[aragon63]

 Picked up this one on eBay. It's 1941 Sylvania 5U4G ( J790 ) black ribbed plates , bottom D getter ( test NOS )

 

[JakeJ]

Sweet!  Don't keep us in suspense, what piece of equipment are you going to use it in?

[Tom Bombadil]

I have one of those, not quite as old.   Love the way it looks.   Works fine.   I don't hear any differences between like rectifier tubes in my amps so it sounds the same as all of my other 5U4G tubes, but I like having one.

[FullRangeMan]

Nice, any amp photo in action ?
Made us an favor and dont put untested tubes in your beloved amp, especially this age, 1941 is a lot of time for air build inside.

[FullRangeMan]

I have one of those, not quite as old.   Love the way it looks.   Works fine.   I don't hear any differences between like rectifier tubes in my amps so it sounds the same as all of my other 5U4G tubes, but I like having one.

Hm, could be more specific?

[aragon63]

Nice, any amp photo in action ?
Made us an favor and dont put untested tubes in your beloved amp, especially this age, 1941 is a lot of time for air build inside.

 Amp is nothing special . It's el 34 se , about 12 watts . I'm currently running 1958 Sylvania JAN CHS 6SL7WGT, 1941 Sylvania 5U4G rectifier & Golden Lion KT77. Recently replaced yellow Benic caps with Jentzen Silver Z caps. Huge improvement in detail , air and soundstage .


 

[FullRangeMan]

Congratulations, looks a classic desing.
It is UltraLinear?

[Tom Bombadil]

Hm, could be more specific?

I thought I was quite specific.  It sounded just like every one of my other 5U4Gs sound.   It's not like the audio signal path passes through the rectifier.  As long as a rectifier is within specs, they sound the same in my amps.  Of course a 5U4G sounds different from a 5V4GA vs a GZ34.   

[FullRangeMan]

OK thanks Tom.