Ayre V-Kxe and Thiel 2.4s


Anyone heard this combo?

I've been waiting for an appropriately priced Pass Labs 250.5 to pop up, but the wait has made me consider some other alternatives. In my conversations with Pass, they've steered me away from lower power options (e.g., the 150.5), so I'm concerned that the V-Kxe won't have enough power to really push the Thiels. However in reading over the positive Stereophile review of the 2.4s, I think much of the listening was done on the this amp. It does save me quite a bit of cash over the Pass 250.5 though.

Any opinions are welcome (along with other amp suggestions). Thanks folks.
cal3713

Showing 22 responses by unsound

Stevecham, with all due respect, he's already unsatisfied with much more power than your currently running with Thiel 2.4's. IMO, it might be enough, then again it might not. Depends the room, and the expectations.
Cal3713, may we ask how much do you comfortably want to spend on amplification?
Here is Stereophile's measurements of the the Thiel CS 2.4s:
http://www.stereophile.com/content/thiel-cs24-loudspeaker-measurements
I think it fair to say, that it doesn't appear to be that easy a load for a typical low powered tube amp.
Based upon some comments posted here on Audiogon, the cost of refurbishing Krells can be quite expensive, with that it mind, it might be best not to purchase anything too old, unless it has documented proof of already being appropriately refurbished.
Stevecahm, I've heard an older similarly powered cj tube amp running older 2 series Thiels that were a much, much easier load, and while it could make sounds, those Thiels never could produce all they were capable of with that amplification.
With all due repect, and despite the included commentary in those test results, those measurements aren't exactly impressive; clipped at 36W (15.6dBW) ("isn't bad", really ?), and well below Thiels recommendation. If anything, perhaps it's the power supply and output trannies that make this amp perform so poorly on the bench?
Charles1dad, I can't and won't discount Stevecham's listening experience, but he's the one that first provided measurements to support his position. I respect that he also offered this objective argument to his position. After all, without it; it all just becomes unsubstantiated opinion. That is not to say that subjective opinion is not without merit, and that includes his as well. Bear in mind, that I also offered similar subjective opinion with similar, if not quite identical gear. Furthermore, the OP's experience has suggested that under-powering these particular speakers was less than satisfactory. FWIW, based upon the posts here on Audiogon most seem to agree with Thiel, the OP, the usual technical arguments and my experience too, rather than Stevecham's.. If Stevecham is happy with his rig, power to him, but the OP is seeking advice and I opt to provide mine too. Speaking of which, what are you providing?
Charles1dad, the last line of my last post was uncalled for. Please accept my apologies.
Russellrcncom, the placement of the volume knob might not be meaningful with re: to the respective differences between power output of the different amplifiers. The amplifiers just might have different input sensitivities for full power output, and your preamps might be providing that much or more or less than that much output at a given setting to drive your amplifier to full or near full output at less than the preamps full output. For example: one amp might need 2 volts to achieve full power output, the other amp might need 2.2 volts to achieve full power output to achieve full power output, while your pre amplifier might be able to put out up to 7 volts at it's maximum setting, and up to 2 volts at it's 8 o'clock setting.
Charles1dad, we don't know of Steve's great sonic results, only of his opinion of such. Thiel recommends more power, Pass recommends more power, and there hasn't been anything but an anecdotal reason to suggest otherwise. The measurements provided by Steve don't seem to suggest that the c-j or something very similar, would be as good, never mind better than what the OP has already tried. I would think that the point OP started this thread was to expedite the process of selecting the appropriate amp for his needs. With that in mind, I think it fair to point out that the c-j or something very similar, for the reasons I've already posted, is not as likely to satisfy the OP to that end as much as some other alternatives.
Cal3713, I was just responding to your thoughts of adding an independent 20 amp line for your amp.
Countingbackwards, the XA30.5's the OP was using is a pretty modern design. Moving up to a more powerful XA.5 would probably be ideal, but there are budget considerations.
I know this is somewhat arbitrary, but I think a system with high end aspirations should be capable of 100 dB peaks.
Charles1dad, my post was a direct response to a question Stevecham asked in the previous posts. The ability to reach a certain volume level is no way the only, or the most important criterion. One can listen to such volume levels with some frequency, so long as the duration is not too long, without fear of hearing damage. Greater volume levels happen quite often during some live unamplified live musical performances. In that most of us listen in very different environments than live venues, not achieving actual potential live volume levels is probably not called for most us, but a reasonable proximity is not too much to ask for.
Stevecham, I suspect that with the Thiel CS 2.4's set up as the Thiel recommends, that at 100 dB the conrad-johnson CAV50 would be well into clipping.
Stevecham, the Thiel 2.4's don't measure at 88 dB 1 Watt at 1 meter. They measure 88 dB 2.83V at 1 meter.
If my understanding is correct(?), if you take into the consideration the actual impedance of the speakers, you'll find that Thiel 2.4's are actually closer to a nominal 83 dB 1 Watt at 1 meter.

http://www.stereophile.com/content/thiel-cs24-loudspeaker-measurements

The 77 Watts wpc into 4 Ohms is what the cj CAV50 can do when only driving one channel. When driving both channels at 1 kHz the power drops to 40 wpc. It's interesting that the power output seems to go up into 20 Hz (a moot point, as that's below the Thiel CS 2.4's capabilities) and also go up at 20 KHz (which the Thiel CS 2.4's are capable of) for those that can hear that high up.

http://www.stereophile.com/content/conrad-johnson-cav50-integrated-amplifier-measurements

Keep in mind that the Thiel CS 2.4's do have a rather challenging phase angle too. Not something that most low powered tube amps tend to appreciate.
Thanks for the update. I'm not at all surprised that the combination of the 30 and Thiel subs provided the most satisfaction. Enjoy!