What measuring jig for Diy planar magnetic headphones ?

[Joppe Peelen]

Hi i once made a planar magnetic headphone (from old sennheiser parts) on my youtube channel as a one day build (became 3 day build) And i measured it with my isemcon mic and some cardboard... not ideal but better then nothing here a pic (dont mind db calibration)

I might want to make a future project , making a planar headphone, with the stuff i learned over the years. and maybe make a nicer one.
here is the the complete video by the way fo those interested.

Feel free to skip all the intro crap ... feel free to skip anything actually

now my question is i dont have money for one of those graz fixtures but the next best thing i can come up with is the minidsp ears.. but i had the Umik 1 from them and was very disappointed in the noise and the capability of it measuring distortion, anyone know if the ears are more reveling ? i mean can i measure 0.1% or less distoriton. else it would not make sense to buy one.

Kind regards Joppe

 

[oratory1990]

If you just want to measure this specific headphone, you can send it over to me and I'll measure it for you

 

[Joppe Peelen]

If you just want to measure this specific headphone, you can send it over to me and I'll measure it for you

Well thank you for the offer, but measuring it is only usefull to make improvements. in this case i wont be improving this monstrosity haha. i might make a new one or start with one driver and measuring it might be usefull along the way. and change things etc.

 

[ADU]

Some people will just measure in their own ears, if they don't have the $$ to buy or construct a jig, Joppe. That is probably a better idea, imo, than trying to build something from scratch.

If you have some decent speakers in a room as well, then you can also use the in-ear response of those from your own ears for comparison, or as a rough guide or target for the headphone's in-ear response curve. If you want to improve the accuracy and reliability of this arrangement, I can give you some add'l suggestions on how to accomplish that as well.

If you do have the $$ to buy a rig, then I'd suggest trying to get one that includes a mannikin or some kind of head and torso, so you can use the system to do more reliable in-ear measurements of both speakers in a room, and your headphones. So you can compare the responses of the two. A system based on the new 5128 coupler developed by HBK would probably be best at the moment. Though the other rig manufacturers will probably be coming out with their own new updated systems to better compete with this new system. And the mannikin that HBK was offering with their new 5128 ear coupler seemed to have some potential issues with leakage, which might still need some sorting out. Perhaps there is already a fix for that though. (?)

The new HBK system can also run into quite a few $$. And I believe I also heard Crin talking about a cheaper Asian version or knockoff of this new system that he may be using in a recent livestream with Resolve. So perhaps that might also be worth investigating. (Though I'm not really sure what's up with that, and would be somewhat cautious about dealing with foreign vendors that may be offering knockoff systems like this.)

I have the feeling that most of the professional reviewers and graphers will eventually be moving away from the older flat plate systems, like the GRAS 45C, which are based on the 711 coupler. Because they are just not as flexible or reliable for doing in-ear measurements on both headphones and also loudspeakers as a system with a mannikin, or head and torso. (Both Crin and Resolve seemed to be making some noises, or at least intimating that they might have some interest in possibly moving a bit more in that direction in the above livestream.... Or so it seemed to me from some of their comments.)

I'm sorry I don't know much about some of the other lower-cost in-ear measurement systems that alot of folks seem to use, like the MiniDSP Ears, for example.

 

[Vini darko]

Hi Joppe here's a link to @solderdude website diy audio heaven. Scroll down to near the bottom for info about his diy measurment rig. I usually referance his measurments when shopping for headphones.

measurements

home back to headphones updated: Mar-02-2024 A set of measurements is just a tool which can be part of an evaluation of a headphone. My measurements are made with imperfect (and cheap) microphones …

diyaudioheaven.wordpress.com

 

[MRC01]

The MiniDSP EARS does most what you need for about $250. It's not as accurate as the GRAS that Amir uses, but at less than 1/10 the price it has a lot of value for what you get.
I posted some measurements made with the MiniDSP EARS, check it out and see if it would be useful.

 

[solderdude]

Hi Joppe here's a link to @solderdude website diy audio heaven. Scroll down to near the bottom for info about his diy measurment rig. I usually referance his measurments when shopping for headphones.

measurements

home back to headphones updated: Mar-02-2024 A set of measurements is just a tool which can be part of an evaluation of a headphone. My measurements are made with imperfect (and cheap) microphones …

diyaudioheaven.wordpress.com

And I live about 30km away from @Joppe Peelen
The rig has been slightly modified (angled) and a second mic has been added.

The MiniDSP EARS does most what you need for about $250. It's not as accurate as the GRAS that Amir uses, but at less than 1/10 the price it has a lot of value for what you get.
I posted some measurements made with the MiniDSP EARS, check it out and see if it would be useful.

Better to use the compensation from SBAF. The original is a bit 'off'.

 

[Joppe Peelen]

And I live about 30km away from @Joppe Peelen
The rig has been slightly modified (angled) and a second mic has been added.



Better to use the compensation from SBAF. The original is a bit 'off'.

OOh i did not know. we already might know each other under a different name haha, that happens in this world wow there is much info on your site. ! cant find the jig though?

I would really really really really hope amir wants to measure the mini dsp Ears once as one of his videos, and calibrate it to his GRaz, and share the cal files for rew (so measure the minidsp with cal, to the gras create new cal. this way it should be possible to calibrate our headphones by loading our cal and the graz cal (combine them)) it might get us as close as possible for the 1/10th price

so by the looks of it its either diy, or minidsp ears. i guess it will be the ears


thanks for the input so far !!

 

[solderdude]

cant find the jig though?

measurements

home back to headphones updated: Mar-02-2024 A set of measurements is just a tool which can be part of an evaluation of a headphone. My measurements are made with imperfect (and cheap) microphones …

diyaudioheaven.wordpress.com

near the bottom of the page.

 

[Joppe Peelen]

measurements

home back to headphones updated: Mar-02-2024 A set of measurements is just a tool which can be part of an evaluation of a headphone. My measurements are made with imperfect (and cheap) microphones …

diyaudioheaven.wordpress.com

near the bottom of the page.

Thanks ! gone do some reading

 

[freddi]

here's a 50 cent rig made of pink foam board with a steak knife - if the bottom foam board were large enough to support the mic then the insertion hole might not wear out so fast from the foam being compressed. For some reason I thought ScotchBrite might "de-Q" things by being a leaky gasket (that's a trick from the late Dr. Bruce Edgar when using some cone drivers on horns) - the drop off is wild with Koss Pro 4AA.