can you do a frequency sweep (20Hz - 20kHz) to see if it's a round some or all frequencies? are there any settings in the Fat Channel or other sound processing active?

Not sure about the RM's metering, but the console mixer's output meters use a different scale than the inputs. Maybe the same things is true with the RM?

To test if this is just about meter scales you can patch the output back into an input and then compare input meters.

Do remember that the main and mono trims at max add 6dB to those outputs. With a bit of fiddling, still using the input meters, you can trim that gain back to zero. Then you should have a fair input to output gain check.

Still a mystery, but here's some data for discussion:

Try this: plug in a mic to any single channel, turn off any fat channel settings. Play some music or anything, and let the mic pick it up. Set 0db gain on the channel fader and on main output fader.

The main (and mono) meters kick up 20db higher than the channel meter! I've checked this on two devices, and all channels - and it is regardless of the preamp level. GEQ is off. This is the same even with nothing connected to output and does not change with the main/mono output trim settings (we would expect the main meters to measure the internal master buss level so that makes sense).

I did as SwitchBack suggested and patched mono into an input, and you can see that the output trim does indeed adjust from -60 to +6 the output gets adjusted accordingly.

When I set the mono output trim to 0db (have to eyeball it) then set the channel preamp gain to 0db, the channel meter shows the same as the mic channel - that is what I'd expect - shows the gain staging is electronically correct - I can achieve a unity gain path of 0db.

This leads to the conclusion that the main/mono meters display 20db higher than the actual 0dB level?! (This is true on both Mac Universal Control AI and UI Surface for iOS, so is not an app issue, but maybe a calculation in the buss meters inside the mixer?)

Try this on your unit and tell me if Im crazy... I don't have a StudioLive to compare it to - I just have the RM16ai, but would be curious if this is different on the StudioLive systems.

Thanks guys, being an old console guy this is driving me a tiny bit crazy(er).

Hi,

It could be something to do with this, sub groups and main meters are measured on a different scale than channel meters

http://support.presonus.com/entries/222 ... bFS-vs-dbu

Wow, thanks shaneboaden,

Indeed this does look like it's done by design, as the tech note at that url tries to explain.

As an "old console guy" I only ever saw VU meters, which seems to match with the concept of dbu (the old 1mW into 600 ohms measure), regardless whether they were channel strip meters or buss meters. We were less worried about the occasional peak slipping though, since something along the path would take the edge off in a nice harmonic way...

Thanks for the response and the pointer, looks like I have a lot more reading to do about what metering in digital means. If you're like me, also looking for more about what gain staging is and how to think different for digital metering, read http://www.soundonsound.com/sos/sep13/a ... headed.htm

ok, so here's a question....

I could answer this myself through experiment, but both my SL32 and RM32 are packed for gigging.
The main outputs are rated to +24dbu (with output trim at max), which matches the published scale for the main output meters. But if I turn the trim down to give a max output of +18dbu, the entire mix will be quieter, so does the meter reflect this? or is it displaying the (+24dbu) signal being sent to the output and not the actual output?




Edit to fix inaccurate trim details.

So out of curiosity, I setup my rack and console last night to check the meters and discovered an "interesting" issue..

Equiment:
SL32 (+AVB)
RM32
MacBook pro

MacBook connected to SL with FireWire and RM with WiFi
SL and RM linked with AVB, direct cable connection.
All software and firmware at latest versions (as of yesterday)
All (used) faders set at 0db (unity)
Sub3 and Sub4 on SL linked as stereo pair Sub(3-4)
I initially had great difficulty getting the SL to recognise the RM over AVB, but that's for a different thread...

I fed iTunes from the Mac into SL channels 31-32 via FireWire. Mains and Sub(3-4) selected as output.
Using the channel input meter on the SL as reference, I adjusted the output of iTunes to give approx. -18db input. The output meters (mains and subs) all show 0dbu. This implies to me that the output metering (and the signal sent to the output amp) ranges up to +18dbu (+24dbu available at output by turning the trim to +6)

All great so far and exactly what I expected.

So.... Turn on UC Surface and take a look at the SL. The main output matches the LEDs on the console, 0dbu. but the channel input shows approx. -20db on the displayed scale. But the scale goes from -60 through 0 to +10? +18? It's clearly intended as a scale for the fader, not the input meter. Ok, I can live with that. I can judge where the meter is for a -18db input.

But here's the kicker.. switch to Subgroup view. The flex fader for the Sub(3-4) shows the same LOW level on the meter and NOT the 0dbu showing on the LEDs on the console or on the Main out.
This is wrong. Whatever the meters may or may not be displaying, they should always at least agree with each other...!!

Feeding the signal to an Aux(pair) gives the same result. The Aux(pair) output meter in UC Surface matches the level of the input meter when it should be showing 0dbu Output.

Can someone else please check this out to make sure I've not done something totally stupid.

Update, SL Remote AI displays sub output level correctly.

I had a veeeery long tread/discussion in the old forum about gain staging in the classic SL mixers. Bottom line was that imho gain staging in those mixers left room for improvement. I would be interested to hear if some of the observations and arguments from that thread hold true for the RMs too.

For those interested, here is the tread I'm referring to. A bit heated at times, but nicely on topic all the way

I will say that on the StudioLive 16.4.2AI, when I look at the "big meters" display in Capture, I see a different picture than I do on the console or in UC Surface. I've learned to trust Capture since I'm recording these gigs.

Hi guys

Anyone have an new info on this topic as to why the master gain is much higher then channel?

year 2017 uc surface 2.0 mines still seeing the same thing. . .