View Full Version : Zoom H4n and live show major issues
Thomas Moore June 29th, 2010, 07:44 PM OK, been doing reaserch and after much of that I decided to purchase a Zoom H4n for 2 live shows I was set to record. I've had great success taking soundboard feeds directly into my Panasonic HMC-150 but read so much about this recorder that I decided that it would do nothing but improve my audio for videos.
Well, that didn't work out well...
Settings on ths Zoom 4 channel, outdoor with a Rycote deadcat on the Zoom's internal mics, two live feeds from the sound board into the XLR inputs on the Zoom, -40db pad plugged directly into the Zoom from the cables coming from the board as I found that the Zoom only does mic not line and this was what my reaserch told me to do to limit the "hotness" of the board. Set good levels on both the internal and onboard mics, clipping was not an issue...
Zoom positioned on Mic stand about 20 feet directly in front of both groups about 4' feet up, internal mics set for 120 degrees stage outooor ampitheatre. No limiters or compressors set on the Zoom all default.
All through show listened to audio through Sony MDR 7506 headphones, sounded good, listening to the recorder in play back mode through same headphones sounds good.
Pull .wav files into any audio editing software, Vegas, Audacity etc, internal file is complete garbage, Microphone audio muffled, layer both no help....
Help!
Bill Davis June 29th, 2010, 08:59 PM Thomas,
It sounds to me like you've been studying how to operate the Zoom H4n when it might have been better to spend a chunk of that time studying how a sound reinforcement FOH (front of house) mixer (both the mixing board AND the human controlling it) operates.
No piece of equipment, no matter how accurate, or quiet, or high fidelity can do anything other than record the signal presented to it. That's a hard and fast rule and NOTHING can change it.
The biggest problem in taking a feed from any mixing console is that unless that console is dedicated specifically to directly feeding your recorder - ALL the choices that the technician makes in operating the console are designed for one thing and one thing ONLY. That's to make the best possible mix for the ears of the audience. Period. End of story.
Simply grabbing some form of two track mixdown from the board may or MAY NOT do a good job of feeding your recorder. Even if the levels are correct, even if the board feed is clean and not infected by anything from ground loops to low-cut filters or high-cut filters that were possibly needed to balance the output of the board with the amplifiers and speakers being used in the VENUE - that feed may have some characteristics that you simply DON'T WANT in the stereo recording you're making at your device. And there's NOTHING you can do about that. You're taking a mix that someone else is determining.
That mix might start as one thing - let's say a nice stereo mix where the drums and bass are well balanced with the vocals and keyboards. And at ANY point in the performance, the board operator may feel that this mix is WRONG for the listeners and boost something or cut something that now presents an IMPROPERLY balanced feed to your gizmo. And again, there's NOTHING you can do about it.
For most FOH mixers I've delt with, they have barely enough time and resources to get their main mix and the monitor mix that the band relies on to hear themselves correct. Then at the very last minute, some video guy like you or me shows up and wants them to suddenly patch in a stereo feed. Making sure that it's a pre-fade, rather than post fade, and that it somehow perfectly balances all the proper sub-groups such that while the FOH operator makes changes in the main mix, that precious STEREO signal that has NOTHING to do with the job the FOH operator is being paid to do remains perfect as well.
The real point of this is that if you want to take feeds from a FOH mixing console, you have a responsibility to learn how to assess what the feed consists of (Is it balanced or unbalanced, line or mic level, is it pre-fader or post fader, if subgroups are involved, how are they patched and what does that mean to the overall balance of instruments, frequencies and channel separation, what about effects and outboard processing - is the vocal track wet or dry? And if it has reverb or other outboard effects applied, is the level set for the audience appropriate to your recording or do you need a patch that presents only dry vocals to your tape so you can set the level of effects later? ) and what each of these aspects means in terms of how you need to cable, pad, set levels, and record at your device in order to maximize the quality of your recording.
Bottom line? Quality sound recording seldom gets the respect it deserves. And this is a good example of why. It's necessarily complex and often less than intuitive.
As to your particular results on your Zoom in practice, it sounds like somehow your recording levels were set wrong and the signals over-modulated - which in the digital domain also means they self-destruct. Sorry.
(But don't trust me - copy the stuff before you erase everything - there are a LOT of things than can make sound stuff sound bad. Maybe you'll discover what's wrong and be able to fix the files later. This is actually supported by the fact that you say you were able to get clean sound off the ZOOM playback. If that's possible then one would expect that you have good files somewhere! (hope springs eternal!)
Good luck.
Thomas Moore June 29th, 2010, 11:31 PM Thanks Bill and that is part of what I hoped the internal mics would cover as I have read the horror stories about sound guys feeding us bad audio - as you say through no fault of their own, neccesarily but because they are paid to make sure the house is happy. This is why I hoped that if this happened the internal mics would save me but alas even that is not the case...
I've heard "live" recording samples from the Zoom using only it's mics and was very impressed, I know what clipping/over modulation sounds like and this is not the issue on the front mics, or from the inputs it just sounds garbled/muffled heck my shotgun mics on my cameras sound better then what I got off the zoom's internals, which makes me think I did not set something I should have or something is really wrong with my recorder or both.
Files are saved in several places believe me :)
Thomas Moore June 30th, 2010, 01:02 AM and for a short example of what I'm talking about from the internal mics:
YouTube - zoom.mp4 (http://www.youtube.com/watch?v=JS4fvVneKnY)
Michael Liebergot June 30th, 2010, 08:39 AM Ok first and foremost, where is your recorder positioned?
Was it directly in front of the PA stack, up front to the side of the PA stack, or in the rear by the camera.
I ask because if your recorder was by the sound board a good distance away, then what you got sounds about normal for the onboard mics, as large venues for rock shows tend to sound boomy anyway.
The first rule of micing for good audio is placement, the second rule is placement. You get the hint. The close your mic is to your source the cleaner your audio will be. The further away you are, the more your audio source dissipates, especially in certain rooms. The larger the room, the boomier your audio will sound, as the audio is dissipating more. Also remember that your shotgun mic is much more directional than the onboard stereo mics of the H4n.
When I use my H4n for recording, I generally place the recorder as close as possible to my source. if I'm using the onboard mics only, I will place it slightly behind the PA stacks t a bout a 45 degree angle. this tends to cut down on the bass coming from the PA.
Generally I will use the built in XLR inputs and 2 mics (eitehr Rode M3 or Shure SM57) to seperatley mic the PA stack. One on the horn and one on the woofer. Then use the onboard mics (facing towards audience) to record ambient crowd reaction.
If I take a board feed I use the 1/4 inputs and not the XLR inputs. The reason for this is that the XLR inputs are balanced for mics input, and the 1/4 input is balanced for line input. Also for loud shows I tend to also use the onboard "Concert" limiter in the menu. This works pretty good.
As a whole I try not to use board feeds, becasue as was written you never know exactly what you're going to get. So I prefer to live mic my sources (instruments, PA stack etc.) as needed.
The H4n does perform well for live recording, but like anything you must learn how to use it properly in different situations and know it's limitations. As well as learn and use proper audio recording techniques.
For many who have only focused on video and are now expecting audio to be easy, they are sorely mistaken, as it's a whole other art form in which to learn.
Jay Massengill June 30th, 2010, 09:57 AM Once you pull your audio files into the computer, how are you monitoring then? (I'm at work so I can't listen to your example on youtube.)
Given that you were satisfied with the sound while monitoring during the live recording and first playback from the Zoom, and based on your description of the setup for both internal mics and the board feed, I'd first guess that there may be something else in your post-production setup that's working against you such as a monitoring problem or phase cancellation of some kind.
Can you post here a very short bit of just the board feed tracks unaltered except for cutting them down to 10 seconds worth?
Thomas Moore June 30th, 2010, 09:57 AM Thanks for the input, and in retrospecdt I should have asked these questions ahead of time, but I'm going to re-shoot both bands so this time I want to get it right.
At that time the H4N was positioned just behind and to the left of the guy in the white jacket (on the left).
Do you use the concert limiter on both the onboard and the mic's/feed?
How do you convert from a XLR input from the board to the 1/4 inputs on the H4N do I still need the pads?
Thanks!
Thomas Moore....
Jay Massengill June 30th, 2010, 10:12 AM You need standard balanced XLR female to TRS male cables in order to use an XLR line-level feed from one device into the line-level balanced 1/4-inch inputs on the Zoom H4n.
(Most mixers also have line-level outs on balanced 1/4-inch connectors. In that case standard balanced TRS male to TRS male cables are used.)
You may still need a pad for line-level but it would likely be only -5db to -10db normally. It would depend on the level coming from the device, which could range from moderate for an Aux Output that wasn't turned up full volume, to very, very hot for a main output that's being pushed hotter than normal. The H4n's line-level inputs are too sensitive to handle full +4db line-level signals. You'll need to work with the sound mixer person and the board feed ahead of time to make sure of what you're actually getting and how the Zoom is reacting to it.
I use the internal compressor on line-level signals almost all the time and it's rare that I use the internal mics. I just did recently for the first time and was very pleased.
Michael Liebergot June 30th, 2010, 10:12 AM Thomas I do sue the concert limiter even for board feeds. As i helps a little.
As for the 1/4 inputs, the H4n has a dual XLR-1/4 input. So you simply plug in a 1/4 trs input in the XLR port. As I said the XLR input pin configuration is wired for a "Line" feed. This was designed this way most likely becasue Zoom figured that musicians who generally use 1/4 inputs for their instruments, would use the H4n for line input recordings of things like electric guitars, bass etc.
And most would be using the XLR for mic inputs.
So if you are taking an XLR feed form the board, the use a XLR to 1/4 mic cable. Or make sure that you have the appropriate XLR to 1/4 adapter on hand. I always travel with every kind of adapter possible, just in case.
Thomas Moore June 30th, 2010, 11:04 AM Thanks, so for the adaptors, use these?
Monster Cable - CableLinks Adapter - 1/4" TRS - 600459 -
and add this to my kit for pads - since I already have the -40 pad
Shure - A15AS - In-Line Attenuator - A15AS - B&H Photo Video
Thanks!
Thomas Moore
Jay Massengill June 30th, 2010, 11:40 AM At work I use these cables:
XLR Female to TRS Male (http://store.haveinc.com/c-1651-xlr-female-to-trs-male.aspx)
but the adapters you listed will also work. I use cables instead of adapters because it puts a little less physical strain on the Zoom's internal connectors but generally it's not a problem with full-size 1/4-inch jacks like it can be with 1/8-inch connectors. Using a cable can also give you a little extra length if needed or it can be one less connection if you're located close to the board.
I think you'll need no more than -10db of attenuation, but there are also impedence issues to think about. Most of the readily available attenuators are designed for mic level signals and low impedence.
Others can give better technical comments on this.
Thomas Moore June 30th, 2010, 12:16 PM Thanks I like ordering from B&H so these cable adapters
Remote Audio - XLR-Female to 1/4" TRS Phone - CAXF1/4J18 -
I'm going to do another "test" saturday so if anyone has any other suggestions I'd appreciate it!
Thomas Moore June 30th, 2010, 04:03 PM Here also is a "sample" clip of what the board feed sounded like trying to make sure I got all the instruments playing in it.
Steve House June 30th, 2010, 04:15 PM Another thing to watch out for is creating phasing issues and "comb filtering" caused by different distances the performers are from the stage mics versus to the recorder with its internal mics. Every foot difference in distance is equivalent to 1 millisecond delay between the pickup on a mic up close to the performer versus the arrival time of his sound at the H4n. That much difference when the two are mixed can introduce a significant phase shift, unnaturally emphasizing some frequencies while cutting others.
As an aside, 30 feet of difference can throw sync in film or video off by a full frame, one of the reasons using an on-camera mic from the back of the house is such an incredibly bad idea - if you were 60 to 90 feet away, not unusual for an auditorium, the sound from the stage is getting to the camera 2 or 3 entire frames later than the light that is forming the images.
Bill Davis June 30th, 2010, 05:15 PM First bars took my brain right back to my first live Springsteen concert. Nov 4, 1975. Gammage Auditorium at Arizona State University. Some things you never forget.
Anyway the board feed you got is pretty typical. Most of the insturment mix is there. The vocals are obviously "dry" and they likely added reverb in the chain after the board. Unless these are on a separate recorded track, you can't add any after the fact to make the vocals settle back into the mix.
Springsteen is pretty much modern "big band" music. Which is really difficult to balance and get right in live recording. It just won't sound right unless the things that are supposed to solo and "cut through" the mix (the vocals, the horns, the SAX!!!) do precisely that. This implies someone riding gain that knows exactly who's going to play and when. Which is why the only way to get a truly satisfying recording of something like this is to do it the same way it's done for album recording. You mic everything separately and record each instrument, player and singer separately and do a precise mix in post.
There are some folks who like the binaural approach to concert recording. But for me, bands like this have a complexity that shines live, and a single position mic, or even a single position mic with some board tap assistance, will rarely result in a recording that will come anywhere near the concert experience.
To do that really requires the 64 track truck and iso everything so that you can post mix it to sound something like the power and "in your face" qualities of the real thing.
FWIW.
Thomas Moore June 30th, 2010, 09:28 PM Well we don't have the truck and I'd still really like to save this thing, plus I need to re-do it if I can't so I don't want a repeat issue anyway, and I'd like to save this footage as there is a lot of good shots in this....
Played with the board feed in Audacity and "think" i've got it balanced at least for what I got. Any ideas on how to make it better?
Jay Massengill July 1st, 2010, 02:28 PM I can definitely hear some phasing issues (both within each individual channel and between the two channels) as well as clipping where this test file exceeds full digital 0 level.
I think it sounds much better with the phase inverted on one channel when I split them apart and center each of them.
It's impossible to really know from afar what the mixer is sending you and how they are processing it that may be contributing to these phasing issues.
Plus there could be mixer output and cable wiring phase issues.
This combined with the nature of how the Zoom's built-in mics are going to record the scene with phase issues in relation to the board feed makes it even more complicated.
Just to double-check, you did record originally in at least 16-bit 48k WAV format right?
Some of the problems almost sound like mp3-type audible issues too.
I think if you use the correct pads (or a small mixer) between the board feed and the Zoom to avoid clipping, and can place the Zoom closer to the stage, then carefully adjust the timing of the 2 sets of tracks (smaller than one frame adjustments), you'll hear some major improvement.
If possible, find out exactly what mixer they are using and which outputs. It wouldn't hurt to check the polarity of their output cables too if they'll let you.
Also remember that clipping can occur at both the Zoom's input as well as in its recording level. So if your levels "look" good but you can still hear clipping, then the signal may be overloading the input and this could occur before the recording level controls on the older Zoom H4. With the newer H4n (I have both) I haven't experimented enough to know exactly where the controls take effect since I'm the person who is always feeding it a correct level signal.
It's also possible they could be clipping somewhere on their sound board, which you can't fix at all except to tell them.
Thomas Moore July 1st, 2010, 02:46 PM Thanks Jay, yea I didn't hear that at midnight last night when I first did this but yea at work during lunch I listened to it with headphones and picked up the "flanging", didn't notice any clipping though.
I think "phasing/flanging" is coming from my noise removal profile in Audacity I just ran it at default and didn't adjust it.
I'm going to attack it again tonight and I'll put up some test clips....
Yes, I did record 48K/16 bit wav format.
How do you adjust the timing of the two tracks in the zoom?
On try two I'm going to use the TRS cables suggested earlier in this thread.
Thanks!
Thomas Moore
Jay Massengill July 1st, 2010, 02:58 PM You're welcome. Yes poor noise reduction can certainly cause unintended time-based audible issues like these too.
When I referred to adjusting the timing between tracks I meant in post-production.
You'll need to be able to shift them on a much, much smaller time scale than 1 video frame, which is extremely coarse when you're talking about phasing issues.
If possible during the next setup, rehearsal and testing, use a slate clap at the main stage mic and later look at the difference in arrival time with the Zoom's on-board mics.
Bill Davis July 1st, 2010, 03:00 PM Thomas,
Neither phasing nor "flanging" should come from any noise removal process, period.
Both are TIME based effects.
Phasing takes place when one sound gets out of phase with another and either fully or partially cancels the original sound out.
You can visualize it as two tracks recording a bass note. That bass note drives the cone of the speaker out at 100 times a second. If one of the two tracks gets out of phase such that when the first track is pushing the speaker OUT - the second track is telling the same speaker to pull IN at precisely the same amplitude - and you mix those two signals - what you get is NO SOUND.
Flanging is a form of phasing where originally one dragged a finger or thumb against the FLANGE of a reel of analog tape to slow it down with respect to another playing the same content. That was the mechanical process of moving them out of phase with respect to each other, but it's possible in flanging to "keep up the pressure" such that you combine the phase effect with echo as the reel slows down enough to put the musical bars out of sync along with the track phase. Out of phase is constant. Flanging is out of phase that comes and goes and might include echo.
In practical music, however, there are lots and lots of frequencies in play, so when you get music "out of phase" it affects certain bands more than others and you get that characteristic "thin, whooshy, phasey" sound.
An application that's applying "noise removal" should be digitally re-calculating the audio content of a timeline to reduce the noise - but it would NOT typically be adding any phase effects in any form.
So you've got something else going on that's getting your tracks out of alighment. And yes, that can be as simple as the time delay between the board feed and the delay in your live recording that reflects that time it takes for the sound of the speakers on stage to reach the mics of your recording.
Good luck.
Thomas Moore July 1st, 2010, 08:20 PM Thanks for the help guys...
I actually got this to a point tonight where it sounded decent I'm too tired to put up a clip of it, but there was this god awful hiss that I just couldn't get rid of and it was intermittent as well as a 200 hz spike throughout the entire recording - watched it with Spectrum analyzer...
One thing I haven't mentioned in all this and I'm kicking myself for doing it now, is that I used house cables instead of mine which I know are shielded etc, so I'm really starting to think - correct me if I'm wrong, that some of my issues could also have been from the cables. Best way to describe it is a lot of what I feel is EMI interference.
Listened to the other bands input from the board and the vocals are mixed right in with the guitars and pushing to the limit washing everything else out (sob) so I give up trying to save this.
This has led me to decide to do the following:
Buy two Shure SM57's at 99.00 a piece this seems reasonable and will keep me from having this issue again I assume :)
Connect these too one of my camera's as a "saftey net", extra tracks to mix in if the board feed to my Zoom is good, using the TRS to TRS or worse case XLR to TRS cables that I bought (and will recieve tommorow) from Jay's suggestion earlier in this thread.
Here is where I'm really going to show my ignorance, and I need to do this Saturday :)
Earlier Mike suggested putting the Mic's "seperatley mic the PA stack. One on the horn and one on the woofer."
Wouldn't this just give me "one side of the mix?"
Also, how exactly should I place the Mic'?
Steve House July 2nd, 2010, 07:37 AM SM57's are close working stage vocal mics, fine when 2 inches from a singer's mouth but not optimum for recording an ensemble from the edge of the stage.
Thomas Moore July 2nd, 2010, 08:08 AM Thanks Steve...
From what Mike was saying, and I've found a few other references to doing this on other forums the method is to put them 3" to 1 foot away from the horn and the woofer on the PA stack...
Since there are usually two I'm not sure which one I should be micing for one and the other which no one seems to mention is "right in front aimed at the speaker, in the middle, off to one side, at an angle etc.
I'm assuming on a mic stand pointed directly at the horn, woofer...
Rick Reineke July 2nd, 2010, 09:35 AM If the mics are too close to the PA speaker, your going to get pretty much the same instrument-vocal balance as a board feed... just though a speaker. You will have to experiment with aiming and placement to get a good balance of speaker / stage / room.
Another option, If available and the house PA operator does not object, is taking a pre-fader auxiliary out which would give the option of raising or lowering the channels, independent of the FOH mix.. A post-fader aux. out would give you separate mix options as well but would be subject to the channel fader moves by the FOH mixer.
Thomas Moore July 2nd, 2010, 11:19 AM Getting the "board feed" from the speaker I believe is what I am going for here as a saftey net for my board feed.
I should be able to get the room/crowd sounds from the onboard mics of the ZOOM by putting it behind the PA cabinet - at a 45 degree angle aimed towards the crowd.
Note I'm typing this to verify as this is what I'm gleaning from all the information being suggested here.
If I get good board feed I've got I've got 4 good tracks to work with, if I don't I have the Speaker mix to use, if both come out good - I've got 4 good tracks to mix from...
Note still asking for verification of my thoughts here :)
I'm actually considering - note which means I probably am - getting another H4N and using that for the PA micing and the other one on the board.
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