Classe DR-15 amplifier compared to Classe Dr-9

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.

If I remember rightly the DR-9 was designed as an A/B design to compete with DR-3s in sound without the high price tag of class A. The DR-15 is more of a Glen Grue designed amp using Dave Reichs signature as a selling feature.