Passive headphone correction filter for Beyerdynamics DT770 Pro 80 headphones

The Beyerdynamics DT770 Pro 80 headphones sound very good. However, the lower frequencies are emphasized which sometimes results in 'rattling'.

Solderdude from 'DIY Audio Heaven' was so kind to send me the details of a passive filter to suppress the lower frequencies. This has to be placed between the headphone amplifier output and the headphones. See DIY Audio Heaven.

I built the filter in a piece of PVC electrical conduit pipe. The photos largely speak for themselves I think:

just fits

one channel

soldered to the cable

showing the process of shoving the filter into the pipe

with a closeup

sealed with hot glue, but not air tight due to a ventilation hole

heat-shrink tubing applied, looks nicer

from left to right: PSU, filter, headphone amplifier

How does it sound? Definitely more neutral, lineair. Bass is not exaggerated anymore as was the intention and voices are more pronounced than without. I will keep the filter inserted, I like it.

If you built it let me know what you think - leave a comment, use the contact form or mail me: 

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