The Reference 6J5 Thread (L63, 6C5, 12J5, 6P5, etc.)

[bcowen]

I remember reading somewhere that before WW2 Svetlana bought tooling from RCA and that the Svetlana 6AS7 was inspired by RCA.

Not to go too far in the weeds in a 6J5 thread, but the '50's and early '60's Svetlana 6H5C's (6AS7G) are actually very nice sounding tubes. Better than RCA's of the same vintage to my ears. Metallurgy? Probably, if the design was the same or similar.

 

[shwnwllms]

Not to go too far in the weeds in a 6J5 thread, but the '50's and early '60's Svetlana 6H5C's (6AS7G) are actually very nice sounding tubes. Better than RCA's of the same vintage to my ears. Metallurgy? Probably, if the design was the same or similar.

I thought this whole thread was about getting too far into the weeds, too deep down the rabbit hole etc. ¯\_(ツ)_/¯

 

[bcowen]

I thought this whole thread was about getting too far into the weeds, too deep down the rabbit hole etc. ¯\_(ツ)_/¯

Lol! I live in the weeds. Just trying not to pollute the thread with the wrong tube type. I actually have a conscience. Kind of.

 

[jonathan c]

I thought this whole thread was about getting too far into the weeds, too deep down the rabbit hole etc. ¯\_(ツ)_/¯

.... no .... About getting entangled somewhere between the filament, the plate, and the getter holder .... .

 

[shwnwllms]

.... no .... About getting entangled somewhere between the filament, the plate, and the getter holder .... .

Stuck between the plate and the grid

 

[shwnwllms]

Speaking of plates and grids, pulled out my trusty Mullard (red print) DET20’s today, they never disappoint and have incredible synergy with Elrogs

 

[nwavesailor]

I bought the Mullard white print version of these and used with Elrog TM.
I was so underwhelmed with these that I sold them at a loss just to get rid of them. I have a hard time believing there is a huge difference between the white and red version but I didn't want to hunt for another quad. I tried a Russian version (?) and also sold those and the adapters!

I trust your ears @shwnwllms but these were not a driver tube for me! Thankfully they were cheap enough to try the experiment.

 

[shwnwllms]

I bought the Mullard white print version of these and used with Elrog TM.
I was so underwhelmed with these that i sold them at a loss just to get rid of them. I have a hard time believing there is a huge difference between the white and red version but I didn't want to hunt for another quad. I tried a Russian version (?) and sold those (and the adapters!) quickly.

I trust your ears @shwnwllms but these were not a driver tube for me! Thankfully they were cheap enough to try the experiment.

I have the following

Russian 6C8C - decent but not as great as 6S5S or early metal base 6C2C, I need to give them another listen though

Mullard VR135 - warm, syrupy, gooey. I would rate these as some of the warmest drivers I’ve heard, even for a Mullard

Mullard DET20 (red print) - mil spec, sound nothing like the VR135’s. Sound nothing like a Mullard actually. House sound is absent on this one. Very dynamic, resolving, punchy articulated bass with sparkling highs. I recall not caring for them at first but I think I was expecting more of a Mullard house sound and was let down. More I listen to them, the more I like them. They are very different than my other two CV6’s

The VR135’s have white print are you referring to those or is there a mil spec DET20 with white print? (If there is a DET20 white print I haven’t heard those)

 

[nwavesailor]

I also tried the GEC version

 

[nwavesailor]

Here were the Mullards

 

[Designsfx]

I’ve never owned the DET but do have its cousin in the “7193” and they never disappoint either!

 

[shwnwllms]

I also tried the GEC version

Always wondered about these. Are they anything like the GEC 6J5G L63 Shouldered Grey Glass?

Here were the Mullards

Interesting. There’s a huge difference between G73-R black & red label. I’ve got no idea if there is a difference in these DET20 white & red but it’s a possibility if it’s different years of production / factories

 

[nwavesailor]

I'm glad they work for you!
I only have 2, G-73-R neither with paper labels.

The writing looks identical to this pair:

 

[shwnwllms]

Here’s a couple of photos of the internals of the Mullard DET20 red print (if anyone has a white print to compare against)

 

[Designsfx]

Everyone- please help me out here! I’ve just received this quad of KenRad VT-76 and making my best guess at the date codes. All tubes came in new boxes and the only code shown is “K 3”. My best guess is end of May 1943- any other ideas on this? Thanks in advance!