Tube replacement Tests UA 2-610

[JuergenW]

Hello.

We recently did a test with different ECC83 tubes in an UA 2-610 preamp,
because we were wondering which sonic difference would occur...

Test Setup:

Neumann TLM103 -> VOVOX Cable -> UA2-610 -> ADT-Line-In -> RME ADI8-S A/D (@internal sync)

Settings on 2-610: IMP. 2 K ; GAIN -10 ; OUTPUT 7 ; No EQ applied

Recorded in 24 Bit/44.1 KHz with same mic distance (ca. 20 cm) and the same vocalist :wink:

Tubes tested:

Original JJ Tubes delivered with 2-610
Telefunken ECC83 (New old stock)
Valvo ECC83 (New old stock)

Our favourite (at least for this mic and vocalist) is the Telefunken
which has a more open and less bassy sound than the original JJ´s.
The Valvo turned out to be less bright than the others without sounding muddy.


Anyone interrested may download the test files:

http://www.juergenwirtz.com/tubetest/610jj.aif

http://www.juergenwirtz.com/tubetest/610telefunken.aif

http://www.juergenwirtz.com/tubetest/610valvo.aif

regards,
Juergen

 

[Staccato]

You left out quite a few contenders. But out of the three, back to the tele?

 

[JuergenW]

You´re right. There are more companies.

But the Telefunken makes the 610 shiny - I like it most for vocals.

Valvo is very warm - great for E-bass or classical vocalists.

 

[Staccato]

That's good info, I'll look forward to letting you know about RCA, vs Tung-Sol. vs ? any other has been USA manufacturer. BTW, how do the Mullards square up?

 

[JuergenW]

No idea! Amprex and Mullard´s 12AX7 are kind of seldom (and fucking expensive) in germany. RCA and most american N.O.S. even more.

If you checked some tubes please let me know! I can only advice
to get a pair of good Telefunken.

 

[Staccato]

Off to a good start here, picked up a bag of '50's RCA Blackplate 12AX7's on ebay. They didn't know what they had I guess. $30 for 20 Blackplates, all used '50's, look like organ pulls.

 

[cAPSLOCK]

FWIW, These guys (Mojo Musical Supply) are good on price and offer some interesting selection:
http://yatuc.com/3lb

cAPS