Coleman Audio Monitoring — is it supposed to be this quiet?

[alexdingley]

I'm not sure how to talk about monitoring levels intelligently for this troubleshoot, but essentially...
1. I've always thought my coleman audio M3PH MKII ran a little "modest" in volume
2. I have always been run with the control-room knob wide open and my Focal Twin 6Be mains w/ sub have never been at "blow your head off" volume levels.
3. The headphones offer the same "modest" output. — I can put my phones level knob (on the coleman) all the way up, and the Sennheiser HD600 will not rip my head off (even playing full-bore mastered music at line level from the computer directly into the Coleman's inputs)

I have output LED meters on the audio i/o, so I know I'm sending full-level signal out of the device. (and this observation is the same with my metric halo interfaces as it was when I used an Antelope audio i/o. So I don't think it's some 'dim' setting or variable control on the interface.

Does anyone else on here use one of these, and are they just quiet?

I didn't really have much in the way of comparison until recently... I just took the Sennheiser HD600 headphones and jacked them into the Headphone out of the Metric Halo (which is monitoring the same feed that the coleman is) and the volume of the Metric Halo headphone out (with any boost) is like 3X louder than the coleman with the HP volume wide open.

I almost feel like the coleman is paternalistically set quiet so that I can't monitor louder than like 85db in the control room. Because seriously, I can't get much louder than that with the Focals... and they SHOULD be able to blow me out of my shoes.

[digitaldrummer]

so when you say line level from the computer - you mean from an interface, right? I'm assuming the outputs on that interface are set to +4? I don't think the Coleman has such input settings but it does have a big attenuator on it - so it is meant to bring the signal down, except that if it is wide open then that should be the same level as if you bypassed it completely and went straight out of the interface into your monitors. So if you are troubleshooting, that's the first thing I'd do - connect the monitors directly to the line outputs of the interface (the same ones that would normally go to the Coleman) so that you are bypassing it. (headphone amps are a different beast so I wouldn't use that as the comparison) Of course you may want something to control the levels of the line out so that you don't blow your socks off just in case it is that much louder. in other words, bring the line outputs that are going to the monitors down to zero and push them up slowly.

[alexdingley]

Yep... so I did that very test today.

I'm pushing 4+ Line level out of the Metric Halo interface's outs 1-2 (with them set as a pure +4 line send)
Playing Apple Music with the software fader turned up all the way — interface outputs are just kissing the red, depending on the program material.

bypassing the Coleman, I was surprised at how NOT loud the Focals are. There's no overall trim on the backs... just a hi-freq and low-freq adjust. I bring everything through the focal sub first and that doesn't have any sort of attenuator either (just double-checked the manual and re-looked at the back).

Using an RTA app that has typically come within 0.5db of the expensive one we use to check our stadium sound system... I'm getting a maximum of 81db at mix position with a 1KHz sine wave played at 0db in my DAW — coming out (in the red) from my Metric Halo line outs +4 / coleman attenuator is wide open.

What's interesting is, with a little configuration in the software control panel, the Metric halo can have its front-panel data-encoder functioning as a master volume too. It has currently no effect on the line-out level that I'm feeding, but I just changed the config so that it would... and it can attenuate down to silence, but it can also go up past 0db for what it calls about another 20db of boost to the line signal. — playing Apple Music through that out (with the Metric Halo acting in "monitor controller" mode) I'm able to achieve "rip your face off" levels from the Focals. And they sound good & clean all the way up to levels beyond what I'd EVER want to listen or monitor at. So... I'm not 100% sure what to make of all that. My speakers seem to have a pretty low input sensitivity (everything is set +4 — I checked the focals and they have a -10 vs. +4 switch, and both speakers are set +4) but can be as loud as a mid-sized PA system if you give them enough juice. But my mixing rig (through the Coleman anyway) doesn't really go beyond a very modest level.

While I normally try to keep my volume to somewhere between 80db-85db when mixing... I have to say, part of me feels like I'm absolutely missing something here... my Hafler TRM-8's were face-meltingly loud if you fed in +4 line music / My old Event 20/20 monitors were pretty damn loud too.

[digitaldrummer]

seems like you proved the Coleman is doing a lot of attenuation - I'd be giving them a call to ask why.

[Scodiddly]

Balanced/unbalanced connections between devices? That's an easy way to lose a few dB if you're not paying attention.

[alexdingley]

seems like you proved the Coleman is doing a lot of attenuation - I'd be giving them a call to ask why.

Oops, I think my post below was a little unclear. In my “bypass” testing of the system I actually proved to myself that the Coleman is not providing additional/unwanted attenuation. In the paragraph quoted below, I should’ve made that more clear. Coming directly out of the metric halo, I got the same 81db reading.

Yep... so I did that very test today.

bypassing the Coleman, I was surprised at how NOT loud the Focals are. There's no overall trim on the backs... just a hi-freq and low-freq adjust. I bring everything through the focal sub first and that doesn't have any sort of attenuator either (just double-checked the manual and re-looked at the back).

I now feel pretty strongly that it’s truly about the focal monitoring system… And that perhaps it just has a deliberately low sensitivity on the input. Thankfully the monitor controlling options of the metric halo interface make it so that I can overcome that with the additional boost that the monitor control circuitry allows.

I certainly don’t plan to monitor loudly, but it will be nice to have that extra oomph in those moments when I need to rock a little harder.

[Nick Sevilla]

What is the input sensitivity switch setting on your Focal monitors?

[alexdingley]

What is the input sensitivity switch setting on your Focal monitors?

It's set at +4 (it only offers -10 or +4)

And here's where I now come back to the conversation feeling kinda dumb.

So... I just took my Q-box and hooked it up to the ins of the coleman monitor controller / I played the Q-box tone at +4 through an XLR into the Coleman, and with the Coleman monitor volume wide-open I get a little over 100db at 1 Meter. Then I played the same 440hz tone out of the signal gen plug-in in Logic → out through my Metric Halo → into the coleman. And I had to give it (maybe you guessed it) +18DB of gain using the Metric Halo monitor-controller mode to equal what the Q-box is putting out.

So I gather that everything is fine, and none of my gear is behaving poorly or set up in a strange way, and it's just a matter of me failing to understand this whole "interface output calibration to -18dbfs" thing.

When I first started working with decent interfaces, in the early 2000's, I remember reading a ton of web articles and paper equipment manuals that talked about Reference levels. I now think it's 100% safe to say... that I am not fully grasping the why & the how these are set this way.

And now for the real question I should have been asking this whole time:

So... a 1KHz tone played out at 0db from the metric halo is actually playing back at -18db down from full-scale digital-zero. Why is that beneficial to my audio system? I think I understand that the digital inputs are calibrated so that 0 is really -18dbfs so that there's 18db of headroom for peaks that go over zero, so that they don't clip. — is the output set to match, just so that signal going in/out would pass through with no level-change?

Also, apologies in advance for forgetting whatever I learn in this thread and re-posting a similar question in like 7yrs.

[The Scum]

The interface is a ULN-8? Maybe the manual answers it:

They default to Monitor level,
which is optimized for connecting to self powered monitors or amplifiers. If you are connecting to another
device like a mixing console you can change this to Line.

Or more succinctly

Nominal FS output (Balanced) Output Jumper Off -19.0 dBu

You might need to read up on those jumpers.

[Scodiddly]

So... a 1KHz tone played out at 0db from the metric halo is actually playing back at -18db down from full-scale digital-zero. Why is that beneficial to my audio system? I think I understand that the digital inputs are calibrated so that 0 is really -18dbfs so that there's 18db of headroom for peaks that go over zero, so that they don't clip. — is the output set to match, just so that signal going in/out would pass through with no level-change?

Having that 18dB or so above "zero" is just kind of a convention by now. If you were working in the Yamaha world it would be 0dbFS and the meters would be calibrated for around -18dB when you start hitting yellow on the meters.

In other words, it's just a continuation of the grand tradition of level matching not making a whole lot of sense*. And of people having to grapple with the concept of gain structure in every situation.

*Speaking of Yamaha, at one point their flagship live console (PM3000, I think) had -10dB levels on the channel inserts. At the same time, their flagship digital effects device (some model in the SPX90/900/990/1000/2000) had switchable in/out levels - your choice of +4dB or -20dB.

[Nick Sevilla]

And now for the real question I should have been asking this whole time:

So... a 1KHz tone played out at 0db from the metric halo is actually playing back at -18db down from full-scale digital-zero. Why is that beneficial to my audio system? I think I understand that the digital inputs are calibrated so that 0 is really -18dbfs so that there's 18db of headroom for peaks that go over zero, so that they don't clip. — is the output set to match, just so that signal going in/out would pass through with no level-change?

Also, apologies in advance for forgetting whatever I learn in this thread and re-posting a similar question in like 7yrs.

The reason for this is because many consoles (converter people always assumed you'd connect a console for monitoring, like in a pro studio) Have usually a Master Buss level that is +N dB above the nominal ZERO of any given individual channel.

So that you can add a lot of channels together without having to turn them down too much. Usually an analog console has a fader "sweet spot" of +/- 10 dB around the ZERO level, or unity, for a channel.

Many consoles used either +16 or +18 dB as the HEADROOM for that Master Buss, and their individual channels as well. This headroom is above their Unity gain (where the fader sits at ZERO). Even if the fader markings say there is only +10 dB, it really will have more. It's sort of a safety feature.

So, converter manufacturers started referencing this level for their devices. This avoids overloading both an individual channels line input, and allows you to continue the traditional console workflow without having to recalibrate your console. In some instances, you cannot easily change the levels of the MASTER Buss (Neve, SSL, API and other do have this, as their master buss amplifiers have calibration trim pots.)

In your case, IF the converter already outputs a "zero" level on your DAW fader = -18dBFS at the physical output, all you have to do is set that on your console to be ZERO on the meters. And be happy. Unless your console is +16 or some other reference level, then you would add / subtract the level at the meter (but do not change the fader from the unity gain / zero point.)

Reference for dBu / Volts:

https://jeffvautin.com/2009/06/4-dbu-10-dbv/

[alexdingley]

The interface is a ULN-8? Maybe the manual answers it:

Ahhhhh.... and so it turns out I never downloaded the "ULN-8 Quick start guide" where that section exists. The control-panel software "MIO Console 3D" has a full user manual with tons of hardware specific info... so I took that as the "complete manual", but I didn't see anything in my quick perusal of that manual nor when I look for the key words in the .pdf search.

But I did just have a quick chat w/ John at Metric Halo and it was ABSOLUTELY what 'The Scum' suggested. Changing the "monitor level" preset back to a "+4" setting (in a panel that I would have never looked at for something like this) was exactly what I needed.

I'm even able to put in a gentler level-offset so that I can have it set that my coleman passive monitor controller (when wide open) is FULLY ROCKIN'.... but just shy of damaging speakers. Glad I finally spoke up, and thanks ALL for the great insights. especially that bit about the why/how things are configured. I am successfully back to using my Coleman as the main mon controller, but if I ever move into surround/atmos, monitoring... I now see how the Metric Halo monitor knob can be configured to be a fully-tailored Surround controller with the outputs handling offsets in level / delay / EQ curve. Pretty damn powerful.