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Jolida 202a Tube Rolling Question 12ax7 12at7

Hi guys, a while back I purchased a jolida 202A to power my desktop speakers. I like the combination very much for accoustic/percussion music as nothing can quite beat it. However my $200 14 watt hong-kong amp is better for rock.
Before testing the other amp I thought it was simply a property of the speakers. But after putting the Jolida in my main setup I'm experiencing the same downfalls.

I don't really know how to pick tubes in order to get the qualities I'm looking for, so I was hoping that you guys could help out.

What I like about the sound now:
-Crisp details throughout the frequency spectrum
-Very speedy attack and decay on accoustic instruments

What I don't like:
-Very dry quality in the upper mids / lower HF
-Not enough tube bloom and warmth, too sterile
-The distortion at high power isn't like my little class A, (which just tends to get more blended and bloomy) but instead sounds rather grating in the high end and loses the bass.

Tubes I'm using right now:
4x JJ E34L's - Power
2x Electro-Harmonix 12ax7's in the preamp circuit
2x PhillipsECG 12AT7's as power drivers

I believe that the amp originally came with 4x 12AT7's though.
robxmccarthy

Showing 6 responses by robxmccarthy

robxmccarthy OP
10 posts
 
How do you guys feel about the Ei 12AX7's? It's supposedly based on the tele long plate design.
robxmccarthy OP
10 posts
 
Forgot one detail

What I want:
A warmer fuller sound (less dry and sterile)
More in the upper bass (for rock)

Thanks for any suggestions
robxmccarthy OP
10 posts
 
Thank you very much for the prompt, informative responses.

I ordered a pair of Tung Sol 12ax7's and a pair of the GE 12at7s.

I'm trying to figure out what specific mullard is being refered to. Will any of the blackburn series 12ax7's do, or is there a specific model I should look into?
robxmccarthy OP
10 posts
 
Hmm the Tung-Sol that I ordered was a standard new 12ax7. Is there really a big difference between that and the gold pin version? I just sort of assumed it would have better contacts. Hope I won't be disappointed.
robxmccarthy OP
10 posts
 
After letting the tung-sol 12ax7's burn in for a bit I'm willing to make some observations in the difference between these tubes and the EH's.

Unlike the E-H tubes the Tung-Sol's aren't dry sounding. There isn't that 600+ hz air, and low volume level playback benefits immensely.

However, there's still some problems. The TS tubes seem to play a bit hotter in the upper end. There's some added sibilance and at higher volume levels rock playback can become a bit grating. I'm not saying that this is a problem for all speakers; mine happen to be rather bright to begin with. Equalization fixes the problem to some degree, and it's definitely easier to fix some frequency ineqaulities than the overall sonic character.

I'm probably going to try out some mullards.
robxmccarthy OP
10 posts
 
I'll try out some mullards and see what the result is.

The Teles are very intriguing, but the price range is far from attractive.
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