Soliloqueen's k87(k67) and k47 capsules

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I'll take a listen to this in a bit, for better or worse, the flat k47 is flat. In real life certain frequencies get accentuated with closeness and vice versa with distance and the regular k47 is designed to maintain mid-presence in close range where The response itself would normally become u-shaped. I would suggest micing the flat 47 further. The mids might sound a bit hollow up close but for the very same reason I think they wouldn't sound overwhelming or stacked on top of each other in a live space at a distance like what may happen with the regular k47. If you want to use the flat k47 for close micing I would suggest a tube that rolls off both ends a bit and puts some bite into that region. This is probably why the 800 sounds so good with it? But I'm just spitballing
 
What's kind of funny though is that the frequency response of the typical k47 is almost exactly the difference between male and female hearing thresholds. What a lot of you guys hear as a pleasant bump in the upper mids or a neutral sound overall I hear as it being unbearably tinny because my hearing response is up about 4DB in that area from yours. Sometimes I wonder if flat 47 sounds to me like what you guys hear when you hear the regular 47...

I will say, If we're talking flaws, to me the flat 47 is a little overextended in the high end. I think If I were to redesign it I would probably shelve everything above 5K down just slightly to compensate for the lack of bump. I am somewhat interested in trying the same tuning changes on an accurate backplate to see what happens. That's going to be one of my first experiments when the accurate backplates get done. I'm thinking about offering two tunings of the production k47 and then continuing to offer this prototype as an additional product at a reduced price later, but that's pretty far off in the future now. Right now I'm working on bringing out the k87.
 
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I bought another Miktek CV4. The first one I have has a BN K7 in it. I will put the Flat 47 in the new mic once it arrives. I will then do a few tests. That might give us a better indication of the differences. I do really like Ben's K7 capsule. I think it's every bit as good as a Thiersch Red, which I also have. Might take a couple weeks due to the holidays for me to make the capsule swap but I will post something when I get it done.
In my case, I'm looking for NO mid-bump. I want to use it on violin. A U47 has a bit too much mid bite for my liking on violin. I've been using a Beyerdynamic MC930. It doesn't have a mid bump but has a pretty open top end. Maybe the Flat 47 in a CV4 will be just the ticket.
 
I'll take a listen to this in a bit, for better or worse, the flat k47 is flat. In real life certain frequencies get accentuated with closeness and vice versa with distance and the regular k47 is designed to maintain mid-presence in close range where The response itself would normally become u-shaped. I would suggest micing the flat 47 further. The mids might sound a bit hollow up close but for the very same reason I think they wouldn't sound overwhelming or stacked on top of each other in a live space at a distance like what may happen with the regular k47. If you want to use the flat k47 for close micing I would suggest a tube that rolls off both ends a bit and puts some bite into that region. This is probably why the 800 sounds so good with it? But I'm just spitballing

The Royer Mod to the MXL was also, it should be said, presumably designed and tested with the stock capsule in mind… and the stock capsule was quite bright.

I’m really quite pleased with how this ended up. The mic could certainly be tweaked and refined around this capsule to optimize it into something even better, but I’m probably not going to be focusing further energies there at the moment—I just don’t need these mics to be better than they are right now.

One day I will try them on a nylon-string guitar—I could imagine them being quite good for that!

I’d also be curious to try them on toms, but since this mic doesn’t have a pad I’d probably overload them. I could always solder a 10dB pad in place, try it out, and if I like it just leave it there and use them only for loud sources
 
The Royer Mod to the MXL was also, it should be said, presumably designed and tested with the stock capsule in mind… and the stock capsule was quite bright.

I’m really quite pleased with how this ended up. The mic could certainly be tweaked and refined around this capsule to optimize it into something even better, but I’m probably not going to be focusing further energies there at the moment—I just don’t need these mics to be better than they are right now.

One day I will try them on a nylon-string guitar—I could imagine them being quite good for that!

I’d also be curious to try them on toms, but since this mic doesn’t have a pad I’d probably overload them. I could always solder a 10dB pad in place, try it out, and if I like it just leave it there and use them only for loud sources
it sounds to me like there's a HF attenuation in place, the flat k47 is supposed to be much brighter than this. was the original capsule a k67?
 
It was! A cardioid-only loose K67 interpretation, I think. Rear membrane had no sputtering.

Here’s the mic schematic. No de-emphasis is obvious to me, but perhaps notable is the slightly low B+ voltage?

Also can’t definitively speak to transformer bandwidth at these impedances

B63667AC-834C-4C18-A8E9-2464359665EF.gif
 
what's weird about this one is, like, take a look at this
Thiersch mic:
thiersch.png

royer flat k47 mic:
flatk47.png

Do you see those odd "bands" at 7k, 4.5k etc? or maybe better conceptualized as troughs between those areas, and then the high end cuts out suddenly and starts rolling off. No behavior like this in any other recordings of the k47. I think it might be the electronics or body acoustics. I'd love to hear the two capsules swapped. This is what I'm hearing as well, and it's funky sounding, but I didn't know how to describe it.
 
The two “stripes” makes me think headbasket acoustics, perhaps—or maybe some sort of anomaly from positioning the two headbaskets so closely together.

The top end roll-off isn’t as obvious to me visually, but i’m viewing on a phone
 
I will say, If we're talking flaws, to me the flat 47 is a little overextended in the high end. I think If I were to redesign it I would probably shelve everything above 5K down just slightly to compensate for the lack of bump.
That sounds like something I’d be in love with !!!
 
A bit of an apples-and-oranges test between:
  • U47 with Thiersch Blue Line, Telefunken EF800, AMI BV08
  • MXL Royer Mod with SQ Flat K47, Mullard 5840, Jensen DB/E
While I set up the test to be as equitable as possible--mics positioned head-to-head into identical channels (Seventh Circle N72s), gain matched and then normalized after recording to 99.5% (in an attempt to get equal loudness)--this is clearly not at all a fair fight for the capsules. The modded MXL is much more cost-conscious in every respect. Still, after the capsule swap I think it acquits itself remarkably well.

I hear some pretty interesting differences, but it's almost pointless to enumerate those. Too much is different between these two projects--circuit, tube, transformer, headbasket acoustics--to confidently attribute anything to the capsule design (much less the capsule quality).

What does stand out, for me, is that the modded MXL with flat K47 very much sounds like a microphone I'd use. It didn't sound like that with the stock MXL capsule.

Both mics sound good enough to allow me to hear the music before hearing the microphone (if that makes sense), which I think is the most important thing.
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Dreamsville by Hank Mancini from Peter Gunn. Who's the guitarist? Nice player.
 
currently have 11 flat k47s left. the factory is going on break soon so after that, might not have any until february. will have k87s in the meantime though. should have saved more of the profit, but i needed new hard drives for client files for my audio engineering job :ROFLMAO:
 
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