GZ34 used in AA1164 Princeton Reverb?

[Arctic_AK]

Good evening.


I am newbie building a Princeton Reverb and was curious of any thoughts, concerns or other advice on using a GZ34 tube? It sounds much too easy.


Thank you all for any advice and guidance!

[sluckey]

Just plug it in. It's that easy.

[Arctic_AK]

Thank you Sluckey, are there any swaps I should make to any of the other components?

[HotBluePlates]

Is this an existing amp? If so, what is your B+ and what are the filter cap voltage ratings?


If this is a planned build, there are no changes needed, just make sure your filter caps are rated for the maximum possible voltage output (safe choice = 1.414 * A.C. RMS Volts of the power transformer).

[Arctic_AK]

This is planned, early in the building stage however I have read advantages to use of the GZ34 tube.


I appreciate the insight and direction Hot Blue Plates and Sluckey!

[HotBluePlates]

I've owned a number of Princeton Reverbs; my first tube amp was a '67 blackface Princeton Reverb and used the 5U4GB indicated on the tube chart.


I tried a GZ34 in it. I don't think you'll notice a difference unless the amp is cranked near full-up. Make sure your power transformer has a 5v 3A winding, and you can use either tube as you see fit.

[jojokeo]

I've owned a number of Princeton Reverbs; my first tube amp was a '67 blackface Princeton Reverb and used the 5U4GB indicated on the tube chart.

I tried a GZ34 in it. I don't think you'll notice a difference unless the amp is cranked near full-up. Make sure your power transformer has a 5v 3A winding, and you can use either tube as you see fit.

If I'm not mistaken there were PRs that used a couple different rectos no? Some were listed differently on the tube chart and/or schems too I think? I believe they all spec'd the same PT so would that imply that all PRs had the 5V 3A winding on them?

[HotBluePlates]

I think so.


My '67 had "5U4GB" on the tube chart, and most of the schematics in our library say 5U4. But I know others have run into schematics with "GZ34" indicated (and I thought I'd seen those too, though I don't have my old schematic manual handy to verify what I remember).


Maybe they could all supply the 3A for the 5U4. It's easy enough with the chassis pulled to monitor the 6.3v winding to know that it's not dropping because too much current is pulled from the PT.


But since Arctic_AK is doing a new-build, he can know the specs of his new power transformer and which rectifier it's capable of supplying.

[Willabe]

My BFPR tube chart says, AA764, OC (March, 1965?) shows GZ34.

PT is stamped, 125P1B, 606-5-08 and OT is stamped, 125A10B, 606-4-45.

Dave Funk's book and Gerald Weber's books list the same PT/OT #'s for PR models AA1164 and B1270, also Princeton (no reverb) AA964 has same PT/OT #'s.


              Brad     
   

[jojokeo]

Thanks Brad that's what I remember - mostly just not all the numbers
They all should be rated the same then