Last mile question on tube amp

Sasha · « **on:** 7 Mar 2006, 07:16 pm »

I am down to one and only tube amp I liked, out of all I had chance to hear, Korato Ikarus, reason being that it sounds very fast and dynamic, in control all the time no matter how complex music gets (no compression), but still with tube richness and without any loss of details, quite opposite to the majority of other tube gear I heard – mellow, slow sound that puts you to sleep.
Examples of some well reviewed tube amps that I did not like for the reasons above would be Prima Luna Prologue II, Cary Audio SLI-80 and MC275.
My only question at this time is if VAC Avatar is worth listening to?
Does anyone have any experience, and could describe the sound of VAC Avatar as compared to those amps I mentioned?
Where does it belong, on fast or slow end, authoritative in low end or somewhat mushy, that sort of a thing?

flintstone · « **Reply #1 on:** 7 Mar 2006, 07:40 pm »

Rogue Audio...fast and musical if you get a chance.

Dave

TheChairGuy · « **Reply #2 on:** 7 Mar 2006, 07:55 pm »

Quote from: flintstone

Rogue Audio...fast and musical if you get a chance.

Dave

I've been thinking about Rogue myself. I've not liked tube amps, in general, when I've heard them. But stellar AudioReview reviews are convincing, as is the Mark's committment to great service.

I, like Sasha, have found them to be slow, pillowy, and induce drowsiness. But Rogue, among relatively affordable amps, seem to have converted even steadfast SS amp guys into tube amp lovers.

Sasha · « **Reply #3 on:** 7 Mar 2006, 08:22 pm »

This may be just my driveling, but I find Rogue design somewhat strange.
All their amps seem to specify quite high power considering the type and number of tubes used.
For example, for M-150 monoblock they claim 150W but use only 4 KT-88 tubes.
Does this not indicate that they are driving those tubes too hard?
Compared to a typical application of KT-88, you usually see 20W per tube, rarely 25W per tube, while with Rogue it is in this example 37.5W?

R_burke · « **Reply #4 on:** 7 Mar 2006, 10:46 pm »

Quote from: Sasha

Compared to a typical application of KT-88, you usually see 20W per tube, rarely 25W per tube, while with Rogue it is in this example 37.5W?

My Sonic Frontiers Power 2 gets 110W out of 4 KT88s (27.5) and I was always curious how Rogue got so much more, but figured it was a matter of specmanship (upper limits vs RMS???, or something like that)

spectralman · « **Reply #5 on:** 8 Mar 2006, 01:29 am »

If you think tube amps are slow, pillowy, and sleep-inducing, you haven't heard any Atma-Sphere OTL's. They are anything but!!! Fast, dynamic, very good bass. Unfortunately, expensive and they produce alot of heat. To my ears, the trade-offs are worth it.

Bill

flintstone · « **Reply #6 on:** 8 Mar 2006, 01:53 am »

Well my Rogue 120 Magnums drive my 4ohm fullrange Apogee Duetta Signatures without a hitch...replaced a Krell Kav-500.

I still have a Krell Ksa-250 that I was going to switch back and fourth with every now and then...I've never wanted to yet.

The Rogues are not classic tube sound...I would never go there with a pair of fullrange Apogees.

There are tons of good tube amps out there...the Rogues are just some of them.

Dave

mihilli · « **Reply #7 on:** 8 Mar 2006, 02:07 am »

Quote from: Sasha

I am down to one and only tube amp I liked, out of all I had chance to hear, Korato Ikarus, reason being that it sounds very fast and dynamic, in control all the time no matter how complex music gets (no compression), but still with tube richness and without any loss of details, quite opposite to the majority of other tube gear I heard – mellow, slow sound that puts you to sleep.
Examples of some well reviewed tube amps that I did not like for the reasons above would be Prima Luna Prologue II, Cary Audio S ...

You should check out Manley amps

Roger A. Modjeski · « **Reply #8 on:** 8 Mar 2006, 07:28 am »

Hi,

There are published application for 100 watts per pair of KT-88 or 6550. I use an extension of this application in the Music Reference RM-200. It requires a B+ around 650 Volts rather than the more typical 450. The screen grids are run lower, well within their safe region. You can see the amp at www.ramlabs-musicreference.com along with the RM-10 that gets 35 watts out of a pair of EL-84/6BQ5. That one uses an unpublished application I wrote myself.

I can't speak for Rogue, but you can run the RM-200 at any power level and not exceed dissipation limits of the tube. BTW. Dissipation is usually what limits power and nothing else.

Roger A Modjeski

lonewolfny42 · « **Reply #9 on:** 8 Mar 2006, 07:43 am »

Some good deals on Audiogon.....VAC Avatar....and Rogue 120 Mono's.....worth a look.

drphoto · « **Reply #10 on:** 9 Mar 2006, 12:43 am »

An Audio Research amp I heard (110/w/ch...a VT-130, I think) was very tight and fast, so much so that it's owner went to a modded Dyna ST70 because he likes that syrupy old school tube sound.

He'd sell that ARC cheap if you're interested.

Sasha · « **Reply #11 on:** 9 Mar 2006, 09:17 pm »

Well, considering it is nearly impossible to have a meaningful audition of all these amps suggested, and the fact that I had no objections to the sound of Korato, I decided to purchase it.
Expensive little piece, but compared to others I had chance to listen to, way above.

skrivis · « **Reply #12 on:** 9 Mar 2006, 10:02 pm »

Quote from: drphoto

An Audio Research amp I heard (110/w/ch...a VT-130, I think) was very tight and fast, so much so that it's owner went to a modded Dyna ST70 because he likes that syrupy old school tube sound.

He'd sell that ARC cheap if you're interested.

"Fast" amps? As in slew rate?

If an amp can reproduce the highest frequency of interest, isn't it fast enough?

miklorsmith · « **Reply #13 on:** 9 Mar 2006, 10:27 pm »

Fast as in transient behavior. Some tube amps are notably slow. The 300B amps I just sold are of such species. It was obvious, as the front array of my Definitions didn't seem to be integrated with the rear. With the Clari-T powering the fronts, there is no disconnect.

Hogg · « **Reply #14 on:** 10 Mar 2006, 02:24 am »

Quote from: Sasha

Well, considering it is nearly impossible to have a meaningful audition of all these amps suggested, and the fact that I had no objections to the sound of Korato, I decided to purchase it.
Expensive little piece, but compared to others I had chance to listen to, way above.

Sasha, congratulations on purchasing the Korato. What's the rest of your system?

Jim

Sasha · « **Reply #15 on:** 10 Mar 2006, 05:03 pm »

The rest of system is Rotel CD player 1072 going digital into external Musical Fidelity X-DAC V3 with X-PSU power, then into the Korato.
Speakers are yet to arrive, it will be a pair of PMC FB1+.
I also have Squeeze Box 3 with digital connection into MF X-DAC so that I have two transports, one being mentioned CD player and one being PC with network connection to SB3.
There is also Yamaha universal DVD player DVDS-2500 that does DVD-A and SACD, connected directly to Korato but that is nowhere near the sound quality of other sources.
Interconnects are Audio Quest DiamondBack and speaker wire is Linn.

hmen · « **Reply #16 on:** 10 Mar 2006, 08:16 pm »

I have to agree with Spectralman. My Atma-Sphere M60's are exceptionally fast and tight. A pair just went up on Audiogon yesterday.

http://cls.audiogon.com/cgi-bin/cls.pl?ampstube&1147120368

Hogg · « **Reply #17 on:** 11 Mar 2006, 02:10 am »

Quote from: Sasha

The rest of system is Rotel CD player 1072 going digital into external Musical Fidelity X-DAC V3 with X-PSU power, then into the Korato.
Speakers are yet to arrive, it will be a pair of PMC FB1+.
I also have Squeeze Box 3 with digital connection into MF X-DAC so that I have two transports, one being mentioned CD player and one being PC with network connection to SB3.
There is also Yamaha universal DVD player DVDS-2500 that does DVD-A and SACD, connected directly to Korato but that is nowhere near the sou ...

Sasha,
Interesting system. I'll be interested in learning how the Koarto drives the PMC speakers.

Jim

Bill Baker · « **Reply #18 on:** 11 Mar 2006, 02:33 am »

Not too long ago, I had a Sonic Frontiers Power 1 (I think) come through on a trade. I found this amp to be very fast and dynamic with a very neutral presentation. They can be had used for a reasonable price also.

Just another option thrown atchya.

Sasha · « **Reply #19 on:** 11 Mar 2006, 04:56 pm »

Hogg,

I auditioned the entire system with PMC FB1 (older version, could not find FB1+ to audition), and there were no issues with power, FB1/FB1+ is efficient enough for Korato, if that is what you are referring to.
FB1+ is the same speaker with upgraded tweeter, crossover, and TL foam.