[2359glenn]

The GZ34 is a great tube but not a looker plain little tube

 

[UntilThen]

The GZ34 is a great tube but not a looker plain little tube

Yup the GZ34 that I got is as good as the metal base version. It will be a good contrast to the GEC U52. I will get a GZ37 later.

 

[2359glenn]

The GZ34 metal base is a great tube I have one also have a GE that is almost as good.
I just prefer the looks of the GZ37.
The GZ34 and GZ37 have the lower voltage drop and I feel are the better tubes. Plus slow turn on they are not direct heated.

 

[UntilThen]

Glenn are you referring to the fat or skinny GZ37? There are 2 different types.

 

[2359glenn]

Electrically I like them both but the fat bottle looks so nice. The skinny Mullard might be better.

 

[UntilThen]

The skinny Mullard gz37 is less than half the price of the fat bottle 53ku. As I have already purchased a U52, I can make a concession and get the skinny instead.

I'm getting a crash course in rectifiers here. Oh by the way, can a plug in hexfred ss rectifier work with this amp, since you said that the 3DG4 is too high.

 

[2359glenn]

Yes I can make you a HEXFRED rectifier that will plug into the rectifier socket. They are great but don't look special
Just a tube base with the diodes n it.

 

[UntilThen]

Thanks I would like to try the hexfred too but I have a feeling the EL11 is more transparent and a warmer rectifier would do a better job. Pure speculation. Only hearing the finished amp would I be able to tell.

This is a history of EL34. You probably would have seen it. Shows all the EL type tubes, including EL11, EL12 Spez that precedes the EL34. Right click to translate to english.
http://www.jogis-roehrenbude.de/EL34-Story/EL34-Story.htm

 

[gibosi]

For those interested in the Raytheon CK 5694 double triode, there are a pair on eBay:

https://www.ebay.com/itm/173330819442

Current bid is 51 US dollars for the pair.

 

[UntilThen]

Similar to 6N7G but with different pins. Guess you will need another adapter? Have you use it before Ken?

 

[UntilThen]

Are you kidding me?

Stolen from the net....

The Raytheon CK-5694. Electronically similar to a British made ECC32 / CV-181. I am using them as 6SN7 GTB substitutes to drive a pair of 845s. They were ignored because they have a non-standard octal pin-out, which means that they require a small adapter. Professionally made adapters to convert them to a 6SN7 pin-out, are currently available on Ebay for $15.90 each. They feature lower noise, more dynamics, and are better across the entire frequency spectrum. Easily outperform the Mullard & Chelmer Valve ECC32 / CV-181, which go for $600 to $650 a pair at "Tube World", when available.. These tubes are be careful what you ask for, They will reproduce every thing that comes from your source, the good, the bad, and the ugly. Analog, in every sense of the word. If you like digital effects, these are not for you. I am listening to them through custom four-ways, using only first order cross-overs, they allow no room for error. The Raytheon CK-5694, easily the best NOS tube that I have ever owned. One matched & balanced pair available at $400. THESE ARE NOT DIRECT 6SN7 SUBSTITUTES, PLEASE CONSULT AN AUDIO TECHNICIAN BEFORE USING IN YOUR EQUIPMENT! I have a customer who is using them in place of a 6DJ8 / ECC88, in a DAC, with a vacuum tube based output stage, with great results!

 

[whirlwind]

For those interested in the Raytheon CK 5694 double triode, there are a pair on eBay:

https://www.ebay.com/itm/173330819442

Current bid is 51 US dollars for the pair.

Nice...Ken

Are you kidding me?

Stolen from the net....

The Raytheon CK-5694. Electronically similar to a British made ECC32 / CV-181. I am using them as 6SN7 GTB substitutes to drive a pair of 845s. They were ignored because they have a non-standard octal pin-out, which means that they require a small adapter. Professionally made adapters to convert them to a 6SN7 pin-out, are currently available on Ebay for $15.90 each. They feature lower noise, more dynamics, and are better across the entire frequency spectrum. Easily outperform the Mullard & Chelmer Valve ECC32 / CV-181, which go for $600 to $650 a pair at "Tube World", when available.. These tubes are be careful what you ask for, They will reproduce every thing that comes from your source, the good, the bad, and the ugly. Analog, in every sense of the word. If you like digital effects, these are not for you. I am listening to them through custom four-ways, using only first order cross-overs, they allow no room for error. The Raytheon CK-5694, easily the best NOS tube that I have ever owned. One matched & balanced pair available at $400. THESE ARE NOT DIRECT 6SN7 SUBSTITUTES, PLEASE CONSULT AN AUDIO TECHNICIAN BEFORE USING IN YOUR EQUIPMENT! I have a customer who is using them in place of a 6DJ8 / ECC88, in a DAC, with a vacuum tube based output stage, with great results!

This sounds pretty cool, auction is for a pair of tubes the OTL only need 1!

 

[gibosi]

Are you kidding me?

Stolen from the net....

The Raytheon CK-5694. Electronically similar to a British made ECC32 / CV-181. I am using them as 6SN7 GTB substitutes to drive a pair of 845s. They were ignored because they have a non-standard octal pin-out, which means that they require a small adapter. Professionally made adapters to convert them to a 6SN7 pin-out, are currently available on Ebay for $15.90 each. They feature lower noise, more dynamics, and are better across the entire frequency spectrum. Easily outperform the Mullard & Chelmer Valve ECC32 / CV-181, which go for $600 to $650 a pair at "Tube World", when available.. These tubes are be careful what you ask for, They will reproduce every thing that comes from your source, the good, the bad, and the ugly. Analog, in every sense of the word. If you like digital effects, these are not for you. I am listening to them through custom four-ways, using only first order cross-overs, they allow no room for error. The Raytheon CK-5694, easily the best NOS tube that I have ever owned. One matched & balanced pair available at $400. THESE ARE NOT DIRECT 6SN7 SUBSTITUTES, PLEASE CONSULT AN AUDIO TECHNICIAN BEFORE USING IN YOUR EQUIPMENT! I have a customer who is using them in place of a 6DJ8 / ECC88, in a DAC, with a vacuum tube based output stage, with great results!

The 5694 is essentially a 6N7G with separate cathodes. And given its powerful heater, it is most comparable to the ECC32. But as a result of the decision to use a non-standard pin-out, these were a flop in the market place. To the best of my knowledge, no major manufacturer included the 5694 in their radio sets. In the end, Raytheon simply didn't make all that many of them and they are pretty rare.

It seems that the guy quoted above who claimed the 5694 is the best double-triode ever made managed to round up a number of these rare tubes and evidently sold them for $400 a pair. But of course, this is largely marketing hype. Yes, I have this tube, and yes, I think it is very, very good, but no, I do not think it is the best double triode ever made. lol

So I wouldn't encourage paying anywhere near $400 for the pair, but they are rare and they do sound good....

 

[UntilThen]

With $400 I will buy a juicy rectifier. The OTL amp is sounding incredible now. I'm in a state of zen. Pure calm and bliss. To prospective owners of the OTL amp, you've no idea what's coming your way.

But I need to visualise how my next amp will look. So I enlarge Sam's amp and picture it having the larger 300b transformers, with EL11 and EL12 spez in place. It's looking really good.

 

[whirlwind]

Oh heck, with $400 you can buy a few juicy rectifiers, lol.