Yamaha NS-500m crossover schematic help

JMS

Member
I posted this previously in the speaker forum and it was buried by traffic, before anyone that might be able to help could see it. I have exhausted every resource I could find to obtain a copy of the crossover schematic for my new to me NS-500m speakers. It seams the service manual that has what I need is a closely guarded secret. My plan is to recap my pair after I finish a current project and I would like to source new caps before I tear these down. These speakers as they are now are pure pleasure to listed to and I don't want to have them out of commission any longer than necessary. All help is greatly appreciated.

JMS
 
Thanks for the links SW. From the pinkfish link it seems the cap values are almost identical from NS-200m to ns-500m to ns-200ma. I have actual crossovers from 200m's and 200ma's and the only difference between the 2 is 2.7uf cap for the 200ma vs 2.5uf in the 200m and 500m. Yamaha did change to non polarized electrolitics in the Ma's. As far as inductors go 200m and 500m are ferrite bobbins and square laminated iron bars in the 200ma's. I don't know if their values are the same but I would not be surprised if they were. As of now I am enjoying the new to me 500m's and I am in the process of a complete rehab of a pair 200ma's before the 500's go under the knife.
JMS
 
I would open them up to see what's installed myself.
Lots of times you'll have changes from what the schematic says and that's a pain in the behind when you've made your order and a few caps are wrong when you get in there.
 
This is what I got from viewing pictures of the actual crossover. I'm currently using the crossover for a center channel speaker I made using ns 500 speakers. Updating the inductors and capacitors(of which were out of spec) increased the clarity of the instruments and voices.
 

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All help is greatly appreciated.
I've posted elsewhere about the questionable benifits of using boutique components in the "bypass" positions.
Using a NS-690II as a reference (it was handy)
NS690_Crossover.JPG

I think C-3 and C-1 are used to divert unwanted frequencies away from the speaker, that said, they are not in the audio path
and unlikely to affect sound quality. The manufacturer probably used electrolytics there. I would go for a budget polyproplyene
max $10- and put the saved funds into better caps at C-2, C-4. Same applies to L2, L3, foild inductors in those positions
would be a waste.

Happy to be corrected on this...
 
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