[gibosi]

Wonderful!

I use a pair of rare Black-base 53KU's and the getter is identical.

What a sound...

Gianluca

Just to be clear. The color of the base has absolutely no effect on the sound. Nonetheless, enjoy.

 

[VanHai]

I will receive this tube at the end of the week, please help with some information. Thanks.

 

[gkg2k]

Just to be clear. The color of the base has absolutely no effect on the sound. Nonetheless, enjoy.

Dear Gibosi,

it's good you to explain that colours don't affect sound quality, but for what regards the Cossor 53KU colours should mean something :

"tubes have the "K" factory code & were made in the UK in the 1940s or early 1950s. They are considered superior to the later Cossor 53KU with brown base & grey anode plate".

My 53KU's are black base and black plates and they sound better than a friend's brown/grey pair.

G

 

[RobertSM]

Well I definitely know there is a difference between the older fat bottle version and the newer skinny bottle version. Besides the bottle size, the internals are very different.

 

[VanHai]

Well I definitely know there is a difference between the older fat bottle version and the newer skinny bottle version. Besides the bottle size, the internals are very different.

I think my is skinny version. i just want to know how they sound, not many information about them.

 

[gkg2k]

I will receive this tube at the end of the week, please help with some information. Thanks.

Is this the skinny bottle?

Please post more pictures when you receive it

 

[gibosi]

I will receive this tube at the end of the week, please help with some information. Thanks.

This appears to be a Mullard GZ37. When Cossor stopped manufacturing vacuum tubes they still sold radios. So they sourced the Mullards for use in their radios.

And yes, some people refer to the old Cossor as the fat version and the Mullard as the skinny version.

 

[VanHai]

Is this the skinny bottle?

Please post more pictures when you receive it

I think it is skinny bottle and i will post some pictures later this week.

 

[VanHai]

This appears to be a Mullard GZ37. When Cossor stopped manufacturing vacuum tubes they still sold radios. So they sourced the Mullards for use in their radios.

Thank you @gibosi

​

 

[gibosi]

I think my is skinny version. i just want to know how they sound, not many information about them.

Do have any Mullard vacuum tubes? Drivers? Output tubes? Most Mullard vacuum tubes sound similar. And they sound different than the Cossor.

But everyone haas different ears and different gear so I have no idea which one you might prefer.

 

[gkg2k]

I own the Mullard GZ37 and it's a nice-but-not-special tube. Better than others but nothing incredibile.

Hopefully you didn't pay an extra for the Cossor logo

 

[VanHai]

Do have any Mullard vacuum tubes? Drivers? Output tubes? Most Mullard vacuum tubes sound similar. And they sound different than the Cossor.

But everyone haas different ears and different gear so I have no idea which one you might prefer.

Yes, i have 2 Mullard rectifiers GZ30 and 5G4V. I will run the Cossor against them.

 

[gibosi]

Dear Gibosi,

it's good you to explain that colours don't affect sound quality, but for what regards the Cossor 53KU colours should mean something :

"tubes have the "K" factory code & were made in the UK in the 1940s or early 1950s. They are considered superior to the later Cossor 53KU with brown base & grey anode plate".

My 53KU's are black base and black plates and they sound better than a friend's brown/grey pair.

G

If the tubes have identical construction and the only difference is the color of the base they should sound about the same. The brown base was introduced in the 1950's because it was more resistant to RF noise. But for most of us, our amplifiers are in very quiet and protected spaces. So the brown base is of no benefit in audio.

Very generally, tubes with black bases are older than tubes with brown bases, but not always. And some people think older tubes sound better. But again, not always.

 

[gibosi]

Yes, i have 2 Mullard rectifiers GZ30 and 5G4V. I will run the Cossor against them.

And I am not sure if the GZ30 and 5G4V were actually manufactured by Mullard........

 

[VanHai]

I own the Mullard GZ37 and it's a nice-but-not-special tube. Better than others but nothing incredibile.

Hopefully you didn't pay an extra for the Cossor logo

I got it for $60.00 from Ebay, so it is not a bad deal at all.