That is pretty much it. Granted, EC can make above average dynamic amps but electrostatics bring new challenges into play and even the small details start to matter quite a bit. Add to this the most resolving transducers money can buy and only the best will do.
Purrin pretty much covers it but with the SR-009 this design issue is a good thing. Think of it as two flawed designs coming together and masking each others issues. Muddy top end with bloated bass on the amp meets a bright headphone with bass limitations.
Thnaks for the info. I guess was lucky because I really like what I hear out of this combo.