View Full Version : Auto Levels on Zoom H4n


Adam Gold
March 9th, 2010, 12:30 PM
I know there are a couple of existing threads that touch on this, but none that go into any detail, and many people have misconceptions over how this works on the H4n. And while most experts aren't fans of auto levels, I find they are required for the shows and concerts we do -- the actual dynamic range that sounds great in the theatre is just too wide for videos -- people shouldn't have to turn up the volume during quiet songs and then turn it down for loud ones.

Anyway, we use the Zoom H4n and have been pretty pleased with it in most respects, except for the way Auto Levels work. As many of you know, unlike most devices, the Zoom adjusts the volume down during loud passages but never adjusts it back up. It's a one way trip. So looking at the waveforms on the timeline shows each song stair-stepping down in volume while the audience cheering (particularly as they get louder and more enthusiastic as the show progresses) stays at about the same level, as the recorder is constantly adjusting downward every time it hears the audience go nuts. Literally, the Zoom might start out at a level of 89 at the beginning of the show but then be at 5 by the end.

From the manual:
...the unit automatically determines the recording levels using the signal present during recording standby. If the volume surpasses 6dB [actually -6 dB according to the diagram below the text] during recording, the input level is automatically adjusted...

By the end of the show I am boosting the levels in post by 40dB or more just to get audio, and as you might imagine the hiss at this point is horrible. I am using both the compressor and the limiter in the Zoom as well.

So my questions are:

--Has anyone else experienced this issue, and is there a workaround I'm missing?
--Do other small recorders in this league work the same way, or do they do Auto Levels the way my cams do, that is, lower for loud sounds but then boost quiet ones?
--Or should I just give in and set an arbitrary fixed level and hope the limiter and compressor will keep the audio from clipping or getting similarly destroyed?

Thanks for any input you audio gurus may have.

Jay Massengill
March 9th, 2010, 03:49 PM
When using my Zoom H4n to record a live show, I engage the onboard limiter, use manual levels, and place a stand-alone compressor between my mixer output and the Zoom.
I set the stand-alone compressor for mild to moderate ratio compression with a high threshold, a quick attack and a moderate speed release.
I'm also controlling the mixer manually for all input sources and output destinations.
I have found this setup to be very satisfactory. While it is certainly a more hands-on approach, without the stand-alone compressor it would be too difficult to get a great recording level manually in a wide-ranging show but that isn't just an H4n issue. I haven't tried the H4n on-board compressor so I can't comment. Historically I've been using the stand-alone compressor to avoid over-driving inputs on various recorders, before the onboard controls take effect too late.

David Dalton
July 13th, 2010, 04:27 AM
Adam

I had this problem recently while videoing a local drama event - an actor had to slam a car door and after that the dialogue practically vanished. Since your original post, have you found a workaround?

Guy Cochran
July 15th, 2010, 12:31 PM
When using my Zoom H4n to record a live show, I engage the onboard limiter, use manual levels, and place a stand-alone compressor between my mixer output and the Zoom.
I set the stand-alone compressor for mild to moderate ratio compression with a high threshold, a quick attack and a moderate speed release.
I'm also controlling the mixer manually for all input sources and output destinations.
I have found this setup to be very satisfactory. While it is certainly a more hands-on approach, without the stand-alone compressor it would be too difficult to get a great recording level manually in a wide-ranging show but that isn't just an H4n issue. I haven't tried the H4n on-board compressor so I can't comment. Historically I've been using the stand-alone compressor to avoid over-driving inputs on various recorders, before the onboard controls take effect too late.

Jay - which stand-alone compressor are you using?

Jay Massengill
July 16th, 2010, 08:24 AM
I have a number of different stand-alone hardware compressors that I've used with the Zoom H4 and H4n.

dbx 1066
dbx 266XL
Alesis NanoCompressor (often using two - see below)
Symetrix 528e (again often two - see below)

The two dbx models are pretty straight-forward in their operation and are commonly found compressors. They can each be set for either two-channel separate operation or have the controls linked for stereo. Mine are rack-mounted with other audio gear in somewhat portable cases.

The NanoCompressor, which I often use if I'm traveling light since I have to carry all my own gear by myself, can only be set for stereo operation.
So when I'm recording two very different signals to the Zoom, such as one track of ambient and one track of program audio, I'll use two NanoCompressors bundled together. Each signal goes into the left (mono) connector of a single NanoCompressor. Then two copies of the compressed signal are available at the outputs. I can send one to the Zoom and one to a camera for each of the two signals I'm processing separately.

I've always wanted to get an RNC or two as replacement for the NanoCompressors but it hasn't worked out yet.

The Symetrix units are rack-mounted in the studio and they are mono only. So if I'm recording two voices I have to use two units.

Adam Gold
July 16th, 2010, 10:18 AM
I find Jay's method works well, except I haven't found the need for a standalone compressor. Basically I've learned that the Auto levels on the Zoom are for setting the levels during the sound check only, not for during recording. Use auto to set the levels manually -- it'll tell you where it wants to be -- and then engage whatever limiter or compressor you like.

Pete Cofrancesco
July 24th, 2010, 03:25 PM
I recently got an H4N and thought the auto levels would allow me to record an unattended at different location from the camera, like next to the stage or back in the sound booth. I was hoping auto levels would provide protecting against if the feed from the board or the ambient levels got unexpectedly too high. But I had the same problem you did, some loud unexpected noise sends the levels down too far and for the rest of the performance its too low.

For dance recitals the budget doesn't allow for me to pay a sound guy to monitor and manually adjust the levels. And that's what you need and no matter what equipment you have it keeps coming back to that. I'm going back to my original setup a mixer in reach of the camera where I can easily monitor and change the levels while I'm filming. Of course that means if you want to place the mics far from the camera you need a wireless setup to send the signal since its usually not feasible running cable where audience will be moving.

Steve House
July 25th, 2010, 06:50 AM
As you're discovering, there are a whole library of reasons the old-school methods of working evolved as they did - generations of professionals working to get the best results they could have painfully worked out what does and what doesn't work. The precipitous drop in the cost of hardware that makes it possible for small budget operators to get into the game has actually changed very little about what it takes to get the job done right.

Tom Bostick
January 28th, 2011, 03:17 PM
filming a musical tonight ,anyone have any more advice for not having a physical compressor?

Rick Reineke
January 28th, 2011, 07:53 PM
Anyone have any more advice for not having a physical compressor?
Worry about the compression in post. Just give yourself adequate headroom on location. Use 24 bit depth.

George Kalogeris
October 11th, 2013, 11:16 AM
any progress on auto-levels during rec ?
any newer fw ?

I am using manual Levels (about 70%) for a wedding.
Should I enable compression1 ,2 or 3 or limiter1 , 2 or 3 ??