croak
R.I.P. 28 June 2021
- Joined
- Mar 28, 2007
- Messages
- 14,317
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- 942
I have enjoyed my HiFi Man 4xx for a while, my first planar magnetic headphones.
I bumped in to a thread about modifying them. Being open planar they send as much in to the ears as in to the room. I don?t listen softly so have had some complaints.
The modifications I read about were mostly about finding different dust filter cloth and metal mesh that allow easier air flow out the back of the capsules. I listened to them in ?naked? state by popping the rings and grids off and they are indeed better that way.
So more leakage in to the room.
That?s when I thought of Basotect foam. A modern acoustic absorption foam that?s very efficient. Thought I might absorb a bit and get closer to naked, as it?s in my opinion the reflections eliminated that make this difference. Manually bringing two blocks of basotect foam in to the naked cavities while listening showed little if any audible difference over naked, so was beginning to think my hunch had merit.
I cut some up.
Using the grids for some guidance.
However. I didn?t like this as it squashed the lead wires normally left to float in air up against the transducer grid. Thus I sliced the foam down it?s middle.
Now the wire is embedded in the foam.
Added some crescent moons to fill the gaps as it just didn?t look right with the two dark moons either side showing through the grid
And done.
Impressions so far of a more open and detailed sound that isn?t dark like the stock phones.
My crude measurements of leakage while headphone is on a Sieveking Omega stand done with a phone app placed at the headphone stand seem to show I have ?gained? or is that lost about 1.5 to 2 dB of leakage. No great shakes but an improvement with better sonics and dust protection maintained.
Totally reversible too which is nice.
I bumped in to a thread about modifying them. Being open planar they send as much in to the ears as in to the room. I don?t listen softly so have had some complaints.
The modifications I read about were mostly about finding different dust filter cloth and metal mesh that allow easier air flow out the back of the capsules. I listened to them in ?naked? state by popping the rings and grids off and they are indeed better that way.
So more leakage in to the room.
That?s when I thought of Basotect foam. A modern acoustic absorption foam that?s very efficient. Thought I might absorb a bit and get closer to naked, as it?s in my opinion the reflections eliminated that make this difference. Manually bringing two blocks of basotect foam in to the naked cavities while listening showed little if any audible difference over naked, so was beginning to think my hunch had merit.
I cut some up.
![d25857a71eb36cfd6b38c03c0fef05e4.jpg](https://proxy.imagearchive.com/6d0/6d086c8318348b00992b338884b0d2b9.jpg)
Using the grids for some guidance.
![751dc595ce3775f6583761c07b0d16a6.jpg](https://proxy.imagearchive.com/b17/b1716d94835284e1f1e73d90697ae866.jpg)
However. I didn?t like this as it squashed the lead wires normally left to float in air up against the transducer grid. Thus I sliced the foam down it?s middle.
![a597ea4eb3c6257c2a04493cb1b0ec08.jpg](https://proxy.imagearchive.com/8fd/8fdfac09d372b5030df124dd233778a0.jpg)
Now the wire is embedded in the foam.
Added some crescent moons to fill the gaps as it just didn?t look right with the two dark moons either side showing through the grid
![c8c40f933e42125966ddc3ffee58c442.jpg](https://proxy.imagearchive.com/a1f/a1f284bfb342e66561e918e0f3722e23.jpg)
![d8d639169d028c93ce38ba3fb374be05.jpg](https://proxy.imagearchive.com/a8a/a8a17c293df73ec4b028ad5698219401.jpg)
And done.
Impressions so far of a more open and detailed sound that isn?t dark like the stock phones.
My crude measurements of leakage while headphone is on a Sieveking Omega stand done with a phone app placed at the headphone stand seem to show I have ?gained? or is that lost about 1.5 to 2 dB of leakage. No great shakes but an improvement with better sonics and dust protection maintained.
Totally reversible too which is nice.