Yes we can build a Synergy 240 into a stock Dyna St-150 chassis. The cost is $999 and includes new audio circuits, new output circuits using Exicon power mos-fets, and an internal new 4 channel regulated power supply board mounted on a new internal heatsink containing four high current high power transistors supplying regulated plus and minus supplies independently for each channel. Its a lot of work, uses a lot of expensive parts, but it turns the Dyna St-150 into an amazing 120W/Ch Synergy amplifier, using identical circuits as out big Synergy amps. We can do it with double die Exicons for an extra $100, but we consider that overkill for this application.
Frank Van Alstine