Passive pot issues; treble attenuation slope

JazzCrazy

Inactive
Mar 25, 2018
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Joshua Tree
It really seems that my bad ground hum karma won't go away. I decided to gut my bass of its existing active/passive electronics (& Carvin pickups) get a new luthier* & start anew. I bought two Bourne attenuation pots (only needed one) & one was bad right off the bat. The Bourne blend pot I got seem to cut out when I turn it in all the way in one direction. Brand new! I bought this brand because it's supposed to be reliable.

I have an unused toggle switch formerly used for active electronics I had removed. The present luthier asked me if I wanted to be able to switch back & forth between treble attenuation capacitors. The truth is that my attenuation slope's too radical (steep) & results in so much treble attenuation that turning down the treble equates to too much cut in volume. All my pots are 250k, & I believe the existing cap is .047 microfarads (or .47, whatever's the standard). Does going down in microfarad value (.022 or .033) mean a more gradual slope, or must the values go up? Yeah, I'll definitely take him up on the toggle switch thing.

*Because the new 5 string 7.4 ohm Fender Jazz pickups were too large to fit where the old (Carvin) blade pickups had been on my Squier DJAV, the new luthier had to route out bigger pickup cavities, & when the painters masking tape was removed in the cold weather, spots of polyurethane peeled off with the tape--literally leaving those spots gouged texturally about 1/32" or more--leaving the exposed black paint appearing navy blue. He claims he can fix it all (I don't know how) & that what he did electronically was just preliminary. (The new neck pickup doesn't sound at all, yet)
 
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Cap value does not change slope. It's a first order filter -3dB per octave in all cases. Cap value just moves the cutoff frequency up (smaller) or down (larger).

If it's first order -3db @ the elbow frequency, -6db an octave below, then I'm not exactly sure how increased attenuation effects the overall frequency response. As you engage the pot incrementslly somewhere you get values that increase to more than -3db, -6db and so forth, (or is that at maximum attdnuation?)

But thanks. The fact is that I perceive an attenuation in overall output might be because a low elbow frequency means vital mid-frequencies also get cut.