Hi!
Yesterday I decided to return to the stock configuration, after spending several days listening to the modded HD600.
I used denser foam on the back side of the driver. It reduced bass quantity slightly, balancing sound a bit, and it seemed to me the bass was a bit better defined.
That was using my DELL notebook, Sony receiver, Sony Minidisc deck and MD walkman as sources, without ANY amplification.
But, on 0 Ohm output impedance headphone amplifier, the bass was not as clean as before, and the change , or scaling for better sound, was not as pronounced, IMO.
The soundstage was little smaller and bass around 100 Hz developed additional small measurable - for me inaudible - harmonic distortions.
Now I returned foam mimicking the original one in shape, density, thickness and size back in place.
What a relief - my old HD600 are back, like meeting with an old friend again.
So this is my story trying to be smarter than the Sennheiser engineers, and deciding I'm not
Now I know, that acoustical damping is compromise, allowing better sound on lesser amps, or no amps, but limiting the level of SQ these headphones can achieve on good system with superior electrical damping.
The sad truth is, I spend almost no time using the big headphone amp, listening every evening from my MD walkman almost exclusively
Moonwalker
)
