Measurement Setups - Post Your Rig!

I have the ksc75 lying around somewhere, it'd be nice if we could compare our schlongs plots.

 

Am I the only one thinking this would make an awesome kit for people trying to get into measuring headphones and not wanting to throw together some hackjob with spare materials laying around but also not wanting to drop ridiculous amounts of money on a proper rig? It could be a BYO microphone setup, someone with a laser cutter handy could create the kits to sell.

I know I would sure as hell buy a kit.

 

I was just wondering what to do to use to start measuring, I like the Box Head, looks very nice, I've got an place to put it even! I'm currently looking to expand my desk area, make room for a larger Dac for starters

and then have a good place to put a measurement rig, useful info though guys, I picked up REW early today actually, I saw Thujone was having some luck using it. Though may I ask, aside from CSD plots, have we any info on how we measure our own Square waves

 

Alright for those of you who are tired of dealing with a 7" stick in the middle of your measurement rig but don't want to build up your own amp circuit and use a separate ADC like thew focusrite or something here is a simple way to take apart your Umik-1.

The first step is to remove the ring on the back. Ideally you would use small a pin spanner for this or a pair of circlip pliers would also work quite well. Unfortunately I didn't have either of these tools readily available so a safety pin in one of the holes pushing tangentially will do, just be careful not to slip.

Once you've got it moving it shouldn't be too tough.

At this point you can simply pull out the amp/ADC/USB board. There should be three wires soldered to it at the top. I managed to snap one them off in moving everything around, no worries though since they will have to be desoldered and resoldered anyway.

Now all that is left is to remove the mic capsule. To do this I just used a pair of vise-grips wrapped with some paper towels to prevent any marking. Just a little twisting should release the glue and then it should just pull right off.


Finally just desolder the wires from the board pull them through the body and solder it all back up. I also added some hot glue to the solder connection area to act as a bit of a strain relief and prevent the wires breaking off again.


Now you have a small mic capsule and a board to position in a more sensibly and realistically head sized enclosure.

 

haha, seeing this makes the $3 Panasonic mic alternative even better

Can you give us a pic of the capsule? I bet it's the same Omni mic

 

Bhahahahaa. Or. Bwhahahaha. "Boxhead 2.0 - Return of the shrunken head" here we come.

 

You get an SPL calibrated profile for the mic from these guys, though, that's worth something.

 

It's not very easy to get the capsule out without probably heating up the glue or having just the right sized cylinder to knock it out with and I don't really feel like heating up the capsule, wires and solder connections that much. I'm sure you are right and while I don't know that the SPL calibration is all that great since it is calibrated for the stick mic in free air it does at least give you some sense of the level at which you are testing your headphones if you are using REW calibrated. Also if you do go ahead and get a good quality external ADC you'll probably spend just as much although it will be more versatile. In the end I agree OJneg's method can be cheaper more versatile and deliver just as much performance but this is quite a bit simpler and if you don't already have an external ADC and don't want to use your onboard soundcard it's not really any more costly.

 

@feilb I can't wait to see what you come up with! That last design was really elegant and good looking. Hopefully I can come up with something half as good but chances are it'll just be another ball of tape and cardboard haha.

 

Alright so here are some pics of my new rig.



Headphone placement and alignment is now much easier also I think the pressure applied by the headband is more realistic.

 

Would something like the Dayton iMM6 (Dayton Audio iMM-6 Calibrated Measurement Microphone for iPhone, iPad Tablet and Android https://www.amazon.com/dp/B00ADR2B84/ref=cm_sw_r_cp_awd_beOTwbEFDWMY4) work to measure headphones? The smaller size is interesting...

 

the WM61A any good, or could I do better on a budget of 100$?

 

I put together a measurement rig. Details on the construction process in case it's interesting to anyone:

I ordered a MiniDSP UMIK-1 measurement mic and a USB cable with a 90-degree mini USB connector. I went to the hardware store and browsed and browsed and came home with:

• A 7" length of 4.5" outside diameter ABS pipe
• Some low-density open cell foam (had this lying around)
• Hot glue gun
• Some medium-density open cell foam (this stuff http://www.amazon.com/gp/product/B003VYAXV8)
• A few DVDs (had these lying around)
• A few sheets of felt
• Some Scotch spray adhesive

I cleaned up the ABS pipe.



I scuffed up the DVD, glued the medium-density foam to it, and then glued that to the ABS pipe. I added an ear-sized piece of foam over the medium-density foam.



I wrapped the measurement mic inside the low-density foam until I had a roll large enough to fit snugly inside the ABS pipe.



BOOM. Measurement rig done, for now anyway.



Questions to more knowledgeable heads:

1. Do I need to cover the non-business end of this with something solid? Currently it's open.
2. Do I mute the channel of the headphone that I'm not currently measuring to prevent it from interfering with the one that I am measuring?

 

Looks good, I'm concerned for the headband though!

 

Me too. I'll probably try cutting 3/8" or 1/2" off the end of the pipe to alleviate that. My concern was to prevent the USB cable from poking against the driver and it looks like the 90 degree connector allows me to shave a bit off the length while still doing that.

 

I had the same problem until ultrabike pointed out that my mic is Omni-directional (and so is yours!). You should be able to cut a sizeable amount off the end of the tube and angle your mic to accommodate the other side of the headphone. Doesn't look as pretty but it saves the headphones and gives good results.

 

I definitely thought about doing that, and may still do so. I appreciate the pointer. Do you have pics of your setup I could look at to visualize how the angled mic works?

 

I'll try to remember to snap a pic of the back when I get home. My overall build is on page 2 of this thread, though I realize you can't see the angle of the mic.