Topic: sp cmc-4/sp cmc-8:what 's the best ?

[slowblow]

Hi there .
i m' newbie and i use md sharp and mic sony ecm 717.i need cardiod/hyper mic when i tape in large venue.
i have see in soundprofessionals cmc4 and 8 are available now.
anyone can help me to make a good choice 
i only tape in stealthy conditions.
thanks in advance,
slowblow

[thierryhenry]

They are mostly the same, rumors around the board is that the 4's have been known to clip and distort with extremely loud sounds. I have the 8's love them. If you are gonna spend the $200 already (for 4's at least), might want to spend the extra $30 and get the 8's, but it really doesn't matter.

[whaleywoo]

I have the SP CMC 4 and when they work they're beautiful but boy do they overload in high decibels.  I have made a couple of errors with them by misjudging the sound and generally try to attenuate using my Nomad's input volume settings.

By all account there's some modification that can be made.  Any one know of them?

[kfrinkle]

The CMC-8s overload in high SPL situations as well, FYI.  I was running CMC-8's > SP-SPSB-1 > JB3 for both Manson and Isis recently, and the Manson show had awful bass distortion, even though i had bass rolloff at 195 for that gig.  The Isis show has just a tad bit of high SPL distortion here and there.  Levels on JB3 never came close to overloading.  So be warned, it appears that both CMC-4s and CMC-8s will overload in high SPL situations.

[kfrinkle]

You have special CMC-8s, or I have retarded CMC-8s PG, i dont know who has what here.  Just my 2 cents on what is oging on with my pair, which i do take care of.

[jeffbr]

You have special CMC-8s, or I have retarded CMC-8s PG, i dont know who has what here.  Just my 2 cents on what is oging on with my pair, which i do take care of.

I had the exact problem last week at a Citizen Cope show. My levels were fine (actually a bit low),  but the bass was distorted running CMC-8's > SP-SPSB-1 (rolloff @ 95Hz) > JB3. I'd love to know how to avoid that in the future. I also have an SP Preamp that I'm going to try. I don't know how that will help, though.

[kfrinkle]

Jeff,

  I have the same fucking problem.  Half of me thinks it is the SP battery box.  I was using my small spsb-3 when I got distortion, so I am actually gonna be running spsb-1 tonight for blood brothers.  I am sure it wont be nearly as loud as Manson or Isis, so it wont be a good comparison.  I also have the preamp built into the spsb-1, and I dont think it is wise to use that with the cmc-8s EVER.  I know when running CSB > SPSB-1 (29 db preamp) > JB3, i get nasty distortion on high end shit, even if the overall sound is not that loud.  Oh well, what can you fucking do?  I think I just need a better setup at some point, better mics with an ad-20 in there or something.  PG has a killer setup somehow, and I want to know how he gets his to work correctly all the time.

[leegeddy]

So be warned, it appears that both CMC-4s and CMC-8s will overload in high SPL situations.

karl;

...not if you run them with phantom power.  i've ran my at853 in various situations and in really hi spl settings and never experienced mic distortion.

the battery box is the culprit, NOT the mics.

marc

[kfrinkle]

i would have to mod my CMC-8s, and then get phantom power capsule thingies and I am not gonna do that anytime soon.  Eventually I might buy some other CMCs from sound professionals with the 48v phantom power option.  but being broke for awhile, it isnt gonna happen any time soon.  maybe before the next tool tour.

[Karl]

A bunch of thoughts, hopefully to shed light on this discussion...

I have heard people say that the 4's sound better than the 8's, though only slightly (tonal quality). So there is a trade-off between size, and price/sound quality.

The distortion problems will be very similar between the two mics.  I think the only reason that others didn't have distortion, was because either they were pretty far away from the stacks, or the volume of the concert just wasn't as loud (possibly due to venue acoustics).

A preamp won't help whatsoever with distortion problems.

leegeddy is right on about phantom power--that's the best way to power these mics.  They are great mics when run on phantom power.

Another thought--about a year ago I was messing around with battery box power--and I boosted my battery box up to 18v.  I sat second row and recorded Dream Theater (with the CMC-4's, aka AT853)(loud, loud concert) and I had virtually no distortion problems.  18v battery box power is something I would like to see more people experiment with--it looks promising.  I don't think it will still be the same as phantom power, but for those who still want to be super-stealth and want to avoid distortion with this setup, I think it's prob a good route to try.

[kfrinkle]

Karl,

  I must say, from one Karl to another Karl, nice to hear this.  I actually have a bit of an idea on the whole issue now as well.  I was in a fairly high SPL situation the other night taping The Blood Brothers.  I was running CSB > SPSB-3 > JB3 and CMC-8 > SPSB-1 > JB3.  If you notice, the SPSB-3 takes those little fucking 9v batteries, and the SPSB-1 takes the standard box 9v.  I think they way they have the SPSB-3 and SPSB-1 wired (perhaps in my case only, but i doubt it), the SPSB-1 puts out more juice.m  When i stealth, i always use the SPSB-3, but I am thinking about trying to stealth the SPSB-1 instead at some of the big, loud as fuck metal shows, and see if it makes a difference.  So where do you get these 18v battery boxes?  A friend of mine tried using 12v batteries in the 9v spsb-3, and it added a ton of bass distortion, no matter how high his roll-off was.
  Ok, I am done rambling...

A bunch of thoughts, hopefully to shed light on this discussion...

I have heard people say that the 4's sound better than the 8's, though only slightly (tonal quality). So there is a trade-off between size, and price/sound quality.

The distortion problems will be very similar between the two mics.  I think the only reason that others didn't have distortion, was because either they were pretty far away from the stacks, or the volume of the concert just wasn't as loud (possibly due to venue acoustics).

A preamp won't help whatsoever with distortion problems.

leegeddy is right on about phantom power--that's the best way to power these mics.  They are great mics when run on phantom power.

Another thought--about a year ago I was messing around with battery box power--and I boosted my battery box up to 18v.  I sat second row and recorded Dream Theater (with the CMC-4's, aka AT853)(loud, loud concert) and I had virtually no distortion problems.  18v battery box power is something I would like to see more people experiment with--it looks promising.  I don't think it will still be the same as phantom power, but for those who still want to be super-stealth and want to avoid distortion with this setup, I think it's prob a good route to try.

[Karl]

+T for the good name!

In short, I made my own 18v box by simply hooking two 9v in series.  In more detail, I made my own battery box which runs on a regular 9v battery (I think it's very similar to the SPSB-1).  Then, by using those 9v battery terminals that you can find at rat shack, I connected the two 9v's together and connected them to the batt box.  I then used packing tape to physically (not electrically) hold the two 9v's together.  Now, two 9v's won't fit inside my batt box, so I just used more packing tape to hold the batt's against the box.  I tested both the 9v and the 18v batt box with my car stereo, which puts out decent bass SPL.  It was clear that the 18v worked better.

Now, I don't know if I would recommend 18v for just any mic, but I know it works well for the AT853.  But I would recommend experimentation!  Maybe your friend had a mic that's incompatible with anything above 9v.  I do have some old generic mic that came with my Sony WM-D3, and it didn't like 18v (the noise floor shot up through the roof).

[kfrinkle]

+T for the name as well  

Also, can you post a pic of this 18v adaption you have done? I am electrically challeneged, really.  I know that aint good for a taper, but its the way I am.  I have the CMC-8s, and  people have been modding the CMC-8s for 48v phantom power, . So 18v shouldnt be a problem.

[OOK]

Here is my 2 cents.  I have owned the cmc4's for years.  When I first purchased them I had a problem in high spl situations.  It is not the mic....its the battery box.  I had one of the original boxes , the kind you had to open up and adjust the roll off and volume sliders..............I found that no matter what I did the mics distorted...I talked to SP about the problem and what they did to fix it was they created a battery box with sperate mic inputs.  This meant that the mics went from a single trs mini stereo plug to each plug having its own trs mini plug.  This gave an extra 5 to 10 db of spl to the mics.  It lowed the impeadance from high to low.  The mics could now handle spls of 130 or great without a problem........ it made a huge difference......I ran The WHO from the 11th row in hershey infront of 12' high JBL subs and the show came out great.....no distortion.............Had I used the older Battery box...It would have sounded like crap......I don't know if they still do the mod...or if they still make that practicular battery box.....But I won't part with mine.....The Battery box from what I remember cost 200$ and I sent my mics back to be modded and that cost just a few dollars.....Like I said, I don't know if they still do it.........................What I recently found out is they now have the Phantom power adaptors to give the mic its full potential.........I am thinking about getting it to try the  mics with my minime........  Later...JK

[Weazel]

there are also those tiny 12v battery's im planning to make a batterybox from those.

[Karl]

+T for the name as well  

Also, can you post a pic of this 18v adaption you have done? I am electrically challeneged, really.  I know that aint good for a taper, but its the way I am.  I have the CMC-8s, and  people have been modding the CMC-8s for 48v phantom power, . So 18v shouldnt be a problem.

Actually, that's where battery power and phantom power differ.  Battery power delivers a voltage to only one side of the mic capsule; the other is at ground.  In phantom power, an equal voltage is delivered to both sides.  So, if we applied 48v through battery-style powering (and not phantom) it might damage the mics.

I would post some pics, but I have no digital camera, and not even a scanner.  A little challenging there, sorry!

JK, that sounds like it would work also, having a dual 9v batt box!

[leegeddy]

In phantom power, an equal voltage is delivered to both sides.  So, if we applied 48v through battery-style powering (and not phantom) it might damage the mics.

this is untrue and wrong. phantom power does not apply 48v to both sides of the capsule.

marc

[Karl]

In phantom power, an equal voltage is delivered to both sides.  So, if we applied 48v through battery-style powering (and not phantom) it might damage the mics.

this is untrue and wrong. phantom power does not apply 48v to both sides of the capsule.

marc

What does happen then? 

[kfrinkle]

Makes me want to find a 48 volt battery in the shape of a 9volt and slap that bitch into my battery box.  I am really really interested in this modded battery box that SP did for you though.  My only problem, is that if you spend 10 bucks at SP, you end up spending another 100 to make it all work fucking right.  they have always been nice to me, but I am broke and cant afford the cost of such a modifiication right now. (and i really wont plug in a 48v battery into my battery box, i love my mics too much, perhaps a 12 volt...)

[OOK]

Ok maybe I should have stated it a little differently....The mics were not recieving enough juice from the original battery box....I don't believe the box is passive.  It supplies power via a 9volt batt. to the mics.  What changed when going with the newer box was the mic input went from a single TRS stereo input to dual TRS inputs.  It changed the mics from high impedance to low impedance.  The box is still powered by a 9volt batt.    Its  not passive.  what causes the mics to distort is they are not recieving enough voltage to realize their potential.  Most portable decks with mic inputs supply about 1.5 volt of plug in  power.  I forget what voltage my battery box suplies but I know its more than 1.5vlts.  If I remember correctly I think its around 9vlt acoording to the guys at SP....Don't quote me through its been about 2 years since I talked to them...so yes your right it is the mics.......their just not getting enough juice......if your getting distortion......

[Karl]

Another thought--about a year ago I was messing around with battery box power--and I boosted my battery box up to 18v.  I sat second row and recorded Dream Theater (with the CMC-4's, aka AT853)(loud, loud concert) and I had virtually no distortion problems.  18v battery box power is something I would like to see more people experiment with--it looks promising.  I don't think it will still be the same as phantom power, but for those who still want to be super-stealth and want to avoid distortion with this setup, I think it's prob a good route to try.

You have access to both 9 and 18 Volts bboxes, all else being equal? Then you should make a pair of high SPL recordings using your stereo to demonstrate the difference. I would have expected the benefits to be minor at best and there are numerous disadvantages to going up in voltage. Increased selfnoise being one of them.

Jon

I saved the samples of my testing, but they are at home (I'm at work right now).  Can I attach mp3's to my post?  That's what I'll do if I can. 

The self-noise was a tad higher, but since it's an application for high spl's anyway, that's a non-issue.

[Karl]

Check out these two attacments...

These are SPL tests that I did in my car.  Playback is from an Alpine cd deck, into a PPI 5440 amp, all JL Audio speakers, the sub is a 12" in a bandpass box.  As you'll hear, the difference is more than obvious.  Also, I left two seconds of silence at the beginning of each track so that you can hear the noise floor difference (like I said, very minimal).  The car was turned off, windows rolled up.  Awhile back I measured my car stereo's output at 130+ dB.

Just for records sake, the test was done with AT853 (omni caps) into homemade batt box (18v vs 9v being the variable), into JB3 (no gain adjustments).  Enjoy!

[kfrinkle]

Damn homey, there is a HUGE difference there.  I want one of those.... i wish i had the cash, it would solve alot of my problems...

[Steelcorner27]

Yes you are right 18v makes them performance like night and day...(now for a shamless plug) Infact I have just the thing for you.

http://taperssection.com/index.php?topic=36228.0

Brad

[Brian Skalinder]

Check out these two attacments...

The 18v source is significantly louder than the 9v, which usually translates into "better sounding".  I know, I know...setting precisely the same levels for comps is NOT easy, I've done my share!  Anyway...after adjusting the amplitude and normalizing so they're both roughly the same loudness, I didn't hear much of a difference.  Granted they're MP3s - maybe the WAVs sound significantly different.

Edit to add:  upon further listening, the 18v source appears to have more pronounced and cleaner highs, tighter bass, better detail.  But...dunno if that's from the 18v power or the higher levels at the time of recording.  Hmmm...curious...thanks for the samples!

[Karl]

Check out these two attacments...

The 18v source is significantly louder than the 9v, which usually translates into "better sounding".  I know, I know...setting precisely the same levels for comps is NOT easy, I've done my share!  Anyway...after adjusting the amplitude and normalizing so they're both roughly the same loudness, I didn't hear much of a difference.  Granted they're MP3s - maybe the WAVs sound significantly different.

Edit to add:  upon further listening, the 18v source appears to have more pronounced and cleaner highs, tighter bass, better detail.  But...dunno if that's from the 18v power or the higher levels at the time of recording.  Hmmm...curious...thanks for the samples!

Keep in mind that the recording was an exact A/B comparison (with 9v vs 18v being the ONLY variable)--so the higher levels are a result of 18v!  There is approximately a 3 db difference between the two clips.

Yes, listen to the higher freqencies (cymbals esp).  The bass frequencies are what actually causes the distortion, but you can recognize the effect by listening to what the distortion does to the higher frequencies.

btw, I use LAME mp3 encoding--one of the cleanest mp3 encoders out there.

[kuba]

The CMC-8s overload in high SPL situations as well, FYI.  I was running CMC-8's > SP-SPSB-1 > JB3 for both Manson and Isis recently, and the Manson show had awful bass distortion, even though i had bass rolloff at 195 for that gig.  The Isis show has just a tad bit of high SPL distortion here and there.  Levels on JB3 never came close to overloading.  So be warned, it appears that both CMC-4s and CMC-8s will overload in high SPL situations.

My opinion on your distortion issues:

SP-SPSB-1 roll-off isn't worth damn used with JB3 because the condenser values are calculated against another input impedance (10KOhms, but JB3 has ~~37KOhms(?)). So that it wasn't rolled-off at 195dB, but much lower frequency. Correct me if I'm wrong.