Best way to balance control to the crack

[phatfish]

Greetings!  I recently finished adding the speedball to my crack and I'm loving the sound and the building experience.   I'd be buying a Crackatwoa if the kit was available. 

I currently have balance control on my solid-state phono preamp which I use.  I'm planning on building up an Eros2 which I would like to run directly to the crack and fear I would miss the balance control. 

Why:
My ears themselves seem to be a bit unbalanced and I prefer to have some degree of balance control even when using a stepped attenuator on my solid-state streaming system.  This isn't simply to overcome low volume issues with the stock pot. 

The plan: 
Add a 100k Balance Pot in series between the RCA inputs and the existing 100k volume pot.  Mount it roughly to the left of the vents. 

Questions:
Is this a good/sane plan?  If not, what is the optimal way to add some form of balance control (within or outside the crack).

I read in the FAQ that the resistance of the pot isn't really important (25k-250k).  I'd love to know more about why that's the case.  Would adding the balance pot as described make this similar to a single 200k pot?

Any gotchas I should look out for?

Many thanks for any answers and assistance!

 

[Paul Birkeland]

Man, this is such a simple sounding question with a lot of viable answers.  There's some good reading here:
https://sound-au.com/pots.htm
Our kits with balance controls use figure 9 on that page, and I would recommend starting with that.

 

[phatfish]

Thank you Paul.  That link perfectly explains how to wire a normal volume pot for balance control, something I didn’t even know was an option.  I was planning on getting a 100k audio note balance pot specifically for this purpose…still might buy great to know there is a much more reasonable option!

I still feel lost about the impact of putting more pots and/or resistance in the signal path tbh.  I’m confident it’s a non issue based on other bottlehead products doing this, but I’d like to know what something extreme like adding 10 pots (nothing I would actually do of course) would do?  High frequency roll off?

Edit: I suppose at the center position the balance pot wouldn't be adding any resistance, and not much to one channel when slightly off center.  I'm still confused why a pot resistance of 25k-250k wouldn't make much difference.  Wouldn't the 25k pot offer less resistance at the same position compared to a 250k pot?  Wouldn't that affect the audio signal in some appreciable way? 

 

[Paul Birkeland]

Lower resistance potentiometers decrease the input impedance of the amp and can load down your sources.  Higher resistance potentiometers are more susceptible to picking up noise.

 

[2wo]

Have you considered using separate pots/attinulators for each channel? Like the early Foreplay.

 

[phatfish]

Appreciate the explanation Paul! 

2wo: I did briefly consider, but I tend to adjust the volume frequently and the balance infrequently, so I’m quite set on the balance control. 

I’m ordering parts and will update here on the results.  8)  I appreciate the help.

 

[phatfish]

Success!  Thanks y'all.  8)

The audio note balance pot ain't cheap, but I gotta say I really like the center position feature it has compared to using a regular pot for this purpose.  Parts Connexion was also quick to provide a wiring diagram specific to this pot.