Topic: Distortion with Scheops CMR rig!

[nicegrin]

I just recently recorded a pretty loud rock show in a small club using the following set up:

Scheops MK4 -> CMRS -> Tinybox (level set to LOW) -> Edirol R09 HR (line in, rec level set to 17/80)

For the louder songs my levels peaked at -6db on the edirol, still I have lots of distortion in the recording. The clipping seem to occur at about -6db with these settings as the songs that peak about -12 db sound fine and distortion free.

What causes this clipping? Am I overloading the preamp?

Also, any TS:er that use a similar setup and could comment the reclevels and suggest other settings?

Thanks
N

 



 

[Teen Age Riot]

17 on the R09HR is very low, so it looks like you were brickwalling the Edirol's line-in.

How much gain does the "low" setting on your Tinybox add?

[hi and lo]

eww.... I'm this close to buying a pair of cmrs so this is not good news 

I have never used an R-09 HR, but have plenty of experience with an nbox's +20db fixed gain overloading the line input of an R-09. I don't really know what 17/80 would indicate, but I used to hit 0dB at 1/30 on the R-09 which was not good.

A sound clip would help and my first suggestion is to use attenuation between the tinybox and recorder. The R-09 HR should handle a much hotter signal than the original R-09, but with my familiarity on the topic, I won't be surprised if the Edirol is the weak link. They're great recorders if you aren't feeding them a very hot signal.

If you've still got distortion using an attenuator, then the problem lies upstream in the signal path. Go from there I suppose.

[page]

My guess is the edirol overloaded since the peaks at -6 are bad but -12 isn't. It won't take a pro-level signal which is why some folks report distortion with the nbox.

You sure you had it on line and not mic in, or that the tinybox wasn't accidently set to something other than low? I've done fiddly stuff myself that messed up settings before.

[page]

I don't keep records of tinybox gain settings, so I don't know what your low setting is.  People have ordered anywhere from 0dB to 12dB for min gain.  Standard is 4dB on low.

CMRs drop 4dB from the capsule sensitivity vs. CMCs, so that's about -41dBV/Pa.  tinybox clips at +13dBV.  That's 54dB of headroom from 94dBSPL, less gain, less volume above that.  So at 134dBSPL and 10dB gain, you should still have 4dB headroom.  That's pretty loud . . . note that is a peak level though, not an average level.  There could have been a peak-to-average ratio of 20dB, so a really loud show can push peaks even higher than that.  In that case, you have to start worrying about overloading the mics too (mics tend to clip rather gradually though).

and doing some serious hearing damage. OSHA says anything over 120dbspl and damage starts to occur.

tinybox will clip suddenly, just as the Edirol's analog front-end will, and ultimately its ADC if the box can get itself to that point.  It's pretty odd to have an analog front end that cannot cleanly feed 0dBFS though, unless the digital level is attenuated post-conversion (which of course is useless for preventing overs).

the korg mr-1 was the same way, you could blast the poo out of the signal before it got to the box, and no matter how much you turned the levels down on the recorder, past a certain gain rating on the korg it would look ok, but sounded like ass cause you'd already brickwalled.

[darktrain]

I have never had any issues with my cmr's and sony M10, and i have recorded some pretty dam loud music(slayer, megadeth, anthrax, Deftones, Mastodon, etc....) and from small venues to midsize/larger venues

[F.O.Bean]

I'm HOPING my LB>R09 doesn't do that. Because I would run my LB at MIN gain, which is +4db, so that SHOULD NOT overload the R09, but I wont know til I get it in the field

[nicegrin]

Thanks for answer so far...

No one out there using the R09-HR with the Schoeps CMRs?

Since I also have a sony m10, what settings are you guys using with that for a loud show running the cmrs?

[darktrain]

Thanks for answer so far...

No one out there using the R09-HR with the Schoeps CMRs?

Since I also have a sony m10, what settings are you guys using with that for a loud show running the cmrs?

Really didnt matter what I have run th m10 at I have had it down to 2 and cranked to 10 for quieter rock running low and mid settings

[nicegrin]

Maybe a stupid thought but anyways...

Would throwing a 9v BB into the chain help the ER09-HR from brickwalling already at -6 db?
I´ve had similar experiences when running mini-plug mics straight into recorders so that´s why I asking...

Chain would then be  MK4->CMRS->Tinybox->9VBB->ER09HR...

Does it make any sense? Could it result in any negative effects?

/N

[page]

and doing some serious hearing damage. OSHA says anything over 120dbspl and damage starts to occur.

True, but consider a few things:  that is 120dB-A, which is average (RMS), not peak, and is A-weighted.  A-weighting pretty much chucks out bass frequencies, which are not really damaging to your ears, but are naturally the loudest part of the spectrum.  When you test a circuit with a sine wave, the peak-to-RMS is only 3dB, so that means for example tinybox cannot exceed +16dBV peak.  But if you are at a rock show that is 120dB-A, that could easily have bass peaks exceeding 135dBSPL.

true, I forgot about the A-weighting.

still f'ing loud.

I have never had any issues with my cmr's and sony M10, and i have recorded some pretty dam loud music(slayer, megadeth, anthrax, Deftones, Mastodon, etc....) and from small venues to midsize/larger venues

The M10 can also take a signal upwards of +24dbu IIRC.

Maybe a stupid thought but anyways...

Would throwing a 9v BB into the chain help the ER09-HR from brickwalling already at -6 db?
I´ve had similar experiences when running mini-plug mics straight into recorders so that´s why I asking...

Chain would then be  MK4->CMRS->Tinybox->9VBB->ER09HR...

Nope, if I'm correct in that it's the edirol that's causing it, then nothing short of an attenuator would work between the tinybox and recorder.

If you have an M10, I'd recommend using that instead for loud stuff.

[it-goes-to-eleven]

What is the saying?  Something about people who don't learn history are condemned to repeat it

The r09 and r09hr (and apparently mr1) will distort input (bass, in particular) when run below a certain gain setting.  On the r09, 8 is as low as I would go.  I don't know the equivalent for the r09hr, it should be in the FAQ, but I don't know if it is.   We should really have a FAQ for each of these recorders - I know there was one for the r09.  It sounds like you need an attenuator.

It was years ago when I found the value of 8 on the r09 via bench testing.  There were quite a few folks here who still insisted that the distortion did not exist, and was not a problem.   I think they've all stopped spouting that - to some people, saying something bad about gear is like calling their baby ugly - even if it is a hard fact.  I don't think anyone has bothered to do this testing with the m10.   Send it deep bass, right near 0dbfs, at each gain setting, and then examine the recording, looking for audible and visible distortion in the shape of the waveforms.

Fwiw, I have overloaded schoeps with cmc6's - both in practice, and in theory - when I worked the numbers after the show.  It does happen.  Two words:  Dinsosaur Jr.

Of course, I don't think anyone has tested the CMR's vs. the cmc6's in extremely loud situations.

[acidjack]

It would seem that you'd need your tinybox's minimum gain setting to be 0 and then run that line-in to the R-09HR with the -09HR set to around 40.  If THAT overloads I would be pretty surprised.   I wasn't running Schoeps but I stack-taped Mogwai at a club with a very good sound system and -09HR took that just fine.  Not sure how well my ears would have done absent the plugs I had jammed in there

I'm also curious about what situation caused overload of Schoeps CMC6 - I've run those in some pretty intense situations as well, including stack taping a huge PA, and A-OK. 

[hi and lo]

The r09 and r09hr (and apparently mr1) will distort input (bass, in particular) when run below a certain gain setting.

Very true about the R-09, but according to the bench tests performed by GuySonic, the maximum input voltage of the R-09 HR version is, supposedly, significantly higher being nearly equivalent to the M10.

I am skeptical after my troubles with the nbox/r09 combo (where the problem lies entirely on the R-09), but the numbers would lead me to the HR version is much better and shouldn't overload under most circumstances.

[Teen Age Riot]

It would seem that you'd need your tinybox's minimum gain setting to be 0 and then run that line-in to the R-09HR with the -09HR set to around 40.  If THAT overloads I would be pretty surprised.   I wasn't running Schoeps but I stack-taped Mogwai at a club with a very good sound system and -09HR took that just fine.  Not sure how well my ears would have done absent the plugs I had jammed in there

+1
We still don't know what the "low" setting on the OP's Tinybox is. If it means say +12db, then that's the answer right there.

FWIW I've never managed to brickwall the R09HR (or the R09) with the MBHO/MP2 combo, not even under extreme circumstances (stack taping, Dinosaur Jr etc). The MP2 adds 6db, while the sensitivity of the mics is 14 mV/Pa.