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May 25th, 2009, 03:19 AM | #16 |
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Chris,
Does your sign mixer output mic level output to the 5dmkII? and if so what is the quality like? Currently I'm having to PAD the output of my Sound Devices MixPre. thanks Dan |
May 25th, 2009, 10:21 AM | #17 |
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May 25th, 2009, 07:55 PM | #18 |
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Money no object, probably this one The 788T Portable, Multi-Track Audio Recorder with Time Code | Sound Devices, LLC
Not exactly camera mountable though. Dan |
May 25th, 2009, 10:13 PM | #19 |
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FYI - the Beachtek is available to order now from here Beachtek | DXA-5D DUAL XLR ADPTR f/EOS 5D MII/48V | DXA-5D | B&H
Dan |
May 26th, 2009, 12:30 AM | #20 |
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Unfortunately, it seems that the Beachtek has passive audio circuitry, rather than a low noise active preamp. I assume that it would work okay for high-sensitivity mics, but for low-output mics, we'd have to turn up the gain on the 5D preamps (by turning down the pilot signal), which could lead to hiss.
Currently, with my AT815b, I'm not happy with the noise into the M-Audio MicroTrack II. I'd be surprised if the 5D preamps are any better. I'm looking forward to reading some real-world tests before the Mark Free firmware makes the pilot tone solution obsolete...
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May 26th, 2009, 12:53 AM | #21 |
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Jon,
You are correct about the Beachtek's passive audio circuitry but so far I've had a high level of success with the radio mics and Sanken CS-1 shotgun on the 5dmkII, using my older Beachtek DXA-6 and a 1khz tone generator. 5dmkII with 1khz tone real world demo on Vimeo As you say I think careful mic matching will be essential, high sensitivity mics should be fine. Dan |
May 26th, 2009, 02:32 AM | #22 | |
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However, looking more closely, I see the AT815b has a somewhat unusually high output impedance, and actually so does the MicroTrack (for a mic input). I wonder if the AT815b is a transformer output mic? Somewhat skimpy specs do not say. If this were mine, I might try something like this: Shure - A15BT Bridging Transformer set to the 600:7500 position to get a better impedance match, more gain, and to improve the S/N by 6-10 db. Maybe even the higher gain setting would work. Of course the battery would need to be used since a transformer will not pass the phantom power. The A15BT Bridging Transformer is a pretty handy problem solver to have around for other uses as well. Possibly the problem is not so much the preamp as that (maybe) the mic is designed to work into a different kind of load (a transformer). Transformer input mic preamps used to be the norm in broadcast environments due to their superior noise cancellation. I notice the new version of this mic now has a lower (and more common) output impedance. Microphones are one of the few remaining places in audio where impedance matching is still important. -Mike |
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May 26th, 2009, 08:47 AM | #23 | |
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!!!
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I have done a search on this forum and am still at a loss |
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May 26th, 2009, 11:09 AM | #24 | |
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Anyway, I'm now of the mind that I want to feed my mic into a nice preamp, boost the signal, and feed it into the recorder/camera with minimal gain. I might change cameras and recorders over time, but a good battery-powered preamp can potentially outlast them all. This approach nearly takes the camera/recorder preamp out of the equation. Of course, we're still left with the anti-aliasing filter, A/D quality, clock stability, bit depth, and possible encoding (if not PCM), so the recorder still matters. But in my experience, the camera/recorder preamp is the nail that it sticking up the furthest - by a lot.
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May 26th, 2009, 11:17 AM | #25 | |
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For Final Cut, there's some software that can help to this automatically, but I'm a Vegas user on a PC. One problem is that the clock in the H2 isn't very accurate, so time can drift between the sources. On Vegas, I would sync up the sound at the start of a clip, and then stretch/squeeze the audio clip to sync up a sound at the end of the clip. In Vegas, you hold the CTRL key, grab the end of the audio clip and move it left or right, until the waveforms match. For short clips (like we do) this isn't needed. If you record a long speech, definitely sync both the start and the end. BTW, sync doesn't need to be perfect. Anything within 10ms is excellent, and within 40ms is tolerable. Also, I've tested the 5D for audio latency, and it looks to be sync'd nearly perfectly to the video. No compensation is needed on your part.
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May 27th, 2009, 03:15 AM | #26 | |
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I was just trying to figure out why that particular mic and preamp were getting along so very poorly. I think it is a good example of the old Murphy's Law corollary about 'tolerances will always add - the same direction'. ;-) -Mike |
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May 27th, 2009, 05:29 AM | #27 | |
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I don't know anything about these "preamp" devices. Would I use this with my H4n, and would it help boost the levels? |
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May 27th, 2009, 11:49 AM | #28 | |
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There are two approaches for the outputs. Some preamps put out line levels, and others put out mic levels, which are much lower. The juicedLink preamps have a mic/line switch, so it will work either way. [EDIT: The last sentence was incorrect. The mic/line switches are for the inputs, not the outputs. The output is always at mic level.] If you use a SoundDevices mixer, you would need to pad down the output when feeding a mic input (like on the 5D2.) The juicedLink preamps target camcorders, so the output is a stereo 1/8-inch jack. It's not clear if the H4n's 1/8-inch input is stereo or not. You might need to get a 1/8-inch to dual 1/4" splitter. [EDIT: The H4n 1/8-inch mic inputs are indeed stereo. Just plug the juicedLink in directly.] I plan to set mine up for two configurations: to the MicroTrackII and to the 5D2. The advantage of the Microtrack is that our audio guy can roam unplugged. For a long distance shoot, I could even have the talent carry the MicroTrackII and the preamp, rather than use a wireless connection. For one-person shoots, being able to connect directly to the 5D2 will be excellent. Actually, the juicedLink will potentially let us use even cheaper recorders that don't have XLRs or phantom power features. Personally, I think the H4n and MicroTrackII are in a no-man's-land - sure they support XLR mics, but if they don't do it cleanly, they what's the point? Anyway, I look forward to testing it. I'll post the results...
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Jon Fairhurst Last edited by Jon Fairhurst; May 27th, 2009 at 01:40 PM. |
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May 27th, 2009, 03:03 PM | #29 |
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Jon:
H4N 3.5mm jack is stereo. I used it with my stereo Sony MCS-907 two weeks ago to record live music. Definitely stereo. Dan |
May 27th, 2009, 04:34 PM | #30 |
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Yes Dan, it does output at mic level. In fact we tried at lineblevel at one point and ended up creating some noise probably due to that issue
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