CD player - power amplifier direct connection

Hi,

I connect my old Sennheiser HD 530 II headphones (nominal impedance: 300 Ω, sensitivity at 1kHz: 94 db, power handling capacity: 200 mW) directly to the output RCAs of my CD/DVD/Blu-ray players via an adapter, as these players have not the headphones output. I cannot change the volume, but I find that it is always very good with both CDs and DVDs/BDs. By this minimal setting, I find that the headphones performance is very good.

I would like to try the direct connection between my Proceed PCD3 CD player and my Jeff Rowland Model One power amplifier by the use of balanced cables, so as to avoid the preamplifier device and - I imagine - to obtain higher performance from my ML Aerius. My Proceed CD player has not a volume control (I know that CD-player integrated volume controls commonly show very poor quality), but I presumed that, as for headphones, it would always be quite optimal (I have not audio volume problems in my house).

Some audio experts, however, have told me that this test would be very dangerous for the security of my system, but they have not clarified why...

May someone help me to understand the problem?

Thank you very much.

Luca