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Need Help on Tube Rolling for VAC Avatar

Just bought my very first tube amp (integrated), VAC Avatar, a couple months ago and it has been great. Pairing with the Sonus Faber Grand Piano speakers and Rega Planet 2000 CD player, with Nordost Blue Heaven IC and bi-wired speaker cables, I'm quite happy with the current set up.

HOWEVER, like any other self respected 'goner here, I just can't stay status quo and am contemplating of experiment tube rolling, with hopes to explore even better sound (I know it gets very personal here). The problem is...I don't know where and how to start and would like to get some advice from you guys.

First off, here are the 3 sets of stock tubes (Chinese) that I have in the amp:
- 12AX7 x 2 (line stage)
- 12AU7 x 3 (power amp)
- EL34 x 4 (power amp)

Newbie Questions:
- for the most bang for the buck, which set should I try rolling first?
- any suggestions as to what brand gives you what type of sound relative to others? (e.g. Mullard gives you a lush sound and much warmer relative to RCA clear top?!?)
- before I have to spend the money that I don't have, what is considered "entry level" tubes good for experimenting?
- comments on the following brands: Mullard, Telefunken, RCA, Svetlana, Sylvian, Svotek, etc.
- what's a good and reliable place to buy tubes? Used? NOS?
- perspective on Chinese vs. Russian tubes?

As you can tell, I have no clue where and how to start but would love to learn more. That said, the last thing I want to do is to spend hundreds of $ and get nothing accomplished. Any advice is greatly appreciated. Thanks in advance, guys.

Steve
stevenkc
stevenkc OP
49 posts
 
Ta ta ta...Almost a month after my initial Newbie Tube Rolling posting here, here is the verdict of my 1st experiment:

I've decided to use the JJ 12AX7's for the input stage, and keep the stock (Chinese Golden Dragon?!?) EL34 tubes for the power amp.

As I mentioned from my earlier posting here, I've got myself a set of Electro Harmonix (EH) 12AX7 and EL34. The switch made my system a lot darker and for some reason, the soundstage also closed in a bit and moved to the back. Bass bot extension, but boomy, and overall presentation got dull. As you can see from my gear, they are already leaning more toward the warmer side of things and adding the EH's just makes the system a little too warm and dark for my taste.

Matching the JJ's and the stock EL34's brought everything back: clearer and more refined detail without the brightness, the wider and mid-to-frong soundstage, lush mid-range, and overall balanced presentation. Only thing that could be improved would be the bass department. It's tight, but doesn't have great extension.

Problem solved as I tried my 1st after market power cord. I was pretty skeptical in the beginning, but boy, it really opened up (even more) the soundstage, give (even more) clarity to the overall presentation, and more importantly, a quick and tight bass.

Now that I seem to have found what I've been looking for, but still curious about the great things that I've read on both Svetlana and JJ Tesla EL34's. Anyone has experience with these two sets?
ladderlake's avatar
ladderlake
21 posts
 
Hi Steven,

I know the Svetlana EL34's are a good tube from personal experience and comments from Audiogon and AudioAsylum.

Amazing how different tubes will 'tune' the equipment, good for audio junkies -- gives one something besides cables to play with.

I'm using Telefunken smooth plates for 12AX7's and mullards for the AU7's. Very happy with the sound on some GMA Europas.

Cheers,
Karl
tlh28
90 posts
 
Hi,

I'm an Avatar owner as well; love my amp. I've tried tube rolling with newer Mullard 12ax7s/12au7s from Upscale, older Mullards from VTS, some JJs from a local shop, and some NOS RCAs. Probably spent close to the cost of an SE upgrade on tubes. I kept coming back to the stock tubes. The stock tubes are Kevin's select Golden Dragons. Kevin spends a lot of time voicing his amps, and I suspect that the tubes he has selected are going to come closest to the sound he is trying to achieve. I just couldn't find any other tube that had the same airy highs, liquid but clear mids and deep bass. I also tried some older Mullard EL34s (very expensive), and ended up selling them as well. Perhaps some of the NOS Teles or Bugle Boys, or the premium JJs or EHs might provide an improvement? Some VAC owners also say that a NOS French tube, Radiotechnique (?), works well with VAC equipment (heard this from another Avatar owner locally), but haven't heard the tube myself. If I were to experiment any further myself, I would want to try either the Tele or RTC 12au7s/12ax7s. Not sure I would experiment with the EL34s. Please keep us posted if you try any other tubes. Thanks,

Terry
stevenkc OP
49 posts
 
Thanks guys for the additional input to keep this thread "active". Lately, I've heard about JJ's "blue" version of the EL34, and was told that it can provide better bass extension.

Does anyone have any experience with the blue JJ's EL34? Is the additional cost (approx. double of "regular" version) worth the investment? Any feedback would be greatly appreciated.

Steve
tlh28
90 posts
 
Steve,

Can you tell us what power cord you are using, and what improvements it made? BTW, I found that even the cheap JJ 12ax7s I purchased were better than the NOS tubes I tried. All the NOS tubes sounded as you described the EH EL34s- too warm and mushy sounding. The JJ's had a little more dynamic sound than the stock tubes, but I thought sacrificed a little airy-ness, were slightly less three- diminsional than the stock tubes. Do you know which version of the JJ's you picked up? Thanks again,

Terry
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