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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

Showing 4 responses by stevenkc

stevenkc OP
49 posts
 
Thank you so much for all your input. I've taken all your feedback and did a lot of reading in the past week. Man, you guys are right, some of the suggestions are not cheap, especially with a matched quad. As a newbie, I just ordered a match quad of Electro-Harmonix EL34 and a pair of 12AX7 of the same brand for experimental purpose. Just thought I would give it a college try and see what comes out of it without putting a big hole in my wallet. I'll let you guys know my 2 cents as soon as I plug/break them in, and try the pre-amp/amp both independently and seperately. Funny I've a feeling that I'm going to get hooked. Stay tuned... :-)

P.S. I really appreciate everybody's input. What a helpful group. To answer some of your questions...

Philjolet:
I love the Avatar and very happy with its performance as you can see from this thread that I'm not alone. Never regrad that I spent the extra money. I'm hoping to be able to keep this amp for a while.

Jax2 and Elevick:
Thanks a lot for your insight and tips. I really appreciate your help and I've learned a lot.

Steve
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?
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
stevenkc OP
49 posts
 
Terry,

Still using the stock power cord. I bought a Synergistic A/C decoupler pc here for my Rega Planet 2000 cdp and have been very pleased with the result - more airy, and more spacing between instruments. Given limited budget, I was just trying to get the most out of the money at the time with the old saying of "cleaning the source first: source to pre-amp to amp to speaker". Still wonder if it's worth upgrading the stock amp cord. Problem is that I need at least 6 feet and it's not going to be cheap. Re: the JJ's, I'm happy to hear that you feel the same way too with other tubes. Thought it was me for the longest time. Not very sure which version they are...just the plain old red logo.

Karl,
For my Avatar, I use exclusively in Triode mode for the very same reason. Musical preference include jazz, vocal, and classical.

Steve
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