Memphis Tone circuit

[If6Was9]

I purchased a new (2014) ES-335 a month ago. I never heard of the "Memphis Tone Circuit" before I got this guitar. I have been scouring the internet for information but have not been able to find anything that is concrete. No wiring diagrams or schematics anywhere. Some say that it is '50's wiring and some say it is just a treble bleed.

Well my observation is that it seems to be both.

When I turn down the volume, the sound becomes very thin and bright especially past 5 on the dial. This reminds me of the old school treble bleed with just a cap across the 2 lugs of the volume pot without a resistor. Then if you start to turn down the tone control there is a big drop in volume. I would have to turn up the volume a little when I turn down the tone, to compensate for volume drop. This reminds me of '50's wiring (which is the main reason that I had switched my Lester back to modern after trying out '50's wiring for a couple of months).

When I had a guitar back in the early 80’s that had a treble bleed, I do not remember it affecting the tone that way and when I tried ‘50’s wiring a couple years back, I remember it retaining the clarity as you turn down the volume, but I do not remember the sound becoming so thin and bright.
So, my question is does anyone here know anything more about the "Memphis Tone Circuit"?

Thanks,

 

[beaubrummels]

Re: Memphis Tone circuit

Memphis Tone Circuit
http://www2.gibson.com/News-Lifestyle/Features/en-us/volume-control-0723-2011.aspx

"Many guitars darken up a little when you turn them down because the loss of highs is emphasized more than the overall volume cut. Some players work with this, using it to mellow out their tone, then brighten it up at full volume for solos that really cut through. Other players find it a little bit of a problem with the “turn it down” technique. That’s why Gibson’s ES-339 carries its special Memphis Tone Circuit, specifically designed to retain the guitar’s full tone when turned down. But you can also achieve this on your own guitar with one of the simplest modifications you can perform. The addition of a small .001uF capacitor between the input terminal on each pickup’s volume potentiometer (the terminal to which the pickup’s own hot lead, or the hot lead from the switch, is connected) and the middle terminal on the pot allows some of the highs to pass through into the signal even when the volume control is turned down. Some guitar techs also like to add a small 150k to 300k ohm resistor in the same position so some lows pass through along with the highs, so the tone doesn’t thin out too much. If you are experienced with a soldering iron and guitar wiring (if you perform your own pickup swaps, for example) you will probably be able to do this yourself."

Additional info: Memphis Tones on Historics
http://www2.gibson.com/News-Lifesty...phis-Science-of-Volume-and-Tone-Controls.aspx

"The Memphis division found that with their magnetic pickup and wiring configurations, 500,000 ohms for the volume and tone pots is a “dividing line” for loading. While lower values can affect the sound, the loading from higher values is so slight most musicians won’t notice it. So, to insure that the pots provide minimum loading, Memphis specifies a custom-made 550,000 ohm pot. But wait…there’s more. You might think the story would end there, but Memphis takes an additional step by measuring each pot’s resistance. This not only provides quality control to verify all pots are within spec, but Memphis classifies each pot as having a resistance more toward the higher or lower end of the specified range of values. . . . Those higher resistances are used with the neck pickup, as that’s where you want maximum high frequency response to reduce muddiness. Those with lower resistances team up with the bridge pickup, which “sands off” the edge ever so slightly."

...also, I saw information around that for certain models they used Audio taper for volume instead of Linear, and the newer ones have the "woman tone" cap recipe of .022mf bridge / .015mf neck, which would be brighter (in the neck anyway), but I don't believe yours has this.

 

[Funkfingers]

Re: Memphis Tone circuit

The question that you have to ask yourself is this.

Is the Gibson Memphis Tone Circuit a staggering advance in guitar technology for the benefit of the working musician OR did Gibson mis-order a shedload of 550k pots and have to hurriedly invent an inexpensive solution?

(Many twenty first century Gibson electric guitars turn out to have A440k volume pots.)

Why has it taken Gibson sixty years to discover this MTC phenomenon? :scratchch

 

[If6Was9]

Re: Memphis Tone circuit

Memphis Tone Circuit
http://www2.gibson.com/News-Lifestyle/Features/en-us/volume-control-0723-2011.aspx


Additional info: Memphis Tones on Historics
http://www2.gibson.com/News-Lifesty...phis-Science-of-Volume-and-Tone-Controls.aspx


...also, I saw information around that for certain models they used Audio taper for volume instead of Linear, and the newer ones have the "woman tone" cap recipe of .022mf bridge / .015mf neck, which would be brighter (in the neck anyway), but I don't believe yours has this.

Thank you for the links. I guess my Google search skills aren't that great. I did read that the 2015 models have the "woman tone" caps. Some day i'll work up the courage to gut the controls and either rewire to modern or just scrap it and replace it all.