Post by BMF on Apr 19, 2013 13:15:19 GMT
Here's my guide. Do not use 'kibblefat's' phantom power supply because it has a bug. Use the other one designed by 'symphonic' (both are head-fi user names). It's cheap and easy to build.
docs.google.com/file/d/0B5ZWXtWdNv9UQVl3b1NORTZkY00/edit
For REW setup, see this Google Doc:
docs.google.com/file/d/0B5ZWXtWdNv9UZHhnTkNVUEtYaW8/edit
The Panasonic WM-61A electret mic capsule is cheap and it's easy to build using John Conover's method of re-flow soldering.
www.johncon.com/john/wm61a/
Keith
Edit: Looks like I used the wrong method for hyperlinks. I'll try to fix it later. Meanwhile, copy and paste the links into your browser.
When there is a lot of damping materials (wool, rockwool e.t.c.) in the cups a closed or opened port didn't seem to affect the lows anymore.
I also found that closing the port (no wool) has a distinctly different effect than stuffing it with wool.
In Jukes case (to get L and R to measure similar) I had to resort to closing the port on the 'bass heavy' side with a piece of felt (with the glue still on it) and using a certain amount of wool to lower the bass levels to where I want them.
On the other (bass light) driver side I had to do the same as described by Keith by taping felt over the bass port with a small 'gap' of a few mm cut out. Had to use less wool to make it the same as the other channel.
Till now (the few I have modded) mostly L and R cups were treated similarly and the amount of wool needed to get R and L differed only slightly. The end results was always close.
It is 'concerning' that replicating 'the trick' doesn't necessarily translate to even bass response even between L and R.
It is true that it will become flatter and better controlled.
To make one into reference material I suppose you really need to measure it.
Perhaps we could join forces in making (and supplying) cheap kits for measurements.
Thinking of a small 'plank' with a mic in it. On the backside it is connected to a simple fantom supply with a 9V battery clip and a wire with RCA plug.
Strap it on the earpiece with rubber bands.
Essentially what Keith makes but on a plank instead of an etymotic flange.
Also we can supply REW (or you can download that yourself) and we can provide a correction file for the 15kHz peak.
a full measurement kit for the price of a cheap headphone.
Takes the guessing out of it.
Perhaps make a thread for it or a tutorial on the the website.
Hermetically sealing it will be hard to do and is not recommended.
I know Luis (Paradox) claims his versions are hermetically sealed but acc to owners they are not.
You would also have to close the hole where the headbandwire enters and completely seal of the cable socket with a blob or something. Also the baffle port would need to be fully closed. and the edges of the baffle would need a sealant as well.
The membrane (if truly hermetically sealed) would be pushed inwards and outwards (like a barometer works) depending on the air pressure that day.
Of course you can completely close the port on the back completely and this will lower the bass (as in standard T40 opposite standard T20/T50) but the wool and anti reflection materials are better suited to 'control' the lows.
docs.google.com/file/d/0B5ZWXtWdNv9UQVl3b1NORTZkY00/edit
For REW setup, see this Google Doc:
docs.google.com/file/d/0B5ZWXtWdNv9UZHhnTkNVUEtYaW8/edit
The Panasonic WM-61A electret mic capsule is cheap and it's easy to build using John Conover's method of re-flow soldering.
www.johncon.com/john/wm61a/
Keith
Edit: Looks like I used the wrong method for hyperlinks. I'll try to fix it later. Meanwhile, copy and paste the links into your browser.
I am on the same page with this as keith is.
When there is a lot of damping materials (wool, rockwool e.t.c.) in the cups a closed or opened port didn't seem to affect the lows anymore.
I also found that closing the port (no wool) has a distinctly different effect than stuffing it with wool.
In Jukes case (to get L and R to measure similar) I had to resort to closing the port on the 'bass heavy' side with a piece of felt (with the glue still on it) and using a certain amount of wool to lower the bass levels to where I want them.
On the other (bass light) driver side I had to do the same as described by Keith by taping felt over the bass port with a small 'gap' of a few mm cut out. Had to use less wool to make it the same as the other channel.
Till now (the few I have modded) mostly L and R cups were treated similarly and the amount of wool needed to get R and L differed only slightly. The end results was always close.
It is 'concerning' that replicating 'the trick' doesn't necessarily translate to even bass response even between L and R.
It is true that it will become flatter and better controlled.
To make one into reference material I suppose you really need to measure it.
Perhaps we could join forces in making (and supplying) cheap kits for measurements.
Thinking of a small 'plank' with a mic in it. On the backside it is connected to a simple fantom supply with a 9V battery clip and a wire with RCA plug.
Strap it on the earpiece with rubber bands.
Essentially what Keith makes but on a plank instead of an etymotic flange.
Also we can supply REW (or you can download that yourself) and we can provide a correction file for the 15kHz peak.
a full measurement kit for the price of a cheap headphone.
Takes the guessing out of it.
Perhaps make a thread for it or a tutorial on the the website.
Hermetically sealing it will be hard to do and is not recommended.
I know Luis (Paradox) claims his versions are hermetically sealed but acc to owners they are not.
You would also have to close the hole where the headbandwire enters and completely seal of the cable socket with a blob or something. Also the baffle port would need to be fully closed. and the edges of the baffle would need a sealant as well.
The membrane (if truly hermetically sealed) would be pushed inwards and outwards (like a barometer works) depending on the air pressure that day.
Of course you can completely close the port on the back completely and this will lower the bass (as in standard T40 opposite standard T20/T50) but the wool and anti reflection materials are better suited to 'control' the lows.