Warm Audio WA-67 - Teardown

[Whoops]

So, slightly off topic..Will a real K-67 capsule fit this without a bunch of modifications..?

its been said in this thread the WA-67 circuit is exactly the same of the Neumann U67, only exception is the output capacitor which the WA uses an higher value than the original. But all the capsule de-emphasis circuit is exactly the same

 

[mhelin]

Hi mate,
Thanks for the photos, it’s clear in the photos that the 3U capsule is different.
So thank you so much for correcting us and thanks for the info.

Strange that Warm used 3U capsules in other mics and choose a different manufacturer for this mic.

what is AYM? What’s the background?
Never heard about them

They have web pages:
https://www.nbmic.com/aym-audio-about-ushttps://www.nbmic.com/microphone-capsules.html

 

[Whoops]

Thank you so much for the links.

did anyone already bought mics or capsules from them?
Do they sell direct?

 

[soliloqueen]

Thank you so much for the links.

did anyone already bought mics or capsules from them?
Do they sell direct?

they're good capsules. Their QC is really good. I would say they're similar to 797 in sound quality, and they cost about $20.

 

[kingkorg]

I would just be careful with their k47. It's not the question of quality, just that their upper mid-range is too pronounced and it can be quite sibilant even though the high end is just right. Good choice for something like U47 fet, but i'd never use it on acoustic guitars, vocals, overheads and such...

 

[soliloqueen]

I would just be careful with their k47. It's not the question of quality, just that their upper mid-range is too pronounced and it can be quite sibilant even though the high end is just right. Great choice for something like U47 fet, but i'd never use it on acoustic guitars, vocals, overheads and such...

the rk-47 is ugly IMO. I'm not sure why it sounds like that.

 

[Mworthin]

They're really old. They make the mic parts capsules. They used to be Tongxin. They built a new factory and upped their manufacturing quality considerably and they decided to rename the whole company after the new factory location.

You really know your capsules...do you have a brand other than Soliloqueen and are you selling your mics commercially?

 

[soliloqueen]

You really know your capsules...do you have a brand other than Soliloqueen and are you selling your mics commercially?

Soliloqueen isn't my brand! My brand is still in development. Some day soon I should be bringing an accurate K87 to the market, followed by a K47. I will probably not do a CK12. I would need to simplify the design (but keep it electrically/acoustically identical) to make it doable for me, and I don't want to invent that kind of design, have someone else steal it and blow a hole in a good portion of the CK12 market. I'm sure everyone who's made CK12s has thought of ways to make the design easier to manufacture without changing the sound, but none of us want to disrupt a market people rely on for income. I probably won't do an M7 either because I don't want to deal with the glue, but I will consider it if I invent a new way to secure the diaphragm that isn't rings or glue.

 

[Icantthinkofaname]

Yes it does at least look like 3U's modified backplate design, wouldn't know for sure for the rest of the capsule assembly.I think this mic must be missing usual demphasis part in the circuit, hence why they are "doing" it at the capsule level with 3U's modified backplates.. Some savings on extra components perhaps, the cost of capsule must be the same anyway...?

I believe the 3U capsules cost the same, or the dark version costs a bit extra. I question how well Warm can actually recreate a circuit when their WA-14 has 3 patterns, 3 way pad, and no low cut. I definitely wouldn't be surprised if they didn't implement something right or intentionally left something out intentionally for the sake of simplicity. Normally I'd say "who cares" to a creative liberty but they claim their designs are exact recreations.

Soliloqueen isn't my brand! My brand is still in development. Some day soon I should be bringing an accurate K87 to the market, followed by a K47. I will probably not do a CK12. I would need to simplify the design (but keep it electrically/acoustically identical) to make it doable for me, and I don't want to invent that kind of design, have someone else steal it and blow a hole in a good portion of the CK12 market. I'm sure everyone who's made CK12s has thought of ways to make the design easier to manufacture without changing the sound, but none of us want to disrupt a market people rely on for income. I probably won't do an M7 either because I don't want to deal with the glue, but I will consider it if I invent a new way to secure the diaphragm that isn't rings or glue.

I think I've seen quite a few capsule boutique capsule manufacturers say the same thing regarding CK12 construction. I definitely wouldn't want to see dirt cheap ones if it would put people out of business, but I think a still relatively expensive (compared to Chinese capsules) version could be a good thing. Nothing too low, maybe something like $250 or $275. I'm using Tim's capsule price as a baseline there. Or alternatively it could be useful for lower income markets or countries where their currency isn't strong. Though that's not really something independent operations need to worry about.

 

[kingkorg]

Im not sure if something like Austian Audio capsule would be a solution. However, i am still puzzled by their choice to leave the top of the grille closed. That's a big no, no! I hope i'll get my hands on one of those to try them out.

 

[Mworthin]

Im not sure if something like Austian Audio capsule would be a solution. However, i am still puzzled by their choice to leave the top of the grille closed. That's a big no, no! I hope i'll get my hands on one of those to try them out.

The OC818? It is a wonderful mic—I have a pair and they are my go-to for close micing piano. I like putting both diaphragms in separate channels and then using the PolarDesigner plug in in the DAW to make a complex pattern. If there is a problem with the grill, it isn’t obvious.

With the plug in, you can have, for instance, wide cardioid or Omni at the low end, cardioid or hypercardioid at the top end, as well as dial in how much proximity effect you want. I do that, notch filter out resonances with Fabfilter that pianos inevitably have and there is very little other EQing left to be done.

 

[Snatchman]

Thanks alot for your reply..!

 

[kingkorg]

The OC818? It is a wonderful mic—I have a pair and they are my go-to for close micing piano. I like putting both diaphragms in separate channels and then using the PolarDesigner plug in in the DAW to make a complex pattern. If there is a problem with the grill, it isn’t obvious.

With the plug in, you can have, for instance, wide cardioid or Omni at the low end, cardioid or hypercardioid at the top end, as well as dial in how much proximity effect you want. I do that, notch filter out resonances with Fabfilter that pianos inevitably have and there is very little other EQing left to be done.

That's why i said i'd like to test it myself. Since you have those, maybe you could make a recording of pink noise through your monitors in cardioid mode and post it here. Something like 20cm away from the speaker, mic placed halfway between the tweeter and woofer. If my guess is right, the mic should have at least 3db sharp notch in the upper midrange or lower high end. Which shouldn't be there.

 

[Icantthinkofaname]

its been said in this thread the WA-67 circuit is exactly the same of the Neumann U67, only exception is the output capacitor which the WA uses an higher value than the original. But all the capsule de-emphasis circuit is exactly the same

This has got to be a really poorly thought out mic then. I don't know how flat the dark K67 is, but I'm guessing way more high end is rolled off than is supposed to be due to the capsule.

 

[Mworthin]

That's why i said i'd like to test it myself. Since you have those, maybe you could make a recording of pink noise through your monitors in cardioid mode and post it here. Something like 20cm away from the speaker, mic placed halfway between the tweeter and woofer. If my guess is right, the mic should have at least 3db sharp notch in the upper midrange or lower high end. Which shouldn't be there.

I can do that. It will be through Genelec 8341As, which are calibrated to my room and are coaxial drivers.

 

[soliloqueen]

This has got to be a really poorly thought out mic then. I don't know how flat the dark K67 is, but I'm guessing way more high end is rolled off than is supposed to be due to the capsule.

it is indeed

 

[Mworthin]

I can do that. It will be through Genelec 8341As, which are calibrated to my room and are coaxial drivers.

OC818 recorded 20 cm from the monitor, recorded through a Metric Halo ULN-8 3D. I included a contemporaneously recorded source file for reference--basically the Logic Pro Pink noise generator was recorded to one channel of the Metric Halo session, and also ported to the 8341A, where it was picked up by the OC818. The OC818 was recorded to a separate WAV file and is slightly lower volume so you can tell the two apart (about -20 db vs -12 dB of the source). I don't have Spectrafoo on my computer any more, since it has not been updated to 64-bit and won't run on my machine, but it would be perfect for this comparison.

Also attached is a piano sample, a fragment to avoid any copyright issues.

 

[Mworthin]

OC818

Attached are photos that show how the capsule is suspended and the plate on top of the mic.

 

[kingkorg]

Wow, thank you for such a swift reply. Now, this is by no means accurate or reliable measurement, nor proof of anything, let alone i'm right. But only reason for this notch to be here is either the one i mentioned, or a fault with your tweeter or something in close proximity to it, which i doubt.

I would bet it is caused by the cover on the top of the grille. The notch is not typical for this type of mic/capsule.

This doesn't mean anything, and absolutelly not that the mic sounds bad! I would personally try to avoid that barrier if i was designing a mic. I believe the only reason it's there is to attach another oc818 to it.

Great piano samples, and the proof what i just rambled about doesn't necessarily mean anything.

 

[Mworthin]

Wow, thank you for such a swift reply. Now, this is by no means accurate or reliable measurement, nor proof of anything, let alone i'm right. But only reason for this notch to be here is either the one i mentioned, or a fault with your tweeter or something in close proximity to it, which i doubt.

I would bet it is caused by the cover on the top of the grille. The notch is not typical for this type of mic/capsule.

This doesn't mean anything, and absolutelly not that the mic sounds bad! I would personally try to avoid that barrier if i was designing a mic. I believe the only reason it's there is to attach another oc818 to it.

Great piano samples, and the proof what i just rambled about doesn't necessarily mean anything.

The only thing in proximity to the tweeter was the mic. I have a busy week ahead, so it was either now or ?, but a more scientific approach would be to vary the distance, use different monitors, parallel a measurement mic, etc.

The broad, flat top does make it easy to put two of the mics in XY, one inverted over the other. They are surprisingly heavy for their size.

It seems to me that every mic has some limitations, and you decide which ones you can live with. There is not much signal in a piano over 6000 Hz, so for this purpose, it isn’t an issue even if it were audible. I haven’t been able to DIY a piano mic that I really like, but I suspect it is because of the Chinese capsules I have had access to.