[Xcalibur255]

Quote:

I'm using 6SN7's as driver tubes in my SET amplifier. The output stage of the 6SN7 is coupled with the output tube grid by a capacitor. I have been thinking of changing that capacitor for an interstage transformer, mainly due to the voltage limitation of the capacitor, which limits the power I could be drawing from my o/p tube (i.e, could I go up with the voltage, I could have 30% more power.)
I was told by a transformer manufacturer that the 6SN7 is not a good tube to use with interstage transformers, and that I would be better off with the 6BL7 due to its lower o/p resistance. I wonder if anybody here has had some experience with this, or would have an informed opinion about this...

You could try dropping this question in the 2359glenn Studio thread too.  He has used the 6BL7 and told me it is a great tube.

 

[rosgr63]

Glenn can most certainly provide this info, he probably has tried that configuration any way!

 

[2359glenn]

Quote:

I'm using 6SN7's as driver tubes in my SET amplifier. The output stage of the 6SN7 is coupled with the output tube grid by a capacitor. I have been thinking of changing that capacitor for an interstage transformer, mainly due to the voltage limitation of the capacitor, which limits the power I could be drawing from my o/p tube (i.e, could I go up with the voltage, I could have 30% more power.)
I was told by a transformer manufacturer that the 6SN7 is not a good tube to use with interstage transformers, and that I would be better off with the 6BL7 due to its lower o/p resistance. I wonder if anybody here has had some experience with this, or would have an informed opinion about this...

What is the output tube the 6SN7 is tryind to drive ?

 

[GrindingThud]

6SN7 looks kinda fun! Anyone ever stuff one on top of a WA3?

 

[mikey8811]

Quote:

I'm a big fan of all the Hytron GTs, they are consistently underrated tubes.  Some of the most lucid mids you will ever hear.  Their only weakness is loose bass, but it isn't so bad it gets in the way of enjoying what the tube does well.

Hi
 
I got the Hytron GTB's. I placed them in the balanced input buffers of my Cary SLP 05 (tubes 3 & 6) with a quad of RCA Grey Glass in the phase splitter positions (tubes 1, 2, 4 & 5). They are fast and quiet tubes. Compared to the Sylvania GT Chrome Domes that Xcalibur likes, they have a fuller midrange and low end. Because of the speed they work better with rock and pop music even though the bass was a bit tubby but there seemed to be more of it than with the Syl's. There was however, also more treble and sibilance. In this combination, I enjoyed them more than the Syl's with rock and pop. However, with jazz, I enjoyed the Syl's more as the treble was more delicate.
 
I also tried a quad of them in the phase splitter positions (tubes 1, 2, 4 & 5) with RCA Grey Glass in the balanced input buffers (tubes 3 & 6) - this combination seemed to accentuate the treble sibilance but the speed and low end was pretty good.
 
I've read some comments that they are similar in sound to the Tungsol's - not the BGRP's which I could not afford but the clear glass ones with or without mouse ears. Would these give me the speed of the Hytron GT's with a more delicate treble like the Syl's?

 

[Xcalibur255]

IMO no not really.  Tung Sols are well extended but also a bit lit up at the top more so than Hytrons are.  The actual BGRP Tung Sol would give you exactly what you want, but at high cost.  The later Tung Sols are good tubes, but delicate isn't one of their qualities.  If you are looking for a full lower range and polite treble that isn't dead or dark you might like the Japanese tubes such as the ITT or Hitachis. 

 

[Silent One]

I own a pair of ITT (Japan) 6SN7GTB's and was pleasantly surprised by them...

 

[jamato8]

The Japanese went for very hard vacuum on their tubes. They took it very serious and in general, the Japanese tubes have always been underrated. They last a long time and maintain their sound. I have 5 EL34's, which are power tubes, made in Japan. I don't know the manufacture as they are the only ones of style I have, that I have ever seen. They have 1000's of hours on them and still sound better than any EL34 I have ever heard and I have NOS Mullards and Amperex.

 

[mhamam]

emission labs 1605

 

[2359glenn]

Quote:

emission labs 1605

The EML1605 is similar to a 300B except it can take higher voltage and put out more power. A 6SN7 has a hard time driving a 300B so I
would think the same for the 1605.  The capacitor is not the problem the 6SN7 doesn't have enough drive to drive the 1605.
  You might try a 6DN7 1/2 is like a 6SN7 and 1/2 is like a 6BL7 plus this tube don"t sound bad. If you have 500 volts B+ for the 1605
you can decouple The 500 volts with a 1K 10 watt resistor and 20uf 630 volt capacitor to ground and use a 25K 25 watt resistor to the plate
of section two pin 2 of the 6DN7 then the capacitor to the grid of the 1605.

 

[rosgr63]

Glenn, I feel so hopeless when I read your excellent recommendations!!!!!!!!!!!!
 
No wonder your amps sound so good!

 

[dminches]

Stavros, that's because we spend time driving the car while Glenn is under the hood.

 

[Silent One]

Well 

 stated, dminches! I'm going to have to do more to park the car and get up in there....and learn more.

 

[DefQon]

Anyone tried some NOS Valvo rebrand 6SN7's? Has gold contacts and very dark black plates. Big O getter.

 

[Zub-a-Roo]

What is the opinion on the Sophia electric grade A for $100.00 off eBay. I am leary about the purchase.