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Amp Stuff => Archives of favorite topics => Topic started by: EL34 on June 15, 2005, 07:53:10 am
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> 5E3 with Choke Voltage Chart
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bnwitt
Senior tube assistant
Posts: 255
(1/25/04 2:48 pm)
24.30.114.166
Reply | Edit | Del All 5E3 with Choke Voltage Chart
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I finally had time to record all voltages on a 5E3 with a choke in place of the 5kohm resistor:
5E3 Tweed Deluxe Voltage Chart
First Voltage drop device used: __X___Choke ____Resistor
PIN V1 V2 V3 V4 V5
12AY7 12AX7 6V6GT 6V6GT 5Y3GT
1 137 183.2 23.2 23.2
2 0 0.5 6.71AC 6.71AC 5.32AC
3 1.9 1.31 349.7 349.7
4 6.7 AC 6.7AC 357.8 357.4 697AC
5 6.7AC 6.7AC 17.7 18
6 134 223.4 697AC
7 0.1 16 6.71AC 6.71 AC
8 1.97 47 23.2 23.2 5.32AC
9 6.7AC 6.7 AC
Board B+#1 364 at standby switch
Board B+#2 361.9 at choke output
Board B+#3 268.2 at 22kohm resistor
Power in m.a. at V3 and V4 43.5 47.5
Edited by: bnwitt at: 1/25/04 2:54 pm
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What kind of benefits would the bigger choke(125C1A) bring when comparing to the smaller one(125C3A)??? [smiley=devil.gif]
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well, i'm really sorry but i still don't own any of them....maybe EL34 can gives it's numbers....whether he has time to do it.... [smiley=samurai.gif]
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Chokes store current and resist current changes.
Filter caps store voltage.
When there is a demand on the power supply like when you hit a big fat open E string, the power supply needs power. The combination of filter caps and choke supply the power supply with extra umpf!
A bigger choke would give you a smoother resonse.
125C1A is bigger than 125C3A but I have no idea how to put that into a number value.
I never pretend to know exactly what the exact results will be. You will always end up with egg on your face. (whatever that wise old saying means)
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I have the 125C3A and when i measured it I got a little over 100ohms. Can't remember exactly.
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The standard 125C3a choke (which was used on the above amp's voltage chart) has a dc resistance of about 110 ohms and 2.8 henries. The 125C1a (super reverb choke) has a dc resistance of about 230 ohms and 4.0 henries. I hope that helps.
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My first Stout was built with the smaller choke, and the JJ 40 20 20 20cap can, and GZ 34 rectifier. It sounded incredibly good much better than I ever had hoped for except for one small niggle... when pushed hard occasionally it would give the impression that it almost stuttered for a Split Second as el34 mentioned above.
I built a second Stout this time with more filtration, 2x33uf, 33, 33, & 20/10 switchable) & the larger choke.
Didn't like it anywhere near as much it seemed too stiff and lifeless and it lost that raunch and grind that the original had and it was too loud I didn't want to put it on 10 .
The same thing happened with my 5e3. It started with 47 , 47, 33 (I think) . It has that high voltage mojotone power transformer that will support 6l6s, but I never liked it until I switched out the caps for ones that were closer to 16u , and 8 or 10 @ 1st pre-amp.
I know there are all kinds of things that effect the end results but my thought towards my next building of those style amps is I think I'll try the larger Choke On the Stout with the JJ caps and I may try the small choke on the Tweed Deluxe, but imho over filtration kills them so maybe chokes will give them life