CTS Pot Problems

[HotBluePlates]

Apologies if this has been posted elsewhere.

A recent thread on another forum pointed out dead spots in the rotation of recent CTS pots, and a large jump from no-volume to volume.  Follow the link to see the carbon tracks in current pots vs 70s CTS pots.

Looks like these have declined in quality, just like other components that used to be forum-darlings.

[Ed_Chambley]

CTS is making different quality pots.  Thats for sure.  The 450 and 450G are the go to pots for most Amps and Guitars.  Audio Taper of 10, 20, 30 and the ability to order in 10% tolerance as opposed to 20 makes a different pot.  I just completed a PAF neck/ 52 Bridge Telecaster.  Used Dual Concentric Pots from CTS on 250/500.  Dual knobs so with the switch in the center makes it have individual Vol and Tone for each PUP.


It is very important to get a 500K Plus on the neck Pickup, volume and tone of the humbucker since the neck pickup is about 1.5 inches further towards the nut.


It took a while, but I finally found a combination of resistors to get them high enough and a treble bleed that lets a little treble leave.  I have found they seem to all measure low.  Hate to see it, but it is the way of the future.


Hello HBP!

[mresistor]

I have been using Alphas   no problems.  CTS is way more expensive anyway.

[2deaf]

This has been going on for some time now.  I never noticed it because I rarely set anything in the "1" or "9" range (Marshall scale).  Then I put a 1MA CTS in a high-gain 100W amp for the master volume and I noticed it then.  That amp runs between "0" and "1" in residential neighborhoods, but this thing went from nothing to window-shaking along about "2".  I replaced it with an Alpha and everybody in the whole neighborhood sat back down on their couches.

I have over 30 brand new CTS pots sitting here and they all do nothing at first at both extremes.  Even after I noticed it, it didn't bother me in most positions.     

         

[HotBluePlates]

Back over on that other forum, they might have figured it out.

CTS 450G data sheet

Nothing happens until ~15% rotation.  But when people want a switch on their pot, that first 10-15% is taken up by the switch-click.  Seems CTS is only bothering to print one kind of wafer for switched/non-switched pots.

... I put a 1MA CTS in a high-gain 100W amp for the master volume and I noticed it then.  That amp runs between "0" and "1" in residential neighborhoods, but this thing went from nothing to window-shaking along about "2".  I replaced it with an Alpha and everybody in the whole neighborhood sat back down on their couches. ...

There are a lot of "audio" tapers available, from 5-30%.  The H (25%) and J (30%) tapers are as loud on 2 as the C (5%) taper halfway up.

Vendors don't always tell you which of the 6 audio tapers you're actually getting.

[kagliostro]

Ciao HotBluePlates

Thanks

That is very interesting

Franco

[2deaf]

The 450G series has a bunch of tapers, but the 450 series only has linear and 10% audio.  AES sells both the 450 and the 450G series and even specifies a J taper on some.  I always order the 450 series. 

The thing that was most annoying with the CTS as a master volume was the all or nothing behavior.  If it just did nothing at first and then started with whatever taper, then I could have lived with it. 

 

[Ed_Chambley]

I have has much better luck with CTS new until recently. I do have a lot of Allen Bradleys. I found a dealer that only uses 450 within 10. Measures and marks all top values.


I just rewired my Les Paul. Every 460G short measured 524k, all of them. This finally made it so I could use a .27 cap bridge for a lot more crunch. I use .18 in the neck. Low output PAF types made by Peter floremce. RiP.


I have had a number of Les Pauls, this one is perfect.

[Ed_Chambley]

Oh, i cannot stand the fake 10 percent alpha taper. Why do I want my amp wide open with over half the rotation.


I prefer A 30 taper on gtars. 25 on amps. Log.