Best Tube Amp For Sonus Faber? Or Pass XA-100.5? $6-7,500 Budget, Purchasing Used.

Also, how much heat do the 100.5's generate? I listened to some larger Pass mono's recently, and they turned a huge listening room into a sauna within an hour!

I was hoping I might hear from you, as you and I have shared some attachments to amplifiers, going way back to the Jeff Rowland Model 6's. You've also had quite a few other very good amplifiers, as I recall. 

Your comments on the 100.5's carry a lot of weight, for that reason. It sounds as though you are truly satisfied with them, the midrange, the treble, etc. vs your old tube amps?

I also need to avoid any fully balanced power amplifiers, as my system is single ended.

JC

Thanks very much for all the input, guys. Like jmcgrogan2, George and kdude66 , I am more and more of the thinking that a solid state amp is probably the way to go with these speakers. I've just been a tube guy for so long. However, great performance is great performance, no matter how one gets it.

The 100.5's have been recommended previously by at least half a dozen audio people who I truly respect, including a couple major audio reviewers that I discussed it with at Axpona. Now the question is waiting for some to appear for sale. I have been on the waiting list at Reno HiFi  quite a while for a pair of 100.5's. Lets hope that Mark is able to come through with some sooner than later. 

jmcgrogan2,

I noticed the same thing about Reno Hi Fi's used inventory significantly dropping off over the past year too. Doesn't give me a good feeling about Mark being able to come up with a pair of 100.5's for me, and they don't show up anywhere else much either. Also, knowing that the Reno team has gone over them, and re-warranties them is very nice to know.

Before you consider moving to the .8 series, make sure you do some serious listening to them. I've auditioned the 60.8's, the 100.8's and a couple higher power models in the series. There is no question that they are more emphatic and demonstrative in their sound than the .5's, and also offer greater bass control and solidity. However, they do not offer any of the midrange warmth, treble smoothness and comfortable musicality of the .5's. For brief periods, the .8 series is extremely impressive, but not a sound I would want to listen to extensively. Just IMO.

jperry,

After reading the earlier suggestion, and some additional reviews, I did list the Aesthetix Atlas for serious consideration, going forward. I also checked out the one being offered right now on Audiogon. If it were only silver (the same as all the rest of my components) I might have already snapped it up for that price!

nkonor,

You’re results with that combination sound ideal, but isn’t the Manley Steelhead just a phono stage?

Wharfy, you said "I would pair Audio Research with Sonus Faber since both are owned by the Fine Sounds group AND ARC is now using Sonus Faber to voice their equipment."

Interesting timing. I have a very good friend, and audiophile, who spent much of last December auditioning speakers with me three or four times a week before I settled on the Sonus Faber Olympica III's. I just got a call from him on this very topic. He is currently in Chicago on business and ended up with yesterday afternoon off due to a client cancelling a meeting. He took the time to explore a few audio stores. One of them was a Sonus Faber dealer and had the Olympica III's on display powered by the Audio Research REF-75 power amplifier and an Audio Research preamp (he does not recall the model). He says it powered the Olympica III's really well, produced excellent sound and he apparently listened for an extended period.

I have always loved the look of that amp, and had respect for AR. It would seem that might be one of the only tube amps that seem able to handle the load of the Olympica III's. I know it is a fully balanced design, so it would require me selling my existing preamp and likely buying an AR model (maybe I could find a REF5 at a good price), but that would certainly be an option. 

Chumsusi, thanks for the Line Magnetic  219ia recommendation. Obviously we "were" thinking alike. However, that's my amp for sale. Just purchased it ten days ago. Wonderful sound, but it simply can't drive the Olympica III's well enough. :(

jmcgrogan2, I saw that same listing for the 160.5's, and that's an amazing price for those. I would jump all over that, but also just read the Tone Audio review by Jeff Dorgay, who knows his stuff. He clearly said that the 160.5's needed a balanced preamp to perform optimally, and my preamp is single ended. I "believe" the 100.5's will work effectively with a single ended pre?

Timing, it would appear, is everything. The additional $1000.00, plus what it would cost to ship those 130 pound beasts (x2) nearly across the country has essentially taken out them out of my budget :(

He has also changed the ad to reflect that they are only available for one day........

I should perhaps have mentioned that a big part of originally wanting thr 100.5's had to do with how impressed I was after hearing the 60.5's (not enough power for my speakers) and recalling John Atkinson's review a couple years back calling those the best amplifiers he had ever heard. As a followup, I was told that the 100.5's were essentially the 60.5's upscaled, which doesn't seem to be the case?

At the point of making a final decision now. In rereading this discussion, I was struck by jmcgrogan's early comment that 
 
"I tend to agree with George, I'm not sure that a tube amp would work well with the Sonus Faber Olympica III's, they are not an easy load.

Any VAC amp that can put out 100 wpc and use KT-150 tubes though MAY be able to do it.

I was actually using a VAC 160iSE integrated amp before the XA-100.5 mono-blocks, and my speakers have similar specs (90 dB, 5 ohm versus your 90 dB, 4 ohm).

Switching to the XA-100.5 amps, the sound-stage opened up immensely. Not really surprising going from a tube stereo amp to SS mono-block amps.
Mating the Pass amps with an ARC Ref 5 preamp, the resolution of the highs and lows also became more extended and defined.

The only place I would give the edge to the VAC was in the midrange.
Though the Pass are quite warm and musical, the VAC had that touch of *magic* in the midrange, that fuzz on the peach quality, that only a tube amp can do."

I would suspect the sound from the upper level PHI power amp would improve over the VAC integrated that you had, possibly not in a huge leap, though. And it sounds like your satisfaction was clearly greater with the the Pass 100.5's, excepting the extra touch of tube magic in the midrange.

Going into this, I had really been leaning toward the 100.5's, and as I noted before, had been on a waiting list for a pair at Reno HiFi for the past year. I love the look of those amps, and would have bought an available pair (had one shown up) except for the fact that someone whose knowledge I truly trust, and who has owned and enjoyed about half the Pass line of power amps said they were his least favorite because the bass was puffy and inadequate. 

djfst said:

" The new IQ continuous auto bias in the latest VAC amps are a night and day difference from their prior 160, 200, 300 phi models.  Far more smoother and transparent, tighter bass, etc and more stable power output makes it a lot easier to handle all speakers.  I owned the VAC and as well as the SF Olympicas and the Elipsa and handled them fine.  the VACs are paired with Magicos, Focals, Vandersteens, Sonus Fabers, Harbeths, and know they can drive them well, even with the stock KT88s.   But if you're in love with the PASS LABS, then you it seems like you found what the sound you're after."

The problem I'm having in moving to a Pass is size and heat. That and the fact that as joeinid noted above, the next amp up the line that shares the true greatness of the 60.5's that I like so much are the 160.5's. Those are not only huge, but can each double as a furnace, in my room, I could sell space as a sauna. Not to mention they are thousands out of my budget. 

I was considering the highly rate Pass 350.8, and one was just available at a price several thousand under the going rate, and in my budget, but it sold before I could make a final decision.

So I was strongly leaning back toward the VAC and even talked to them at length. I know the PHI 300.1 will handle my speakers perfectlY, and there is one available, but it's not the latest series which you've noted represent a "night and day difference". And the newer model PHI 300.1a, on the very rare occasion it is available for sale, used, runs in the $10k area and also out of my budget. 

Those situations currently have me in a position where there isn't a clear choice unless I go with the PHI 300.1 available at the moment, which, both you, and an audiophile friend from Chicago have advised me is decidedly lower in sound quality than the newer version. 

I'm a tube guy too, and so, share your thoughts on this. When I talked to VAC, they were pretty clear that they thought even the older PHI 300.1 would outperform the standard 200IQ. Which it should, granted that the list on the PHI 300.1i, when last available a few years back was $20k, vs $14k for the 200IQ. And the PHI 300 are the top series, in terms of performance. They also had some concerns that the 200IQ stereo version would not prove sufficient to optimally drive my speakers fully. 100wpc is somewhat marginal. I also can't bear to have tubes locked up in a box, I need to see them! Not sure why they went that way with the 200IQ's.

They did say the the Signature 200 IQ Monoblocks would certainly better the PHI 300.1, and also drive my speakers to perfection, but those are $28k new and, even used, would not come near a price I could afford.  

djfst,

Thanks VERY much for your continuing help and information. I actually talked to Brent, as Kevin wasn't available, but I understand it, he is Kevin's right hand man. and he was incredibly helpful and knowledgeable. We discussed a lot if things, but I "believe" it was the current model PHI 300.1a which, and again, IF I understood him correctly, would still outperform the 200IQ. And again, that makes rational sense as I have trouble imagining that they are selling a $14k amp that outperforms a $20k amp in their current lineup? But I need to validate that I have all these facts right and will talk to VAC again on Monday. I will report back here and qualify too.

I know that any other amp I am aware of with 100wpc would not be a match I would trust with the load of the Olympica III's, given it's overall difficulty to drive, and it's drops to 2 ohms. Granted I am likely a bit oversensitive on that topic, since I've just had to resell an amp at a loss, that I truly wanted, and had just purchased two weeks ago, but which could not drive the speakers. That despite a major review telling me I would have no issue. 

I will very specifically revisit that when I talk to them on Monday. 

Lastly, thanks for that link. Clearly great minds think alike, as I only just finished reading that entire discussion after looking for more info on the 200IQ's earlier. It's very impressive commentary, though, granted, they are talking about using a pair of the amps as monoblocks. 

djfst,

Quite a bit earlier in this discussion you said "  Would not go with the VAC Phi 300.1.   Definitely go with the updated VAC Signature 200 IQ with continuous auto bias.  100+ watts and has all the bass and tightness of solid state and the midrange is fantastic.    Retails for $14k but there is a like new one listed on US Audiomart.  With the auto bias of the 200 IQ, you can plug in any KT88, KT120 or KT150 and change out the 6sn7 driver tubes if you want to tailor the sound.  It is so user friendly and the stock tubes are wonderful though.  Have owned both the Sonus Faber Olympica III and the Elipsa SE.  The VAC controls the bass of the olympica which can often sound a little bloated if not having a high quality amp."

Which VAC amp were you referencing as handling the Olympica III and Elipsa so well? I originally thought you were referring to a previous amplifier, not the Signature 200IQ. If it was the Signature 200IQ stereo version, that would carry a lot of weight towards my decision. 

Thanks for the tip on the 8 ohm taps. I would not have expected that. Another reason why it's good to experiment on what might work best. By the way, what preamp were you using with the Olympica III's and the 200IQ?

Very eager to call VAC tomorrow to get clarification, and answers to some key questions. After that, I think I will know where I stand, and what to do. 

djfst,

My current preamplifier is the top of the line PrimaLuna Dialogue Premium, which I have loaded up with very good NOS tubes. I find it to be a giant killer under $10k (granted I stole that line from Kevin Deal who may be  a bit biased, but the reviews support it). 

My list of dream preamps would include the Joule Electra LA-300ME and LA-150-SE, the Conrad Johnson ART 2, the Zesto, and something from VAC. 

I've read great things about the Herron, but have never auditioned one or otherwise had experience with that preamp. What can you tell me about it?

djfst,

Are you a member on any audio forum where I could PM you, I have made a decision after a long call with VAC today. Some of what was said is not information I feel it right to share here, as it was a private, and extremely upfront conversation. 

For everyone else, I'll report back here with what choice I made, assuming my offer is accepted, etc. 

06-19-2017 3:32pmnightfall said...
"My current preamplifier is the top of the line PrimaLuna Dialogue Premium, which I have loaded up with very good NOS tubes. I find it to be a giant killer under $10k"


aolmrd1241 said
I concur. What NOS tubes are you running?

These for the 5AR4’s:

https://www.upscaleaudio.com/collections/vacuum-tubes/products/philips-5r4gys-made-in-holland

CBS 5814A for the two critical positions, RCA NOS, 1950’s for the four other 12au7’s.

I discovered how you can PM here. Thanks. PM's sent.

To everyone else, thanks for all of your valuable and insightful information, it has all been helpful in my arriving at a final decision on what is an extremely important purchase for me.

In the end, due to its far newer design, Sentry circuit, Continuous Automatic Bias Adjustment, overall reliability, and it VAC heritage of sound, I have made an offer, and will be purchasing a VAC Signature 200IQ. 

jmcgrogan2 said:06-19-2017 8:09pm

Are you a member on any audio forum where I could PM you

You can PM members on Audiogon.

If I had known that, I would have PM'ed you previously! Now if I could just find the way to do that.

abrew19,

I was told by people involved with the company that the 60.5's would not be a good match due to the requirements of my Sonus Faber Olympica III's. They are 4 ohms, are rated at 90DB sensitivity (which I think is definitely inflated) and drop down to 2 ohms at times. I tried a very good pair of tube monoblocks capable of 65 wpc and they were not sufficient. 

If the 60.5's seem likely to power your speakers, I would re-read the Stereophile review of them, where John Atkinson called them the finest amps he has ever auditioned. 

I have been to Houston a number of times for work, and I would be concerned about the heat output of the 100.5's too!

JC