Running a mic and DI (especially in the studio) seems to be pretty common these days. Unless you happen to get very lucky with mic placement, wouldn't there be a problem with phase issues? I guess I am wondering why it seems to work?
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DI & Mic create phase issues?
- Thread starter Jazzman
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billfitzmaurice
Commercial User
- Sep 15, 2004
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Many engineers will use the DI for the lows and the mic for the mids and highs, with no overlap, and that takes phase issues out of the picture.
and assuming they don't do it that way, it's very easy to fix with modern boards. when i blend, phasing has been a non-issue 100% of the time.
scotch
It's not rocket science!
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A simple phase reverse on the console or mic position change generally solves the issue.
Mic placement is key.
If you want to solve any issues with hardware, however, you can get a phase alignment box, such as the Little Labs IBP or Radial Phazer.
bongomania
Commercial User
My soundman just mentioned to me the other day that he gets phase problems when he equals the volume from my DI and live mic. We're talking live shows here, not recording. He has to keep one of the two slightly beneath the other level-wise to avoid the sound thinning out.
We're probably going to add a Radial Phazer to the board gear to fix this. Its the perfect solution. Anyone use one of these live?
We're probably going to add a Radial Phazer to the board gear to fix this. Its the perfect solution. Anyone use one of these live?
scotch
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90% of the time, the 180' phase reverse works. If the phase is off 90' or so, you get less benefit. For a typical gig, it's probably most pragmatic just to favor one source over the other. In a recording studio, it gets trickier - but usually they have the equipment on hand.
I agree. It can help get you closer if you are way off. You have to use a proper combination of mic placement and the phase switch. With a simple 180 degree phase it will be hard to get it 100% accurate. The Aphex deal would be perfect.
hmm.....tricky.
I agree 100% with the phase reversal tip,however - for true subterranean bass,try using a sennheiser 609 placed a metre back from the cab for your bottom end and use the DI for your highs and mids.
of course use only subtractive eq when using computers
and if you have time,the arcane science of microphone placement will help create for you the holy grail of recording :: vibe!
I agree 100% with the phase reversal tip,however - for true subterranean bass,try using a sennheiser 609 placed a metre back from the cab for your bottom end and use the DI for your highs and mids.
of course use only subtractive eq when using computers
and if you have time,the arcane science of microphone placement will help create for you the holy grail of recording :: vibe!
Why so far away? PLEASE don't say low-end needs the distance to develop, or something like that.
billfitzmaurice
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+1. For below 100 Hz a DI works best, as it gets around the low end deficiencies of most cabs and mics and eliminates stray low frequency noises and vibrations. And there's no benefit to a mic down there, as there's no such thing as tone in those frequencies. Tone is defined above 100 Hz, so that's where you run a mic, to capture the tone of the amps and speakers. A meter away is best if you have tweeters, to allow integration of the tweeters and cone drivers, but if it's woofers only close micing is better, again to keep extraneous noise out. And if you use the DI only below 100 Hz and the mic only above 100 Hz there is no phase problem.
Speaking of which, phase interactions with multiple sources take place over all 180 degrees. A 'phase reversal' switch is actually a polarity switch, so the options are either in phase at 0 or in phase at 180. That leaves 179 degrees unaccounted for, so it's not a perfect solution by any means. Eliminating bandwidth overlap of the DI and mic does the trick, with only a polarity switch necessary for perfect integration of the two sources.
"Best Post of the Week". Thanks, Bill. Clear, concise, and makes perfect sense--which almost disqualifies it as a TB post.
Reverse the phaze only could works when the two signals totally out of phaze. Phaze correction tools like Radial, are more sophisticated tool. When mixing a record, adjust the phaze is more easy with the DAW software, because you just have to zoom the view, you can see the two waveforms, and move it to match. In my experience the piezzo and the mic signal are never in phaze, sometime just need, very little correction, but it can really improve the sound.
