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previous: rmike Re: 5E3 Filament circuit -- 4/12/2000 9:29 PM

Re: 5E3 clone finished:Observations

4/17/2000 3:34 PM
Troy	Re: 5E3 clone finished:Observations This past weekend I finished my first clone "kit", the 5E3 tweed Deluxe. I wanted to post this since Mike and I are using the same PT (Hammond 270EX). Well I was surprised to find that with a 5Y3 rectifier I was getting plate-cathode voltage of around 340vdc! I then installed a "real" 5AR4 with RCA 6V6's and get the following: 363Vdc plate-cathode voltage 30.5ma per 6V6 with a 330ohm Rk 123Vdc on the preamp plates of 12AY7 When I had the stock Rk of 250ohms, I was getting a plate current of 35-37ma per tube. As I recall reading in the past, stock 5E3's have a plate voltage of around 360. Would this mean that most stock 5E3's run the 6V6's way hot? If my math is correct, I'm at 11W per tube which I think is pushing it and that's with a 330ohmRk. BTW, I changed the 22uf cathode caps (split cathode design on Hoffman board)off of the 12AY7 to 1uf@pin3 and 10uf@pin8 (thanks Bruce!). How do I like it? Loads of fun!! With the 5AR4 and the AY7 it doesn't run out of headroom too fast, just right! Thanks to Doug @ Jenkins for the great 2-10" combo cab. Mike: if you want the squash of a 5Y3 then I may look for a beefier PT than the 270EX; I prefer the 5AR4 anyway. Troy

4/17/2000 3:34 PM

Troy

Re: 5E3 clone finished:Observations

This past weekend I finished my first clone "kit", the 5E3 tweed Deluxe. I wanted to post this since Mike and I are using the same PT (Hammond 270EX). Well I was surprised to find that with a 5Y3 rectifier I was getting plate-cathode voltage of around 340vdc! I then installed a "real" 5AR4 with RCA 6V6's and get the following:

363Vdc plate-cathode voltage
30.5ma per 6V6 with a 330ohm Rk
123Vdc on the preamp plates of 12AY7

When I had the stock Rk of 250ohms, I was getting a plate current of 35-37ma per tube. As I recall reading in the past, stock 5E3's have a plate voltage of around 360. Would this mean that most stock 5E3's run the 6V6's way hot? If my math is correct, I'm at 11W per tube which I think is pushing it and that's with a 330ohmRk. BTW, I changed the 22uf cathode caps (split cathode design on Hoffman board)off of the 12AY7 to 1uf@pin3 and 10uf@pin8 (thanks Bruce!).

How do I like it? Loads of fun!! With the 5AR4 and the AY7 it doesn't run out of headroom too fast, just right! Thanks to Doug @ Jenkins for the great 2-10" combo cab. Mike: if you want the squash of a 5Y3 then I may look for a beefier PT than the 270EX; I prefer the 5AR4 anyway.

Troy

Replies:

Bruce Use the 5AR4 with that tranny or SS... -- 4/18/2000 8:15 AM
Rebel420 What is the output wattage you are ... -- 4/18/2000 4:07 PM
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