• TalkBass has been independent since 1998. Add your voice.
    Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
    Join free Log in
    Want zero display ads or expanded classifieds tools? Compare plans.

Best potentiometers for bass

pickles

pickles

Gold Supporting Member
Mar 23, 2000
10,454
2,836
Ventura, CA
#1
I'm looking to buy some pots for rewiring my bass, and I've got some specific requirements.

- 250k
- audio taper
- mini pot
- high quality
- stiff turning feel (so brushing my pinky against the knob doesn't move it)
- fit standard j-bass knobs

I'm having trouble finding any description of how "loose" the pots are. The pots from stew mac I got are awful. They are really loose turning and now one of them has intermittent signal. I want those really nice mini-pots that I find on all my favorite high end basses -- where do I get them?
 
#2
I recommend linear taper for volume pots and audio taper for tone pots.
Link Removed

http://stores.shop.ebay.com/Tricked-Out-Guitar__W0QQ_armrsZ1

You didn't mention what bass in particular you were upgrading.
Keep in mind a P pup is a humbucker design and really works well with a 500K ohm pot. Usually, though not set in stone, humbuckers 500K ohms, single coils 250K ohms. I recently changed to a 500K (linear taper) for my single coil Bart J and I'm hearing more output.
 
#4
Check out small bear electronics. Their pots are great quality, and small. The only problem is their shaft diameter is slightly larger than the standard knob. I think certain set screw knobs still fit on them, though. Also, $1.25 each sure beats the minimum $5 most guitar retailers charge.
 
#8
Clark Dark said:
I recommend linear taper for volume pots and audio taper for tone pots.
Click to expand...

line6man said:
Personally, I would strongly recommend linear for volume and audio for tone.
Click to expand...
my flag is firmly planted in this camp as well.

audio volumes will drop off suddenly from "10", making subtle shading of the two pickups tougher than it needs to be.

linear tones are worthless, doing nothing until they're almost all the way down.

if you want a loud, grindy, aggressive tone, put in 500ks all around.
 
#10
Jerry J said:
Mr. Sadowsky says audio taper for volume. At least on his basses.
Click to expand...

Well, I guess that settles it!

Actually guys the correct answer is "It depends".

In other words it depends upon how the pots are wired. In the case of a volume control, you may be surprised to learn that a linear pot actually can give a logarithmic output vs rotation.

This occurs when the input is into the end of the pot with the other end grounded and the output from the slider. The catch is that if you load the slider with an R to ground (Which is usually your amp's input impedance) the attenuation of a linear pot will approximate a log curve (like an audio taper pot). The best approximation occurs when the ratio of the pot value (say 250k) to the slider load is 6.7 to 1. So that if your amp input is a common 50k you get a pretty decent log curve even if the ratio isn't perfect. For such a circuit to actually produce a linear relationship the amp would have to be non-loading (say 1 meg input impedance) and then you'd have to use an audio taper pot to get a decent distribution of volume with rotation.

Other circuits such as ones that put the pickup to the slider may work one way or the other it just depends...
 
#11
So true Bassbenj! It does depend on the circuit design. ;)

Pickles originally said that he was looking for an audio taper.

As far as a source for CTS, Guitar Parts Resource has a good selection. Both audio and linear tapers, split or solid shaft but not too sure about the being a "mini" configuration.

Link Removed

And AllParts has the CTS mini....
http://www.allparts.com/ProductDetails.asp?ProductCode=EP-5485-000
 
#12
bassbenj said:
In the case of a volume control, you may be surprised to learn that a linear pot actually can give a logarithmic output vs rotation.

This occurs when the input is into the end of the pot with the other end grounded and the output from the slider. The catch is that if you load the slider with an R to ground (Which is usually your amp's input impedance) the attenuation of a linear pot will approximate a log curve (like an audio taper pot). The best approximation occurs when the ratio of the pot value (say 250k) to the slider load is 6.7 to 1. So that if your amp input is a common 50k you get a pretty decent log curve even if the ratio isn't perfect. For such a circuit to actually produce a linear relationship the amp would have to be non-loading (say 1 meg input impedance) and then you'd have to use an audio taper pot to get a decent distribution of volume with rotation.
Click to expand...

??

i hope your bass amp doesn't have a 50k input impedance, or all your passive basses will sound like ass!

the math is interesting and all, but in reality, linear volumes on basses work more evenly than audios whether the pickup is tied to the center lug (jazz bass) or the input lug (p bass), and whether the input impedance is250k or 2Meg. (by "reality" i mean that i've been installing linear volumes on basses for years now and in every case the result is an obviously more even sweep from "10" to "0".)

i can only guess that sadowsky specs audio tapers because that what fender always used; anyone i've talked to who's actually tried linear volumes on basses prefers them.

although, i have noticed that onboard preamps after passive volumes tend to reduce the big drop from "10" to "8" that audios create. linears still work more smoothly here, though.
 
#14
walterw said:
??

i hope your bass amp doesn't have a 50k input impedance, or all your passive basses will sound like ass!

the math is interesting and all, but in reality, linear volumes on basses work more evenly than audios whether the pickup is tied to the center lug (jazz bass) or the input lug (p bass), and whether the input impedance is250k or 2Meg. (by "reality" i mean that i've been installing linear volumes on basses for years now and in every case the result is an obviously more even sweep from "10" to "0".)

i can only guess that sadowsky specs audio tapers because that what fender always used; anyone i've talked to who's actually tried linear volumes on basses prefers them.

although, i have noticed that onboard preamps after passive volumes tend to reduce the big drop from "10" to "8" that audios create. linears still work more smoothly here, though.
Click to expand...

Actually amp input impedances vary all over the map. Some actually ARE 50k! (read some amp specs) As for 50k making your passive bass "sound like ass", then what does the vol/vol wiring where the pups go to the sliders do? Then the impedance drops from the amp input down to ZERO. Just LISTEN to how my OLP changes tone with volume settings!

[we are talking about how the impedance seen by a pup changes the response of the circuit consisting of the Pup inductance, capacitance, and load resistance]

But I must admit that I too in most cases find a linear pot more even than audio ones. Which I presume means that the rest of the circuit is interacting with the pot in a way that makes linear work better. But on the other hand I found that the input impedance on my active Fender to the pre was 1 meg. A linear pot did not do it in that case. The audio taper that Fender had installed fixed the problem.
 
#15
walterw said:
(by "reality" i mean that i've been installing linear volumes on basses for years now and in every case the result is an obviously more even sweep from "10" to "0".)
Click to expand...

I agree with you 100%. I actually have audio tapers in my passive VVT bass and I hate it! I had some laying around, so I used them. I have to switch them to linear ASAP.

They are usable from around 8-10. Under that the output drops off so fast that I cant blend the two pickups unless you turn both volumes down.

I like linear pots for tone too.
 
#16
Probably the best pots for anything would be made from Ceremet or conductive plastic.
They are normally military grade sealed.

Companies like
Bourne
Vishay-Sfernice
Claristat
Alan Bradley come to mind.

Most stock pots are Crap carbon elements.

I don't have much to say about tapers it depends on what your doing.

Does anyone know who's pots Alembic is using they are really nice.

I'm sure you could find something on Digi-Key or Mouser.

I'm not sure where you would find the friction specs maybe they mention it on the manufacturers website data sheets.
 
#18
spode master said:
Probably the best pots for anything would be made from Ceremet.
They are normally military grade sealed.

Companies like
Bourns
Vishay-Sfernice
Clarostat
Alan Bradley come to mind.
Click to expand...

All very high quality pots.

Does anyone know who's pots Alembic is using they are really nice.
Click to expand...

I have a couple of Activators preamps here, and they are using Clarostat pots.

Noble is good also.

.
 
#19
bassbenj said:
...I found that the input impedance on my active Fender to the pre was 1 meg. A linear pot did not do it in that case. The audio taper that Fender had installed fixed the problem.
Click to expand...
now that's interesting. you're talking about the typical 3-band fender preamp with the volume pot mounted right on the card? what did swapping that with a linear pot do?
SGD Lutherie said:
I like linear pots for tone too.
Click to expand...
that's also interesting. every time i've encountered passive linear tone pots, the behavior was they did nothing until almost all the way off, at which point the tone darkened like it was on a switch rather than a pot.
 
#20
I am reading this with great interest! This is all kinda new stuff for me. And I see the general consensus is Linear for tone and audio for volume.

So in general companies like Fender and Squier and Sx and on and on, in their passive Jazz basses,would have one linear pot and two audio pots, correct?

And on a typical passive jazz bass this is the norm, yes? And 250k is preferred over 500k too? Also the Squier CV and VM are using 250k pots as well?

Lots o Questions tonight...:cool:

walterw said:
that's also interesting. every time i've encountered passive linear tone pots, the behavior was they did nothing until almost all the way off, at which point the tone darkened like it was on a switch rather than a pot.
Click to expand...

I know what you are saying, all my basses do that. But I have found while at about 1/4 to 1/5 of the way to the basement there is a sharp break in the tone such as you describe, the tone will continue to brighten all the way up to the top of the pots range. It is just very subtle. Would an audio tone be even across it's range then? In a passive jazz bass?
 

Latest posts

Top Bottom
Back