Hi all, I just wanted to convey my experience with this company In case you are considering buying something from them - I can tell you their customer service is excellent.
http://www.ngineering.com/index.htm
Ngineering produces all kinds of sound, lighting and other products. I purchased a “Cessna Fly Over” sound module (2 small boards and a speaker). sound is very realistic.
When i hooked it up and installed it on the layout the loud end of the sound loop caused the speaker to emit a squeeling/creaking sound.
On the phone they worked with me to try several different things and when they didn’t work I sent the wired up component (2 modules and a speaker) back and they began to test the modules. There were several communications over several days regarding what they were finding.
In the end it turns out I overheated a couple solder pads which damaged the electronics.
What impressed me was the ongoing communications and time they spent trying to help me.