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Gear / Technical Help => Ask The Tapers => Topic started by: extraordinary machine on September 29, 2006, 02:43:20 PM
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http://www.sendspace.com/file/ne3xq3 (http://www.sendspace.com/file/ne3xq3) ( jmayer2006-09-27 t09 - Clarity ( 30-sec segment ).wav )
For the record, I was around 17 rows back in a large ampitheatre and running the lineage in my sig. ( gain on jb3 @ -3db )
Maybe I'm not hearing things correctly, but this just doesn't sound right to me...
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I think you may be SOL. Too bad, aside from the distortion the recording sounds really good. You could try a HPF in post, but I think you'd have to go really high to make a difference, and even then I'd imagine you'd lose too much to make it worthwhile, but it's certainly worth a try right?
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( gain on jb3 @ -3db )
Not sure, but I don't think running negative gain on the JB3 is going to do any good in any situation? If you clip the signal going to the JB3, then take the gain negative on the JB3, aren't you just going to end up with a clipped signal at a lower db mark? You've got to prevent clipping in front of the JB3. If you're running a preamp in front, I would think you'd keep the JB3 at 0 gain. I did read here that the JB3 gain seemed to be analog, so if your preamp just can't give you the levels you want, then maybe, just maybe, it'd make sense to crank up the gain on the JB3, but not sure there is ever any benefit to running negative gain? Can anyone else confirm this?
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Not sure, but I don't think running negative gain on the JB3 is going to do any good in any situation? If you clip the signal going to the JB3, then take the gain negative on the JB3, aren't you just going to end up with a clipped signal at a lower db mark?
If the analog signal overloads before the JB3 (or as it enters the JB3), that's true - reducing levels won't resolve the issue, one would just have a distorted signal at lower dB. I don't think it hurt in this case, though.
Sounds like the mics or JB3's analog-input overloading. Three possible scenarios, I think:
<1> Mics overloaded. Given the 4061s are rated for 144 dB, I doubt it's the mics, unless...
<2> ...the mics were starved of powercausing them to overload, due to a bunk power source. Quite possible if the 6020's batteries weren't up to snuff. Were you using known-good batteries in the 6020? (And by known-good, I mean verified with a multimeter, not just "new" - I've had more than my share of bunk "new" batteries.)
<3> JB3 inputs overloaded by the incoming signal. Perhaps the AT line transformers added too much gain. Have you run that gear combo before (DPA 4061 -> MPS 6020 -> AT CP-8201 -> Creative Nomad Jukebox III) and experienced good results with the line transformers in the lineage?
FWIW, my money's on <2>.
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I've run dpa4060>mps6030>jb3 with no problems (except for a few seriously bass-heavy shows). The 4061s take a higher SPL and give a lower signal out, I can fairly safely say they're not the problem. As I understand it the mps6020 is basically the same as the mps6030 just with different connectors. Provided your battery is good I think we can rule this out also. Which kind of leaves the at cp8201... a quick google gives
" The Audio-Technica CP8201 Microphone Impedance Matching Transformer is designed to connect a low-impedance microphone to a high-impedance electronic input. The high-quality transformer solves the problem of excessive high-frequency loss and hum pickup."
So the transformers don't add any gain.. just match impedances? "input impedance 250 ohm, output impedance 50,000 ohm"... doesn't the jb3 have a nominal 13kohm input? This doesn't feel right. If you have the chance, try dropping the cp8201's and running dpa4061>mps6020>jb3. Yes, you'll need to run the jb3 gain a little higher, but I would be surprised if this combination overloads.
cheers,
stephen
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Was the JB3 set to line- or mic-in? If mic-in, perhaps that would account for the overloading.
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If you're running a preamp in front, I would think you'd keep the JB3 at 0 gain.
I left it there for Sheryl Crow's set. If I had run it any higher, there would have been noticeable clipping. At the show, I didn't want to risk it for Mayer's set, so I lower it, figuring it wouldn't hurt. ( I've done this a few times below with no real issue )
<2> ...the mics were starved of powercausing them to overload, due to a bunk power source. Quite possible if the 6020's batteries weren't up to snuff. Were you using known-good batteries in the 6020? (And by known-good, I mean verified with a multimeter, not just "new" - I've had more than my share of bunk "new" batteries.)
The battery seemed fine to me - I put it in a couple of shows ago and those had no issues. ( and I've had my share of battery problems in the past with this particular set-up )
<3> JB3 inputs overloaded by the incoming signal. Perhaps the AT line transformers added too much gain. Have you run that gear combo before (DPA 4061 -> MPS 6020 -> AT CP-8201 -> Creative Nomad Jukebox III) and experienced good results with the line transformers in the lineage?
I've been using this combo since February, and haven't had any real problems with it. ( aside from batteries [ in the 6020 ] dying on me a couple of times when they really shouldn't have )
So the transformers don't add any gain.. just match impedances? "input impedance 250 ohm, output impedance 50,000 ohm"... doesn't the jb3 have a nominal 13kohm input? This doesn't feel right. If you have the chance, try dropping the cp8201's and running dpa4061>mps6020>jb3. Yes, you'll need to run the jb3 gain a little higher, but I would be surprised if this combination overloads.
I've tried running without the transformers, and unless it was a really loud show, got no levels ( on the jb3 ) at all. ( yep, totally contradictory )
Was the JB3 set to line- or mic-in? If mic-in, perhaps that would account for the overloading.
Line-In. ( that my first thought, that I had accidently set it to mic-in in the dark - apparently not )
Oh well, from the looks of I probably won't be able to do much with these. Thanks anyway.