Classe DR-15 amplifier compared to Classe Dr-9

I was a Classe dealer for many years and this is how I remember it:

The DR-15 was indeed designed by David Reich AND Glen Grue and was a class A/B amplifier. The DR-3, DR-8 and DR-9 were pure David Reich designs and pure class A. They had a darker, warmer, more mellow sound than thier class A/B brothers.

I had a pair of DR-8s running mono on a set of Apogee Stages and it was one of the most beautiful sounding systems I have evr heard.

Not sure if I would swap out a pair of DR-15s for DR-9s? I think it's probably a side step and not an upgrade per say.

The Classe DR-8 and 9 where not pure class A designs but a/b, the DR-3 was there only pure class A design. Had a DR-9 for many years and it was a fantastic amp, only bettered by the DR-3 and only if you had speakers which did not need large amounts of power.Great amp for Quad esl 57s. Sorry I can't answer your original question, just wanted to clarify the misinformation regarding the DR-8 and 9.

I found my Classe Twenty Five more dynamic and open than my Classe DR-25.

As Mofimadness suggested it may be a side step rather than an upgrade to replace the Dr-15's with DR-9's. I'm using the Dr-15's with Apogee Stages and a passive preamp. There appears to be a real synergy happening and I'm very pleased with the sound. I was told earlier that Jason Bloom used the Dr-15's in his development of the Stages though I can't confirm this. I think the Dr-15 was the last amp to contain Dave Reich's signature, alongside Glen Crue's. The speed issue I mentioned earlier has been noticed by other owners of DR amplifiers. I've been told it's a result of using four large capacitors instead of multiple smaller ones that Classe subsequently used.

Majicjazz...according to the brochure in my hand , the DR-8 and DR-9 WERE Class A amps up to about half their output,(70 and 90 watts), respectively then switched to Class A/B. Sorry for the confusion.