Head-Fi.org › Forums › Equipment Forums › Headphone Amps (full-size) › Darkvoice 336 + 336i Tuberolling [ tubes ]
New Posts  All Forums:Forum Nav:

Darkvoice 336 + 336i Tuberolling [ tubes ] - Page 98

post #1456 of 1496

That's good news about the hum.  I have never seen a pair of RCA tubes with black glass before.  I'm thinking those are not RCA made - probably National Union?  or maybe Ken-Rad?  In any case, RCA date codes can be hard to figure, but I am guessing that yours are made in the 17th week of 1956,  based on this from the RCA Date Code guide I have:

 

 

Quote:
From 1-46 to 8-56: For all tubes, the code was the last digit of the year) plus a
month indicator comprising the RMNEIh week code, quantized to 04 (Jan.), 08
(Feb.), 52 (Dec.), etc. Included is a "sales basis" code: a dash between year and month
indicated tubes sold on an adjustment basis; no dash indicates sale on an allowance-inlieu-
of-adjustment basis (i. e., renewal vs. OEM business). This scheme covers privatebrand
tubes, except where a buyer's special code applies, but not Government tubes.

Gear mentioned in this thread:

post #1457 of 1496

hi, Skylab, thanks for the info. actually i only have one, not a pair. it's the same tube shot twice in different angles. cannot see thru the black glass so no way of telling the construction. the only transparent bit is the top. will post a picture later this week and hope that will help you solving the mystery. :) shiaokun

post #1458 of 1496

the top view of the mystery black-glass RCA 6SN7 GT. hope this will help identifying which company made this...

P1510386.JPG

post #1459 of 1496

installed a Sylvania GTB. yellow label. i suppose that 'CC' is a date/facory code? came with a box. you can see the hand-written price: 2.15. :)

 

P1510396.JPG

P1510397.JPG

P1510398.JPG

P1510399.JPG

P1510400.JPG

P1510401.JPG

post #1460 of 1496

back to GE tubes. think it has been more than a year since...

P1510416.JPG

P1510417.JPG

this is a 'new' 5-star 6080 i got recently. it's not in the same nice cosmetic condition as last year's pair. sounds good nevertheless. smily_headphones1.gif i suppose somewhere down the road i might get a tube tester...

post #1461 of 1496

switched on a 6AS7G from Chatham. the front is still the GE. no hissing. smily_headphones1.gif

 

listened to 'Rachmaninoff plays Rachmaninoff' from RCA, done by the Zenph Studios. the second half of the CD is the 'Binaural Stereo Version' of the first half, recorded with microphones placed on a dummy head. they claim this to be 'the ultimate headphone experience.' i think i need to listen to it a few more times to decide...

 

P1510427.JPG

 

post #1462 of 1496

I'm so jealous right now!!! i still haven't started tube rolling my amp after having it for 3 months but it looks like ill have some cash this weekend to buy tubes, hit me up if any of u guys got some to sell

post #1463 of 1496

switched on a 6SN7WGTA from TUNG-SOL. probably the most 'exotic' 6SN7GT in my collection. smily_headphones1.gif

 

P1510429.JPG

P1510430.JPG

i've guessed USN = U.S. Navy. what about CTL? and does 739 mean anything? production year-week?

 

it hissed a little in the beginning, but then quieted down before the first CD finished.

post #1464 of 1496

CTL is the 3 letter Military code for Tung Sol.  Sylvania is CHS, RCA is CRC, Hytron was CHY, Raytheon was CRP, National Union was CNU, and GE was CG.

post #1465 of 1496

thanks!

post #1466 of 1496

this week's new combo:
Westinghouse 6080 with a date code 70-17
Raytheon 6SN7 GTB with a code C18

 

P1510436.JPG

P1510437.JPG

the sound is more 'forward' than the previous set-up, feeling like sitting close to the stage.

post #1467 of 1496

Hmm, this thread is quite interesting.

 

Tube rolling seems a bit complex though.


Edited by Katun - 11/8/10 at 1:04pm
post #1468 of 1496

refresh my memory, please...

 

after not having listened to my 336i in about a year, i have a newly regenerated interest in it.  one thing i don't remember is whether or not i should keep a load connected while it warms up.  what is the recommended procedure for warm-up these days?  keep cans connected or does it make any difference (to the amplifier output stage)?

 

THANKS!

 

Also:  I'm considering moving away from the Senns and perhaps try some Beyers.  I'm specifically interested in the 600 ohm versions of either the dt-880 or 990.  Will the 336i drive them suckers?  I believe my HD650s are of the older, 300 ohm variety, but can't recall for certain.  The DV has no problem driving those...


Edited by Jo6Pak - 11/17/10 at 2:04pm
post #1469 of 1496
Quote:
Originally Posted by Jo6Pak View Post

refresh my memory, please...

 

after not having listened to my 336i in about a year, i have a newly regenerated interest in it.  one thing i don't remember is whether or not i should keep a load connected while it warms up.  what is the recommended procedure for warm-up these days?  keep cans connected or does it make any difference (to the amplifier output stage)?

 

THANKS!

 

Also:  I've considering moving away from the Senns and perhaps try some Beyers.  I'm specifically interested in the 600 ohm versions of either the dt-880 or 990.  Will the 336i drive them suckers?  I believe my HD650s are of the older, 300 ohm variety, but can't recall for certain.  The DV has no problem driving those...


Rollin', Rollin', Rollin'....beerchug.gif

 

I always have a load on the DV when I power up, whether I'm using headphones or as a pre.
 

post #1470 of 1496

thanks for that.  i remember doing it routinely before, but then i recall at some point someone saying it wasn't necessary.  guess i'll continue to do it...


Edited by Jo6Pak - 11/17/10 at 5:38pm
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Headphone Amps (full-size)

Gear mentioned in this thread:

Head-Fi.org › Forums › Equipment Forums › Headphone Amps (full-size) › Darkvoice 336 + 336i Tuberolling [ tubes ]