The values would be .01uf and .1uf. But the low end rolloff of the stock caps is @ 20Hz and under so you won't get any return on your investment there. Allowing very low Hz through the circuit could actually contribute to instability. Just stay close to the stock values. Caps are cheap. You might even try going higher up the rolloff point by putting in some even smaller caps to take it to 40 -50Hz, for kicks. A kick drum has prominant lowest frequencies around 80Hz so unless you have some source material from a synth or something that really produces low- low rumbles, you'll never hear the rolloff point as an issue. Beware imagination without measurement.
Use a small 6.3V transformer (under an amp) hooked up in reverse to the 7V winding to get 120V for the CS supply.
lawdog,
Are you really sure you want to keep it stock? A $10 AnTek AN-0130 will take care of the C- supply "El Cheapo" needs. Being toroidal, it neither interferes with other magnetics nor is it interfered with by other magnetics, to a significant degree. 😀 A simple piece of sheet aluminum is what you fabricate to make a bracket for the toroid.
BTW, EL84/6BQ5s can be used in an "El Cheapo". Contact Jim McShane for the RC bias network change needed. The EL84 is good triode wired, but the 6V6 family is somewhat better.
Are you really sure you want to keep it stock? A $10 AnTek AN-0130 will take care of the C- supply "El Cheapo" needs. Being toroidal, it neither interferes with other magnetics nor is it interfered with by other magnetics, to a significant degree. 😀 A simple piece of sheet aluminum is what you fabricate to make a bracket for the toroid.
BTW, EL84/6BQ5s can be used in an "El Cheapo". Contact Jim McShane for the RC bias network change needed. The EL84 is good triode wired, but the 6V6 family is somewhat better.
Will a B&K 465 tube tester test these Maggie tubes? I've got a chance of picking up one for next to nothing?
Yes, any tube tester is better than no tube tester. At the very least, it will give you a go/nogo.
Ok, I now have a B&K 465 tube tester....but none of the adapters will fit the 6V6 or 6BQ5 tubes. Does anyone know if there are other adapters I can buy that will allow these tubes to connect into the 465?
oops, that's a "TV picture tube tester" (CRT 'Cathode Ray Tube' Tester). It will not work with audio tubes. sorry for my bad advice.
I knew it said picture tubes...but I thought it might give a go/no go. I got it super cheap, so I am confident I can easily get more than I paid on "that site".
LD
Try a set of new tubes, first. You could do just one channel at a time as you get this going. A reasonably priced, good, tester will run more than $50. It will take some time to find one you can feel confident is OK at that price. You can get a set of new JJ EL84 for that. They are great tubes, high quality, non-Russian, non-Chinese. Save your originals for testing later and as backups. You certainly need one new 6EU7, too. So doing one channel at a time is good option for now.
If you can find a 9-pin test socket, or two, that would make it easier to check voltages while the amp operates. Very usefull.
Try a set of new tubes, first. You could do just one channel at a time as you get this going. A reasonably priced, good, tester will run more than $50. It will take some time to find one you can feel confident is OK at that price. You can get a set of new JJ EL84 for that. They are great tubes, high quality, non-Russian, non-Chinese. Save your originals for testing later and as backups. You certainly need one new 6EU7, too. So doing one channel at a time is good option for now.
If you can find a 9-pin test socket, or two, that would make it easier to check voltages while the amp operates. Very usefull.
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