Acoustic Zen Crescendo speaker crossover capacitors ... who makes them?


I own the MKl version of the Crescendo and see the crossover uses all Acoustic Zen branded capacitors. Most are blue in color with the smallest values bring black. Does anyone know what company makes these for AZ? I did email the builder, but no answer. Love any information the community may have on this topic. 

128x128grannyring
I understand completely Peter. Thanks for sharing that link. I love the idea of building a nice kit like that. Great idea. I think the designer of my speaker did what was reasonable with the bass board. No doubt about it.

I like thinking and planning on ways to improve what is reasonable and done with perhaps more cost constraints in place for the builder. 
@pbnaudio and others. The two 8 inch woofers are parallel wired. I have drawn out the circuit and taken photos of the board. Please take a look. The 1000uf caps, smaller inductor, and 8 ohm resistor all seem to be included parallel to the amps output to raise the impedance of the bass filter. Two 8 ohm woofers in parallel would deliver a net impedance of 4 ohms. The builder wanted to keep the speaker friendly to tube amps and thus implemented this impedance filter. The speaker is 6 ohms nominal.  I am not sure if this impedance filter reduces the impedance peaks of the vent/port and drivers or raises the nominal woofer impedance the amp sees? Or both? 

Question. Will the quality of the parts in this impedance filter impact bass quality? On paper it seems like no, but I know from experience they can very well have an impact on sound quality. Thanks in advance.

http://s1097.photobucket.com/user/grannyring1/library/Bass%20board%20crossover
Looking at your schematic, you have a impedance correction network across the positive and negative, not knowing the value of he inductor is impossible to tell, you where it corrects, you could disconnect it measure the impedance and see where you get a raise in the impedance.  Changing the caps or bias them in this circuit will not do much to SQ but you could certainly try.

The woofers are connected to a standard 18dB/Oct electrical filter consisting of two coils in series and a 200uF capacitor as a shunt via a 12 Ohm resistor between them, pretty standard stuff. However parts seems to be a extraordinarily high quality. 

Best

Peter
Peter thank you so much. I will leave all alone except upgrading the sandcast resistors. 
The caps are Taiwan or were .I have Never known them to use name brand 
On the few Adagio and crescendo over the last 5 years. They still sound very respectable with a Xover upgrade with boutique caps. 
In thd Bass just put in a bunch of poly bypass caps Solen would ge good enough. 01uf 400v would be fine that would  clean it up a bit. Good Copper gold or rhodium loudspeaker terminals another easy fix.  
If you are open to spend around  $700 while you are replacing the Loudspeaker terminals VH audio has a special. 2 years ago these were $ 1300.
Bybee Golden goddesses on the hot side and then  black ones  on the minus. 
I guarantee you a more detailed quieter backgrounds and just more real soundING. I did these for a friend, I am more surprised at the results and I Allways do upgrade mods. First read a few reviews these were $4k when they first came out. They replaced the 24k hold with a matrix of things. Your call.