weiss

AA CM87 comparison high frequency, normal?
« on: November 05, 2019, 08:04:11 PM »
I recorded a singer today with a Brauner Panthera. Just out of fun i compared the recordings with the Advanced Audio CM87 which i almost never used before. It sounds like if there was a blanket on the microphone. The high end seems pretty damped. Didn't expect it to be such a big difference ? I know it's not a fair comparison price wise but still  :o

https://www.dropbox.com/s/m4s0k41k9iifg8a/audio1.wav?dl=0
https://www.dropbox.com/s/svxyb2qbyswqz92/audio2.wav?dl=0


Re: AA CM87 comparison high frequency, normal?
« Reply #1 on: November 05, 2019, 08:38:46 PM »
One man's dull is another mans warm, one man's blanket of the mic is another man's harsh.
AA being u87 inspired should have attenuated highs compared to Brauner which has flat circuit and the same type of the capsule without attenuation. I bet with some very basic EQing the two would match to the point of being indistinguishable, and the price difference in sound would melt down.

weiss

Re: AA CM87 comparison high frequency, normal?
« Reply #2 on: November 05, 2019, 09:45:29 PM »
One man's dull is another mans warm, one man's blanket of the mic is another man's harsh.
AA being u87 inspired should have attenuated highs compared to Brauner which has flat circuit and the same type of the capsule without attenuation. I bet with some very basic EQing the two would match to the point of being indistinguishable, and the price difference in sound would melt down.
Thanks for the explanation, makes total sense. I was just sceptical about the amount of attenuation.
I'm in no way experienced with mics so forgive the noob question.

Khron

Re: AA CM87 comparison high frequency, normal?
« Reply #3 on: November 05, 2019, 10:24:49 PM »
Two different mics sound different - no major surprise there ;)
Khron's Cave - Electronics - Audio - Teardowns - Mods - Repairs - Projects - Music - Rants - Shenanigans

Re: AA CM87 comparison high frequency, normal?
« Reply #4 on: November 06, 2019, 07:46:02 PM »
Thanks for the explanation, makes total sense. I was just sceptical about the amount of attenuation.
I'm in no way experienced with mics so forgive the noob question.

Not a noob question at all, most people don't really know the ''warmth'' of u87s comes from simple built in EQ curve.

I think it's a good thing to have two that different mics. A lot of u87 clones don't nail that sound, AA know their stuff, so i would keep it as is for variety.

weiss

Re: AA CM87 comparison high frequency, normal?
« Reply #5 on: November 06, 2019, 08:08:03 PM »
Not a noob question at all, most people don't really know the ''warmth'' of u87s comes from simple built in EQ curve.

I think it's a good thing to have two that different mics. A lot of u87 clones don't nail that sound, AA know their stuff, so i would keep it as is for variety.

Yeah absolutely! Can be very handy with harsher sounding signals.

Re: AA CM87 comparison high frequency, normal?
« Reply #6 on: November 07, 2019, 03:10:06 AM »
I like the second mic waaaay better. I'm guessing this one is the CM87? With about 4 dB of EQ at the 10,000-20,000 Hz I'm getting a similar but fuller sound to the first mic. Getting the brightness without sounding too sparkly or thin. Adding +4 dB from 5k up gets a really close sound to the first mic (including the sparkly/breathy sound I found harsh), at least to my ears through the default Audacity equalizer. I get you weren't really asking for opinions but I really like mic 2 waaaay better, so much that I wouldn't even consider mic 1, so if mic 2 is the CM87 it's definitely a keeper. Applying the same EQ settings but inverted makes mic 1 sound like mic 2, so I'd pick mic 2 and just EQ it to get the desired results.
I recorded a singer today with a Brauner Panthera. Just out of fun i compared the recordings with the Advanced Audio CM87 which i almost never used before. It sounds like if there was a blanket on the microphone. The high end seems pretty damped. Didn't expect it to be such a big difference ? I know it's not a fair comparison price wise but still  :o

https://www.dropbox.com/s/m4s0k41k9iifg8a/audio1.wav?dl=0
https://www.dropbox.com/s/svxyb2qbyswqz92/audio2.wav?dl=0
EDIT: Actually relistening to the sample I heard (linked below), the CM87 is cleaner than I remember, though I still prefer the AT4047 or U87 on the source. Of course my voice is different from that voice, so who knows what I'd prefer in person?

Maybe the samples I've heard of the AA CM87 were either a bad mic, or I don't like the U87 sound, but I like the U87s I've heard. I prefer a U87 over an AT4050 based on recordings I've heard, so I find it weird on the AA CM87 samples where an AT4047 was also I used I prefered the later. I know the one sample where I prefer the 4047 the CM87 was an older one that had a round grille, so I'm sure that had some effect on the sound as well. Maybe I'm an idiot and I just prefered the 4047 on that voice, it's this test from Microphone-Parts http://recordinghacks.com/2011/02/26/vo-shootout-u87-l36b-cm87-at4047mp/

I think the U87 and AT4047 here are best, they're certainly the most articulate, but I have a hunch these aren't all the same recording because the upward inflection on the word "line up" (rather at the beginning of the word up) recorded by those two mics isn't recorded by the Aseyer or CM87 mics.
« Last Edit: November 07, 2019, 04:32:37 AM by Icantthinkofaname »

weiss

Re: AA CM87 comparison high frequency, normal?
« Reply #7 on: November 07, 2019, 10:02:51 AM »
I like the second mic waaaay better. I'm guessing this one is the CM87? With about 4 dB of EQ at the 10,000-20,000 Hz I'm getting a similar but fuller sound to the first mic. Getting the brightness without sounding too sparkly or thin. Adding +4 dB from 5k up gets a really close sound to the first mic (including the sparkly/breathy sound I found harsh), at least to my ears through the default Audacity equalizer. I get you weren't really asking for opinions but I really like mic 2 waaaay better, so much that I wouldn't even consider mic 1, so if mic 2 is the CM87 it's definitely a keeper. Applying the same EQ settings but inverted makes mic 1 sound like mic 2, so I'd pick mic 2 and just EQ it to get the desired results.EDIT: Actually relistening to the sample I heard (linked below), the CM87 is cleaner than I remember, though I still prefer the AT4047 or U87 on the source. Of course my voice is different from that voice, so who knows what I'd prefer in person?

Maybe the samples I've heard of the AA CM87 were either a bad mic, or I don't like the U87 sound, but I like the U87s I've heard. I prefer a U87 over an AT4050 based on recordings I've heard, so I find it weird on the AA CM87 samples where an AT4047 was also I used I prefered the later. I know the one sample where I prefer the 4047 the CM87 was an older one that had a round grille, so I'm sure that had some effect on the sound as well. Maybe I'm an idiot and I just prefered the 4047 on that voice, it's this test from Microphone-Parts http://recordinghacks.com/2011/02/26/vo-shootout-u87-l36b-cm87-at4047mp/

I think the U87 and AT4047 here are best, they're certainly the most articulate, but I have a hunch these aren't all the same recording because the upward inflection on the word "line up" (rather at the beginning of the word up) recorded by those two mics isn't recorded by the Aseyer or CM87 mics.

Both recordings came straight from the interface without any eq. The second one is the Advanced Audio.
It comes really close to the panthera by matching with an eq. I'm definitely going to keep it.

Can you explain to me why it makes a difference when recording with a microphone that has a flat response curve compared to a duller sounding microphone with brightness added afterwards?

Thanks for the link, will check that out.

Re: AA CM87 comparison high frequency, normal?
« Reply #8 on: November 07, 2019, 10:21:27 AM »
Both recordings came straight from the interface without any eq. The second one is the Advanced Audio.
It comes really close to the panthera by matching with an eq. I'm definitely going to keep it.

Can you explain to me why it makes a difference when recording with a microphone that has a flat response curve compared to a duller sounding microphone with brightness added afterwards?

Thanks for the link, will check that out.
I don't think it really makes a difference either way, because you get the same or a very similar sound. It's just easier IMO to start flat and EQ it to be bright. In this specific case, I preferred the first EQ I did the the CM87 without boosting the 5k range because it sounded brighter without that kind if thin breathy sound I don't like. Of course you could always just cut that 5k region a few dB in post as well, and presumably you'd lose that same tone I don't like. Of course some voices might benefit from that sound, I just don't think yours does.

Of course my mics are all a bit bright as well. The flattest large diaphragm one I own would probably be the AT4050 which isn't without its presence boosts. I'm debating my next mic purchase being either a 3U Audio Warbler MKVID or the CM87, since both get the U87 style sound.

Re: AA CM87 comparison high frequency, normal?
« Reply #9 on: November 08, 2019, 05:44:27 PM »
It does make a difference noise wise. K67 capsule in u87 has naturally boosted high end, then "built in" eq shaves off that high end and with it that much noise. It's like dolby NR. Boost high end at input, and lower it at output. End result less noise introduced by circuit in between.

If you go into tube pre, heavily driven, that excessive high end will drive tubes differently than duller mic. No EQ can compensate for that later.

Other than that, it shouldn't make much difference sound wise.

Remember that older analog equipment don't have that exact curve, it is very broad attenuation, starting at about 2K, ending at about -6db 20K. So back in the day using eq with a mic that had flat circuit and k67 capsule would give way different results.

Another situation when i use u87 type of circuit is live, and i'll rather use a mic that is less bright, and use HF band on mixer to chase some anoying frequencies/boost something i miss, or de-ess rather than use it to compensate for bright capsule. I hope that makes sense.

Originally u87/u67 were mostly intended for broadcasting. So less noise compared to u47 because of that "built in eq". Without it the excessive high end would distort the radio signal.  U67 is even darker. While u87ai is brighter as they are no longer were interrested in distorting radio signals. In the end Klauss Heyne made his name by removing that part of circuit all together. Everyone thought a blanket was removed of the mic.

Eventually everyone wanted the vintage version of the mic as Pro Tools took over, and digital domain didn't lack high end as tape used to. So we are back at the begining. 

Anyway, you can really install a small switch to turn that "eq" on and off.
« Last Edit: November 08, 2019, 06:06:39 PM by kingkorg »


Re: AA CM87 comparison high frequency, normal? New
« Reply #10 on: November 09, 2019, 01:05:00 AM »
Not a noob question at all, most people don't really know the ''warmth'' of u87s comes from simple built in EQ curve.

I think it's a good thing to have two that different mics. A lot of u87 clones don't nail that sound, AA know their stuff, so i would keep it as is for variety.
I've seen people who claim to know their stuff deny it too. Of course people here, and Dave Thomas, Brian Fox, and a lot of other mic modders and boutique mic manufacturers have proven it's true.

People who think the U87 is warm just because of the way the capsule is made (which is the complete opposite of the truth, they're designed to have that rise in the high end) should try putting a K67 capsule in a flat circuit and see what happens. These same people are the ones who say you can't mod a Chinese mic or use a Chinese capsule with good results. Even though there are a few expensive mics using similar capsules (and I think it was you who mentioned how close the edge terminated 797 capsules are to a good K67 capsule).

Didn't mean to rant, but I agree it's not a noob question, since there are a lot of people who don't know it, and a couple modders will say that a capacitor or capsule swap won't do much, (probably so you have to pay for their mod service, stuff like that really bugs me, especially when people charge a few hundred bucks for the mods, but aren't exactly open to sharing what they change). I only know it because of the MXL V67G/2001 mods from when I had a V67G a couple years ago.
« Last Edit: November 09, 2019, 01:45:00 AM by Icantthinkofaname »


 

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