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What would be the noticeable effect of using a humbucker pickup magnet which had broken and has been glued back together? Thanks.

From an old post in an amp forum: ".... The engineers at SBE - who took over the "Orange Drops"............ The idea is to have the outer foil connect to the low impedance side of the circuit, thus - contrary to Gerald Weber's recommendation - the outer foil would go to the plate of say a 12AX7 (~62K//100K) instead of the cold side with the 1M grid resistor...." Just saying.

Hahaha. We better hide this thread so nobody sees it. 😂🤣😂

Have a good one @stokes. It's been fun. Take care.

I never said DC resistance. I've clearly said AC. The DC resistance is not important as the noise on the capacitor foil which you try to bleed off will be AC not DC. Let's put a fork in this one, it's done.

Nice. I took the school route, not a judgement. I graduated RCA Institute tech school in NYC in 1974 worked as a tech went to Stony Brook U in 1978 and after graduating as an ee worked as design, systems, and planning engineers until I retired at the end of 2019. The load resistor prevents the short circuit of the signal to ground. I had said it was the lower resistance point to ground not a short to ground.

Okay then, just two cranky old guys having a discussion. I studied tube circuits in school also. Do you agree that R load is << than R grid leak? Do you agree that the filter cap is almost a short for ac signals such as noise? Then how can the point I labeled "outside foil" not be closer to ground than the other end of the coupling cap?

You're just wrong, I don't know how else to explain it to you. Anyway, the foil in the guitar cap goes to the end away from the amp. A typical amp has an input impedance of about 1M which is much higher than the pickup and tone pots.

The paths to ground are entirely different. One is through the filter caps and the other is through the power supply and associated resistors. Filter caps have a much lower impedance. Would you really use a high impedance voltage source to feed a low impedance load? A preamp has a low output impedance and a poweramp has a high input impedance. Same reasoning. This is basic.

If the 250VDChas a filter cap to ground and the 1 VDC doesn't then the 250VDC is closer to AC ground.

Do not get confused by the DC circuitry. The AC signal output point is between the plate and the plate load resistor. At that point, from an ac perspective, the resistor and the tube are in parallel with the non-plate end of the load resistor tied effectively to the cathode, or the cathode resistor if there is one. Draw it out from an AC viewpoint.

My understanding is that the plate is connected to V+ through a 100K ohm which is in parallel to the effective AC impedance of the tube from plate to cathode. At V+ the filter caps are a virtual AC short to ground which makes the V+ node an equivalent AC ground. So the AC impedance to ground at the plate is less than 100K ohms which is lower than the impedance to ground of the following grid circuit.

I agree with connection to the lowest impedance connection to ground but wouldn't the plate side, through the power supply, be the lowest AC signal connection to ground in an amp? Thanks.

When wiring up a Les Paul per the 1950s configuration, which connection should be the outside foil end of the tone capacitor? Thanks

Terry Mcinturff of Terry C. Mcinturff Guitars refretted my 1970 LP Custom years ago and it has been perfect ever since. It just needs to be done correctly, like everything else.

I guess the early Titans used the same knobs. Thanks, S

Looking for 3 replacement knobs for a '63 Mercury 1 amp that my son just bought from Wilco's Loft. Anyone have any ideas where I might find them. Thanks