Grado SR-325 Custom Build ( w/ freq response change? )
Jun 2, 2021 at 8:36 PM Thread Starter Post #1 of 3


New Head-Fier
Oct 31, 2016
Finished product detachable cable mod ( pretty much the only stock part left on these is the drivers from the SR-325s.


I did some baseline measurements of the original 325 pair using grado style foam pads and a post mod test with the same pads. I noted a distinct shift in frequency response in the 1.4-3.4khz range.


This is right channel. The original is the earlier times, modified later times. As such the plateau is with the modified headphones.


Same shift is reflected on the Left channel for the most part.

I was honestly surprised to see that much of a change. These are open backed so I assumed the shape and material of the outter can wouldn't have that much of an impact. If anyone has any thoughts or learnings I'd love to know more. Fairly new to this level of modding and measurement testing. Advice is of course always appreciated. Judgement and Heckling is also appreciated when it's funny =P

More photos / videos and details are linked in imgur here: In case you want to dig deep.
Jun 3, 2021 at 11:26 AM Post #2 of 3
Try a semi-closed pad design and take some measurements. That large series of peaks in the 1k - 4kHz region is going to be ear-piercing! Closing the driver will help build up the bass, but using a semi-closed pad will help control the bass resonances.
Jun 3, 2021 at 3:07 PM Post #3 of 3
JOKER CANS! :beerchug:

Interesting results. I'd agree with NA Blur that the 1k to 4k peak is going to be undesirable for people with sensitive ears. That tends to be the area I need to EQ on "brighter" headphones. You may try lining the cup with felt and adding a bit of foam between the cups and your ears to see if that can get it under control. Also as NA said closing up the headphones can bring up the bass levels, but you'll have to listen to see if it's desirable.

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