22mm capsule

[Chrisfromthepast]

I've accumulated quite a few capsules for mxl603s, and the Banzai kit.
In an effort to come up with a few pairs of mics, I attempted some measurements.
I hope they are useful to someone. This Forum has given me so much, and my attempts to give back are not always the most graceful.
Here we go again.
These measurements were made 24 inches from a Genelec 8331, and 3" off axis from the center of the drivers.
The measurements were made on the same test setup, with 1 of 2 microphones, depending on the center pin depth of the capsule. The capsules are all 22mm screw on SDC capsules, which are either set at the mxl603s depth or the Banzai/Takstar cm60 depth.
As a means of comparison, here is a trace from an Audix measurement mic, from the same location.
1/48 oct smoothing.
Notice that there are room anomalies that will be present in all of the measurements.

 

[Chrisfromthepast]

I used the same Takstar cm60 to take all of the measurements for the less deep (0.05mm?) capsules.
I kept the mic in place and just screwed new capsules onto it, and double checked 24 inches. This mic was the best candidate because of the transformer-less circuit and relatively high quality threads for the capsules to attach to.
Here are 2 Takstar cm60 capsules

 

[Chrisfromthepast]

The Banzai 84 Maiku capsules fit this Takstar body. This is my best match of those from the third run.


The orange trace below is from the first run, and though I always found it quite dark, it works on snare. I hardly use the teal one

I gave away B as a gift, I'll measure it too if i get access.

 

[Chrisfromthepast]

The 603s capsules generally have poor quality threads.
I found some 22mm capsules at AliExpress that have nice threads, but completely different backplanes and grill than any of the others we have tested so far.
I found that the right depth for Takstar bodies was achieved by replacing the backplane with those from 603s capsules.
Here in green is a 603s diaphragm, spacer and backplane
in blue is the AliExpress diaphragm, 603s (thinner clear) spacer and 603s backplane
in orange is 603s diaphragm, AliExpress (thicker purple) spacer and 603s backplane

 

[Chrisfromthepast]

above and middle is AliExpress, below is the 603s.
Microphone modders on the internet have advised that mixed results can be achieved by grinding the front of the 603s grill, and moving the mesh part to the interior of the capsule. I tried that here with the AliExpress capsule with no notable results.

 

[Chrisfromthepast]

the rest of these tests are aken with a monoprice 600700 body, for capsules with a center pin that sticks out 3mm
The rest of the AliExpress capsules fit this form factor, lets start here

one decent match, and another amplitude match, and they all share the same WEIRD shape.

 

[Chrisfromthepast]

here are some omni capsules.
the green one is very substantial feeling in your hand, and works fine.
the blue is a stock 603s omni, and the brown is a capsule from a Badaxxe TK130, which was modified to fit these bodies.

 

[Chrisfromthepast]

The Blue trace is actually from that last group, its a nady cm90, which has the smaller pin depth and works great for a sax solo mic.
The grey line is a 603s supercardioid.
The green trace is one of the 603s capsules modified to make the face flat. it kind of works

When I was chasing the dragon of this mod, I sent one diaphragm to be reskinned by Luke Audio

 

[kingkorg]

Ok, can you upload all of this raw measurement data on a server and post a link? Name them properly, and i could try to use Audix file to generate compensated, absolute responses

 

[Chrisfromthepast]

Before I started opening up or grinding away at the capsules, I bought a few capsules from MicParts.com.
Having the capsule slits in addition to the body vents gives the pattern some strange lobes, so I can't use them in some situations.
These 3 are currently being used as 2 overheads and Hihat in my "oh shit I didn't know there was another opening act" workbox mic kit.
the mxl dip is still there, but quite tame

 

[Chrisfromthepast]

Ok, can you upload all of this raw measurement data on a server and post a link? Name them properly, and i could try to use Audix file to generate compensated, absolute responses

I hope this works!.
Im probably just 1 youtube video away from being able to accomplish this...

 

[kingkorg]

I hope this works!.
Im probably just 1 youtube video away from being able to accomplish this...

Also, is there a calibration file for your Audix mic?

 

[Chrisfromthepast]

I don’t have a calibration file, sorry

 

[kingkorg]

Sorry, i really tried but it didn't work. Not sure what happened with the timing reference and why it's different for all the measurements.

The point would be to use the response of the Audix as a calibration file for the rest of the measurements to get the absolute responses. But since the timing reference is off, Audix simply doesn't work for the rest of the measurements.

There are also these extremely sharp nulls, and they certainly can't some from the mics and capsules in this range. They should be at least in the same spot, but i see them wandering in different measurements. Not sure what they are.

In future, try not to use timing reference or loopback, just set output to the speaker, mic to the input, ant that's all. Use ASIO, not Java driver. Place the mics pointing directly to the center of the speaker as you are lucky to have coaxial drivers. 20-40cm distance, no more than that as you don't have anechoic chamber.


Thanks for the measurements anyways, they are insightful, to me at least.

 

[Icantthinkofaname]

the mxl dip is still there, but quite tame[/ATTACH]

But the Mic-Parts capsules don't have a dip! /s

 

[Chrisfromthepast]

The mic parts.com capsules dip at 7k just like the 603s capsules. They dip alot less, but all three of them do it.
Im a fan of these capsules, don’t get me wrong, but compared to a 451 or reference mic, they dip.

Sorry for the anomalies. Im interested in learning how to do this correctly, thanks for your patience Kingkorg.
My measurement experience is related to time alignment and tuning of large format sound systems. Getting a good, coherent phase trace at the sub crossover region is a different ballgame
In Smaart, we use a separate input and output for the reference, and treat the absolute time with a grain of salt because of the DSP.
REW isn’t really accepted in the live pro audio world, so I may not actually know how to use it.
I’ll read the manual and shoot these again when I have some downtime.

 

[Icantthinkofaname]

The mic parts.com capsules dip at 7k just like the 603s capsules. They dip alot less, but all three of them do it.
Im a fan of these capsules, don’t get me wrong, but compared to a 451 or reference mic, they dip.

Sorry for the anomalies. Im interested in learning how to do this correctly, thanks for your patience Kingkorg.
My measurement experience is related to time alignment and tuning of large format sound systems. Getting a good, coherent phase trace at the sub crossover region is a different ballgame
In Smaart, we use a separate input and output for the reference, and treat the absolute time with a grain of salt because of the DSP.
REW isn’t really accepted in the live pro audio world, so I may not actually know how to use it.
I’ll read the manual and shoot these again when I have some downtime.

Oh I'm just making fun of the fact that Matt from Mic-Parts said that there's no dip there in a thread because the smoothed measurements weren't showing one.

 

[Chrisfromthepast]

Oh I'm just making fun of the fact that Matt from Mic-Parts said that there's no dip there in a thread because the smoothed measurements weren't showing one.

Yeah…that thread and the banzai build thread are entertaining.
SDC capsules is a rich subject, and so unsexy compared to a U47 we are kind of stuck with mediocre options.
I dream of someone designing a honeycomb backplane for DIYers. The shell, spacers, and diaphragm of these ali express capsules seem a fine starting point.
Warts and all, mic-parts is still the flattest one I know about.
I am looking forward to trying out some of the gzt capsules in the next month. I hope they’re cool. Because GZT sells both depths, the Banzai 84 users can get some variety too.

 

[kingkorg]

I got intrigued by your measurements, and what caused some issues with these. You have some crazy stuff going on in marked range. Noise? Something resonating in this range. You kept it quiet during the measurements? Speakers were playing at reasonable volume?

 

[Chrisfromthepast]

I had to stop sweeping at one point because of a table saw in an adjacent warehouse.
I thought all of those were thrown out, as the noise floor before the chirp seems important.
The graphic you’re showing seems to suggest all was quiet at the beginning of the chirp, but there was ambient noise at the end.
I don’t want to muddy the waters with bad data.
I’ll try again at 20cm. I was having trouble getting a good reading up close and attributed this to not understanding the drawbacks of this 3 way coaxial speaker, but maybe I missed something else.
Speakers were as loud as they go without audible distortion.