Recent content by tommytomcat

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    Rectifier Sag..

    I think you're getting the screen grid and cathode/bias resistors mixed up. The cathode resistor hangs off of pin 8 of the power tube socket and the other end is connected to ground. The screen grid is on pin 4 and typically a 5F1 doesn't have a screen grid resistor. Just solder in a 2.2K 2...
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    Cathode Bias limitations?

    The weber PT is rated at 100mA of current. Which is enough for 6V6's and 6L6's. An EL34 will be OK if you keep an eye on how hot the transformer gets when you're playing through it. (EL34 is a 70mA tube) There's plenty heater current available too, you could build a 5E3 with that PT (2 6V6's...
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    5F6A scratchy volume and presence pots from 12 o'clock

    Capacitors block DC and pass AC. If a coupling cap is faulty/leaky/failing, it can let some DC pass. The coupling cap is connected directly to the volume pot input.
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    Tube subs for a SFSR ?

    Sam... no offense, but it looks like you know just enough to be dangerous and you should to apologize to James. A tube is like a valve, too much flow or too little can cause things in an amp to melt down or blow up. 6V6's and 6L6's require a pretty different negative voltage on the power tube...
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    Tube Recommendations for BFSR?

    FWIW. If you never play through the normal channel, don't put an expensive tube in V1. If it's something you do play though a lot, see below. Tung Sol 12AX7 RI or in V2 & V4. (v1) 12AT7's in V3 and V6...
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    12AZ7 in Super Reverb - Q

    V3 is the reverb tank driver tube. If you're happy with the way the reverb sounds now, I'd leave it as is. And there should be no worries. I think the 12AZ7 pulls slightly more heater current, but not enough to be a concern.
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    Rectifier Sag..

    If you've got a tube rectifier in the power supply, you've got a resistor in the power supply. Tube rectifiers provide a voltage drop along with rectification. I haven't tried this myself, but I've seen it posted that one can get some sag with a SE design by using a bigger screen grid...
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    So you know those 10" speakers THD is blowing out on ebay?

    I know this thread has been dead for several months, but it anyone runs across this who has been using these speakers..? Please report in and let me know how you like them. I bought 8 of these when they were on sale on ebay and am finally about to getting around to using a couple of them in a...
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    BF Fender: how to make vibrato channel more like normal channel

    Change the 6.8K resistor going to ground off the bass pot to 10K. Up the reverb ch coupling cap to .047uF from .022uF. Change the 100K slope resistor in the tone stack to 56K. Change the .001uF PI coupling cap to .002 or .003 up to .0047uf, to boost mid's overall. The normal channel has...
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    Need a bigger sounding 5e3... or JTM45

    CD.. Before spending a bunch of money. #1 what kind of guitars are you gigging with throught the 5E3. The stock circuit get's pretty mooshy and compressed with humbuckers. To tighten the amp up: GZ34 rectifier. Lower the bypass cap and resistor combo on V1 pins 3 & 8 to 1.5K/5uF in...
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    Crisis of Tone - Amp Attack and Pick Response

    (I just watched a utube demo of the verbovibe and it sounds pretty darn good to me!) The Verbovibe sounds/looks like a Fender Vibrolux.. AB763ish.. type amp. I think the other two amps you're describing are cathode follower driven tonestack amps.. al la .. 5F6A bassman, Marshall jtm 45, Vox...
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    tweed deluxe upgrades (tubes, speakers)

    The 5E3 circuit is very bassy/midrangy. It was designed around an alnico speaker with 1" and later a 1.25" voice coil.. The circuit was designed to get a big and balanced sound when paired with fender's low output single coils of the late 50's. In most cases modern speakers with 1.5" and...
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    2x10" Blonde Cab for my '62 Tremolux..Jensen P10Qs Harsh. Suggestions? (long)

    One thing to check, is to make sure the speakers are wired in phase. I once loaded a 2x10" cab with carvin and a weber.. trusted the 'red dots'.. and they were out of phase. Which means one is pushing out while the other is pushing back. It killed about 30% of the volume and the pushed tone...
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    1970 super reverb with Allen mods

    If I were in the market for one, I'd jump on this... But, if you're asking will this amp appreciate in value and you'll be able to sell it for $1500 in 6 mos. No, this is a player not an investment... but you should always be able to sell it for close to $850-900.
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    2x10" Blonde Cab for my '62 Tremolux..Jensen P10Qs Harsh. Suggestions? (long)

    Is the 'old oxford' ceramic or alnico? If ceramic, are these the first alnico's you've played through?