I'm not exactly sure about how a blend pot works; as far as I know it's like 2 ordinary pots that work in opposite directions, so I was wondering if the pot itself has any noticeable effect on the tone. Eg, when the blend pot is turned all the way to the bridge pickup, will it sound exactly the same as if I used a switch to select the bridge pickup, or will the fact that there is an extra pot in the circuit affect it?
Does a blend pot affect tone?
- Thread starter Jeremiah
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Wasn't me, but yes it will darken the tone a little bit.... except... if you use a blend pot only, and no volume pot. The better way of doing it, is to wire two volume pots like they do on a jazz bass... so you can use either, or both. If you also use some bypass caps for the treble - about 47pf or so, then you'll be pretty much good for tone, within the capability of passives. The 47pf is subject to needing tweakage, depending on the the pickups used.
drewfx
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When compared to a switch, it adds another (resistive) path to ground, so it can darken things due to additional loading. If you do the treble bypass thing CB mentioned, and/or use higher value pots all around, you can compensate for this somewhat.
I suppose if you didn't need the other pickup 100% off when turned all the way to one side, you could wire it to provide more resistance to ground/less loading, but I haven't tried it like that.
I suppose if you didn't need the other pickup 100% off when turned all the way to one side, you could wire it to provide more resistance to ground/less loading, but I haven't tried it like that.
Unwound G
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On a two pickup guitar, I have taken a wire from each pickup at the toggle switch and solder each to the two furthest most lugs of a 1 Meg pot. It became a panning pot which blends the two pickups by regulating the signal from each very much like a Left/right balance control in an audio player. This way, no tone was lost since grounding does not come into the picture.
Unwound G said:
Hmmm. Its not only the ground path that sucks the highs, but the series resistance as well. If you put some series resistance in a signal path, it does not act like a pure resistor, but rather, it variably acts on different frequency like an inductor does. That means... you're going to cut highs when the series resistance is greater. With the 1m pot, balanced out, you've got 500k in series, nothing to sneeze at..at..att.. attchoo!
Unwound G
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=CB= said:
Need a tissue :laughing7: :laughing7: :laughing7: ?
I guess that is why the toggle switch is still important for the middle postion. Oh.......my mistake, one of the leads from a pickup should to soldered to the middle lug which is connected to the wiper. The blending will take effect as the wiper moves closer to the end of the carbon track where the other pickup is connected.
drewfx
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=CB= said:
I was thinking just wiring a 500k blend pot with no ground connections would work better - you'd get no additional loading when in the middle, and 0-500k series resistance on one pickup when turned to one side or the other. And never any additional loading on the louder pickup.
You would kill the highs faster than the lows on the attenuated pickup though, and the "off" pickup couldn't be 100% off electrically, but in practice I would think 500k would kill the output of any pickup.
Or you could make the ground connections with resistors of, maybe something like 220k-470k to reduce the loading and frequency variance a bit. Have never tried it though...
No, the 500k in straight resistance wont kill the output of a pickup... what it will do is add a huge amount of hum, because it isolates the normally low resistance (impedance really...) to ground by the value of the pickup, leaving what is in essence a "floating" coil.
Any blend worth its carbon wafer, uses a dual pot, linear taper, with each pickup having a ground reference through the pot.
Any blend worth its carbon wafer, uses a dual pot, linear taper, with each pickup having a ground reference through the pot.
drewfx
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Sorry, but I don't quite follow where my thinking is going wrong here.
Don't you still always have a low impedance connection to ground through the 2nd pickup?
Isn't it still a voltage divider due to all the other paths to ground in the circuit (though perhaps a more inductive one)?
How is adding only 500k of series resistance so much worse than adding infinite series resistance with a switch? Doesn't a switch also leave a "floating" coil?
Certainly not saying you're wrong. My brain just sometimes misses obvious stuff, and I don't quite get it...
Don't you still always have a low impedance connection to ground through the 2nd pickup?
Isn't it still a voltage divider due to all the other paths to ground in the circuit (though perhaps a more inductive one)?
How is adding only 500k of series resistance so much worse than adding infinite series resistance with a switch? Doesn't a switch also leave a "floating" coil?
Certainly not saying you're wrong. My brain just sometimes misses obvious stuff, and I don't quite get it...
Hey guys. I'm using a dual 500k blend pot in my WGD for my dimarzio's. Honestly there is no blending whatsoever. I wired it up using a schematic from the stewmac website. What I get is full on of either pickup at either end of the pot's travel and at the detent I get both pickups, full on. I think I am going to replace the blender with a concentric pot for dual volumes. I thought the blend was a good idea, but it turns out that I didn't get the intended results. I bought the pot from the local fender dealer and all he knew was it was somehow used for Clapton's "Woman" tone, I mean this guy couldn't stop repeating about the damn 'Woman" tone. I knew what I wanted and it was a cts pot, and it was funny that he didn't know what I wanted after I explained it to him. I really don't even know what this 'woman tone' he was referring to is or was. And I listen to a lot of slowhand, maybe someone wants to tell me where I can find an example of this said woman tone?
Anyway, I'm not totally sold on the whole blend pot setup anymore. I was all about it when I built the guitar, but after playing it now for a year, not so much. That and I have a concentric tone setup on the guitar, I could easily match that setup for the volumes.
Anyway, I'm not totally sold on the whole blend pot setup anymore. I was all about it when I built the guitar, but after playing it now for a year, not so much. That and I have a concentric tone setup on the guitar, I could easily match that setup for the volumes.
drewfx
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The "woman tone" basically means using the neck PU and turning down the tone control like EC's stuff with Cream. It has nothing to do with a blend pot AFAIK.
Did you wire yours like this?:
http://www.stewmac.com/shop/Electronics,_pickups/Potentiometers/Blend_Pots.html?tab=Instructions#details
Did you wire yours like this?:
http://www.stewmac.com/shop/Electronics,_pickups/Potentiometers/Blend_Pots.html?tab=Instructions#details
drewfx said:
Yep that was the wiring I used.
And didn't EC use a gibby back in the cream days? I don't know WTF dude was trying to sell me. I'm really glad I knew what I was buying. Are you talking about like the 'strange brew' kind of sound? I have a bunch of cream music here too (I have most of EC's recorded stuff in all of his different projects) and still I hear about this famed woman tone and have no freakin idea what it sounds like. Honestly I wouldn't know what to play for someone if they asked me to hear the 'woman' tone. So would you mind giving me a specific example so I can listen to it? I hadn't thought of that frustration till I remembered buying that damn blender pot.
I really know that it has nothing to do with a pot this woman tone, but I thought it was funny this guy that sells and repairs guitars for a living had no idea how or what to do with this blend pot other than it was for EC's 'woman' tone. Here I sit unemployed, with more guitar knowledge in my little toe and he is the guitar guru around here. Funny how the world works.
drewfx
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http://www.gibson.com/en-us/Lifestyle/Features/how-to-get-claptons-classic/
Those wirings should work for a blend pot. What happens when you leave the center detent? Does the 2nd PU drop out immediately or stay at the same volume and only drop out when you get to the end of the pot's travel?
If you disconect the second PU, the remaining PU should be 100%-on for one half (up to the detent), and gradually turn down on the other half. If that doesn't happen for each PU on its own, something is wrong with either the pot or the wiring.
Those wirings should work for a blend pot. What happens when you leave the center detent? Does the 2nd PU drop out immediately or stay at the same volume and only drop out when you get to the end of the pot's travel?
If you disconect the second PU, the remaining PU should be 100%-on for one half (up to the detent), and gradually turn down on the other half. If that doesn't happen for each PU on its own, something is wrong with either the pot or the wiring.
drewfx said:
I get the drop of one pickup when I leave the center. I have tried wiring it both ways thinking that I wired it backwards or something. I can't 'blend' meaning I can't do 3/4 bridge PU and 1/4 neck PU and vice versa like I originally wanted for the guitar. Oh well it' no biggie for me really, with the T-bridge in the guitar and both PU's I don't really feel the need to blend them this way anymore. I am, however, going to switch out the blender pot for a stacked pot so I have independent volume and tone controls for both pickups. I really like the stacked tone in the guitar, so I think I'm gonna match it for the volumes. I think I will switch the layout of the pots, right now I have the tone's on top of each other, when I get around to ordering another stacked pot, I think I will do volume over tone for both pickups.
Maybe dude was right, maybe he wasn't blowing smoke up my ass, maybe he had some sort of special extreme duty highly specialized dual blend pot from the space shuttle that happens to work for the woman tone!!! I never wanted the damn woman tone to begin with, just a blend pot!!! And I didn't even get one that works right anyhow, oh well another $20 bill pissed away..... not that i'm concerned with the money, hell sometime I'll build another guitar just to use that blend pot for something....... Maybe I'll build a woman tone guitar and sell it to the shop!!!
Actually it's funny now that I think about it, my multi tester told me that this pot didn't have a very smooth taper............ And talk about a detent!!! I honestly think they pulled this pot out of somebody's guitar, cleaned up the solder and bagged it up to sell again, you know so you could put the woman tone in your guitar!! Caveat Emptor
haven't read all the posts and i's sure it has been answered. it depends on how much resistance is shunting the signal. larger pots for the blend and the volume can be used to get the same effect. but in the middle blended position it will be slightly darker and quieter than a switch would be as you are driving through a good amount of resistance and the resistance to ground is much less. the darker sound can be combated by adding small capacitors from each pickup hot to the output. i cant quote numbers as i haven't experimented with this.
