Best blend pot 250k or 500k

[Ringhammer]

I rewrite all of my 2 pickup Fenders to be V/B/T. I just prefer one volume control. I was always using MN250K control pan pots. There is always a sharp tone change when I come of off center, say, toward to neck pickup, but then quickly the change in tone stabilizes as if the remainder of the sweep to one side of the pot is mostly useless. My guess is that a MN500K would make this abrupt change a little less, and give a bit more range in the sweep. Is this true? Would a 1 Meg pan pot be even more smooth?

 

[dwizum]

Changing the value won't really impact the sensation of how much travel creates how much difference in tone/volume. The "curve" is the same, regardless of the value. A higher value will impact the tone less (resulting in a brighter tone) but the change will be across the board.

If you want a different feel, in terms of the degree of change as you rotate the pot, you could try an AC taper blend pot (instead of MN). AC is essentially an audio pot combined with a reverse audio pot. They're harder to find, but Bourns, CTS, and Alpha all make them in common values.

 

[Ringhammer]

Any chance you have a P/N for a Bourns 250k and/or 500k AC?

 

[ex-tension]

I was always using MN250K control pan pots. There is always a sharp tone change when I come of off center, say, toward to neck pickup, but then quickly the change in tone stabilizes as if the remainder of the sweep to one side of the pot is mostly useless. My guess is that a MN500K would make this abrupt change a little less, and give a bit more range in the sweep. Is this true? Would a 1 Meg pan pot be even more smooth?

You might want to read about this subject:
Blend Pot Problems
Better pickup blending... what's the answer?
Ultimate No-load Ungrounded Blend Pot (Pics!)

 

[Ringhammer]

Ugh, so many options. I have gathered from reading the my thinking 500k were better was wrong, and even a 100k would be better than a 250k.

Not to worried about the ends of the sweep being truly straight to the pickup, I usually run both, but it is good to know in a PJ setup so you can have a try P-Bass when you dial out the bridge pickup. Maybe only one trace needs to be cut if you never dial in the bridge pickup only?

I think the answer for me is to find 250k audio taper (AC) solid shaft pots. Too bad I just bought 5 new 500k. That’s $30 bucks I won’t get back.

Now the search for the above mentioned AC250K pan pots. Any help on that. Maybe I should contact Bourns directly?

 

[Passinwind]

Ugh, so many options. I have gathered from reading the my thinking 500k were better was wrong, and even a 100k would be better than a 250k.

Not to worried about the ends of the sweep being truly straight to the pickup, I usually run both, but it is good to know in a PJ setup so you can have a try P-Bass when you dial out the bridge pickup. Maybe only one trace needs to be cut if you never dial in the bridge pickup only?

I think the answer for me is to find 250k audio taper (AC) solid shaft pots. Too bad I just bought 5 new 500k. That’s $30 bucks I won’t get back.

Now the search for the above mentioned AC250K pan pots. Any help on that. Maybe I should contact Bourns directly?

Blend Pots - Best Bass Gear

Despite the labeling on the Noll one, I think it'll do what you want. I have one here I can measure to verify.

 

[Passinwind]

Followup: The BBG info is incorrect, the Noll is actually 250KA/250KC as I thought, per the Noll website.

 

[sunbeast]

Any Blend pot in a passive system is gonna be kinda frustrating compared to dual volumes IMO simply because you are squeezing the sweeps of two entire pots into the sweep of one. I still vastly prefer an MN taper when using it though, and smaller value blend pots are going to be less abrupt (though darker tonally unless you compensate in your volume/tone controls).

I personally find AC-taper pots even worse as far as not being able to find my favored blends, as the center position of an AC pot is something like 85/85 or less depending on the pot you use so you totally lose the ability to dime one pickup while blending in another (which is the main way I blend pickups)- the only time either pickup is fully “on” is at the two extremes of the sweeps where one or the other pickup is fully soloed. An AC taper instead makes for a very odd degree of blends that don’t resemble in any way what a passive volume/volume user would generally use (apart from maybe the old stacked-knob Jazz basses, that always had a resistance mixer between the pickups). I find the tendency for half the sweep of an AC to be inaudible to be even more extreme to my ears than an MN. Still worth a try anyway I guess.

 

[Ringhammer]

Great, thanks so much. I think, from what I am reading, my best bet is still the MN, but my thinking that a 500K would be a gentler transition off center is wrong, and instead a 500k allows more bright tone? If this is all tru, then I can use this info in deciding if I want a brighter sounding bass (use 500k), or a warmer sounding bass (use 250k).

I am also thinking that a 500k audio taper for tone control pot is going to allow more range on that pot, so a smoother tone control. Am I wrong on this too?

 

[JeezyMcNuggles]

I rewrite all of my 2 pickup Fenders to be V/B/T. I just prefer one volume control. I was always using MN250K control pan pots. There is always a sharp tone change when I come of off center, say, toward to neck pickup, but then quickly the change in tone stabilizes as if the remainder of the sweep to one side of the pot is mostly useless. My guess is that a MN500K would make this abrupt change a little less, and give a bit more range in the sweep. Is this true? Would a 1 Meg pan pot be even more smooth?

No. There really isn't any sort of "blend" not anything noticeable at least. As soon as one pickups is not on full, the other one takes over. When both are on full, it phases and scoops out your mids. A blend pot won't change that one bit. It'll just make setting your pickup volume different. I'd say, it'd be easier to use the volume knob that way. Because, your blend would be at one spot, so you'd actually have control over your volume with consistency in pickups. Plus.

Keep the pot a 250k. Anything more just adds scratchy high end that sounds shrill.

 

[JeezyMcNuggles]

Great, thanks so much. I think, from what I am reading, my best bet is still the MN, but my thinking that a 500K would be a gentler transition off center is wrong, and instead a 500k allows more bright tone? If this is all tru, then I can use this info in deciding if I want a brighter sounding bass (use 500k), or a warmer sounding bass (use 250k).

I am also thinking that a 500k audio taper for tone control pot is going to allow more range on that pot, so a smoother tone control. Am I wrong on this too?

Yeah, no difference in "blend smoothness"

It's just a shrill high end. It's not exactly "brighter" That's why they put 250s in basses in the first place.

 

[sunbeast]

Great, thanks so much. I think, from what I am reading, my best bet is still the MN, but my thinking that a 500K would be a gentler transition off center is wrong, and instead a 500k allows more bright tone? If this is all tru, then I can use this info in deciding if I want a brighter sounding bass (use 500k), or a warmer sounding bass (use 250k).

I am also thinking that a 500k audio taper for tone control pot is going to allow more range on that pot, so a smoother tone control. Am I wrong on this too?

I think smaller value blend control compensated for by a very large value volume and/or tone control is the ideal for both blending and allowing the largest frequency spread (the total resistance to ground of the control circuit via volumes, tones and blends helps shape the top frequencies of the pickups attached).
A large value tone control may not have a “smoother” taper per se, as a large amount of the sweep is just affecting the loading of the circuit (more subtle change) vs the more dramatic change that the capacitor creates near the bottom of the sweep. So if you like to use darker tones, a larger value means you are squeezing those tones into a shorter portion of the sweep and it may be difficult to dial in the subtle shifts (similar to the large value Blend control). With a larger tone pot you do get all the tones from the smaller values plus more on top- as someone who mostly uses the brighter end of a tone control, a larger value gives me more to work with so I appreciate it! Audio taper is the norm for Tone controls and usually seems to work best.

 

[ex-tension]

I am also thinking that a 500k audio taper for tone control pot is going to allow more range on that pot, so a smoother tone control. Am I wrong on this too?

Not the exact same subject but the info here would help you understand more:
Video Drop: Tone Cap Shootout (All About Tone Controls Parts 1 &2)

 

[dwizum]

I think smaller value blend control compensated for by a very large value volume and/or tone control is the ideal for both blending and allowing the largest frequency spread (the total resistance to ground of the control circuit via volumes, tones and blends helps shape the top frequencies of the pickups attached).

I agree with this. I often use 500k volume and tone pots, even on instruments where 250k are "traditional" - but I almost always use 250k blends.

I wouldn't give up on the AC taper without trying it, at least if you run out of other options. It's very much a matter of personal preference and depends on how you use the controls. Most people prefer MN, but if you have an MN and know you don't like it, it makes sense to try AC.

 

[Passinwind]

I think smaller value blend control compensated for by a very large value volume and/or tone control is the ideal for both blending and allowing the largest frequency spread (the total resistance to ground of the control circuit via volumes, tones and blends helps shape the top frequencies of the pickups attached).
A large value tone control may not have a “smoother” taper per se, as a large amount of the sweep is just affecting the loading of the circuit (more subtle change) vs the more dramatic change that the capacitor creates near the bottom of the sweep. So if you like to use darker tones, a larger value means you are squeezing those tones into a shorter portion of the sweep and it may be difficult to dial in the subtle shifts (similar to the large value Blend control). As someone who mostly uses the brighter end of a tone control, a larger value gives me more to work with so I appreciate it! Audio taper is the norm for Tone controls and usually seems to work best.

You can also tack in a small value resistor betwen the tone cap and ground to change both effective taper and the max cut feel. Something in the 1-5K range has worked well for me.

 

[Ringhammer]

You can also tack in a small value resistor betwen the tone cap and ground to change both effective taper and the max cut feel. Something in the 1-5K range has worked well for me.

I think this is what Fender calls their “Greasebucket” tone circuit?

 

[Ringhammer]

I wouldn't give up on the AC taper without trying it, at least if you run out of other options. It's very much a matter of personal preference and depends on how you use the controls. Most people prefer MN, but if you have an MN and know you don't like it, it makes sense to try AC.

Finding a solid shaft AC 250k blend seems like some work, so far I’ve had no luck. Same with finding a 250 or 500k solid shaft linear taper pot for volume.

 

[JKos]

I've had good luck with low value (25k works), ungrounded/no-load configuration blend pots. It makes getting an actual mix of the pickups much easier. Much more useful than classic blend pot setups.

 

[Passinwind]

I think this is what Fender calls their “Greasebucket” tone circuit?

I had no idea, but looks like, but not necessarily with the treble compensation cap. In any case I've found it to be exteremely useful.

Did you check the Noll A/C pot on Best Bass Gear BTW?

I've found solid shaft liner taper Bourns pots at Mouser in the past, but IME it often helps to already have the part number and do a search via Google rather than rely on the Mouser search engine.

 

[dwizum]

I order a lot of Bourns pots and have incidentally memorized the codes used in the product numbers years ago, which has been very helpful compared to searching from scratch each time!

PDB181-GTR02-254B0 for smooth shaft 250k linear taper "mini" pot
PDB181-GTR02-504B0 for the same, in 500k

GTR01 in the middle segment would be the same parts but with an 18 tooth "coarse" knurl. You can use setscrew style knobs meant for smooth shafts on those pots too, either just directly - with the set screw clamped on the knurling, which has the side effect of a knob that sometimes sits a little off center - or with a conversion bushing, which gives a pretty perfect fit. The bushings are sold by many guitar parts suppliers, should be easy to find.

I don't think they offer a smooth shaft 250k AC blend as standard, just custom order, when I see them they've shown up as rebranded parts (Like the Noll one referenced by @Passinwind)