Measurement Setups - Post Your Rig!

This is what I'm working with. Picked up the sponges per ultrabike and the mic per Marv. I grabbed some 4.5" PVC, lined the inside with AcoustiPack (leftover from T50RP mods), and I intend to cut and stuff the sponges inside. Also using a CD/foam for the coupler and possibly another CD with a larger hole to support the mic on the back end.

I'm still pretty worried about the amount of stress a headband will take in order to stretch completely over the mic, but it looks like everyone else seems pretty comfortable with stretching over their wand mics. Maybe I'll disassemble certain headphones in order to avoid the headband stress.

Anyway, in terms of content, I have some things that I feel might be interesting for the community. Solderdude was kind enough to supply a schematic for an 8kHz passive filter to accommodate Hifiman planars. I think these filters can be a useful tool for those that found the treble on the HE-4, HE-400, and HE-6 bothersome. Hopefully measurements reflect that. Also, I'd like to post incremental measurements when modding the HE-6. It seems to be a headphone that is consistently disregarded in stock form due to the mod hype, but maybe measurements will help reflect the effects of each mod and also the effects of each ear pad.

Overall, I'm just excited to have a way to measure headphones without sticking a mic in my ear -- I'll be comforted by having more consistency than that!

 

I can't tell you how excellent I think the drive for measurements by enthusiasts is. You guys are doing a great job of broadening the activity.

 

I agree with Tyll. Now we need a statistician to collect the data from the various sources and model it to see what can and can not be compared between measurement rigs. I look at trends but I wouldn't mind seeing more quantitative tinkering.

 

Up to about 10kHz your measurements very much look like the HD600s measure on my rig. I do not have the little peak around 6.5kHz, but that's about the only thing that differs.

 

Doh! I was way hung up on the assumption that they were mono-directional! Thanks, UB!

 

Thanks for the inspiration everyone. I ordered a mic last night. Lots of diy stuff to do when I get home in a few weeks.

 

Spent some time getting this rig up and running this weekend and I've been having quite a lot of fun with it! At this point, I don't know if I want to listen to headphones anymore, measuring will be good enough . I want to thank all the folks who shared their rigs so that I could completely copy them. No, seriously.

Anyway, I figured I'd share some quick measurements and I'd love to hear advice if anyone has any!

Some things I'm still a little unclear on:

1. The measured SPL for a headphone. For example, I've noticed several measurements online that have a different fundamental SPL for each speaker (R and L), let's say 90dB and 96dB. This changes the overall distortion characteristics a bit, as the speakers will distort more at higher SPL. Am I on the right track if I just try to make sure each speaker has a fundamental SPL of, say, 90dB? Then I can adjust input/output levels for each individual headphone to make sure each is measured at 90dB?

2. The waterfall plot is fairly self-explanatory but I've attached my "controls" for the waterfall. I don't want to end up confusing people by having more/less time slices, a lower noise floor, etc. I've noticed on changstar that most of Marv's measurements (especially with the V1 setup) have CSDs starting at 0dB and going to a -36dB floor. In REW this is just the same as measuring the highest point on the CSD and subtracting 36 to create the lower limit. Anyway, I feel comfortable with using this ~ -35dB noise floor but please feel free to give me some tips on the rest of the CSD parameters!

Okay, here are the measurements for my HD580:





CSD Parameters:

 

Any pics of your rig?

 

Still working on the stand

EDIT: Holy hell those pics are huge, whoooooops

 

Apparently with REW you don't need to calibrate your sound card when you're using a USB mic. Is it a safe assumption that I can use any amp/DAC combo so long as they provide consistency? So far I've only used my FiiO E17 to make measurements.

 

Does anyone know of a way to measure headphones after being run through some sort of EQ plugin?

 

You can set your capture program to record and then use a different program to generate the signal you need. For example, play PN in Jriver with the DSP suite enabled and use REW's RTA function to pick up the input.

 

I'll certainly consider it. I've already done 10+ measurements of HE-6 variations and, admittedly, I performed them back-to-back for consistency and didn't listen to each and every configuration. In other words, I would not be able to claim subjective impressions of each config. I also don't have the golden ears that some others have. Are short (general) subjective impressions adequate? I'd like to communicate my preferences, albeit not lingering on semantics. If that's all well and good, sign me up.

P.S. Should measurements regarding tweaks (mods, pad rolling, etc.) belong in the mod/tweak sub forum? This way the postings in the measurement sub forum can be focused on headphones in stock form?

 

Sounds good to me, I'm still working on refining my setup but am definitely game once I feel like I've got something pretty good and consistent.

 

Definitely keen to contribute but I'll hold off until I'm happy with my measurement system. I'm planning on making a few changes to see if I can get more reliable results.