Dumb pot question

[drbassman]

I knew that would get your attention!     Actually, I always use CTS pots in my builds.  With my new semi-hollow design, I'm sliding the pots under a hole cut beneath the pup cavity ala the new Guilds rather than through an f-hole. 

I was thinking about tolerances and such and realized the mimi-CTS pots would make my life a lot easier during installation.  Anything inherently wrong or kinky with the minis from CTS?  I'm assuming the same high quality as their standard pots or is there something I should know about them?

Just wondering.........

[Granny Gremlin]

Most carbon track pots are 20% tollerance.  Which isnt great, but does the job.  The minis (16mm) are no worse than the full size (24mm), at least any more (back in the day people did look down  on them but I'm not sure why - all the imports used them maybe, and I know some of those pots were horrible... now we have even smaller PCB mount ones; miniaturization is mature). 

Alpha is another good brand for pots (and much cheaper); they make 16mm ones that I use in my pedal builds (cheapest place on the net by 50% easy: BLMS - he's reputable).  My top pick would be Bourns pro audio series (even over CTS) but I'm not sure they make a mini.

[amptech]

I knew that would get your attention!     Actually, I always use CTS pots in my builds.  With my new semi-hollow design, I'm sliding the pots under a hole cut beneath the pup cavity ala the new Guilds rather than through an f-hole. 

I was thinking about tolerances and such and realized the mimi-CTS pots would make my life a lot easier during installation.  Anything inherently wrong or kinky with the minis from CTS?  I'm assuming the same high quality as their standard pots or is there something I should know about them?

Just wondering.........

I use only CTS pots. I know many (at least outside US) think they cost too much and that alpha might do the job just as well. Ten years ago  I built three tube amps that was identical except pots. One CTS, one alpha and one even cheaper chinese pot. Different guitarists had them, so it was no scientific experiment. But the cheapo´s was crapping out in about two years. The alphas were ok except one scratchy and one loose after five years. The CTS pots are all good even today, and they have the bonus of feeling just as tight as new.

As for the mini CTS´s, I´m installing a double one as a blend pot (to blend a P and a mud ) in a fender P, looking forward to try that one out!

I have an acoustic epi that i transformed into a jazzbox with f holes. I used the small CTS´s in it, and as I work the pots I cant really tell any difference between them and the big ones. I expected them to be more ´jumpy´perhaps, but they are fine! 

Add a handmade oilcap to the tone pot and they sound fabulous!!

[Granny Gremlin]

Alphas have come a long way in the last few years though; they don't feel (when you tuen them; tactile sensation) like the other cheap pots (e.g. BDI) anymore.  And developing scratchyness/looseness greatly depends on use and abuse, but I can understand not wanting to risk it.  I maintain Bourns are the top of the heap and still cheaper than CTS (especially outside NA); it's just a relatively new product line for them  vs CTS.

[Dave W]

You can buy CTS pots in tighter tolerances than +/- 20%. I've seen them in as low as +/- 5%. But I don't recall seeing mini pots with closer tolerances.

[amptech]

Alphas have come a long way in the last few years though; they don't feel (when you tuen them; tactile sensation) like the other cheap pots (e.g. BDI) anymore.  And developing scratchyness/looseness greatly depends on use and abuse, but I can understand not wanting to risk it.  I maintain Bourns are the top of the heap and still cheaper than CTS (especially outside NA); it's just a relatively new product line for them  vs CTS.

I recently put Bourns pots in another test amp. The price is fine, but i expected them to be made in uk or us. The metal shell ones I ordered had were all made in china, with the exact same toolmarks as another unbranded chinese sample that cost half of the bourns.
Time will tell if they hold up!

[drbassman]

Another question or two:  what's the difference between audio taper and liner pots and their application?

[Psycho Bass Guy]

"Audio" taper pots have a logarithmic taper which matches our aural perception of volume. Linear pots vary with a linear taper. If you plot the resistance of each, the audio pot is a curving arc and the linear pot is a straight line at 45 degrees.



Applications vary, at least in passive electronics, by taste.  There is more to tone than pickup output resistance. Current matters too, and there are big humbuckers which use linear pots and sound fine. A linear pot with a "normal" pickup will have a VERY small useful taper and be practically an on/off switch for most of its throw.

[Dave W]

FWIW, most humbucker-equipped Gibsons have used 300K linear volume pots since about 1973 (tone pots are still 500K audio taper). Some aftermarket electronics sites say otherwise, but they're mistaken.

[Granny Gremlin]

Quite sure that's not the case on my 1980 Sonnex Custom, but I have seen some like that.

[amptech]

FWIW, most humbucker-equipped Gibsons have used 300K linear volume pots since about 1973 (tone pots are still 500K audio taper). Some aftermarket electronics sites say otherwise, but they're mistaken.

As early as that? My '78 les paul guitar had all 500K log in a standard 2 humbucker wiring.

[Dave W]

As early as that? My '78 les paul guitar had all 500K log in a standard 2 humbucker wiring.

http://archive.gibson.com/Files/schematics/lespaul2.gif

See the note that says 300K after 7-1-73.

That doesn't specify whether it applies to volume, tone or both, and it doesn't specify linear or audio taper, but a look at later schematics confirms that the 300K was used for the volume pots, and the 300K Gibson has always sold as a replacement is linear taper.

[drbassman]

I'm finding the 3ook pots harder to find these days.  Might just go ahead and use 250s if necessary.  Not that big a difference in my application.

[Dave W]

I'm finding the 3ook pots harder to find these days.  Might just go ahead and use 250s if necessary.  Not that big a difference in my application.

Musicians Friend/GC and Sweetwater carry the Gibson branded 300K linear pots, or you can buy them direct from the Gibson store.

[amptech]

I'm finding the 3ook pots harder to find these days.  Might just go ahead and use 250s if necessary.  Not that big a difference in my application.

I've noticed CE distribution does not have them anymore, although they do sell both cts and gibson branded cts pots.