View Full Version : Do I need a PPM meter?


James Collinson
February 9th, 2007, 06:33 PM
Hi Folks,

I am setting up a studio to start producing and editing corporate videos for the web and DVD, along with some music videos and short films. I am on a budget, but have already landed a few jobs for reasonable money (to me anyway!) here in the UK.

A friend who is an experienced producer mentioned that one of the more vital parts of my studio should be a PPM meter (suggesting that this should be put higher up my list of purchase priorities than the likes of a broadcast or color corrected monitor).

What do you guys think? and what should I look for in a PPM? Will it fit in my workflow?

Currently my workflow is something like this:

Canon XH-A1 with Rode shotgun >>>
intel iMac with lacie firewire drive>>>
Final Cut Studio >>>
Mackie CFX >>>
Genelec Nearfields

I'll soon be upgrading to MacPro with cinema displays, and choice of video and audio cards (might need help with that too!), and am also aware that other parts of my setup may need attention - such as storage etc. along with other needs that will have a draw on my budget, like lighting.

What the consensus?

Jim

Douglas Spotted Eagle
February 9th, 2007, 06:40 PM
I'd have to disagree. There are some great digital meters/software out there, and while a PPM is great (Have a look at the new Dorrough's), it's much less important than a color correction monitor or great monitor speakers, IMO.
If you're shooting HD, then color correction is even more important than for SD, again, IMO.

James Collinson
February 9th, 2007, 06:42 PM
Thanks for your prompt reply Douglas!

Are there plugins avaliable for final cut that would do an effective job?

Steve House
February 10th, 2007, 03:24 AM
Thanks for your prompt reply Douglas!

Are there plugins avaliable for final cut that would do an effective job?

Check out http://www.rawmaterialsoftware.com/ for a PPM metering plugin called 'PPMulator' that is very inexpensive. It has received a number of favourable comments on the 'Sound on Sound' magazine forums and is you can download a free evaluation copy to see if it works for you.

Allan Black
February 10th, 2007, 04:51 AM
Due respect to the above, I agree with Douglas, there are more important things to concern yourself with than a PPM, especially starting out.
You'll soon get used to your existing metering; set up a great reference audio station, speakers, headphones whatever works for you but spend money and a lot of time there.
Audio is soooo important, even to paying a pro to come in and set you up.

James Collinson
February 10th, 2007, 04:53 AM
Looks like a great plugin - really cheap too - but doesnt work with Final Cut at the moment which is a shame!

Jim

Steve House
February 10th, 2007, 05:14 AM
Looks like a great plugin - really cheap too - but doesnt work with Final Cut at the moment which is a shame!

Jim

Are you sure? I don't know anything about Final Cut but the publisher claims their plugin works with both PC and MAC OSx and works on the inputs of any NLE that supports VST or Audio Unit (AU) plugins. Doesn't FCP support AU?

James Collinson
February 10th, 2007, 05:16 AM
Yeah, there is a wee bit about it in the FAQ, says they are looking into it for the future.

Paul R Johnson
February 10th, 2007, 06:21 AM
In this digital age, the main requirement is preventing the levels getting to digital zero - so the meters in many applications now make that quite easy. We're not talking about mechanical meter balistics any longer, but proper, accurate levels, that can be indicated and even analysed. I'd suggest than old fashioned numeric ppm levels, presented via software using accurate digital level scaling as the source, are pretty pointless. Back in the old mechanical VU days, we all learned to interpret the wobbly meter readings, listen to the source material and make a considered judgement on how far to push. Thank goodness we don't have to guess any longer.

Brett Sherman
February 10th, 2007, 08:07 AM
In this digital age, the main requirement is preventing the levels getting to digital zero - so the meters in many applications now make that quite easy. We're not talking about mechanical meter balistics any longer, but proper, accurate levels, that can be indicated and even analysed. I'd suggest than old fashioned numeric ppm levels, presented via software using accurate digital level scaling as the source, are pretty pointless. Back in the old mechanical VU days, we all learned to interpret the wobbly meter readings, listen to the source material and make a considered judgement on how far to push. Thank goodness we don't have to guess any longer.

I'm sorry, but I have to disagree with your post. There is a difference between peak metering and loudness (or average) metering. Unlike CD audio which have no standard and eventually found it's way squashed at the 0dbFS ceiling, there is a standard for video audio levels. Average levels -18db(British) or -20db(US) and no peaks over -10dbFS.

When producing for Broadcast Television, because you're mixing ads in and going from program to program, it's important to have consistent levels. That's why PPM was created. That being said, there is nothing magical about the PPM number. It refers to a db level -18dbFS(British) or -20dbFS(U.S.) and an amount of averaging. If you keep your averages there, you're golden. then put a brickwall limiter on to make sure nothing peaks over -10dbFS. The problem with digital meters IS ballistics, they are too fast. Most digital meters built into non-linear edit systems are peak meters which are inappropriate for judging loudness levels. I know it's weird to talk about ballistics with digital meters, but analog VU ballistics, while inexact, had a useful function of averaging levels. You absolutely have to be able to view averaged levels, which is what the Dorough meters do. That's where a plug-in like PPMulator is helpful.

All that being said. For corporate and non-broadcast work. The level is not as important. Just try to keep the -20dbFS average level. You don't want to blow your audience away with a -10dbFS average level after they've just switched DVDs. Also, I don't want a client to play my DVD after one produced by someone pushed their levels to 0db and have the client ask why my DVD is so quiet. Let's make life easier for all of us and follow the standard.

Douglas Spotted Eagle
February 10th, 2007, 11:05 AM
PPM Metering is very important; as mentioned earlier, We have a multi-standard Dorrough in our shop, and it's part of the system (always metering). PPM is necessary for all forms of video output, IMO, and useful for marking a standard point for CD output as well. But to put an external PPM at the top of any 'new' purchase list is putting a cart before a horse, IMO. There are so many great software solutions.

http://www.filesland.com/download/meters.html has a few.

Paul R Johnson
February 10th, 2007, 12:27 PM
I don't have a problem at all with the final levels on the distribution media - but this is the final stage - I'm more concerned with levels in the pre and post stages when I still find I'm having to drop audio out of the digital domain, to get it through an analogue device for treatment, then back to digital again. My concern here is to maintain s/n and as a result I'm looking to keep the levels high and clean. I'm concerned with peaks here. Matching levels between different items of kit is hard enough. My final processing is usually some kind of compression, depending on the product, and although true ppm balistics are available to me, with even moderate compression, it's not too difficult keeping the needles hardly flickering. In fact - I spend a lot of time trying to expand dynamics on some material that is too compressed. My worry is just that using ppms before the 'final' stage tends to produce results that have been too compressed, as ppms do hide the middle ground, as a result of their averaging process.

James Collinson
February 11th, 2007, 11:30 AM
This is all really useful stuff guys, thanks for taking the time to give me some advice! It is a relief to hear that id perhaps don't have to budget in yet another expensive piece of kit just yet!

Jim

Vito DeFilippo
February 11th, 2007, 06:44 PM
I don't know if you can get these to run on an intel Mac, but here are some freeware ppm meters for PC.

http://www.darkwood.demon.co.uk/PC/meter.html