Drip Build - EQP1A - Replacement Pots with better feel

[RayBlack]

Hey DIYers,

I am looking for good quality pots to replace the cheap Bourns Pots that were part of the Mouser BOM.

In the Opto Manual there's an ALPS Pot, that is probably higher grade and I will order for my Opto,
but the Pultec Manual does not mention replacement pots.

I am looking for a better feeling pot, that turns a bit more slowly and precise.

There are the ones I want to replace:

HF ATTEN 1K LIN
HF BOOST 10K LIN
LO ATTEN 100K LOG
LOW BOOST 10K LOG
BAND 2,5K LIN

Would be great to get some good recommendations for pots, that are available in Europe.
Perhaps someone has done that before and can share the knowledge.

Thanks!
Ray

 

[Ilya]

Bourns make quite nice pots. Which ones are specified in the BOM? You can look at 51 and 91 series for a replacement. Another option with nice feel is Alpha pots. But they are even cheaper then Bourns.

 

[RayBlack]

https://www.mouser.de/ProductDetail/652-91A1A-B24-D20L

Looks like it was 91 series. This one turns as soon as you touch it, very unstable.

 

[Ilya]

Ok. I checked the pot and it was a 53 series. But torque specs for 53 and 91 series are very close, although they have rather wide margins. Maybe the torque changes from batch to batch. You can also look at 3310 series which has nice feel. But it doesn't have minimum torque specs, so in theory you can get a light one. Although all 3310 pots I bought were rather nice and not easily turned.

P. S. I don't think 7$ pot is cheap. On the other hand, 12$ Honeywell pots are not very pleasant as well. So you never know. I really like Alpha despite being very cheap. It's a pity they are not as compact as 3310.

 

[AusTex64]

I’ve built two Drip EQP-1A’s with the Bourns pots and have not found the “looseness” to affect the performance. Of course YMMV. These are PCB mount pots so that’s going to limit your choices. If it makes you feel any better, I read Eve Anna Manley has has complaints about the feel of the Bourns pots in their gear, but that they have had nearly zero problems with the Bourns pots. That was good news to me.

 

[RayBlack]

Hello there,

AusTex64 so you encounter the same problem with the looseness?
Of course the performance is top notch..but I don't like the fact that
they are too easy to displace...probably will get in touch with Gregory about that.

Thanks
Ray

 

[Rob Flinn]

If you are worried about them turning too easily slice a grommet in half & put it behind the knob to add a bit more friction.

 

[warpie]

You can probably put a rubber o ring behind the pots. I think that's what manley do ?

 

[RayBlack]

Will try the rubber ring method

 

[fragletrollet]

Seems Bourns have different turning resistance on their pots; I`ve used Bourns in my EZ1084`s and my DR2402, and to be honest, I don`t like the feel of them one bit. They might be accurate in resistance and last for a long time, but the turn resistance is way too light (I prefer the smooth and resisting feel of a pot) and there are parts of the rotation where it "sticks" or "scratches" (not audio, but the feel of turning the pot actuator). This means you have to adjust them very carefully.

I`ve used so many other (much cheaper) pots that feel way better (including Alpha etc), but I`ve also encountered Bourns pots (from CAPI) that have much smoother feel.

 

[Ilya]

Seems Bourns have different turning resistance on their pots; I`ve used Bourns in my EZ1084`s and my DR2402, and to be honest, I don`t like the feel of them one bit. They might be accurate in resistance and last for a long time, but the turn resistance is way too light (I prefer the smooth and resisting feel of a pot) and there are parts of the rotation where it "sticks" or "scratches" (not audio, but the feel of turning the pot actuator).

Do you by any chance remember the actual series of these Bourns pots? Or maybe you have a part number for them?

 

[Knotty]

I rectified the issue by cutting a ring of felt and putting it behind the knob. Then set the tension you want, by how hard the knob is pressed against the felt, then tightening the screw on the knob to lock in your tension. I agree the tension is too loose, not only does it make it touchy when setting, but also makes it feel cheap. Felt is the quickest way I found to make things feel expensive haha

 

[iampoor1]

51 series has a tigher feel, but rates life is 50000 cycles.

It's pretty ironic that the chief complaint of 91 series pots is that they don't feel right, when they are such high quality units lol. I guess we are all just used to the feeling of cheap pots...

 

[fragletrollet]

Do you by any chance remember the actual series of these Bourns pots? Or maybe you have a part number for them?

https://no.mouser.com/ProductDetail/652-91A1A-B24-D10L

 

[Malcho]

Hi,
Is 1/4 W enough for potentiometers for Drip EQP1? What do you think?
Time ago I have email from Gregory:
"on the bourns 91 pots i would reccomend cermit type instead of the conductive plastic - if you would like more torque in the turn of the control knobs."

Regards
Plamen

 

[emrr]

Hi,
Is 1/4 W enough for potentiometers for Drip EQP1? What do you think?

Regards
Plamen

1/4w is +24dbm. 

 

[john12ax7]

Keep in mind the Bourns 91 pots have a VERY loose feel to them which a lot of people don't like.

 

[Sc]

Personally I like the feel of the Bourns 81-Series - much tighter. A bit more expensive (2W Cermet)  and have another PCB footprint. But you can bend the extra fixes and the upper pin (mill out the bottom of the pot a little bit) and you meet the 91 print. Works fine with the EQP1 and other Drip front boards ...