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Post by wolf on Apr 10, 2008 10:06:26 GMT -5
Well as this graphic says, here are the typical volume and tone wirings: Now, here is an alternative method: I imagine the major disadvantage of the volume control's alternative wiring is the fact that it probably does nothing from the 10 mark to the 5 mark. As far as advantages I think that • it is slightly easier to wire • the solo switch is easier to wire. (Instead of a DPDT, you just need an SPST). • OR if you don't use a solo switch, couldn't a "full on" volume control now be feasible just as there are full on tone controls? I would think to get a smoother volume change, the pot value would have to be a lot lower than 500K or even 250K. So, lets' suppose a 25K pot were used. Would that provide a smooth volume change? Also, since we would use (or make) a "full on" volume control, would there be a smooth volume change between position number 9 and 10? I was just wondering. All comments are welcome. Thanks.
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Post by newey on Apr 10, 2008 10:16:25 GMT -5
Wolf-
I would think so, but at a tonal price- wouldn't this make to pickups sound pretty "muddy"? How about 100K as a compromise value?
Also, you would just be lowering the V pot value, right, not both?
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Post by wolf on Apr 10, 2008 10:50:37 GMT -5
newey Correct. I would just be lowering the the volume control resistance. The tone control resistance would stay the same. As far as 100K, if that would work fine. Now that I think of it, a treble bleed capacitor might work but then that cuts down on the simplicity of the wiring.
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Post by sumgai on Apr 10, 2008 15:58:09 GMT -5
wolf, Geez man, we buy you books and send you to school, and whaddya do......... Let me posit this to you: If a current controller (a rheostat) could do the job correctly, don't you think that everybody and his uncle would've gone that way by now? What you just did was remove the voltage divider (the potentiometer), which lets the amp endure a small amount of impedance change over the range of full on to full off. A current controller can't do that, hence the amp reacts badly to the input, and the pot shows little if any control over the signal level. Long story short, to make things simple in an optional area, you've sunk the boat in a critically necessary area of the design. That's what's known in the trade as "real bad ju-ju". My advice: don't underestimate folks and their skills. Just because someone doesn't understand how a simple lightbulb circuit works doesn't mean the they can't follow instructions, and connect wires to a DPDT switch with competence. I beg of you, give 'em a chance, and when they're finished, they won't be looking for a large blunt instrument with which to come looking for the guy who ruined their tone! </end sermon> HTH sumgai
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Post by ChrisK on Apr 10, 2008 17:36:23 GMT -5
Well, you now have the ALL-CUT tone control in parallel with the HI-CUT tone control. Oh, ok, it's not really a volume control but a volume/tone control since it shunts (loads) the pickup(s) and reduces their harmonic content first and then their overall level. It first cuts the highs and then the all's. It really is a progressive ALL-CUT tone control (until there's no tone to further cut). One can forget all about the treble (anti)bleed circuit. One should start at least at 250K. I'd use 500K, but then I wouldn't do this. 25K is already in the basement of just sines. However, if'n one likes it..............
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Post by JohnH on Apr 10, 2008 22:54:22 GMT -5
I'm also thinking I'll stick with normal wiring for now. But in the case of an idea by such an esteemed member as Wolf, I think it merits a run through 5Spice to explore it, which is easy to do, and I'll give it a run in a day or so.
John
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Post by wolf on Apr 11, 2008 2:43:27 GMT -5
Well sumgai and ChisK I appreciate the constructive criticism. I figured my idea might incur some negative comments but this is GuitarNuts2 and is a place to try out new ideas.
JohnH I appreciate the fact that you are going to run the circuit through a computer simulation and see what happens. Also thanks for calling me an "esteemed member".
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Post by JohnH on Apr 11, 2008 5:42:52 GMT -5
OK, well here it is, in a circuit representing a PAF style humbucker, of 8k dc resistance and 3.8H inductance. Here's the schematic: Theres equivalent to about a 10' cord to an amp input included. R5 and C4 are the normal tone control, set at max. R2 is the 'alternative' volume control. Now let's turn the volume down, first in 9 steps from 500k (100%) to 50k (10%): And here it is from 50k down to 5k ( 1%): Well, as you can see, volume at the lower frequencies (below about 500hz) isn't much affected until it's almost at zero. Instead, most of the cut is at high frequencies A 100k log pot would probably be needed to get much overall volume control action out of it, for which a setting of 2 1/2 out of 10 would be about 5k, or 1% of 500k, being the lowest line on the graphs above. But when using such a control, the most apparent effect would be the cut of high frequencies So there we go! Its good to test these things. I do however, find this type of 2-lug 'rheostat' volume reduction to be very effective when blending away one coil when two coils or pickups are in series. By acting mainly on the upper harmonics of one coil, leaving the other unaffected, it changes the character of the sound without turning muddy. cheers John
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Post by ChrisK on Apr 11, 2008 12:07:58 GMT -5
Yep. I'm fond of it too as it's the only meaningful way to do a series blend. When in parallel, pickups get blended in by increasing their weight in/to the average. When in series, they get blended out by being increasingly bypassed. Series_Parallel Blend Pot w/ DPDT switch
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Post by sumgai on Apr 11, 2008 15:01:30 GMT -5
Thanks, John.
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Post by wolf on Apr 12, 2008 3:16:25 GMT -5
John H Thanks for running that through the computer. Okay, so maybe it isn't such a good idea. I guess I'll confine myself to switch circuits.
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Post by lpf3 on Apr 12, 2008 11:39:44 GMT -5
Wolf , Thanks, I needed The drawing of the typical master volume & tone control you posted here. Looks like one man's question is another man's answer Good luck with your alternative - lpf3
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