5AR4 / GZ34 -- Best New Production Tubes?

[bob p]

I haven't seen a thread on this subject, so I thought I might as well start one...

I'm looking for current production GZ34 and I wanted to ask your opinions of who makes the best current production tube. I'd specifically like to know people's opinions on the following tubes:

JJ
Sovtek
Ruby
Sino
Fender
Valve Art

any others?

[Tom Phillips]

I use JJs. I often buy them from Ruby (Magic Parts) because they pre-screen well and have good warranty service when needed.

Additional comments:
Fender, Valve Art and Ruby are all re-sellers. They don't actually make their own tubes. Ruby does work with a Chinese factory to specify how they want some of their house brand tubes made.
Sovtek is the trade name used by New Sensor. I believe that all the Sovtek branded tubes are made in the Reflector (SP?) factory that New Sensor owns and operates in Russia.

Regards,
Tom

[galibier_numero_un]

[QUOTE=Tom Phillips;13410]I use JJs. I often buy them from Ruby (Magic Parts) because they pre-screen well and have good warranty service when needed./QUOTE]

Hi Bob, Tom ...

Pre-screening with the JJ's would appear to be important. I'm about to play with some JJ's in my soon to arrive Mission Aurora.

My primary experience with 5AR4's is in hi-fi amps, and if my experiences are statistically significant, the JJ's would appear to be sensitive to high filament voltage :eek:

A few years ago, I plugged a JJ into an amp that I was running Sovteks into. The JJ went up in flames :(

When I measured the filament voltage on the amp it was indeed quite high - a touch over 5.5VAC. Of course this led to a mini-project to drop the voltage.

Two weeks ago, I plugged a JJ into another amp I built ... same result. You'd think I'd learn from past mistakes, but of course I didn't. After dropping the Sovteks back in, I measured the filament voltage and it was 5.35VAC. I had another voltage dropping mini-project.

I have some replacement JJ's on order, because I'm still curious about their sonics.

While I don't consider this robustness issue to be a fatal flaw (of course it would be nice it they could take a sharp kick in the pants), I mention my experiences as:
cautionary - check your filament voltage first
to see if anyone else on this forum has had similar experiences.

Cheers,
Thom

[bob p]

I had heard that the original run of JJ GZ34 were defective, and that the problem has since been resolved. Is this true, or is the ongoing JJ slamming just one of the sticky internet horror stories?

[galibier_numero_un]

I had heard that the original run of JJ GZ34 were defective, and that the problem has since been resolved. Is this true, or is the ongoing JJ slamming just one of the sticky internet horror stories?

Hi Bob,

I haven't followed this topic on the web.

This recent set of JJ's I picked up was from Antique Electronics.

My guess is that Antique turns their stock of these over fairly rapidly and that my failure was from new production. Still ... who knows if this tube is out there in the 6th standard deviation. Beats me :confused:

Cheers,
Thom

[bob p]

thanks. AES/CED is probably who I'd be ordering from.

I wonder if JJ is a 6-sigma company. :p

[galibier_numero_un]

thanks. AES/CED is probably who I'd be ordering from.

I wonder if JJ is a 6-sigma company. :p

Dunno ... is the letter "sigma" in the Cyrilic alphabet :rolleyes:

... Thom

[Odd I/O]

I haven't seen a thread on this subject, so I thought I might as well start one...

I'm looking for current production GZ34 and I wanted to ask your opinions of who makes the best current production tube. I'd specifically like to know people's opinions on the following tubes:

JJ
Sovtek
Ruby
Sino
Fender
Valve Art

any others?

I have seen a lot of Amperex and Mullard GZ34 NOS go for about the same price as new producton. but you have to be patient and look around, usually.
----Just a thought