Armortek

Who is the manufacture of the sound boards that Armortek uses in the latest RED box modules? Can they be modified? or sounds changed.

Once the Red box is opened the warrantee is obviously void. You'll probably find an amplifier and a sound module plugged into add on distribution board.
The sound model would most probably be a Benedini V2 which could be reprogrammed.
You'll need the Benidini programming lead, a PC, the Benidini programing file (free file), instructions and the original sound module program file to keep the primary start, running and shut down sounds.
Auxiliary sounds (Guns, voice etc) can be added to, or removed.
You'll still need the original sound program file to make any changes to these sounds if you want to keep the primary sounds. (This original file may be owned by Armortek)
I believe, but don't quote me, you can change or alter certain parameters outputs etc (Not sounds) without the the original sound file. These you'd have to lookup if that was your desire.
If it were me, and you found a Benidini V2 inside the red box which now has avoid warrantee. I would purchase a brand new V2 programable module from Benidini and program it with your own sounds or with Benidini's own sounds from his free library. Keeping the original sound module intact.
That way you can mess with it as much as you like without the fear of making a mistake.

The card is very versatile and more importantly for simple mind like mine, easy to use.

Thank you John , that's pretty much what I was looking for . As someone who is very familial with the world of out door large scale trains and their sound systems I have some issues with the Benidini rather frustrating and rather featureless. I will take your advise though and see what I can do with it

There is an alternative that works well and has a wealth of different settings: a Beier USM-RC-3. I use this module in my easy 8. It works well and the sound files for the Sherman are included in the sound library. It can play several sounds at the same time. These sounds can also be programmed to different switches on the transmitter.

Stephen White has a thread (My Beat Aussie Cent) in which he describes how he integrated a USM-RC-2 in his Centurion. I learned a lot form his work. He has fantastic plans with all the cabling in this thread. Het combines the Beier with the Red boxes.