DIY biamp 6-24 crossover

My crossover is misbehaving...

After a few months of flawless operation, it has started producing moderate level white noise on one output. This isn't affected by the pot, or preamp level - same noise regardless. I have checked all connections, solder joints, searched for bits of debris that might be causing this - nothing that I can see. I'm now wondering if a component (transistor?) might have failed?

Is there a way of testing components on the board to identify possible culprits?

As always, any help gratefully received.
 

Trying to get all the parts needed to build a few of the XO's​

1000uf caps are no longer in stock at digikey.​

Can you suggest a replacement ?

Also, is there an improvement from using the vishay 10 position pots ( which i cannot find, but i did find 23 position pots ) or any other advantage ?
And the same question for caps, any difference, even a small one ,in using something like claritycaps instead of Wima ?
 
Hello RolandPSP,

I have built my 6-24-crossovers with bourns 25-turn-pots. I think they gave me easier adjustment of the crosssover points / - frequencies. No reason to use them soundwise.
For sure you can experiment with different caps. I made one version with WIMA-caps in the filters
and Nichicon UES bipolars as decoupling caps (before and after the buffer cells - or input and output).
As described in Nelson Pass article and bom. Sounds very nice.
Then I used Mundorf-caps and a few other brands. The differences were in my opinion that marginal...
I do not want to say that you shouldn't try it. Buy good caps. But caps which cost more than the 6-24-kit
and all devices together - makes no sense to me.
I wrote it many times - I hope the rest of your system is as good as this active crossover with the WIMAs
and some nice decoupling caps.
I changed the volume -pots at the input to 10-turn-pots for very accurate volume-adjustments between
high- and low-pass section.
But this is my opinion. 😉
Cheers
Dirk
 

Trying to get all the parts needed to build a few of the XO's​

1000uf caps are no longer in stock at digikey.​

Can you suggest a replacement ?

Also, is there an improvement from using the vishay 10 position pots ( which i cannot find, but i did find 23 position pots ) or any other advantage ?
And the same question for caps, any difference, even a small one ,in using something like claritycaps instead of Wima ?

I would recommend a higher voltage rating, 35ZLH1000MEFCG412.5X20​

 
This is one possibilty to use bigger caps in the filterstage...
Cheers
Dirk
 

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