[Phantaminum]

@gibosi

Awhile back I had purchased two tubes from the UK and one of them had an OSRAM BVA sticker. Designation under the sticker has it as 12SN7/B36. What’s a good guess in your experience on who the original manufacturer is? It has black ladder plates and sounds fantastic with the 6BX7s. I’m hoping to purchase another one. Glad I didn’t return them.

 

[gibosi]

@gibosi

Awhile back I had purchased two tubes from the UK and one of them had an OSRAM BVA sticker. Designation under the sticker has it as 12SN7/B36. What’s a good guess in your experience on who the original manufacturer is? It has black ladder plates and sounds fantastic with the 6BX7s. I’m hoping to purchase another one. Glad I didn’t return them.

To my eyes it looks like a Philips 12SN7GT. Philips manufactured this tube at Endhoven, Holland, and Bruxelles, Belgium. Typically, the production code was printed on the bottom of the base between the pins.

 

[Phantaminum]

To my eyes it looks like a Philips 12SN7GT. Philips manufactured this tube at Endhoven, Holland, and Bruxelles, Belgium. Typically, the production code was printed on the bottom of the base between the pins.

Thanks @gibosi

 

[mordy]

Things move fast here, by I am trying to catch up.Here is another Osram BVA stickered tube:

It is a GEC A1834/6AS7G. Tried to imitate UT's tube glow picture, but even though these came from Stavros, they light up a little less:

The GEC 6AS7 has a lot of energy and sound beautiful with a luscious mid range as well as being extremely detailed with the Mullard ECC31.
But based on a short listen I find the Cetron 6336B/ECC31 more relaxing to listen to.
Both are top tier tube combinations in the GOTL. However, due to the expense and rarity of the GEC 6AS7 they will be reserved for a sunny Sunday afternoon drive, and I will use the 6336B as a daily driver (oops, I meant power).
I know people will tell me to just enjoy them and don't worry, but something is bothering me when listening - don't know exactly what.
Too much emphasis on detail?
Next: To try to revive a silent Raytheon 6336B that lights up but does not produce sound any more. I asked before for advice but nobody answered - any suggestions?

 

[UntilThen]

You had asked similar q before. Do You wanna a lot more gains? Can you use 6sl7?

If the answer is yes. You will be fine.

I've not ask about 12AT7 before.

I've been using Tung Sol 12SL7GT bgrp for a good while now and it didn't sound much louder than a regular 6sn7. It's one of my fav tubes.

Amplification
6sn7 - 20
6SL7 - 70
12AT7 - 60
12AX7 - 100

 

[UntilThen]

yes the 12AT7 will be fine. Don't know how it will sound but sure it will sound good it is a good sounding tube.

Thanks Glenn. It is a very rare and well known tube but not sure if I want to chase more expensive tubes.

 

[mordy]

Thanks Glenn. It is a very rare and well known tube but not sure if I want to chase more expensive tubes.

Hi UT,
Did not know that I had such a rare tube:

A quick look at eBay shows a whole bunch of them for $10 and less.
Did you know that the red print on a Sylvania box means replacement tube?

 

[2359glenn]

Thanks Glenn. It is a very rare and well known tube but not sure if I want to chase more expensive tubes.

They are not expensive and not rare easy to get

 

[UntilThen]

Mordy, it's not just any 12AT7. The Valvo 6201 blue label gold pins are the rare ones.

 

[mordy]

Mordy, it's not just any 12AT7. The Valvo 6201 blue label gold pins are the rare ones.

Not familiar with that one, but I have heard of Johnny Walker Blue Label lol.

 

[UntilThen]

Correct. Not all Johnny Walker are the same. Check out the 6201 Valvo blue label here.

http://www.jacmusic.com/nos/ECC81.htm

 

[mordy]

Seriously though, I would like to report on three patients successfully treated at MTRC that all seems to have regained full health:
Patient A (TS 6BGRP): Suffered from severe Hummings Disease. Treated with pressurized abdominal wrap and localized heat treatment.
After applying the wrap and two heat treatments totally free of symptoms.
Patient B: (Syl 6W) Suffered from Schizophrenia with periods of calm and then uncontrollable explosive outbursts and loud noisemaking. After three intensive heat treatments returned to normal behaviour.
Patient C: (TS Arcturus 12BGRP) Suffered from Kellog's Disease of Snap, Crackle and Pop. After three heat treatments with increasing heat, returned to normal.
Unfortunately, Patient D (Ray 6336) continues to baffle the staff. The patient looks perfectly normal and red, but refuses to talk. Heat treatments did not cause any improvement - as silent as before, although patient history indicates full recent control of all communicative facilities.
We will endeavour to consult with other specialists in the field to see if we can cure this (not so rare?) condition.



.

 

[rnros]

You may be limited on one tube mode with headphones , depending on the headphone and how loud you listen.
I can listen with one tube mode with my Ori, but I have the volume maxed out....it sounds nice.

With the HD800 and the Atticus I can listen between 2 and 3 o'clock

You can switch between the two modes on the fly without hearing any noises, no clicking or noise of any kind when switching on the fly.
Just make sure you turn down the volume before switching to the two tube mode or you will blow your ears out.

The amp can be sensitive to back round noise in two tube mode, since one tube mode is dead silent, it makes you notice any noise, lol.

Thanks, whirlwind. Good info!

 

[attmci]

I've not ask about 12AT7 before.

I've been using Tung Sol 12SL7GT bgrp for a good while now and it didn't sound much louder than a regular 6sn7. It's one of my fav tubes.

Amplification
6sn7 - 20
6SL7 - 70
12AT7 - 60
12AX7 - 100

Oops. My bad. Getting old?

 

[attmci]

Mordy, it's not just any 12AT7. The Valvo 6201 blue label gold pins are the rare ones.

I agree. Go for it!