[K3cT]

I just received these from my the tube dealer. Very unusual tubes it seems, Toshiba 6J5-GT.

 

[Slade01]

I just received these from my the tube dealer. Very unusual tubes it seems, Toshiba 6J5-GT.

That is really cool! I've never seen Toshiba 6J5 before. I've tried other tube types that were Toshiba / Japan made and I was enamored by the way they sounded - especially with the imaging / clarity aspects while still being very "analog" like. Have you tried them out yet?

 

[K3cT]

That is really cool! I've never seen Toshiba 6J5 before. I've tried other tube types that were Toshiba / Japan made and I was enamored by the way they sounded - especially with the imaging / clarity aspects while still being very "analog" like. Have you tried them out yet?

No, not yet. They kinda look like Sylvania, getter at the bottom and is square shaped.

 

[K3cT]

That is really cool! I've never seen Toshiba 6J5 before. I've tried other tube types that were Toshiba / Japan made and I was enamored by the way they sounded - especially with the imaging / clarity aspects while still being very "analog" like. Have you tried them out yet?

First impression is that the Toshiba has a warm-bright tonality: the midrange is on the thick and forward side and it has a sparkly, open treble. It has a lively sound, definitely not for someone that looks for absolute neutrality.

 

[CAJames]

FYI/FWIW I was window shopping at Langrex and I see they now have 99 straight glass brown base GEC L63s. A few months ago they had 1.

Maybe they are making them???

 

[bcowen]

FYI/FWIW I was window shopping at Langrex and I see they now have 99 straight glass brown base GEC L63s. A few months ago they had 1.

Maybe they are making them???

LOL! It does make you wonder where they keep running across these stashes of very desirable tubes.

 

[nwavesailor]

A lot are found in old barns with flats of 100 from the WW2 era

 

[K3cT]

@LobalWarming

My GEC ST grey glass L63s aren't quite as open or as transparent. Nor the GEC clear straight glass L63. I would rate the later two as slightly more open up top than a good CV1988. But in the mids, prefer a good Brimar CV1988 - a bit richer and sweeter.

The Brimar CV1932 appears to have the same round plate as their CV1988 and weirdly enough, to my ears, has that Brimar mid sweetness I find a bit too addictive.

Also this is the 6SN7 thread, and I'm breaking protocol gushing about the Twins. We have the 6J5 (L63, 6C5, 12J5, 6P5, etc.) thread for that sort of unseemly behaviour.

Let’s continue here so we don’t break protocols.

My tube whisperer loaned me these Brimars. STC marked. Haven’t had a chance to test them yet but the structure looks correct when comparing to the CV1988. Are these the ones you tried?

 

[LobalWarming]

A lot are found in old barns with flats of 100 from the WW2 era

FYI: @bcowen doesn't like it when you call his barn old. It's not old, it's vintage.

 

[LobalWarming]

@LobalWarming

My GEC ST grey glass L63s aren't quite as open or as transparent. Nor the GEC clear straight glass L63. I would rate the later two as slightly more open up top than a good CV1988. But in the mids, prefer a good Brimar CV1988 - a bit richer and sweeter.

The Brimar CV1932 appears to have the same round plate as their CV1988 and weirdly enough, to my ears, has that Brimar mid sweetness I find a bit too addictive.

Also this is the 6SN7 thread, and I'm breaking protocol gushing about the Twins. We have the 6J5 (L63, 6C5, 12J5, 6P5, etc.) thread for that sort of unseemly behaviour.

Let’s continue here so we don’t break protocols.

My tube whisperer loaned me these Brimars. STC marked. Haven’t had a chance to test them yet but the structure looks correct when comparing to the CV1988. Are these the ones you tried?

Yes, I have a pair of the STC Brimars - Rochester factory. They're quite wonderful. Big open soundstage, excellent tonal balance with a sweet just lusciousness that's slightly addictive. Just slightly. Expect you won't want to give them back.

 

[maxpudding]

FYI: @bcowen doesn't like it when you call his barn old. It's not old, it's vintage.

Looks like my cat would love this vintage barn

 

[Xcalibur255]

FYI: @bcowen doesn't like it when you call his barn old. It's not old, it's vintage.

Where are the graham crackers and the frosting?

 

[ColSaulTigh]

FYI: @bcowen doesn't like it when you call his barn old. It's not old, it's vintage.

That woudn't even house 10% of his Foton collection...

 

[LobalWarming]

That woudn't even house 10% of his Foton collection...

No... but multiply that by 600 Bazillion Barns and they will almost fit

 

[Isaacc7]

I got a pair of these badboys (CV1698 version) running natively in my new amp, alongside 6336 output - sounding very nice!

I noticed that you are running your tubes at 3.33v for the heaters. I had seen that number for some of the “equivalent” tubes of the ktz41 but the ktz41 had always been listed at 4v. I had initially run mine at 4.3 volts figuring that was within the tolerance level. Then lowered it down to 4v. Now I realize that 4v is actually still beyond the 10% tolerance usually allowed for heaters if the real value is 3.33. On a whim I set mine to 3.33 and it does seem to have conquered the weirdness I had been hearing. Now I’m getting closer to what I was expecting!

I wonder why there is variation of heater voltages in supposedly equivalent tubes. Now I’ll need to reevaluate my tube combos