Rectifiers

[Don]

My Super Reverb calls for a GZ34 rectifier. I have a good 5R4 and a good 5U4.

Can I use one of them? If so, what kind of results would I expect?

I have a Mullard GZ34 in the VR but that's not coming out anytime soon!

[Totally bored]

Here's a good link that explains it all.

You'll get more sag with the 5u4 and even more with the 5r4. You'll need to Rebias your amp and then there's the 2 amp filament current going to 3 amp filament current issue.


FWIW, I just blew a JJ's GZ34 in my fairly new DRRI and decided to order 2 from here. Came in 3 days with economy shipping and cost $38. Funny how my old GZ34 Mullard in my 69 Princeton Reverb still works after 40 years.

[Cygnus X1]

A 5R4 is a GZ34, isn't it?
Same here, Telefunken GZ34 has lasted forever in my 67 DR.
Not sure if was original or not, but I wouldn't be surprised if it was the original one.

[phantomman]

I always had good luck with Mullard, Telefunken, Amperex, and Philips rectifier tubes (the originals from "back in the day", now commonly referred to as "NOS" and commanding arms, legs, and first-born children to purchase). Frankly I don't put much stock in GTs, JJs, SovTeks, TADs, or any other of the trendy new brands. But of course I freely admit to bein' an iconoclast......

HTH

[Don]

A 5AR4 is a GZ34.

The Mullard in my VR was in the amp when I bought it about 20 years ago!

I have a spare solid state rectifier as well.

I have to bias the amp no matter what I do.

After I get the amp up and running an find that there are no other hidden expenses I will put a GZ34 in it and re-bias it.

[Totally bored]

Originally Posted by Cygnus X1

A 5R4 is a GZ34, isn't it?

Nope.


From the Link :

1) Solid State Rectifier (NOT Weber Copper caps)
2) 5AR4/GZ34
3) GZ37 (3 amp filament current)
4) 5V4G/A (Possibly lower if plate current of the power tubes is high enough)
5) 5U4/G/A/B (3 amp filament current)
6) 5R4G/A/B
7) 5Y3G/B

[Totally bored]

Originally Posted by phantomman

I always had good luck with Mullard, Telefunken, Amperex, and Philips rectifier tubes (the originals from "back in the day", now commonly referred to as "NOS" and commanding arms, legs, and first-born children to purchase). Frankly I don't put much stock in GTs, JJs, SovTeks, TADs, or any other of the trendy new brands. But of course I freely admit to bein' an iconoclast......

HTH

Yeah I here ya. They wanted $125 for a Mullard and $15 for a JJ so I got 2.

I figured that the extra one would also be good for diagnosing amps in the future. Didn't want to throw my Mullard in my DRRI to see why I was blowing a fuse if you know what I mean ?

[Cygnus X1]

Originally Posted by Totally bored

Nope.



2) 5AR4/GZ34

6) 5R4G/A/B

Clipped.
OK, I thought maybe someone sold a vowel and left out the "A".
Thank you for the clarification.

[Gris]

Buy a Weber copper cap GZ34 for $20 for it. less worry than a real tube. sounds jst as good (i have both Mullard and copper cap too).

[Don]

Originally Posted by Gris

Buy a Weber copper cap GZ34 for $20 for it. less worry than a real tube. sounds jst as good (i have both Mullard and copper cap too).

Good idea! I hadn't thought of that!

[Gris]

I always carry a spare in my bag - it's not glass, so I just throw it in there no worries... :-)