[Oskari]

It was made by Standard Radio of Sweden but I don't know if this company was owned by Ericsson.

Nope. It was an ITT company like STC in UK and Standard Elektrik Lorenz in Germany.

 

[attmci]

Very similar to RCA 5962, here is a pair of SS33S30 with gold plated pins.

They were used in Beaufort gun turrets on vessels as they could withstand the hostile environment.

Are these nice sounding tubes? Or just rare? How do they compare to the similar tubes?

 

[UntilThen]

I'm astonished at how similar sounding the Sansui AU-717 is to the GOTL with Sylvania 6sn7w metal and 6 x 6bx7gt.

 

[2359glenn]

I was thinking last night while building a amp.
The EL3N amp uses a CCS (constant current source) on the driver EL3N.
What I was thinking was to use this on the OTL driver with a pot on the amp to adjust the plate current of the driver.
This would allow to get the perfect operating point for all tubes rolled in this position.
Or would this make things to complicated??? To many switches and knobs.
What do you guys think?

 

[heliosphann]

I was thinking last night while building a amp.
The EL3N amp uses a CCS (constant current source) on the driver EL3N.
What I was thinking was to use this on the OTL driver with a pot on the amp to adjust the plate current of the driver.
This would allow to get the perfect operating point for all tubes rolled in this position.
Or would this make things to complicated??? To many switches and knobs.
What do you guys think?

I love playing with knobs...

hehehe

 

[gibosi]

I was thinking last night while building a amp.
The EL3N amp uses a CCS (constant current source) on the driver EL3N.
What I was thinking was to use this on the OTL driver with a pot on the amp to adjust the plate current of the driver.
This would allow to get the perfect operating point for all tubes rolled in this position.
Or would this make things to complicated??? To many switches and knobs.
What do you guys think?

I really like the idea. But it does the beg the question: How is the perfect operating point determined? I assume it can be derived from the data sheets? Perhaps from one of the graphs?

 

[Althalus]

I was thinking last night while building a amp.
The EL3N amp uses a CCS (constant current source) on the driver EL3N.
What I was thinking was to use this on the OTL driver with a pot on the amp to adjust the plate current of the driver.
This would allow to get the perfect operating point for all tubes rolled in this position.
Or would this make things to complicated??? To many switches and knobs.
What do you guys think?

I'm like a dog that is asleep and suddenly you see one ear popping up.......
I have the same question as gibosi. And as addition does having an additional knob cause more noise?

 

[whirlwind]

This may be a great idea, but like the others...what criteria for the operating points.

 

[rosgr63]

A table with the operating points and a meter is all that's needed to set the pot.

 

[rosgr63]

Are these nice sounding tubes? Or just rare? How do they compare to the similar tubes?

They have the 5692 sound signature to me.

 

[Monsterzero]

Heres a question from the less experienced tube rolling brigade...

If one can achieve perfect operating points determined by referencing data sheets via a knob adjustment,what would that accomplish in terms of sonic reproduction?
It seems it could be an optional addition. It might be overkill for the noob,unless of course the sound is night and day.

Would it be akin to the 5998 optimizer switch you already offer as an option?

 

[rosgr63]

Heres a question from the less experienced tube rolling brigade...

If one can achieve perfect operating points determined by referencing data sheets via a knob adjustment,what would that accomplish in terms of sonic reproduction?
It seems it could be an optional addition. It might be overkill for the noob,unless of course the sound is night and day.

Would it be akin to the 5998 optimizer switch you already offer as an option?

If it measures good and sounds bad, it is bad. If it sounds good and measures bad, you've measured the wrong thing - Daniel R. von Recklinghausen

 

[gibosi]

A table with the operating points and a meter is all that's needed to set the pot.

Of course, armed with such a table the adjustment would be easy. But again, I suspect that someone, perhaps someone in this forum, would have to put this table together first.

 

[rosgr63]

Of course, armed with such a table the adjustment would be easy. But again, I suspect that someone, perhaps someone in this forum, would have to put this table together first.

And somebody would set the wrong voltage............

 

[gibosi]

Heres a question from the less experienced tube rolling brigade...

If one can achieve perfect operating points determined by referencing data sheets via a knob adjustment,what would that accomplish in terms of sonic reproduction?
It seems it could be an optional addition. It might be overkill for the noob,unless of course the sound is night and day.

Would it be akin to the 5998 optimizer switch you already offer as an option?

Theoretically, tubes biased at their perfect operating points should sound better. But perhaps this is not always true?

For example, an ECC32 installed in a 6SN7 socket is not biased properly. And yet, some claim it sounds better than any properly biased 6SN7.

So maybe, just maybe, the reason the ECC32 sounds so great is exactly because it is biased incorrectly? Or maybe, just maybe, if it was biased correctly it would sound even better?

Being able to adjust the bias would allow us to determine if the perfect bias actually does sound better in each case.