OT: Capturing seminar Audio, device ideas?

ken c wrote on 7/4/2005, 6:05 AM
Hi all -- In case my videographers get lousy audio at a 2 day seminar I'm holding, I want to have a backup sound capture device for this 12-hour day event ... ideas?

Appreciate it if anybody has a recommendation on a device (like a digital/ mp3 recorder w/attached mic) that I can sit on the stage near the speakers, to at least capture some audio, in case the wireless lavaliere has too much noise, or some other snafu?

I know mic'ing it will be a challenge (ideas/specific mic suggestions?) ...

Basically I need something I can use to record 2 12-hour days of audio only, so I've got an audio stream I can import into Vegas in case the audio on the main video is poor/noisy...

Would have to sit it on the stage edge, and have it recording while the speakers are talking, as a backup?

or, any other ideas? I don't want to have each of my 14 speakers need to wear two wireless lav mics/battery packs, so looking for a backup "onstage recorder" for hopefully < $500 or so, I can use?

(also thx to those who'd sent me demo discs, appreciate it, will keep on file for future events, I have 2 more seminars coming sept/oct this year in denver)

thanks,

ken

Comments

Spot|DSE wrote on 7/4/2005, 8:01 AM
One of the Olympus recorders set to slow record (digital) would work pretty good, but you'd likely want to use a different mic. Can you tap into the PA system/mix console? There are also in-line step down boxes that are similar to active DI boxes, that can go between PA speaker and your recording device. It's important you get this right, since there is a fair amount of voltage in that speaker line, and if not stepped down to line level, will smoke your recording device.
It also might be possible to take a headphone out of any wireless device that might be in use for the presenters, feeding the line out to the sound system and stepping down the headphone feed to allow input to a recording device like an iRiver, Olympus recorder, or other digital recording device.
Two key things:
1. Device must be digital so wow/flutter aren't an issue.
2. Device must be capable of longer record times so you're not worrying about changing and logging tape too often.
B.Verlik wrote on 7/4/2005, 11:46 AM
The cheap way I'd handle it would be to bring a VCR with HiFi capabilities and set it on SLP and record two 6 hour tapes each day. Maybe you could get lucky enough to get an RCA feed right into the unit. You should know the VCR well enough to use it under these conditions. I've never noticed any problems with wow and flutter using a HiFi VCR, but having the right level feeding into the unit would help especially since most VCRs won't let you adjust the volume. Another helpful idea from "EL-CHEAPO"
earthrisers wrote on 7/4/2005, 2:13 PM
One possible caution about using VCR...
That's an analog medium, not digital, so there could be minor variations in speed & duration, on playback -- very minor, but potentially enough to throw the sound out of synch with your separately recorded video, especially if the video is mostly people talking (because when speech is even a tiny bit off from the movement of a person's lips, the out-of-synchness is quite obvious).
farss wrote on 7/4/2005, 3:47 PM
Not exactly el-cheapo but the Edirol R4 lets you record 4 separate tracks of audio, has pretty decent mic preamps and will take a LANC feed from the camera to switch it into record.
ken c wrote on 7/4/2005, 3:53 PM
hey thanks all, solid tips... yeah I'd tried that w/VHS recorders before but it did lose sync during the last 30-40 minutes, tried that last year.. w/video signal ... so digital recording is needed...

thx Spot re that idea, will look into it...

I'm wondering, hey if I get some of those mp3 personal recorders (like a Rio?) would those work, if I set up an amped mic, maybe like the Rode one, attached to them? I could then usb-connect the mp3 recorder to a laptop every couple hours to offload the mp3s/clear memory... that's all I can think of ..

anyone know a bit better high-tech digital audio recording device, sub-$500 that I could use?

thx all,

ken
GlennChan wrote on 7/4/2005, 4:44 PM
In a bad case, a minidisc will drift 1 frame every 15 minutes or so. Even digital recorders have drift.
The drift is very consistent though, so it's not hard to fix.

2- Do you have a laptop?

3- Are you renting?
PhilCT wrote on 7/4/2005, 5:42 PM
My standard anwser would be to use a wireless sytem with a headphone out. I would connect the headphone out to a minidisk. But your comments about the RIO have me interested, I recieved a IRiver 20GB IPOD knoeck off for Father's Day. It has a biult in mic and can double as a recorder. It also accepts a line in signal when you buy the base station. The unit lists for $300 US.

sounds like a nice experiment.....
Phil
DavidMcKnight wrote on 7/4/2005, 5:53 PM
Today I sprung for two IRiver iFP-899 1GB recorders - less than $200 each at Best Buy. I will couple those with either a Rode VideoMic, mixer aux send, or a lav mic, depending on what's needed and they record for some ridiculously long time.

I did this because at an event I worked Saturday, one minidisc/mic combo failed on me (my fault, and I HATE when it's my fault.....) and the second minidisc got left behind at the event. DOH! It was not my day, that's for sure.

ken c wrote on 7/5/2005, 10:46 AM
hey sounds interesting, let me know how it goes... I want to get these backups for event recorders... great to have a second audio stream in case the first one's hosed...

people forgive mediocre video, but Not mediocre audio, for whatever reason..

dmcknight, looks interesting,
http://www.iriveramerica.com/prod/ultra/800/ifp_899.aspx

comparing w/5 gig rio:

http://www.digitalnetworksna.com/shop/_templates/item_main_Rio.asp?model=267
looks like rios don't have ext mic inputs though, so they're out.
just called rio, they confirmed none have external mic inputs. oh well.

looks like you've got the right answer, dmcnight eg an iriver w/rode ext mic.. thx..! (hmm do they work ok? never heard of the brand...)


ken
Chienworks wrote on 7/5/2005, 11:46 AM
I'd go for the iRiver units. I don't have one myself yet, but i've been spec-shopping for some time now and it looks like iRiver has more features and usability than anything else in it's price range. It's very open and will record standard .wav from line or mic in and let you dump the digital file without any compression or other futzing.

A 40GB hard drive unit is within your price range and would allow over 65 hours of CD quality .wav recording. A 5GB solid state unit would allow over 32 hours of mono 22 KHz, which is probably quite sufficient for speech, or over 16 hours of mono 44.1KHz.
ken c wrote on 7/5/2005, 1:58 PM
Hi Chienworks, thanks.... hmm I just bought the iriver 899 one at best buy ... not sure what voice settings to use..

for voice settings, the specs claim it'll do 288 hours at 8kbps ...

I'll assume I should record at 44/48 ... though I'm not sure what the difference between the KHz and Kbps means in terms of encoding?

I should go learn more about audio I guess ... :p I know when I record into cool edit 2k, I use a 48000 sample rate... on this type of unit, not sure how many hours I'd get at good quality...

appreciate if anyone can give me a clue about this stuff, I'll read up on it too.. re best Kbps I think should be 48k+ ..

hey if anyone can help, let me know, here's the 3 parameters:
on instruction manual, p 5-22:

Linein recording mode:

-Mono or stereo (I'm recording voice, so I'll use mono, right?)
- then two sliders with KHz (eg 44.1 KHZ) and
KBPS (eg 128 KBPS) ...

I know herz/frequency response, and bits per second, what that means, but I what I don't know is, hey for good quality audio What should I set those two parameters at? and how many hrs recording would I get with a 1 gig device?

appreciate any help, chien or pmasters, you guys know more about this than I do...


ken
Chienworks wrote on 7/5/2005, 2:08 PM
Kbps and KHz are not dependant on each other. KHz is the sampling rate, how often the sound is converted into digits. Kbps is how many bits the sound is squeezed into when compressing it. If you are recording uncompressed .wav files then you won't be using a Kbps setting at all.

I would guess that the voice setting they specify is intended for note-taking rather than quality and would probably be slightly garbled and harsh to listen to. At 8Kbps it's probably recording to .wma or mp3 at a very high compression level. Just for comparison, a mono CD quality track would use about 689Kbps, if it had a Kbps rating, which it doesn't because it's uncompressed. But, as you can see, the 8Kbps setting is squeezing a huge amount of the data out. The more the signal is compressed the worse it will sound.

If you do want to record compressed probably the minimum setting you should use is 128Kbps for mono or 256Kbps for stereo.

Sample rate isn't terribly critical. Vegas will automatically resample to the project/render settings for you. 48KHz will give slightly better high-end response than 44.1KHz, but the difference will probably be beyond the range of the microphones anyway so it most likely won't matter.
DavidMcKnight wrote on 7/5/2005, 2:22 PM
Ken,

I haven't had a chance to try these out yet, but here's some info I've found on settings with an external mic -

(all of this comes from a forum, none of it is my personal experience yet)

====================================================

The input is stereo and the mic mono. My iRiver (model 790) has to be in stereo mode to record from an externatl source (like a mic). Check yours first to see if it can recognize the mic in mono. If it can use mono. Otherwise you have to pick the Left (channel 1) track in your editor.

Under the ";Control Menu" set to
d) Line-in/Ext. Mic.


The settings I used are, Iriver setting for the groom, ";mono,44.1 khz, 160 kbps, mike volume set to 60";.
Minister, ";mono,44.1 khz, 160 kbps, volume 50";.
Speakers, (the Iriver was set up on a free standing microphone stand), ";mono,44.1 khz, 160 kbps, volume 60";.
I set the volume on the minister at 50 because he was fairly loud (most of them are, never have problem hearing the minister). I set the volume on the groom and the speaker at 60, I wanted to be sure I would be able to hear the groom, bride and the speakers.
=====================================================

Ken,

most all of the above I am assuming was for a lav mic. Giant Squid makes one specifically for the iRiver and will allow mono recording. I haven't gotten mine yet, so I can't attest to the quality but they are supposed to be pretty darn good for $25. I am also curiousl to see how I will use this with a mixer's output if there is indeed no way to monitor the recording level. But, hopefully the above information will get you started.

- David

ken c wrote on 7/6/2005, 7:59 AM
Thanks, David, I'll test those out, using the Rode mic ... will let you know what I find.. should be a good backup audio recorder .. thanks much..

ken