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-   -   Help with audio at reception (http://www.dvinfo.net/forum/all-things-audio/495833-help-audio-reception.html)

Eric Aumen May 12th, 2011 08:31 PM

Help with audio at reception
During my last reception I used an h1 at the dj board to record audio. I was not monitoring it, and of course, the audio was great for 5 seconds then got extremely distorted. I was wondering if i could take a feed from the board using rca to 1/8 into my sennheiser wireless transmitter and use the receiver into the xlr input on my h4n to monitor the board feed? I would think the main issue would be making sure I was not on the same channel as the wireless microphone for the speaker, correct? My younger brother is my 2nd shooter and he knows more about audio, but I would like to come up with a better system than our last wedding. I was also thinking about using a videomic in front of a speaker as a backup. What are everyone's thoughts?

Greg Miller May 12th, 2011 09:03 PM

Re: Help with audio at reception
I can't count how many times someone has posted about a similar scenario: the board feed was OK at first, then became distorted. I doubt that anyone would set up a camera on a tripod and expect it to run itself throughout the course of a wedding or reception! Why do people expect to set up an audio recorder and expect it to do well on "auto-pilot"? Aargh.

However, as to your specific idea about using a wireless mic to monitor the board output...

I don't think that will necessarily help you. It's entirely possible that the board output is always clean, but that as the output level goes up, it causes the input stage of the recorder to overload and distort. Monitoring the board output with a wireless mic would not tell you about that problem.

Indeed, you might use a wireless link on the output of the recorder... that would more likely tell you when the recorder is distorting. Even so, it might mean the headphone output of the recorder is distorting, although the recording itself might still be clean.

I think the best solution (aside from having someone responsible for monitoring the recording) is to be sure the recorder is able to handle the output level from the board. That's tough, because many people here have stated that the board output is going to go up... and up... and up... as the event progresses, crowds get noisier, etc.

With all due respect to your Zoom, I think it's especially suspect in this situation. I have never been able to find a comprehensive manual for this gadget, only a one-sheet "Quick Start Guide" which is essentially devoid of any actual technical information. (If you have found an actual manual, please post a link!)

Furthermore, the H1 has only one input jack, labeled mic/line. That's ridiculous, because mic level requires relatively high gain, and line level requires relatively low gain. I don't see any mention of a mic/line gain switch anywhere in the Quick Start Guide, so this is just asking for trouble. If the jack has enough gain to work with mics (I assume it does) then line level signals can probably make it distort very readily. You'll never know unless you're monitoring the machine during the recording session.

I will give the same general advice that you would have found in the numerous other threads about this same issue. (1.) If you set gain before the event begins, make sure the recorder is showing a fairly low recording level... perhaps -12dB or lower. That might help, although it won't prevent the recorder's preamp from clipping. (2.) If you need to set the recorder's gain much lower than 50%, then you should use external pads between the board and the recorder, to drop the signal down to a level which the recorder can more likely tolerate. None of this will guarantee a clean recording next time, any more than you can guarantee someone won't bump a tripod and ruin your shot, if you leave the camera running unattended. You really need a combination of #1 and #2 (above) plus a dedicated audio operator. Even so, a bad board op can ruin your recording in ways that are completely out of your control.

Don Bloom May 12th, 2011 10:23 PM

Re: Help with audio at reception
Greg hit the nail on the head. Maybe I'm old school but I need to monitor my audio. I stopped plugging into the DJs boards years ago.I use a Senny E604 drum mic with a plugin transmitter set to -6db back to my receiver and on the camera I use an AKG Blueline hypercaroid set to -10db and I will say that the system works just fine for me with no clipping or distortion except for the DJs that don't know how to use a mic when they talk which only happens very very rarely and very little work for me in post.
I understand the need at times for running something like the Zoom H1/2/4 and infact I'm getting a couple for a particular job I have coming up where they are the tool of choice BUT it's all talk and no loud music so it will be fine. For music, nope, I gotta hear it. If I need to adjust on the fly then I can.
The last time I plugged into a DJ board (not a sound board run by a professional sound guy at a seminar) I got screwed by a non professional who thought 10 on the meter was the starting point and ruined not only a lot of audio but a lot of ears.
My opinion, forget plugging in, get a Sennheiser or Shure drum mic, get a plugin Xmitter for you receiver and go that route. At least YOU get to control YOUR audio.
Oh yah get a decent set of headphones if you don't already have 'em!

Eric Aumen May 12th, 2011 11:36 PM

Re: Help with audio at reception
Greg, I was asking for help on a way to monitor audio remotely. I totally agree that monitoring is necessary, but that was my first wedding ( did it for free) so I am still learning the best way to do things. Don, will the drum mic allow me to record audio coming out of one of the speakers? I have the ew g3 series wireless kit, so would i just need the mic and the skp-100 transmitter? Thank you both for your help and advice!

Eric Aumen May 13th, 2011 02:06 AM

Re: Help with audio at reception
Greg after re-reading your post I think you may have misunderstood me. I was asking if its possible to use rca to 1/8 cable to go from dj board to the wireless transmitter i would normally use for a lav mic and send the signal to the receiver. Then i could monitor the audio through h4n. I apologize if this idea is rediculous.... Just curious if its possible?

Peter Riding May 13th, 2011 04:10 AM

Re: Help with audio at reception
Eric, I see no reason why you couldn't do that but it may not be the best solution given that you personally are trying to shoot unrepeatable events and you don't really want to be breaking off to monitor the audio if you can avoid it.

The sound quality from the H1 is easily good enough for wedding work and the price of the units is so low that its affordable to use several of these devices preset to different levels. As you'll know, if you're recording a couple and officiant with an H1 hidden in a flower arrangement a few feet from them the levels need to be about 75/100. But if you're recording music from near a speaker the levels may need to be 12/100 or even lower, and if you're feeding off the board anything can happen. I set up 2 or 3 units with different levels and select the best in post.

You can sync the tracks in post very easily using Plural Eyes, then just use the parts you want from each device.

I have a Senn G3 but its gathering dust :-)


Don Bloom May 13th, 2011 05:54 AM

Re: Help with audio at reception
Eric, I place my E604 anywhere from 3 to about 6 inches from the DJ speaker. Sometimes I move it back another couple of inches but that's just a quick simple way of adjusting the levels. I grab the mic stand as I walk by it and move it.
I try to keep things fairly simple when I shoot, including all of my audio hookups and frankly the less I have to depend on other people the happier I am. As you already found out things go wrong at live events and the client doesn't care nor do they want to hear WHY it happened or WHOSE fault it was. Actaully if it has ANYTHING to do with video (including the sound thats supposed to be with it) and it goes bad, it is YOUR fault. To say to the client,' Well the DJ gave me the wrong feed or he turned the levels up too much", it's your fault. PERIOD. whether it really is or not.
Your choice, plugin and maybe take a chance, don't and its all in your hands. Either way, monitor with headphones. the next client migh not be so forgiving.

Greg Miller May 13th, 2011 08:24 AM

Re: Help with audio at reception

Originally Posted by Eric Aumen (Post 1648689)
Greg after re-reading your post I think you may have misunderstood me. I was asking if its possible to use rca to 1/8 cable to go from dj board to the wireless transmitter i would normally use for a lav mic and send the signal to the receiver. Then i could monitor the audio through h4n. I apologize if this idea is rediculous.... Just curious if its possible?

Eric, I more or less answered that. You can use a wireless system to monitor the output from the board. That will not tell you whether your recording is distorted. I want to stress that point, because your original post began by complaining that the recording got distorted "after 5 seconds." So yes, you can use a wireless system to monitor; NO, that will not tell you when your recording is distorted.

Since the output from the board is line level, and the wireless input is mic level, a simple cable will not be sufficient. You will also need a pad there, to prevent overloading the wireless system itself. You will also probably need to block the DC power (which the wireless system provides to power microphones) from getting back through the pad/cable into the mixing board. This is a somewhat minor concern, but in theory you should do this, too.

It seems a shame to use the H4n just as a monitoring device, as you suggest. The H4n at least has published specs, and a line level input that's separate from its mic input. If you're going to connect a recorder at the sound board, you might be better off using the H4n (and its line level input) rather than using the H1.

Eric Aumen May 13th, 2011 04:50 PM

Re: Help with audio at reception
Greg I was planning on using the h4n as a recording device, not only a monitoring device. I think last time my mistake may have been I used a 1/4 to 1/8 adaptor to 1/8 into the h1. The mic/line input on the h1 is confusing.

Greg Miller May 13th, 2011 05:42 PM

Re: Help with audio at reception

Originally Posted by Eric Aumen (Post 1648913)
The mic/line input on the h1 is confusing.


I think it's a shame that Zoom has not seen fit to publish more of a manual for that gadget. Many people have said they like the H1, and it can probably do a number of things pretty well. But lacking a manual, the user has to resort to trial and error.

Having just one input, and calling it "mic/line" is especially poor. It would be very difficult to design an input that has enough gain for a mic, and yet does not not distort with a line level input signal. Zoom should be ashamed for not making that clear to the users. When feeding the H1 from any line level source (like a mixing board) you are undoubtedly much safer if you have a pad between the board and the Zoom. Without a pad, the Zoom itself is likely to distort internally, even if the board signal is clean.

In general, with a lot of equipment, and lacking any detailed specs, I think the "half scale" rule can be useful. If you have to turn the input level (recording gain) down below half scale, it would not hurt to put a pad ahead of the device (and then increase the recording gain control to compensate for the pad).

Now, that's a very rough rule of thumb, and it makes the assumption that having a tiny bit more noise in the recording is a lot better than having the recording distorted to the point where it's not useable. Detailed specs and a good manual would be better than this generalized rule. But since there are no detailed specs with the H1, this rule might be a good starting point.

And keep in mind that, with events like this, as the event progresses, and the crowd gets noisier, the DJ will have to turn up his levels so that the sound system can be heard. A recording gain setting that looks correct before the event begins may easily result in distortion later on. So during the pre-event sound check, try to set your gain so your peaks are reading about -12dB (hopefully that will be safe). And, as I said above, if you need to turn the Zoom's recording level lower than about half scale to achieve that -12 level, then it would probably be wise to insert a pad between the board and the Zoom.

Sorry if I'm being repetitious, but you haven't had a lot of experience with sound, and you've had one bad recording event, so I want to be sure that you "get it" about this very important issue of levels.

Good luck!

Eric Aumen May 13th, 2011 07:15 PM

Re: Help with audio at reception
I dont mind the repetition at all Greg. I love forums like this that are filled with information. Thank you for explaining in such detail. I have a better understanding now.....
I think maybe zoom should include a pad if they want to continue to use the 1 input as a mic/line and of course a manual!
Thanks again for the help! I have a wedding tomorrow and I will be much more prepared this time.

Greg Miller May 13th, 2011 08:46 PM

Re: Help with audio at reception

Originally Posted by Eric Aumen (Post 1648929)
I think maybe zoom should include a pad if they want to continue to use the 1 input as a mic/line and of course a manual!

Yes, indeed. Years ago (this was the analog era, before digital recording), I recall some consumer recorder came with an in-line pad... in other words, a patch cable with a pad built in. That solved the mic/line problem for that device, and such a simple cable would be a big help with the Zoom.

Unfortunately, there are many different definitions of "line level" from about 0.1 volt up to 2 volts. That's a range of 26 dB. So clearly no single pad would be the right value for every situation. But it would be a step in the right direction.

For your wedding tomorrow... Hopefully you have found some sort of pad to use between the DJ board and the Zoom. If not, ask the DJ if he can give you an output with its own master, separate from the master for the PA system. Set the recording gain control on the Zoom to about 50%. Have the DJ adjust your feed so it produces a level of about -12 dB on the Zoom's recording level meter. Then pray that the DJ won't raise the levels more than 12 dB during the event.

Good luck!

Deborah Gallegos May 13th, 2011 09:02 PM

Re: Help with audio at reception
OK, this might be crazy, but the last wedding reception I did I used a RCA to 1/8" cable from the Main Out on the mixer to my wireless transmitter. I plugged my wireless receiver into the camcorder I was using and monitored it with headphones. The audio turned out well and I was able to adjust as needed all night.

It seems like that is not the correct way to do it, though, from what I'm reading here?

Thanks for any input,

Greg Miller May 13th, 2011 11:29 PM

Re: Help with audio at reception
What you did might have worked the last time, but might not work the next time. There are too many variables.

It depends on the sensitivity of your wireless transmitter, and the output level of the mixer.

It depends on whether the board op keeps his output levels pretty constant after the setup/test, or whether the levels go up significantly during the event.

It depends on the output level of a given wireless receiver, and the sensitivity of the given camera you use.

In general, wireless transmitters have a mic level input; most mixers have a line level output which can easily (but not always) distort the transmitter's input. But some mixers also have mic level output.

There's really no simple "universal" answer, except to understand the gain structure of the devices you're using, and to be prepared to add some pads if necessary. If you can monitor and adjust levels during the entire event, that's a plus. If you hope to plug in and walk away for an hour or more, that adds to the risk.

Jay Knobbe May 14th, 2011 06:45 AM

Re: Help with audio at reception
Pads? what are pads?

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