Four KM-84 Clones - Blind Test

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Did you tally up the votes?

(I didn't vote because they all sounded fine to my tin ears, but I'm curious how others ranked them.)
 
Did you tally up the votes?

(I didn't vote because they all sounded fine to my tin ears, but I'm curious how others ranked them.)
Edit: The goal of this “experiment” wasn’t to crown a winner or to say definitively which mic is the “best” but it was interesting to see how the KM-184 bubbled to the top.

Unofficially earlier today between here and YouTube comments it looked like this (for people who actually said they preferred one particular mic).
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Thank you joulupukki! The main takeaway for me is how similar these sound. On some sources I can't tell any difference, others I'm feeling certain I've identified some difference in frequency response but then second guess myself on listening again. Wild guess: I think D is the 184 and B is the micparts. I'd be happy with any of these mics but if I had to pick D feels the best to me, then C or A, then B.
That's pretty much exactly what I hear and think. I haven't read the answer yet. I think D is the much “bashed” KM184, which I know and appreciate very well.

Edit: pretty close to my expectations...Thank you joulupukki for this nice experiment! All microphones sound very similar, at least on youtube.
 
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who has bashed the km184 ?
Ohh, I've come across that quite often online in the last few years.(check gearslutz) The KM184 would be too sharp in the treble and only the KM84 would be the real deal and so on. I never understood that, I think they are very good and universal workhorses in the recording studio and also live on stage. I've worked with them myself for long years and I think you get a lot of microphone for the money. Very flexible.
 
I honestly hope the KM184 naysaying keeps up because it makes them a good buy on the used market.

I have my drumset right now with two KM184 overhead and a 421-II on the bass drum, which as the internet knows, is absolutely awful.

Myself I dont like the km184 that much compared to the km84, but its really more of getting a more likeable eq-curve from the start with the km84, nothing you cant eq to get the same in mix... if anyone would want :) imo
 
Myself I dont like the km184 that much compared to the km84, but its really more of getting a more likeable eq-curve from the start with the km84, nothing you cant eq to get the same in mix... if anyone would want :) imo
Well, the KM 84 is dead flat; doesn't have an "eq-curve".

Anyone who expected same from KM 184 was disappointed.
 
Well, the KM 84 is dead flat; doesn't have an "eq-curve".

Anyone who expected same from KM 184 was disappointed.
Im sure km184 is "dead flat" aswell, still dont sound the same, same with everything. The sonic differences is best described with eq curve in mind in terms of more mid, more highs, less low etc etc...
 
Yes, that's right.

Like the TLM103 (another “terrible” Neumann microphone ;) ), the KM184 has a built-in EQ curve, so it's practically ready to mix. In my opinion, this works quite well, you immediately get high-quality results, which can be very advantageous, especially in time-critical production environments (TV and radio broadcasts, VO and media productions). On the other hand, this can perhaps also stand in the way of one or other application, but in the end I don't think the differences are so great that an EQ couldn't fix them. YMMV.
 
Now that @Joulupikki has revealed the microphones, I'd like to chime in and tell you something about the KM84+ and KM84++. But first of all, I want to thank Joulupukki for the many hours he spent testing my PCBAs, all the interesting discussions we had, and making all the awesome recordings and Youtube videos since March this year. It was a great learning experience for both of us! But it was also good to receive comments from others, in this case from all those who dared to speak out and left their opinions in this thread or on Youtube. In some cases your comments supported what we experienced ourselves, and in other cases they didn't. Which is fine too. Many thanks to all!👏

Back to the KM84+, KM84++, and the Microphone-Parts SDC-84 as used in this blind test. I will not elaborate on all the technical details. This will be explained on my website later. I'll briefly summarize the differences and point out some points that I think could have influenced the sound of the microphones and might explain what you heard.

KM84+: Takstar CM-60 body with a 3U cardioid capsule and 3U GZT-84 transformer. Circuit design follows the legacy KM84 design, but most parts are in SMT, mainly 0805. Instead of the pad, which the CM-60 does not have, I added a low-cut filter with a jumper to select -12 dB/oct or -6 dB/oct roll-off. Most important for Joulupukki was the RFI filter that effectively suppresses cell phone interference. I expected this design to sound the closest to the KM84.

KM84++: Takstar CM-63 body with a 3U cardioid capsule and 3U GZT-84 transformer. In the KM84++ circuit, I set the JFET to a much higher bias current to achieve lower noise and distortion and a somewhat extended low-end. And I added a CMOS polarization voltage generator, also for higher SNR. Finally, it has a -20 dB pad switch that the KM84+/CM-60 does not have.

SDC-84: I don't know how close the SDC-84 follows the legacy KM84 design. But at least it has a different capsule and transformer than the KM84+/++. And in the mic used in this blind test, Joulupukki removed the feedback capacitor C2. That makes it more sensitive of course, but also affects the Frequency Response and distortion. I think this caused the edginess of this mic, which could be appropriate on, e.g. guitar.

Joulupukki recorded the FR charts of both the KM84+ and KM84++ using his monitor speakers, which are shown in the snapshot below. I aligned the charts at 1 kHz and applied 1/6 octave smoothing. As you can see from the graphs, the KM84++ has a tad bit more output at lower frequencies. But the major differences can be seen in the upper octaves. As both impedance converter designs are ruler-flat in the upper octaves, I assume the differences should be attributed to the different back chamber and slot designs of the CM-60 and CM-63 bodies. As far as I remember, @kingkorg pointed out the importance of the back chamber and slot designs on the FR and this would only confirm that. Despite the bumpy top-end of the KM84++/CM-63, there were quite some people who liked this one best, which came a bit as a surprise to me. Anyway, for this reason, I want to experiment some more with other nose cones to study their effect on the FR. And I'm also going to test the circuits in the Alctron T-02A, which is much more similar to the CM-60 and the MXL603 in terms of back chamber and baffle design. But one thing is for sure: the 3u capsules will remain in any case! These are really good and do not have that hyped high-end. And off-axis, they are also quite flat.

Jan
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