Why is an XA30.5 a bad match for Revel Ultima Salon II speakers?

Bombaywalla,

How do you think my ARC Ref 150 SE tube amp would fare with the Ultima Salons?

My amp has 4, 8 and 16 ohm output taps. I surmise that the 4 ohm taps would work best with the Salons given its lowish impedance in the low frequencies. I seem to recall that the output impedance off the 4 ohm taps is about a half an ohm. Rated power off the 4 ohm tap is well north of 150 watts if driving a 4 ohm load.

Reason for question: I’ve had Salons on my radar screen for a while.

Bifwynne,
good to see you are still lurking around these forums - haven’t heard much from you since you installed DEQX in your system.... :-)

well, we have discussed your ARC 150W/ch amp many times in these forums. I remember that it has a pretty stiff power supply (I seem to remember 1000+ Joules) & being a tube amp it’s going to maintain its output wattage more or less.
What does "Rated power off the 4 ohm tap is well north of 150 watts if driving a 4 ohm load" mean? Is it 200W/ch into 4 Ohms?
I believe it will be much better than the XA30.5 driving the Salons as you will have atleast 2X the output wattage.....
.....but, man, I think you’ll need an even bigger amp to make the Salons sing. I’m thinking atleast 300W/ch (which is going to get expensive!).
You’ll get average sonics from your 150W/ch & like xti16 wrote it depends on how hard you want to drive the Salons. If you settle for less & drive it to lower average SPLs then you should be good but it you want more realistic listening levels, i think you’ll find that you will want a bigger amp.
I once had a speaker that could handle 105dB SPL peaks & it was really very good sonically but on rock & blues there were times I wished it could hit higher peaks.
You might be different - you might be happy with lower peak SPL???

I’ve a friend who has the original Salon speakers & drives it with a Gamut 200W/ch s.s. mono-block amp to a really, really, really good effect. He has a smaller room & they way that speaker pressurizes that room in the bass region is simply a treat. I’ve never heard anything like that in a long time....
Now the s.s. amps of that caliber are different - their output power jumps atleast 50% into lower impedances so I bet that he has something like 300W/ch or slightly more into 4 Ohms (which is where i was going with this in the sentences above).
Hope this helps. FWIW.

Thanks XTI16 and Bombaywalla.  Kinda' figured you would come out where you did.  It makes sense.  

No Bombaywalla, ... the amp does not double down wattage at 4 ohms.  In fact, if you checked out some reviews of the Ref 150 (not SE), you will see that the amp puts out between 150 and 165 watts if the amp is hooked up to a speaker load that matches the nominal tap value.  IOW, the amp will deliver between 150 and 165 watts if it is driving a 4 ohm nominal speaker load off the 4 ohm taps; an 8 ohm nominal speaker load off the 8 ohm taps, and so forth.  

It's really a function of how the amp is configured.  Although its output impedance is "low'ish" for a tube amp, it does not produce power like a SS "Voltage Paradigm" amp.  

I still own Paradigm S8s (v3), which are pretty decent over-performing speakers.  The rated sensitivity of the S8s is 92 db, which is considerably north of the Salons.  Hence, I can cleanly drive the S8s to ear splitting levels. 

BombaywaIla, I get the practical electrical realities you explained above.  I surmise you would respond similarly if I asked your opinion about matching up the Ref 150 to the Magnepan 3.7s, which I recall have a sensitivity in the mid-80s as well.

My bottom line is that I like my current electronic set up, ... all ARC.  And I am inclined to keep the amp.  Hence, I surmise that if I was interested in switching out my speakers, I would be well advised to consider speakers that have rated sonic sensitivities closer to my S8s than the Salons or Maggies, i.e., go high 80s or low 90s.

Thanks.

Bruce

P.S. -- My DEQX is off-line.  Although it adds a lot and mitigates a lot of room problems, in the end, I'd rather suffer the time delays caused by the high order crossovers than the artifact effects of adding an electronic device to the signal path.  I'm kinda' inclined to swap out my Ref 5 SE for the new ARC Ref 6, which is attracting rave comments. Hard to believe that the ARC electronics can be that good, but hearing will be believing.  

@bombaywalla , you wrote " [s]o, the DEQX is sidelined due your philosophy of minimizing the signal chain? nothing wrong with DEQX - just that you are a minimalist w.r.t. audio gear, right?"  

Yes, ... correct.  The DEQX solves many problems. That said, in my case, and IMO, ARC gear is very synergistic when used with other ARC components.  IOW, the whole is greater than the sum of the parts, ... if I got that right.  The DEQX detracts from the considerable ARC component synergistic effect, ... IMO.  

Btw, I checked the specs on the Revel Studio II.  Unlike its bigger brother, its sensitivity is close to 89 db.  See here: http://www.stereophile.com/content/revel-ultima-studio2-loudspeaker-measurements#xX3PQVeOHrCwDxHS.97

Notably, I used to own Paradigm S8s (version 2) which also had a rated sensitivity of 89 db.  My amp drove the S8s (version 2) to ear splitting levels.  And btw, the S8s (v2 and v3) have pretty wicked capacitive phase angles and low impedance plots in the bass region.  

Perhaps, I could get a similar loudness result with the Studios???  More importantly, I wonder if the Studios even sound better than my S8s.  So much hype and brand snobbery in our hobby.  Also, the Studios tip the scales at 140 pounds each.  The S8s are a slimmer 100 pounds each. Ouch!

You also suggested getting the next ARC amp model up the food chain. That would be the Ref 250 SE.  Too expensive; too much heat; not enough space.  

Thanks again.

I had Revel Studio 2s, and originally drove them in a fairly large room
with a ARC VSI60 and on most material, it sounded fine......but
when dynamics showed themselves, it ran out of gas quickly.......
so I can emphatically say 60 watts of tubes aren't enough into that
4ohm load, with mediocre efficiency......I then went to Pass X350.5
and never had an issue..........but I eventually swapped the Studios
for Magnepan 3.7s, which are also 4 ohm with mediocre efficiency,
and they wanted even more than the X350.5, so I went to Bryston 7BSST2s with great results 900W into 4ohm......I now still have those speakers with Bryston 28BSST2's, nearly 2KW into 4 ohm and the Maggies just sing........I would never consider Revel again against these speakers, but I liked them while I had them........