stab at your questions. Others, I am sure, will join in with their perspectives:

1. It is hard to generalize because every amp is a function of it's circuit design, parts used, implementation of that design, etc...In general, tube power amps, will deliver more midrange realism/presence, a more immersive/3D sound, a more liquid/smooth presentation (which denotes tubes are more capable of fully fleshing out a note's attack, fundamental and decay), and overall to my ears a more realistic presentation overall. What they do not do as well vs. their SS brethren is control bass woofers in a speaker. So bass will be less articulated and usually less deep. In the case of the Ref 250s, the power supply is overbuilt and should deliver plenty bass as well as deliver the advantages above.

2. The output tubes (KT-120s) in the Ref 250s should last you 2000 hrs. The 6H30 tubes in your Ref 250s and in your Ref 5SE should last between 5000-10000 hrs.

3. If you retube them from ARC, I believe they will charge you $400 per matched quad. So $800 per Ref 250 amp or $1,600 for the mono pair. I think you can get the KT-120s for half that from reputable tube suppliers.

4. That is a tough one to answer as the Revels are a tough load. Will the Ref 250s drive them? Yes. Will it run out of steam when played very loud in dynamic passages, I don't know.

My guess is your Krells are probably a better match with your Salon 2s. If you can get to audition the Ref 250s with your Salon 2s that would be preferable. I would use very dynamic music and played loud to test the amps under extreme conditions and pay attention to whether the soundstage collapses, images start to smear or constrict in the middle of the stage, and obviously if the sound starts becoming harsh and distorted then the amps are clipping for sure and you want to ease off of the volume control.

For most moderately tough loads, the Ref 250s should have no problem. The Revel Salon 2s might give the monos a challenge. Not sure.

Hope this helps.

Cyril and Mike,

Thanks for your input and suggestions. I like what tube does for vocals but I have alway been concerned about the the end low, especially coming from Krells.

I borrowed a pair of Ayre MXR monblocks rated at 300W/ch a few months ago to drive the Salon 2 and they did not mate well with the Salons. The highs and mids were wonderful but there was not much bass. I was very surprised that 300W was not enough. My room is a moderate size and I don't play loud or listen to rock music. I guess it also depends on how well the amp handles lower impedance loads as well. The Ref 250 at 250W is a big concern with the Salons.

Given the cost of tube replacement, it might not make much sense to use the REF 250s for movies.

I will have to give more thoughts about the Ref 250s and actually try to listen to them at some point.

Thanks again.

[Dafos]

New guy, I not familiar with the music you listen to or how loud you play but I believe the ref 250 should have more than adequate power to drive your revels. I'm using them to power the equally hungry, sealed box magico mini 2 and I've never seen the power meter hit the 250w level, even at quite high levels. Neither have I heard them sound strained.

[TOGA]

Hi new guy, I have been thru these question before.
I haven visit AA for along time due to work, but your questions, I really have to join.
I have Salon2 too and looking for new amps as well. REF250 is on my short list too, but
I really not sure they will drive Salon2 well. Sometime ones never see true capability of Salon2 deep bass
And dynamic punch power until they drive it with capable amp to show this. I first drove them with Levinson No 436, 350w mono
. Nice sound but unable to compare to when I heard Salon2 driven by Levinson No 53 or Moon W7m.
I was about to buy no53' but later I sold Levinson system to buy Moon instead and currently using ARC Ref pre amp
withl Moon's powerful mono block. As I feel Moon tonality is far from rich and dense in the lower register, I am
Thinking about new amps. I Found out that Ref 250 tube replacement will be costly, and premature tube failure
Can be expected, and not quite sure about how well 250 watt of tube power will be enough for Salon2.
So here is my plan. a new easier to drive speakers, or a new REF750 from ARC, or Dan s Momentum.
It would be great if 250 watt from REF 250 is happen to be fine, because cost of Ref 250 plus cost of tube replacementFor life is still
Less than cost of Momentum amp.
For your info. I've tried big SS amps that I find not push Salon to its best dynamic capability as following
Pass X350.5 , very lovely sound until music require great speed and more impact.
Mcintosh MC402, .. Is this really have 400 watt ???
Pass XA 160.5 , only this one, that matched or may be exceeded my Moon W7M power. Especially when pair with XP20 pre amp.
but when I pair XA160.5 with my ARC pre amp, much of the punch is reduced.
So I keep Moon Amps as it better matched to ARC preamp.
As soon as my work schedule is less intense I will bring Ref250 home to try with Salon2.

Cheers

[New guy]

Dafos,

I listen to mostly jazz and classical music at moderate level and in theory, 250w should be enough but my recent experience with a 300w amp was disappointing.

[New guy]

Toga,

Thanks for taking the time to reply with your busy schedule. I too have the same concerns with the Ref 250 and Salon2 . Using the Ref 250 for HT seems kind of wasteful in terms of tube replacement cost. I also think about keeping having two sets of amps - SS for Ht and tubes for music but swapping speaker wires between two amps is inconvenient.

I had thought of Pass labs as well but it has low input impedance and may have comparability issue as you have already experienced.

I may look at the newer Krell 400e monoblocks as well. Do let me know of your experience of the ref250 and Salon 2.

[jpgr4blu]

Hi New Guy:
As always, the best thing to do is to test listen to any prospective amp in your system. For example the 300wpc MXRs are from all accounts very liquid and beautiful amps that, according to the reviews I've read, substantially close the gap between tube and ss sound. However, many reviews have noted that the MXRs are not paragons of low end drive. That does not mean that you need more or less than 300 watts from another amp to obtain low end slam (although it's probably fair to say that you will not get it from less than 100 wpc). Many other factors come into play including impedance characteristics of the amp, preamp and speakers, current delivered by the amps, etc. Nothing like listening for yourself or talking to those who have tried the amp you are thinking about with the speakers you have.

[TOGA]

New Guy, will keep you informed, I will have more leisure time at end of Feb, now must concentrate on work. you 're right about input impedance matters. With my ARC tube pre amp, many amps that I like were become mismatched due to low input Z, such as Bryston 28B SST2, Jeff's wonderful 725 mono block. I am looking for one that has input Z of 100K-300K Ohm, such as D'Agostino Momentum, ARC's REF250/750, Krell EVO600e.
If I buy Ref 250, I will keep Moon W7M for movie or some kinds of music. If I buy Momentum or Ref 750, I will sell Moon. Or If I buy new speakers such as Wilsons, Rockport 's, then 250 Watt from REF250 will sure be fine.
Now time to go back to concentrate on what I really have to do. Good luck.

[New guy]

I went ahead and ordered the Ref 250 as well as a Krell Evolution 403e. My plan is to use the REF 250 for two channel music and the 403e for HT. By next week, my room will be filled with 7 amps - 5 Krell amps and 2 ref 250s.

[chessman]

Originally Posted by New guy

I went ahead and ordered the Ref 250 as well as a Krell Evolution 403e. My plan is to use the REF 250 for two channel music and the 403e for HT. By next week, my room will be filled with 7 amps - 5 Krell amps and 2 ref 250s.

It is a burden, but someone has to do it.

Seriously, congrats on some awesome gear.