Reading VU Meters & I/O Level

[Kaleb TreacyParticipant]

Hello!

Just starting to familiarise myself with outboard gear so I apologise in advance if I sound a little novice. How do you go about reading/working with VU Meters, is it always about trying to hit 0vu on everything that passes through it? And also, on my compressor, I have an I/O Level at the back, "In" - 0 = +4db and "Out" - 0 = -10db. The manual states that "In" is professional mode and "Out" is consumer, so I have assumed I'd leave it In professional? Doing so, would that mean I'd try to hit a little less on the VU Meter? 0 on the output meter = +16dbu in "professional" and +6dbu in "consumer". What would you suggest running it in and how would you read the meters in that mode (i.e, aim for -16 on the output if in Professional)?

Thanks guys! I look forward to making sense of this thing,
Kaleb

[echoesParticipant]

I can't answer your question, but I'm interested in the answer!

Anyone?

[Kaleb TreacyParticipant]

So am I! It's totally tripping me out. Warren... ha ha

[Warren HuartKeymaster]

Hi Kaleb, I'm old school, I keep everything at +4 and I read everything around 0db on my VUs. I hope that helps? Have a marvellous time recording and mixing, many thanks Warren

[John GleasonParticipant]

Kaleb, just a little more background: when you set the switch on your unit to +4dBu (the 0 VU standard for pro equipment) or -10dBV (the 0 VU level for home stereo gear), the meters will show 0 VU to the appropriate standard (you don't have to make any adjustment yourself). I use the needle-type meters all the time to show me what is going on "outside the box," but you shouldn't rely on them too much since most of those meters average the signal and may not reflect peaks which may be distorted or clipped. The bar-type string-of-lights meters can show the peaks but I always feel I'm missing some information and tend to treat them like "idiot lights" on auto dashboards (just being me!). In the end, the meters in your DAW will show you the final result, and if you exceed the peaks on the fader meters the signal is clipped and the peaks are gone forever (easy to hear). Everyone has their own idea of where to set the signal level on their tracks, with 0 VU being the de-facto standard, some go a little lower (a lot depends on how you handled the compression to tame the peaks). Basically, don't clip your signals and leave some head-room at the top for mastering!

'Hope this helps.
John

[Kaleb TreacyParticipant]

Thank's John, that makes a lot of sense. So at the end of the day, I should just leave it what it's set on and just use the DAW to see what's going on?

[John GleasonParticipant]

Basically, use your DAW peaking meter to set the output level on your outboard gear rather than relying on the gear's needle meter (don't ignore it, just use it as a guide). For example: if you have a single piece of outboard gear as an insert, set the DAW output level to the insert at 0 VU, set the gear input level at 0 VU on its meter or just below the clipping light, and then adjust the gear output so the insert channel in and out meters in the DAW are at the same level. This should get you close.
You also need to watch the levels BETWEEN your outboard gear (if you are using, say, both a separate compressor and EQ), since the DAW meter can't tell if you clipped anything before it got into the DAW. If every piece of gear doesn't have an input meter or at least a clipping light (some don't), then you will need to listen to the to the signal coming into the DAW and adjust each piece of gear until you are comfortable that the levels are OK (up but not clipped). The more scientific approach is to insert a test signal (say a 1 kHz sine wave at 0 VU) into your channel line input and adjust everything down into the DAW (ins and outs) to read 0 VU. That will give you some confidence in your gear and a reference point that you can adjust from. (If your DAW doesn't have an audio test signal, you can download one from the internet.) Of course, all of this won't make anything sound better, but it can keep it from sounding worse!

I hope this makes sense.

John

[Kaleb TreacyParticipant]

Yeah that makes perfect sense! Thanks so much! A few quick questions if you don't mind though, I have always been treating the Output on the gear as "Make-Up Gain", is that not the way to use outboard gear (i.e I'm better off trimming)? Also did you accidentally say VU when setting it to 0 on my DAW meters? Because I've flicked my meters to VU on PT but to get it to hit 0VU, I had some serious clipping going on so I settled for -5ish VU. Could it be cause my original signal was too hot to begin with maybe?

[John GleasonParticipant]

Kaleb, you are right about "make-up gain" (unity), which also means that the input level has to be correct in order to have the correct output level. Pro-level 0 VU (+4dBu or +1.228V RMS), is a hot signal but should not clip in your gear or DAW.

(continued below)

• This reply was modified 7 years ago by John Gleason.
• This reply was modified 7 years ago by John Gleason.

[John GleasonParticipant]

You can check the input level to your gear by using a test tone in the DAW and set the DAW output going to the insert channel at 0 VU (can be any level but 0 VU will make it easier to calibrate the meters in your outboard gear). Then check the input level on your first piece of gear (if it doesn't have an input meter use any piece of gear that does). Then adjust the output of your A/D converter to match the DAW output meter level (meaning that the input to your insert gear is at the same level as the DAW output to the insert channel).

(continued below)

[John GleasonParticipant]

Then move down along your outboard gear matching each input and output to the same level. This puts your whole insert channel at unity. Then, check the DAW meter for the input returning from your gear and adjust the input level on the A/D converter so that the DAW insert input matches the same level as the DAW insert output (and all of your outboard gear you just matched). With everything now at unity, this should resolve the clipping.

Please let me know if this works.

John

[Kaleb TreacyParticipant]

This is very interesting. Righto, I'll go from the beginning. So, I'm only using inserts to one outboard piece at the moment (a compressor), to try and figure it out simply. I'm using a 10Khz sine wave inside of PT that I gained down to 0VU. To use an insert (correct me if I'm wrong), I'm setting that sine waves audio track insert as Insert 9 and returning it to another audio track with channel 9 as the input. When I chuck the insert on the sine wave, it jumps it up another 2.6dbs so I gained it down another -2.6. Now the send and return are both hitting 0VU equally, unreal! The input VU on the compressor is sitting at about -3.5 though, is that a problem?

Also, if 0VU is at -11.4 ish should I aim now to peak around there when I track? As I was aiming for -16 - -18 on my loudest sections.

Cheers John you champion!

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