1 meg pots and TB Plus pickups

[exiledarchangel]

I am not an expert, but I really don't find anything interesting on 1M pots. Maybe if you are a dog, or a bat, you will notice some extra brightness, but the taper of the pot is not good at all. If you are a guy that uses pots a lot, its better to bring back your treble using some other methods, like installing an onboard buffer in your bass.

[georgestrings]

..As bright as the pickup and tone pot will allow is more correct. Correct me if this is not the case with TB+ circuits, but with the tone pot on 10 you bleed the trebles through whatever resistance your pot value is to ground via the tone cap. Not that I'd ever bother changing the value to 1M, because as you said the pot will have more like an on/off function and have a lot of useless travel, but it answers georgestrings' question.

Sure, with a tone pot, that's definitely true - but, what about using a 1 meg as a volume pot with a TB Plus??? That's what I'm really asking about - and so far, no one has spoken up that has actually tried it, that I'm aware of...


    - georgestrings

[georgestrings]

I am not an expert, but I really don't find anything interesting on 1M pots. Maybe if you are a dog, or a bat, you will notice some extra brightness, but the taper of the pot is not good at all. If you are a guy that uses pots a lot, its better to bring back your treble using some other methods, like installing an onboard buffer in your bass.

I really don't want to add an active circuit, I just want to "take the blanket off" these pickups, so to speak - while retaining the ability to blend them, or roll them off altogether in some situations(on stage or at rehearsal)

At any rate, it doesn't look like anyone here has ever actually tried a 1 meg volume pot with a TB Plus pickup, so I might end up being the guinea pig... I'll be sure to post the results if I end up trying this, though...


    - georgestrings

[amptech]

I really don't want to add an active circuit, I just want to "take the blanket off" these pickups, so to speak - while retaining the ability to blend them, or roll them off altogether in some situations(on stage or at rehearsal)

If you feel you want to take off a blanket, the pot trick (1M or no load) will not do that - not that much effect. Sounds like different pickups or stainless steel strings is more likely to have that much effect.

At any rate, it doesn't look like anyone here has ever actually tried a 1 meg volume pot with a TB Plus pickup, so I might end up being the guinea pig... I'll be sure to post the results if I end up trying this, though...

I have installed many 1M pots and a couple of no load pots for guitar players. There is a lot of talk now about how much you can change or 'sculpture' your sound by tinkering with tone pots and cap values. I personally don't think it is worth it, I just tried to explain what happens. Other than a direct out option on one of my own EB3's, I usually end up with stock wiring. Other than fender jazzmasters and some other, 1M pots aren't much used and for good reasons.

[Granny Gremlin]

One thing that has been ignored here is the vol pot and the treble bleed there.  Quite sure that the corner freq of the bleed is well above what bass players mostly care about but maybe not. Treble bleed only happens when volume is not at full - when at full the resistance of the pot is at it's minimum so there is insignificant load and no bleed.  You can compensate for the treble bleed with a simple cap and resistor across the pot (google treble bleed mod). Again, trying the pup straight to jack will tell you what the maximum difference you could possibly make is.  Start there, see if that gives you something you want, and then come back and see how you can mod the circuit to get closer to that tone.  As people are saying, it's really a matter of a few degrees and not like some heavy blanket has been lifted.  Sometimes, that's just enough to make a dude happy, and depending on the pups it can make slightly more or less difference.

[georgestrings]

OK, thanks, everyone - I appreciate everyone's input...


    - georgestrings

[Dave W]

FWIW, the '70s Tele Bass II (big humbucker edition) had 1meg volume and tone pots. I had a '77. Turning down the volume pot went to instant mud.

[Granny Gremlin]

Hmmmn, I might have to get me one of those ;P

[slinkp]

Other than fender jazzmasters and some other, 1M pots aren't much used and for good reasons.

Now you've got me curious. What's special about Jazzmasters that makes 1M pots appropriate?

I've never actually played a jazzmaster, but really like the sounds other people get from them, have a fantasy of owning one someday if/when I can justify a 6-string purchase.

[amptech]

Now you've got me curious. What's special about Jazzmasters that makes 1M pots appropriate?

I've never actually played a jazzmaster, but really like the sounds other people get from them, have a fantasy of owning one someday if/when I can justify a 6-string purchase.

I replicated a couple of 58-64 era pickups last summer, for a guy who built a jazzmaster.  Last time I spoke to him, he still had not got around to the electronics - so I might have to put everything together

I could be wrong here (haven't got the schematics here) but the jazzmaster have a circuit with volume and tone that works on the neck pickup only, in addition to the main circuit. So the two 1M volume pots in paralell will make the reistive load 500K in total, at least for the neck pickup. I think they used linear taper pots too.

[Granny Gremlin]

The 'lead' channel which bypasses the rest of the controls when the 'rhythm switch" is engaged has a 1 Meg linear volume pot but the tone pot is 50K linear (the thumbwheels on the upper horn).  Great guitar, but most people hate that part of the circuit and remove it (confusing and those thumbwheel pots tend to die a lot; flimsy and until recently, a bear to find replacements for).  The stock controls are both 1 meg regular size pots; volume linear, tone logarithmic.

Since only one set of control pots is in circuit at any time, I'm not sure the 1M + 1M in parallel = 500K thing is the reason.  Moreso I think it's to get all the treble that's possible out of the pups - they are known for that sound.  Don;t know much about what makes the pups unique but it could also be something there too (like their DCR that makes 1 Meg pots work better; not sure)

I've had to work on a few of them since it's what most of the indie kids use.  First jam of the latest band I'm in had all 3 guitards show up with Jazzmasters or variants.

[amptech]

Don;t know much about what makes the pups unique but it could also be something there too (like their DCR that makes 1 Meg pots work better; not sure)

I think they have about the same DCR as a P90. The bobbin is really very much the same as a P90, but is forbon instead of plastic. I guess that the wire being wound directly around a short rod magnet makes them sound more fenderish than P90's. 

[Alanko]

No amount of passive circuitry will add elements back to your tone that weren't there in the first place.

[georgestrings]

No amount of passive circuitry will add elements back to your tone that weren't there in the first place.

No one is claiming that it will - however, it is a fact that different passive circuits will affect what passes thru them... Again, why do you think that 250k pots are typically used with single coil pups, while 500k are typically used with humbuckers??? Surely, you don't think that's just a coincidence, do you??


   - georgestrings

[amptech]

No amount of passive circuitry will add elements back to your tone that weren't there in the first place.

No, but it can take it away, and that is what georgestrings is trying to compensate for if I understand him right.