PMC BB5 passive crossover schematic info wanted

[darkmatter]

I am looking for any details or information concerning the crossover schematic for the PMC BB5 passive monitor speaker system.

Obviously this will have to be from someone who has reverse engineered or traced the crossover circuit, as such information is copyrighted.

A layout of the components would be a great help.

Pics of the speaker here

PM or post if you can help

Thanks

 

[JonSnell Electronic]

I think you will find that information has copyright.

 

[Charles Darwin]

Besides copyright you would need the PMC mid dome which is not actually for sale.

 

[planet10]

Yes, XO map drawn by PMC will be copyright, but maybe someone has reverse engineered the XO. It is at least worth some theoretical value and would be interesting to see.

dave

 

[darkmatter]

Yes, XO map drawn by PMC will be copyright, but maybe someone has reverse engineered the XO. It is at least worth some theoretical value and would be interesting to see.

dave

Thanks planet10, I will only be seeking information that has been reverse engineered or traced, I do not want to fall foul of any copyright infringement.

The information is for guidance only, as I want to find out the bandpass topology used for the midrange, I think it has 4th order electrical slopes.

Thanks,

DM

 

[system7]

Ah, we are unlocked again.

We did a huge and largely pointless thread on the similar Wilmslow Audio Prestige.

FLOOR-STANDING Loudspeakers

It's actually a difficult speaker. But uses 12" Volt bass and 3" Volt dome mid. 750Hz and 3kHz XO, I'd guess.

I have a typical circuit from that thread below. It actually modelled horribly. The dome mid doesn't play nicely with the bass slopes on simple filter. I'd never be tempted by a speaker of this type given a regular cone mid or two works so well.

 

[darkmatter]

Ah, we are unlocked again.

We did a huge and largely pointless thread on the similar Wilmslow Audio Prestige.

FLOOR-STANDING Loudspeakers

It's actually a difficult speaker. But uses 12" Volt bass and 3" Volt dome mid. 750Hz and 3kHz XO, I'd guess.

I have a typical circuit from that thread below. It actually modelled horribly. The dome mid doesn't play nicely with the bass slopes on simple filter. I'd never be tempted by a speaker of this type given a regular cone mid or two works so well.

Indeed the curcuit design using the VM752 mid was way out in my view, the WM752 unit needs 3rd or 4th order electrical slopes as a minimum. The ATC mid used in the schematic you posted is a completely different unit in all respects. I will revisit the thread for reference only.

 

[cyte]

The schematic and PCB are proprietary and copyrighted.

PMC state in their marketing that their 3-way passive crossovers are 4th order Linkwitz-Riley.
That's really all you need to know.