LDR matching (Xenotron example)

[Matopotato]

From reading up on a few posts, LDR matching can be very important. (E.g. Phase II as @Chuck D. Bones wrote in #5 here).
Is it mostly important to match the light or the dark resistance? Or is that very situation dependent?

I am looking at Xenotron build (https://aionfx.com/app/files/docs/xenotron_documentation.pdf), 4 LDR/LED pairs. One is on a BBD breakout board and here it is about getting the LED right.
On the main PCB there are three pairs, but looking at the schematics one pair is a bit more on its own.
So that leaves two pairs, LDR1 and LDR2:

In this situation, should they be matched?
If so, both dark and light resistances? Or one is more important than the other.

In the kit I bought I have 3 that sort of match light 1 and 2 and dark 1 and 3...

 

[Synchrony Pedalworks]

I did not match my LDRs for this build and it sounded wonderful.

 

[Matopotato]

Thanks,
Anyone with any thoughts on matching in general:
Is light resistance or dark resistance more important to match?
Or varies greatly with build/context?

 

[Scruffie]

Thanks,
Anyone with any thoughts on matching in general:
Is light resistance or dark resistance more important to match?
Or varies greatly with build/context?

I'd say it probably depends on how willing you are to settle for good instead of perfect, you can build most any optical DIY build without matching unless it's specified or you're trying to replace a dual vactrol with two singles in specific circuits... the Mutron III would be an example of a circuit I would match for but that's in a tuned filter.

Personally, if I was going to I'd just match for the highest light on resistance and leave it at that... you could go mad trying to sort through hundreds of LDR's especially when you've got to account for settling time and you would need a very large batch to start making accurate matches.

If there was something I really wanted the best sweep out of I might match at 1mA and 10mA for example but even then a 10% tolerance is perfectly acceptable.

Plus, pretty sure I read Mike Biegel talking about how the unevenness was part of the Mu-Tron Phasor sound so that's a good excuse to accept close enough.

Also important to remember, LDR's drift with age so your tightly matched circuit isn't going to be tightly matched for ever and most of those vintage pedals we love are probably pretty out by now if they were even matched in the first place.