DIY biamp 6-24 crossover

Thanks Macka for the response.
Better quality 25k linear trimpots might be useful, but I think I've got the response to the stage of using fixed Rs.
I've matched inputs/outputs for HP & LP stages on both boards using sine waves at various frequencies & a 2-channel oscilloscope.
Then confirmed into & out of both channels of all 3 amps.
Final confirmation was measurement sweeps with REW at 1cm from woofers, 50cm from each mid & tweet on axis. Final measurement at listening pos with sweeps & pink noise.
Confirmed with iPhone App that shows spectrum of actual music (new phone's mic is calibrated to the app).
Drivers are very closely matched for my NS1000s, variations are all due to room nodes/reflections.
Unbalanced is working fine with no hum or noise.
I make my own interconnects & know how to shield & terminate correctly (Rane Technical Note 100, i think, is my reference).
Phase measurement & matching is an aspect I'm still learning; I've been using REW for 5+ years & there are still "Ahah!" moments when something clicks.
The 6-24XO has replaced a fancy DSP-based XO (which is LR4 slopes, which don't sound as good as LR2), & sound quality (musicality) is superior, less "tiring".
So, apart from 50k trimpots, pretty happy.
May not need other 4 kitsets I bought to do full balanced build, so if anyone in Australia needs them, PM me (price will be my landed cost+postage).
 
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I have been running my two way monitors (b&w cm5) with the analog crossover (2 pole) since the weekend and I must say I am very pleased with the result! First thing i noticed is that fading sounds like recording room echos and instruments seem far longer audible!

Measured frequency response is similar to the passive crossover (first order). However, 10k to 20k is rolled off compared to the passive crossover. Any clues on what might cause that?

Up next is trying 4 pole at a lower xover point.

Al this fiddling is in preparation of my first 2 way speaker project with Jbl2450 on yuichi horn (on order) and faital 15pr400[emoji16]

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