Soliloqueen's k87(k67) and k47 capsules

[Paul W]

Hasn't really to do with this exact k47. This headbasket of these dimensions creates a dip in high midrange, not typical for k47 based mics. Not at that exact frequency. But on the other hand the same happens with k87. However, in combination with just right capsule, maybe even stock one you get c800g kind of vibe. But if you go for u87 sound that headbasket won't work either.

Any thoughts on the MXL 990 body and headbasket? I noticed that on the Microphone Parts page about MXL 990 mods, they recommend their RK47 capsule, and while they have a more Neumannish-looking headbasket they sell for it, they call that a "cosmetic upgrade," which suggests to me that it doesn't make the mic sound more U47-ish.

 

[kingkorg]

Any thoughts on the MXL 990 body and headbasket? I noticed that on the Microphone Parts page about MXL 990 mods, they recommend their RK47 capsule, and while they have a more Neumannish-looking headbasket they sell for it, they call that a "cosmetic upgrade," which suggests to me that it doesn't make the mic sound more U47-ish.

I haven't tested MXL990, but several other mics with that headbasket type, and they don't seem to impact sound much. So i would agree u87 headbasket type would be cosmetic upgrade, as it is also supposed to be transparent.

Headbaskets are no different than room the mic is in. Any obstacle will cause reflection. That reflection will either cause a dip, or a bump, usually both somewhere in the response. Upper midrange for the most part. The frequency of these is dependent on distance of the obstacle. There is also the base under the capsule that causes reflections in u47. So it gets complicated. To nail a certain sound you need the capsule to be placed at exact height, and all the obstacles to be placed right in respect to the capsule. The size of the obstacles matter as well.

TLDR version, it's not about headbasket type, it's about exact relationship between reflective surfaces. That's why i say transparent mics are easy, you "just" avoid reflections, with something like 47 they have to be tuned.

https://groupdiy.com/threads/effect-of-capsule-height-in-head-basket.84530/post-1097866

 

[micolas]

IMHO i wouldn't touch those mics, leave them as they are. Headbasket is fine.

...but if I turn the monster into a
Franken-monster?
With the original k87, I like low-mids, mid-mids and high mids. (I like the mellow character of the voices of the 70s)
I've always had an inner conviction that the lollipop-style headbasket is not what I'm looking for, while the U87i (with its specific internal micro-acoustics) can lead me there. If I make CS1 a U87 style headbasket?
(aesthetically it would be very ugly )

 

[mrgrooves666]

I put flat 47's to a pair of B3, without any other adjustment, and for me it was a great improvement. Never liked the very british 797 capsules in those mics, they were very bright, for those mics..

 

[micolas]

I put flat 47's to a pair of B3, without any other adjustment, and for me it was a great improvement. Never liked the very british 797 capsules in those mics, they were very bright, for those mics..

Hi,
In what sense, improvement?
I'm going to put a cheap k47 in the SP B1 stock, found in the capsule box, and see what happens

 

[mrgrooves666]

For me mics became much more usefull for all sort of applications. I prefered to add HF boost myself if needed via EQ of my choice. Consider that cheap asia k47 can still have disgusting, extended 5k peak. For example I really dislike mic parts' K47. So for me it was particularly Ari's flatter k47 that brought those mics to something much more useful, to me at least..

 

[micolas]

For me mics became much more usefull for all sort of applications. I prefered to add HF boost myself if needed via EQ of my choice. Consider that cheap asia k47 can still have disgusting, extended 5k peak. For example I really dislike mic parts' K47. So for me it was particularly Ari's flatter k47 that brought those mics to something much more useful, to me at least..

Exactly. I prefer the same concept. Flatter, more versatile, picks up EQ well.
But could the 5kHz peak be attenuated by the headbasket shape of the B3 or B1?

 

[mrgrooves666]

Exactly. I prefer the same concept. Flatter, more versatile, picks up EQ well.
But could the 5kHz peak be attenuated by the headbasket shape of the B3 or B1?

I wouldn't think to that extent, but try it.

 

[JohnnyM]

I haven't tested MXL990, but several other mics with that headbasket type, and they don't seem to impact sound much. So i would agree u87 headbasket type would be cosmetic upgrade, as it is also supposed to be transparent.

Headbaskets are no different than room the mic is in. Any obstacle will cause reflection. That reflection will either cause a dip, or a bump, usually both somewhere in the response. Upper midrange for the most part. The frequency of these is dependent on distance of the obstacle. There is also the base under the capsule that causes reflections in u47. So it gets complicated. To nail a certain sound you need the capsule to be placed at exact height, and all the obstacles to be placed right in respect to the capsule. The size of the obstacles matter as well.

TLDR version, it's not about headbasket type, it's about exact relationship between reflective surfaces. That's why i say transparent mics are easy, you "just" avoid reflections, with something like 47 they have to be tuned.

Weirdly I did this exact experiment the other day, although my testing rig is more of a caveman setup than what you guys do

I have an mxl990, with the micparts 990xf circuit kit waiting to go into it when the flat k47s arrive. What I was able to do while I wait is compare the stock headbasket with the micparts headbasket. Intending do them do the same with just the capsule swap, then the capsule + circuit kit.

The rig is just some clean guitar DI’s revamped through a modified Princeton with the mic 12” away with all settings otherwise identical. I can post audio clips if they’re of use and not too off topic, if not I can wait till the whole experiment is done.

My initial impression was, from both a listening perspective and the frequency response graph, is the difference is microscopic at best

 

[micolas]

What I was able to do while I wait is compare the stock headbasket with the micparts headbasket.

My initial impression was, from both a listening perspective and the frequency response graph, is the difference is microscopic at best

Could you somehow do some tests/recordings with pink noise under identical conditions, possibly a null test?

 

[JohnnyM]

Could you somehow do some tests/recordings with pink noise under identical conditions, possibly a null test?

If someone could guide my idiot brain through how to do it, I’d be happy to. I’m assuming just a pink noise sample out of the DI box, into the front of the amp then capture with the mic?

 

[safc19371973]

Since my name was mentioned in this thread I'll clarify.
The O.P.R 87 U-mod (now discontinued) is not the same mic as my O.P.R Plan 8 Ultra(formally known as the O.P.R U87 1:1 clone)
They have totally different circuit and capsule. The 87 U-mod has a Chinese capsule which sounds pretty good for the price point. The Plan 8 Ultra capsule is made in 100% made in house and sounds
accurate to older 70's units upon which it's modeled.

The OPR UMOD in my opinion is the best mic I bought for the money. And this mic certainly was used as a control to where off the shelf mics sat for their worth in many comparisons..l..... (IN which it won). I believe Mr OPR got the most out of that microphone and really does do brilliant work.... I will never sell that Umod.. I will also say that every time I have contacted OPR it has been a pleasurably experience. I would love to come back and buy from your top shelf as I know they will not disappoint...... You got the most out of that Chinese capsule and for the price point I paid it was and continues now to be unbelievable value for money.

 

[micolas]

If someone could guide my idiot brain through how to do it, I’d be happy to. I’m assuming just a pink noise sample out of the DI box, into the front of the amp then capture with the mic?

if you don't have a studio monitor flatter than a guitar combo, then inject pink noise into it (directly, without DI box if you want), from a smartphone, laptop, etc.
The microphone must remain exactly in the same position for all measurements, a few mm really do matter.
Record the mic with the stock headbasket, then with the micparts supplied headbasket
in the DAW you use. One of the tracks, shift it out of phase by 180°.
On playback, only the difference between the recordings will be heard. In principle, this is the null test. Export and post for us to hear.
You can also use the method described by kingkorg, using pink noise and the CurveEq (Voxengo) plugin, you will see the differences very accurately, graphically. Make a print screen.
We are curious.
Do tests at 40..50cm from speaker to avoid the proximity effect and also at a few cm to highlight the differences when the proximity effect is manifested.
Don't forget to make all volumes equal in the DAW, for a correct analysis.

https://www.audiocheck.net/testtones_pinknoise.php

 

[micaddict]

Half my family is in the Netherlands. We are relatively recent immigrants. It's not off the table...

Tijd om thuis te komen Ariënne.

 

[john12ax7]

Anyone try a flat 47 in a Rode Classic I or II, or other bright tube mic? Would it just be a drop in replacement?

 

[JohnnyM]

if you don't have a studio monitor flatter than a guitar combo, then inject pink noise into it (directly, without DI box if you want), from a smartphone, laptop, etc.
The microphone must remain exactly in the same position for all measurements, a few mm really do matter.
Record the mic with the stock headbasket, then with the micparts supplied headbasket
in the DAW you use. One of the tracks, shift it out of phase by 180°.
On playback, only the difference between the recordings will be heard. In principle, this is the null test. Export and post for us to hear.
You can also use the method described by kingkorg, using pink noise and the CurveEq (Voxengo) plugin, you will see the differences very accurately, graphically. Make a print screen.
We are curious.
Do tests at 40..50cm from speaker to avoid the proximity effect and also at a few cm to highlight the differences when the proximity effect is manifested.
Don't forget to make all volumes equal in the DAW, for a correct analysis.

https://www.audiocheck.net/testtones_pinknoise.php

Sorry, I misunderstood, for some reason I thought you were asking for a pink noise test with the setup I’d already done to go alongside the audio examples. I do have studio monitors (amphion one15s) so when I get a spare moment I’ll do as you say and post it.

I don’t have curveEQ, I could probably do something similar with REQwizard or one of the handful of analyser plugins I have

 

[soliloqueen]

Anyone try a flat 47 in a Rode Classic I or II, or other bright tube mic? Would it just be a drop in replacement?

should be?

 

[micolas]

Consider that cheap asia k47 can still have disgusting, extended 5k peak. For example I really dislike mic parts' K47.

Would it be possible to use a LC notch filter (with lower Q - wider frequency range) for 5kHz to flatten the cheap asian k47?

 

[kingkorg]

Would it be possible to use a LC notch filter (with lower Q - wider frequency range) for 5kHz to flatten the cheap asian k47?

Absolutely, the post i made earlier today in the other thread. Just need to tune the circuit.

 

[micolas]

Absolutely, the post i made earlier today in the other thread. Just need to tune the circuit.

Will the LC notch filter introduce noticeable or negligible phase changes in the overall sound equation?
How much does the position of the LC filter in the audio chain influence (at the beginning, in the middle or at the end of the microphone circuit)?