Capsule upgrade for Royer Mod/MXL 2001

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Nick92675

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Nov 10, 2018
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4
Hello all-
Many years ago, when the Royer mod came out I built it using the original kit he sold. I was never fully in love with it, as it sounded a little thin and bright to me, but it has been useful enough over the years to have around. Now I am interested in swapping capsules with some of todays more available options to see if I can get more out of it. Will the circuit support any K47, K12 or M7 capsule? Ultimately I'd like this mic to be used on female vocals. Is it as easy as asking myself, do I want this more "u47-ish" or "c12-ish" (knowing that the body/headbasket is different so I'm not expecting a proper clone - just a better mic than what I have now.) Has anyone done this specific pairing of changing the Royer circuit to a non K67 capsule with good results? Based on some reading here, it sounds like 797 or 3u might be my best bet for quality/value. Any other words of wisdom?
Thank you in advance!
 
There's no frequency compensation components / circuitry in the Royer mod, so if anything, it's meant for / better suited for non-K67 capsules. The circuit doesn't know and doesn't care what capsule is feeding it signal 🙂

No real shocker that a K67 capsule sounds thin / light on bass, with the massive peak in the mid-high frequencies (by design).
 
Use a darker capsule. I don't know much about 3U's M7, but their other capsules are pretty good sounding. I really like the one in the Warbler MKIV because it's darker than most edge terminated capsules.

Using a 797 capsule you'll likely not see too much of an improvement because most of their common large diaphragm capsules are K67s.
 
Excellent, thank you! And thanks for putting up with the noob questions - it is exciting to learn about this stuff. Gathering from other comments/threads/research I've done on the M7 - seems like the best route is emailing them directly to confirm it will fit in my body and the mount will fit. It'll be nice if I can turn this around, and if the M7/47'ish style works for this, maybe my next project would be some sort of C12 capsule... but lets not get ahead of ourselves.... it has taken me ~20 years to get to this point....
 
Excellent, thank you! And thanks for putting up with the noob questions - it is exciting to learn about this stuff. Gathering from other comments/threads/research I've done on the M7 - seems like the best route is emailing them directly to confirm it will fit in my body and the mount will fit. It'll be nice if I can turn this around, and if the M7/47'ish style works for this, maybe my next project would be some sort of C12 capsule... but lets not get ahead of ourselves.... it has taken me ~20 years to get to this point....
The only C12 capsule is a proper one like the original CK12, Beesneez CK12 (the one that's like $500 AUD), Tim Campbell's CT12, Eric Heisserman's HK12, OPR's CK12, etc. I believe Guosheng of 3U is working on one too (as in a proper one, not his edge terminated ones already out). Expect to pay $350 for a proper one. On a budget you could use one of 3U's, I prefer the darker Warbler MKIV capsule, or there's a good Chinese factory @soliloqueen works with that makes good capsules. Takstar also has an edge terminated capsule, keep in mind Chinese edge terminated capsules are actually modified K67 designs and not a CK12. What I like about Guosheng's Warbler MKIV capsule is that because it's darker than most edge terminated ones I feel like I'm not hearing air. Like literally. Listening to some CK12s and "CK12s" (by which I mean Chinese edge terminated K67s) I feel like you can hear the actual air near the mic, which I'm not really a fan of but at the same I like that scooped sound because it's IMHO less harsh sounding than a high shelf like the TLM103 has. I feel like Neumann actually nailed exactly what I'm looking for with their TLM107, which might be the only Neumann I want besides the U89i or TLM170, though I'm open to trying the Austrian Audio OC818 though I've heard of things like grille resonance and bad QC lately, the mics are supposed to be made to such a high tolerance they're all able to be used as matched pairs, but users on Gearspace have reported getting some that have half the output of another one or sound noticeably different. It's a shame because the dual output is a really cool feature that would be really useful for instrument recording. I don't really care about the proximity effect control because I can just roll that off or boost it with an EQ.

I wouldn't be opposed to having my CAD M179s grilles reshaped if anyone can do it and putting a CK12 capsule in them. Obviously cheap mics probably not worth modding but they already have all the polar patterns and a pad and low cut. The only issue is that the CAD M179 clearly isn't built to last, cause the rail of the headbasket seems to be plastic (because it's the only part of the headbasket that's black and it's also non-magnetic while the mesh is, and it runs alongside the whole body). I could be wrong and it could just be painted zinc or something.
 
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You can get a CK12 from AKG for just under $200. Wouldn't that be a "proper" "real" CK12, or are the modern variants too different than the original '50's/'60's designs be classed the same?
I mean the classic ones, but yeah, a modern C414 capsules can be found as replacement parts for under $200. They're very different from the older brass ring ones from back then. I actually quite like the teflon capsule from the C414 ULS as well. But newer C414 capsules are pretty different from the old brass ring ones. The flatter C414s like the ULS and XLS definitely have a place in a locker, and an XLII definitely does too if you want a really sparkly/airy high end. Personally I find that model to be a bit too bright, I don't know if I want to call it harsh, sibilant, or spitty, but on a lot of voices I feel it's close to one of those.

A lot of people building with CK12 capsules (or the Chinese edge terminated ones) are going after the old AKG sound from the C12 and first couple C414s because those mics are like $4000 or more (much more for a C12). Not that the ULS is bad for a flat mic, but the C414s with those capsules can be found for under $1000 (I've seen some only go for $500ish), and the current C414s are both easily available for like $800 or $900 and they're usually only $500~ used (I saw a lot for $400 before COVID), so there's no point in building with those capsules unless you really hate mics with surface mount components.
 
Well those teflon AKG capsules are not that bad and in the beginning of the G7 they were almost the only choice if you you were lucky enough to find one :)
They're definitely solid, if I were going for a utility mic without much character that would probably have been my capsule of choice, but Full Compass doesn't seem to carry them anymore. If gear prices drop a bit on the used market I'm definitely grabbing a C414 with a teflon capsule.
 
I mean the classic ones...a modern C414 capsules...They're very different from the older brass ring ones from back then.

I have not seen a page with a good, concise comparison of the different generations of CK12 capsules. If anyone knows of something like that I would appreciate a link.
 
Hello all-
Many years ago, when the Royer mod came out I built it using the original kit he sold. I was never fully in love with it, as it sounded a little thin and bright to me, but it has been useful enough over the years to have around. Now I am interested in swapping capsules with some of todays more available options to see if I can get more out of it. Will the circuit support any K47, K12 or M7 capsule? Ultimately I'd like this mic to be used on female vocals. Is it as easy as asking myself, do I want this more "u47-ish" or "c12-ish" (knowing that the body/headbasket is different so I'm not expecting a proper clone - just a better mic than what I have now.) Has anyone done this specific pairing of changing the Royer circuit to a non K67 capsule with good results? Based on some reading here, it sounds like 797 or 3u might be my best bet for quality/value. Any other words of wisdom?
Thank you in advance!
Try a 500pF at > than your B+voltage from plate to ground with your capsule before changing it
 
This would be almost impossible to pull off just because CK12 can be tuned (and used to be tuned) in tons of different ways, there is no "one" frequency or pattern response of CK12. Even the least expensive single sided variant used in c3000b can be tuned. They also vary in factory produced mics.

I have measured several brass CK12 capsules. They are all over the place, plus/minus 6db in different ranges.
 
This would be almost impossible to pull off just because CK12 can be tuned (and used to be tuned) in tons of different ways, there is no "one" frequency or pattern response of CK12. Even the least expensive single sided variant used in c3000b can be tuned. They also vary in factory produced mics.

I have measured several brass CK12 capsules. They are all over the place, plus/minus 6db in different ranges.
Is that 6 dB shifted from tuning? Like say +6 dB at 10K on one, but another is +6 dB at 15K?
 
Easily 0db vs +6db(or more) at 10K, and respectively 0db vs +6db at 50hz. The frequencies are fixed, the shape stays the same, boost amount changes. Pattern varies with frequency as well. All achieved just by tuning. It can easily be figured out by reading the Austrian Audio page i shared.

I have measured three currently made CK12 capsules, all made properly, yet they all measured and sounded so differently that most wouldn't even consider them the same type capsule.
 
Easily 0db vs +6db(or more) at 10K, and respectively 0db vs +6db at 50hz. The frequencies are fixed, the shape stays the same, boost amount changes. Pattern varies with frequency as well. All achieved just by tuning. It can easily be figured out by reading the Austrian Audio page i shared.

I have measured three currently made CK12 capsules, all made properly, yet they all measured and sounded so differently that most wouldn't even consider them the same type capsule.
someone should make a ck12 with screw thread between the halves like that tunable blue capsule
 
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