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Barefoot mm27 gen 2 info needed Dynamics Processors (HW)
Old 19th March 2017
  #1
Gear Head
 

Barefoot mm27 gen 2 info needed

To all the barefoot owners out there, I have a question for you guys. more specifically related to the limiting/maximizing/mastering side of things.

Im currently about 5 months in with my mm27 Gen 2 purchase and i'm loving them. the translation is amazing and I really hear small imperfections and changes that I wouldn't have been able to hear with a lot of the other monitoring systems I've used. Even though my room is a little smaller then most they seem to fit perfectly. I even demo'd the mm35's before hand for about a week and ended up going with the 27's.

My main issue here is the limiter light that flashes when you get to a certain point. My output chain goes from Mac tower to an SSL nucleus (full gain) to an SPL 2381 for monitor control and talkback. SSL Nucleus is internally calibrated to my knowledge via the Soundcard, along with the SPL being fully discrete.

Monitor settings for output at 0, sub at -2

When playing back mastered records from CD or even iTunes, the limiter light kicks on at 75/100 volume level of the spl. A level where some of my clients want to surpass when wanting to hear playback (usually pop, rnb or rap guys).

My question to you guys is, have you had to additionally calibrate these monitors, because due to my knowledge and reading of the manual provided there is nothing stating that.

The thing with this is, when I go to try to put a mcdsp ml4000 or l2 or some other type of limiter on a well mixed track with no resonance build up in the low mids or anything, I get the red light coming on before im even close to full use of the maximizer, and in talking to the point where there isn't even any gain reduction attenuation. Between this and playback of mastered music triggering the red light, im kind of confused on where to make the next change.

If this is a calibration issue I mean I get it, but being at 0 on the monitor output setting, should this type of thing be happening?

I contacted barefoot support btw and was told to monitor the sub settings and they suggested running the monitors at -2db on the sub setting because its possibly being over driven. I have checked numerous times, same outcome.
Old 19th March 2017
  #2
Lives for gear
 

The mm27 can get very, very loud so there seems to be some other problem. Get an SPL meter and measure how loud you can go before the speaker limiter kicks on sending one speaker RMS pink noise (not peak!) starting at -20dBFs and increasing slowly. Report back the SPL number (C weighted, slow reading) from your listening position with a meter and the dBFS that you were sending at the time (once again, RMS not peak; there's a pretty big level difference between the two.) I would put your sub back to 0 before this test.

You could have something in your chain sending a lot of subsonics that is just garbage to send to a speaker but is kicking the limiter on.

And how far is your listening distance from the speakers?
Old 20th March 2017
  #3
Gear Head
 

Quote:
Originally Posted by pentagon View Post
The mm27

hey pentagon, thanks for your response. regarding the noise test, should the gain on the ssl / spl monitor control unit be full gain as I ramp up the noise? I will be using the pro tools signal generator plugin for the test.

if this is the case, the reading on the spl showed the light just starting to come on roughly right at 100-100.8.

I was sending roughly -20.8db of rms pink noise at the time according to the plugin.

sub at 0

meme setting on flat of course

by the way, I am using an spl iPhone app, not sure if that will suffice. it has the option to use c weighted though so hopefully it will be ok.

my listening position is around maybe 3.5-4 ft from the speakers, slightly elevated with tweeters at ear height.
Old 20th March 2017
  #4
Gear Head
 

pic of the settings that triggered the limiter.
Attached Thumbnails
Barefoot mm27 gen 2 info needed-img_0370.jpg  
Old 20th March 2017
  #5
Lives for gear
 

100dB SPL - You're listening REALLY LOUD and probably giving yourself hearing loss. Don't do that!

You can only listen at those levels for about 15 minutes a day before you damage your ears.
Permissible Exposure Time for Noise SPL sound pressure level and duration Guidelines How long can a person endure a certain noise level before hearing damage occurs health sound level noise hearing ears impairment tinnitus damage - sengpielaudio Seng

You may also want to read up on the Temporary Threshold Shift and Fletcher Munson curves etc. It will help you get better mixes too.
http://www.mixonline.com/news/profil...n-noise/377512
Temporary threshold shift – causes & treatments - hear-it.org
https://en.wikipedia.org/wiki/Fletcher–Munson_curves


Most professionals work for sustained periods at no louder than 85dB SPL C weighted.
http://www.soundonsound.com/techniques/monitor-wizard
Old 20th March 2017
  #6
Gear Head
 

Quote:
Originally Posted by explorer View Post
You're
im very familiar with this information, but this has nothing to do with what I am here asking. thanks for the contribution
Old 20th March 2017
  #7
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Quote:
Originally Posted by nephew312 View Post
im very familiar with this information, but this has nothing to do with what I am here asking. thanks for the contribution
You've just measured that the red light on the Barefoot's comes on when they are outputting over 100dB SPL at your listening distance. That's about what I'd expect from speakers of this design.

If that's not loud enough then get a PA system (and wear ear protection if you don't want to go deaf).

Last edited by explorer; 20th March 2017 at 08:26 PM..
Old 20th March 2017
  #8
Lives for gear
 

Thanks for the picture. First off, no gain staging sounds good at 100%. Set the pink noise generator at -20 dBFs (exactly, RMS) and reduce your SPL volume knob until it reads 85dB (C weighted, slow.) Then mark where that is on your SPL controller so you can always put it back (with a piece of tape or anyway you want.) It should be around 2 o'clock/3 o'clock.

Now go back to ProTools and increase the level. See where it goes to and what in dBFs and dB(C) SPL meter readout you get.

Unfortunately, Barefoot won't list their dB @ 1m number (there's a BS response for that -- you can find the response in one of the threads here; and you are close to 1 meter away) but I know I can go to the Dolby standards on them which is 105 dB(C) (and that is at 2 meters which is about 6-1/2 feet) without any lights.

If you still get lights, drop an eq on the signal generator track and HPF with a steep slope (24dB/octave; 4th order) and starting at 20Hz or below, shift it upward to see when the lights go out.

BTW, wear some ear protection through this since you'll be sitting at these levels too long to do these tests; at worse some closed-back headphones.

With a small room (what are your l x w x h?), you may have a case of the room working against you and nulling out frequencies so no matter how much power you are throwing out the speakers, it has to overcome the room. I was once in a near cubic room and had to squeeze myself into a tiny corner of the space (speakers and myself) to get out of all the nulls. There was a +15dB(C) jump by just doing that.

Quote:
Originally Posted by nephew312 View Post
hey pentagon, thanks for your response. regarding the noise test, should the gain on the ssl / spl monitor control unit be full gain as I ramp up the noise? I will be using the pro tools signal generator plugin for the test.

if this is the case, the reading on the spl showed the light just starting to come on roughly right at 100-100.8.

I was sending roughly -20.8db of rms pink noise at the time according to the plugin.

sub at 0

meme setting on flat of course

by the way, I am using an spl iPhone app, not sure if that will suffice. it has the option to use c weighted though so hopefully it will be ok.

my listening position is around maybe 3.5-4 ft from the speakers, slightly elevated with tweeters at ear height.
Old 20th March 2017
  #9
Gear Head
 

Quote:
Originally Posted by pentagon View Post
Thanks for the picture.


the 85db point on the SPL controller is at 45/100 (11:30).

the pink noise was maxed out at 0 and there was no light. The readout on the spl meter was something roughly around 101 with the spl controller at the 85db mark.

room L-17ft, w-12ft, h,10ft. the back right corner of the room where the door is has a wall that is a 45 degree angle, so there are 5 walls in the room. I have high frequency treatment along with bass traps. There is also some diffusion on the back wall. Not the best room I must say, but it is the best I have to work with at this point in time.
Old 20th March 2017
  #10
Lives for gear
 

Quote:
Originally Posted by nephew312 View Post
the 85db point on the SPL controller is at 45/100 (11:30).

the pink noise was maxed out at 0 and there was no light. The readout on the spl meter was something roughly around 101 with the spl controller at the 85db mark.
Since you run through two gain-staging areas, turn down the Nucleus if you still have it all the way up and put it at 70% and then turn up the SPL to where it is 85dBC again. It's odd that you ended up at 101dB. You should have ended up at 105dBC (-20dBFs at 85 dbC and then adding +20dB should bring your readout to 105dBC -- if not, there's a problem in the gain staging still.)

It's good that you didn't have any lights. Since you got louder than before, it sounds like something in your monitoring chain was/is generating harmonic distortion (when you had everything cranked) and when that hit the speakers it created the overloads and the limiters to kick in. It also means your audio was worse off.

Now, if you can get to 105 dB(C) cleanly on one speaker, two speakers playing will be between 108 dB(C) (incoherent) and 111 dB(C) (coherent) which is pretty damn loud. And remember this is RMS values. Peak values off of the Pro Tools signal generator are around +6 to +8 higher due to crest factor of the pink noise. So you are listening to peaks that much higher.

If you want to see what level you can go to after the pink noise is at 0, slowly increase the SPL's knob. You should choose only one place to adjust monitoring levels and I'd go with the SPL over the Nucleus since it is at the end of the chain.

Quote:
Originally Posted by nephew312 View Post
room L-17ft, w-12ft, h,10ft. the back right corner of the room where the door is has a wall that is a 45 degree angle, so there are 5 walls in the room. I have high frequency treatment along with bass traps. There is also some diffusion on the back wall. Not the best room I must say, but it is the best I have to work with at this point in time.
Your room doesn't sound like a massive issue. Nothing that will create a massive loss of sound though I'm sure there are some low frequency dips.
Old 20th March 2017
  #11
Gear Head
 

Quote:
Originally Posted by pentagon View Post
Since you run through two gain-staging areas,

after turning the nucleus down to 70%, that brought the 85db level on the SPL controller to that 2 o'clock or so position you were originally talking about which is 65/100.


the light hardly started flickering at 101 on the spl meter when the pink noise was maxed at 0, spl controller at the 85 db mark.


turning the spl controller gain up to the 70-75/100 position after the pink noise was at 0 made the solid red light engage. this was about 103db on the spl meter.

spl controller cranked all the way with pink noise at -20 gives a spl meter reading of roughly 94.5
Old 20th March 2017
  #12
Lives for gear
 

Sounds like you have a max (stereo) of 104 dB(C). You should leave your SPL controller at the 85dB mark. You can start playing with a HPF to see as I mentioned above to see if all the clipping is coming from low energy.

If so, the answer would be additional subs if you want to go louder.

I wouldn't drop the sub -2 unless you know that is accurate for your room (measure the room.) Otherwise you are giving yourself a little headroom only in exchange for a less translatable sound.
Old 20th March 2017
  #13
Gear Head
 

Quote:
Originally Posted by pentagon View Post
Sounds like you have a max (stereo) of 104 dB(C). You should leave your SPL controller at the 85dB mark. You can start playing with a HPF to see as I mentioned above to see if all the clipping is coming from low energy.

If so, the answer would be additional subs if you want to go louder.

I wouldn't drop the sub -2 unless you know that is accurate for your room (measure the room.) Otherwise you are giving yourself a little headroom only in exchange for a less translatable sound.

will do, thanks for the help pentagon.

so keep the nucleus at 70%, spl controller at 85db just to be clear, and any adjustments should be at the spl, not the nucleus right?

no adjustments needed on the barefoot end? would I gain anything by a boost or cut on the overall monitor output on the speakers?
Old 20th March 2017
  #14
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Quote:
Originally Posted by nephew312 View Post
will do, thanks for the help pentagon.
so keep the nucleus at 70%, spl controller at 85db just to be clear, and any adjustments should be at the spl, not the nucleus right?
Yes.
Quote:
Originally Posted by nephew312 View Post
no adjustments needed on the barefoot end?
yes.
Quote:
Originally Posted by nephew312 View Post
would I gain anything by a boost or cut on the overall monitor output on the speakers?
Definitely not boost. And you might gain 2 dB if you cut the bass by 2 dB but that may hurt your speakers sounding right overall. Best to get a measurement mic (<$100), and SPL meter (<$35) and grab the REW program (Free) to measure the frequency response of the room.
But if you need to go louder for clients, get bypass-able subs and wire them into the chain. Turn them on when you need to show off and go loud and turn them off when mixing. There are a few subs made like that.
Old 20th March 2017
  #15
Gear Head
 

Thanks pentagon!
Old 21st March 2017
  #16
Lives for gear
 

I'd suggest looking up Bob katz's article on setting up your monitors using his weighted system. I have marks on my Dangerous Monitor ST noting the different loudness levels, its very helpful.

Quote:
A level where some of my clients want to surpass when wanting to hear playback (usually pop, rnb or rap guys).
As an mm27 owner, if you're limiter is kicking on consistently you're seriously damaging your hearing. When I do hiphop sessions, I have to wear plugs. clients will just put the monitor on stun no matter what. Lots of those guys are totally deaf. Its really sad to see people destroying their hearing because of ego and stupidity. Its not cool.
Old 21st March 2017
  #17
Gear Head
 

Quote:
Originally Posted by Myles83 View Post
I'd suggest looking up Bob katz's
i'm familiar with bob Katz, actually own his mastering book. good read for sure. I had an outlook on this situation by thinking since the nucleus was calibrated internally via the Soundcard, I would have the ability to plug up the monitors and not have to worry about any type of calibration... in hindsight, definitely an unreasonable assumption from my end. I even spoke with a rep at vintage king and they informed me this was the way to go and told me they have seen people run them in the red lol! (I would never do this btw) Barefoot told me to adjust the sub level, and so fourth. Just a lot of conflicting information.

The person that turned me on to Bob Katz a while back ran k-14. Is that what you use? I really liked the dangerous and almost purchased it tbh, but the integrated talkback mic was what made me steer towards the spl and eventually purchase because from time to time I do travel with my rig.

I completely agree and I never monitor or mix at that level. Clients (some, not all) ask to hear playback after changes are made at a high level of volume and after I switch the meme setting to hifi & hit the spacebar, I typically walk out and take my quick 3 minutes or so. I feel like its more of the new generation having this constant need of wanting every sound to be as loud and as present as possible and your right, most of these guys are deaf.

It was just a scenario where when you get past a certain point of volume and things that aren't supposed to be distorted start sounding that way, you start to question things.. especially with this type of investment at least with me I want everything to add up properly.
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