Head-Fi.org › Forums › Equipment Forums › Headphone Amps (full-size) › First Impressions: RKV tuberolling
New Posts  All Forums:Forum Nav:

First Impressions: RKV tuberolling - Page 2

post #16 of 21
2/14/03 at 4:47am
Hirsch: Thanks for the info on the RKV...

I guess it always comes down to ... "you get what you pay for". Buy the $1000, or more, RKV and you don't have to roll tubes.
Buy the $350 MG Head and roll away....

I guess that which you buy, depends upon your audio intent and your wallet thickness...

Sadly... my last RKV Mk2 quote from my closest dealer was... DOH... $1295...

Hell, for that price, I can get a full blown tubed preamp with headphone amp for less than that...

Whoever AudioValve is using as dealers here in the USA, they are getting screwed!

As much as I'd like one of these... I'll never own one of them.

Heck Hirsch... even your MicroZotl plus my HD600 headphones recently sold for only $850... ?
How the heck can the RKWreck sell for almost double the ZOTL price???
Reply
post #17 of 21
2/14/03 at 5:01am
Thread Starter 
Chalk my initial impressions as psychoacoustic. I switched back to the stock Polamp tubes and heard exactly the same things I heard using the Teles. It seems like I was listening much more critically to my music when I first dropped the Teles in, and then when I switched back to the Polamps they totally negated my initial thoughts. The same details were there, and at the same levels. At least I know that when in doubt, and before posting, I should verify what I'm hearing against another set of tubes. Sorry about that.

Seems that Helmut is on to something here with his design. Either that or all the PCL805 tubes are indeed identical, from the same plant, and just have different names plastered on them. I can't tell anything different between the Tele and Polamp tubes AT ALL. With other tubes there was always something slightly different in the internal structure between manufacturers, but not here. I also find that the Tele tubes rarely have the diamond imprint on the bottom of the tubes. Out of the 8 I have only 1 has a diamond on it. So, either 7 are fakes, or all or real, I can't tell. It seems like a good time to examine the inner working of these tubes a little closer to see if there are any differences.


Hirsch, I hadn't heard that you got an RKV. Congrats! I just love this thing. Now that you got one, you gonna do some more evaluating of it against the ZOTL with different headphones? Enquiring minds want to know.
Reply
post #18 of 21
2/14/03 at 5:14am
Quote:
Originally posted by ServinginEcuador
Enquiring minds want to know.
Yep.. ME! If they're somewhat similar.. I could save a few hundred bucks getting a ZOTL over an RKV... but at this point, I can't even get rid of my Cosmic
Reply
post #19 of 21
2/14/03 at 6:14am
Quote:
Originally posted by Hirsch
Helmut Becker of AudioValve read this thread, and sent me an e-mail. He doesn't feel his English is good enough to post publicly, so I'll try and relate the concepts, and hope I get them across intelligibly.

The reason that changing tubes makes an audible difference is the operating characteristics of the tubes (the curves). These can vary depending on the brand of tube, the age of the tube, etc. Most tube amp designers do not do enough to stabilize the tube. By having circuitry in the amplifier that controls the operation of the tube, the tube's operating characteristics become relatively unimportant, and tube changes will not cause significant differences in the sound. It is very important to use the components needed to create a stabilizing circuit for the tubes, or the sound of the amplifier will change any time a tube changes. Leaving the sound up to the random choice of tube is bad in a high-end audio product. The RKV uses a DC-coupled servo regulator circuit that minimizes the influence of the operating characteristics of the tubes on the sound. This makes the amp sonically stable using the same tubes for very long periods of time without losing any musical quality, as well as making the RKV very resistant to sonic change produced by rolling tubes.

So, Mr. Becker has very deliberately designed the RKV to be resistant to tuberolling. It should have pretty much the same sound regardless of brand of tube used. I'm still going to try one or two other brands, just to see for myself how resistant to tubrerolling the RKV really is...
VERY interesting piece of info straight from the horse's mouth. It agrees with my experience, when trying to tube roll the RKV with different tubes (not NOS, just a cheap quad I actually bought as a backup), the sound didn't budge. Certainly different from when I tube rolled one of the earlier MG Heads, where every single tube I swapped in made at least *some* audible changes.
Reply
post #20 of 21
2/14/03 at 10:32am
Quote:
Originally posted by merc


Whoever AudioValve is using as dealers here in the USA, they are getting screwed!
The best way I know to get one is through Meier Audio. The price has risen lately, due to the dollar weakening against the Euro, but is still well under what you were quoted.
Reply
post #21 of 21
2/14/03 at 1:57pm
hirsch, i'm looking forward to what you find. the rolled off treble on the rkv has begun to get to me and i'd really like to see if i could get a better high-end with some different tubes.


in other news, 1500 posts !
Reply
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Headphone Amps (full-size)
Head-Fi.org › Forums › Equipment Forums › Headphone Amps (full-size) › First Impressions: RKV tuberolling