Found it – here is the brochure from 2011 which includes the M3-PX.
Also I have a new website that has just gone ‘live’ with some of the components now moving – still work to be done… but if you go ‘loudspeakers’ menu and scroll, you will find my way of describing the various models which shows the cell number used (horizontally) and biggest thing to see or consider for performance is the radiating area which is from left to right descending.
Hello Jim
the M-3PX is more or less a M645 – I had one around 2012 and sold to a customer in 2106 I think. I will check my office tomorrow for the detail.
I have been representing Sound Lab in Japan since 2012 and am recently giving support to anyone anywhere – please let me know if you have any specific questions I might try to answer.
I have a website with some information which may be interesting … but it is still in progress and will update more soon with information.
Note the reference at the bottom and that the “M” stood for “Millennium”. In terms of height and width, it fits between the current M545 and M645 models.
If any forum members have the M-3PX model specifically, I have a few questions that would be very helpful. I could not find a single thing about this specific model anywhere on the web or Soundlab web site. If not, I’ll see if Soundlab can provide info, but had a few questions that an actual owner might be better able to answer.