Different strings will be hundred times the difference than matched pots. Other factors maybe even more. Lol, you sure picked one of the very least factors to be anal about.
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Pots...am I too anal, orrr.......
- Thread starter mmbongo
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actually, the rig very much matters.
to repeat, if you've got a bunch of compression and overdrive going on (as guitar players do), then an audio volume will indeed bring up the actual percieved volume in an even manner as you turn it up, gradually going from clean to crunchy in the process.
the compression boosts the quiet part of the pot's travel and squashes the loud part, giving you an even sweep from off to full.
if you have a typical clean bass rig (or a jazz guitar type amp), a linear volume will just sound even through its range. an audio taper will stay quiet through most of its turn, then jump up at "10".
the pushback to this point always puzzles me; the difference is obvious and repeatable. it works every time.
linears really shine for V/V setups, because they make finding the "sweet spot" easier.
you never want linear tone pots in passive guitars. they'll do nothing until they're almost all the way off.
Slide on over to the strings section if you really want to see how anal I am about strings
Install each of the four in all possible combinations and see which sound you like best.
Or just don't bother.
Or just don't bother.
I just used the highest rated ones I had since nobody ever really said if there was an advantage to using matched pots.
- Aug 21, 2008
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funny, because i put ernie ball rounds on my bass, they play and sound good, i don't give it another thought
I get consistently good tone with D'Addario XLs. And they last forever. EBs are good too.
We, along with generations of audio designers and scientists say the same thing right back to you. I just looked up what (precious little) quantitative information I could find on actual audio taper volume controls. They do in fact seem to be two segment linear approximations and that makes them no better than linear pots. The two deviate by almost exactly the same amount from the desired log curve at their worst points but in different directions. A linear pot increases too fast at low volumes compared to the ideal, an audio pot too slow and both do the opposite at high volumes of course. In addition the audio pot has a kink in it where the linear curve is smooth. A compressor will tend to exaggerate the error of a linear pot but bring the audio pot closer to the ideal. With a clean amp one is about as bad as the other. Evidently you really, really prefer the errors of the linear pot, most folks prefer the audio pot. It would be nice if we could get the right pots which would have a dead linear effect on output volume with shaft rotation but one can only buy what is on the market.
Keep in mind that this is all predicated on using a volume pot as it was intended, with the output taken from the wiper. A single pickup bass will be wired that way, a B/V/T bass may be, a V/V/T bass (Fender's at least) has the input on the wiper with the output on the top of the pot and I do not know if that makes a difference.
Ken
- Aug 21, 2008
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Which I pointed out earlier.
Now think about where you use the pots the most. I doubt most people use them on the low end of their travel. Not for bass anyway. I know I personally keep my volume on 10 most of the time. Never any lower while playing. When I'm using two volume basses, I keep them between eight and ten, or off. never lower than 8 on both. Same with master volumes. I never use them on less than full. To many, including myself, volume controls are for muting the bass when not playing. I use a compressor anyway, so dynamics are out of the question.
So most use them to back off one pickup a little, and that's where linear taper pots work well.
Now let's look at a blend pot; the good ones use M/N taper, which is two linear tapers:
So clearly thats the way to go for pickup blending, and not A/C taper, which is log/anti-log.
On guitar I've used either to good affect.
and that's where the pushback usually comes from, audio engineer types, as opposed to folks who have actually compared both pots in instruments. (it's common knowledge among us guitar tech types that "audio taper" pots these days are just two-step linear approximations. they still get closer to what's needed in the right circuit than straight linear.)
yes it does, and the difference also makes linear volumes a better choice.
with the pickups on the center lugs, the sweep is not as ideal as when they're on the "input" lugs, but linear volumes still sweep more smoothly;
the big difference, though, is that with the jass bass setup, the tone is "after" the two volumes; this causes the pots to become interactive, in that rolling down the tone makes the volumes drop off even faster from "10", making a bad situation worse.
there's a whole school of stock jazz bass playing where you deal with it by running all three knobs below full-up, so that they're all out of the "jumpy" part of their range, and just deal with the output loss at the amp.
half-right; like i mentioned earlier; that's why audio taper volumes are good for guitar players, who use a way more compressed and distorted signal than typical bass players.
with clean amps, the linear volumes are way closer to the "ideal" sweep than even fairly flat audio volumes.
Which I pointed out earlier.
Yes you did. There are a number of different curves available (all bilinear) in fact and some are very good approximations of the ideal curve. Curiously the ones sold for guitar use, the ones I can find curves for anyway, are no better than linear pots in terms of the maximum error.
That is my experience too. In fact you can use your audio pot in either of its two linear ranges merely by adjusting the amp volume control appropriately so if one of them suits you more than the other just turn the amp volume up or down. The amp pot has the same audio taper as the guitar pot, most likely.
Ken
Audio engineers spend a lot of time studying the effects of design choices in the real world. A surprising number of engineers of all types are musicians actually.
No, in fact a linear pot is the worst and the typical audio pot is the best when used backwards as in a VVT circuit but there is not a great deal of difference among them in this application.
Clearly you like linear pots better. I am quite sure the pots in my Fender are audio and in practice they work just fine in spite of the errors a design analysis reveals. I twist them all the time and I experience none of the flaws you claim they have. My expectation is that linear pots would be neither better nor worse just different in detail. Both kinds miss the ideal curve by the same amount with a linear amp. I'm not sure why the typical audio pot is so far off. I suspect that current thinking on the ideal curve is different from what it was thought to be back when the audio taper was picked and people just keep making pots to the old curve because that is what they have always done. The linear slider pots for high end audio applications are available in bilinear audio tapers that fit the ideal curve quite well.
Ken
so you haven't actually tried them?
you're just arguing theory?
slap a couple linear volumes in a jazz bass, see how much easier the blending is and how much smoother each pickup turns up and down, then get back to me.
We've been over this a hundred times but here goes 101...
Sure audio types all know about Fletcher-Munson and hence KNOW that the ear responds logarithmically to voltage levels controlling sound output. Hence it is OBVIOUS that an audio taper pot which give said logarithmic relationship is the proper volume control to use, right? I mean it correctly equates perceived loudness with angular rotation of the control, right?
Well that IS right PROVIDED the pot is wired into the CORRECT circuit! The taper of the pot is designed to work into an IDEAL circuit situation. This is one (like you might find in an amp or mixer board) where the pot is driven by a more or less ideal voltage source and the output experiences next to no loading.
But this ideal situation is NOT what you find in a typical passive bass! You have pickups with frequency dependent elements (capactances and inductances), you have loading, and you have loading on the the output side of the pot. This is not "magic" these things can be calculated (with some effort) and if you do what you find is that your precious "audio" taper is no longer logarithmic! In fact there is a mod site you can find on-line that actually does the calculation and shows you the loading needed to give an "audio" taper with a "linear" pot!
So while it's not all cut and dried (an active bass where the volume circuit is more "ideal" may work better with an "audio" taper pot) But, people who have TRIED linear pots in your standard Fender passive bass situations pretty much agree that they give MUCH better control over your volume levels than an Audio taper.
Nevertheless, it seems Fender often installs "audio" taper pots in passive basses. Who knows why? So the bottom line is that if you find your volume drops off rapidly on your passive bass, try a linear volume pot. I predict it will work MUCH better!
But nothing is fer sure. As I said it ALL depends on the wiring inside the bass, pickups, amp/cable loading, etc. so there aren't any hard and fast rules except "try it and see which is best on YOUR wiring".
fender originally put 250k audios in all positions of all their guitars and basses up until the jazzmaster, and my guess is that folks are just used to it, so they keep doing it.
It could also be that audios did work better in the compressed, relatively low-wattage tube "bass" amps of the '50s, when the fender bass was first introduced.
- Aug 21, 2008
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Could also be that the taper was really audio on the old pots. Plus, some audio taper rates work better than others. You see these listed as 10% etc. Often on the pot it will say "10" or "20" or some such.
so you haven't actually tried them?
you're just arguing theory?
I don't have any experience with linear pots in a bass but I have considerable experience with the audio pots in my bass and they work fine, no complaints, not even a hint of the issues you say they have. So what is a linear pot going to give me? A curve that differs in detail but is no better or worse overall. The performance of a linear pot in a passive guitar setup is anything but linear and to the person who wanted to educate me on the complexities of the situation, thanks but I already know all that and it has all been accounted for. I do that sort of thing for a living and long, long experience teaches me that physics never lies. Those who think it does did not do the analysis carefully enough.
So what is the real difference between them? It is not guitar vs bass, it is not compressor vs clean, it is simply that you like one thing and I like another. Simple as that. You really like the response that linear pots give you. There is nothing wrong with that and you are not alone. Nor am I, plenty of people prefer audio pots, even the crappy curve that evidently has taken over from more correct curves, more on that later.
So discussions like this can go on and on forever trying to "prove" that one is right and the other is wrong or we can just acknowledge the true situation: it comes down to a personal choice and rather than trying to insist that any choice but our own is stupid we can just live with the fact that one person might prefer linear, one audio, and others still won't prefer one over the other. If you are happy with what you have there is no reason to change, if you are not then the other taper may suit you better.
I tried doing a web search on "cts audio pot curve" and came up with some interesting results. The most common audio taper on the market today and presumably in basses bought new off the shelf is a "10%" taper": at 50% shaft rotation the resistance reaches 10% of its ultimate value. As I said previously this just seems wrong, it misses the ideal "log curve" (which is really a power curve, not a log curve) by a considerable amount based on current thinking on the human loudness response. However there are a few guitar parts companies that have custom ordered "30%" audio taper pots for sale because that is what guitar makers used in the past! A 30% audio taper fits the ideal loudness curve very, very well.
I have yet to find any comments on why audio pots today have the 10% curve but if you like neither linear pots nor the common 10% audio pot you might find that the 30% pot is exactly what you are looking for.
Ken
Sorry, but that was the only relevant line out of that post.
This isn't gonna make or break the show or lose you the big gig, but given the choice, linear volumes work better in basses for most applications. That's all there is to it.
(edit: i mean that's all there is to the difference, not that my argument is final or anything
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