Intermittant noise using MR-1000

[RickZ]

Yesterday, I recorded a choral concert, and about and hour into the program, a spastic noise came in went. I've used this MR-1000 for lots of recordings, with great results, this is quite disappointing

Was wondering if anyone else has suffered this fate.

Thanks in advance,
Rick Z

[zeca]

Sounds like mobile phone interference.

[Corran]

Yeah that is definitely cell phone interference. You must have a bad cable or unbalanced area somewhere where it leaked in. Or someone was sitting right next to you with an iPhone (they have ridiculous amounts of interference, one would make this noise in my monitors when the person was texting 10 feet away!).

[resound]

Gotta love that GSM handshake. I'm especially amused when I'm watching or listening to a news program and a guest's phone does this.

The easiest advice is to turn your phone off during recording (if you have a GSM handset; even vibrate or silent modes leave the phone connected to the carrier's network) and to position as much of your stuff as far away from people as possible (including cable runs).

[hughesmr]

Thanks for this post ... I experienced this once with my MR1000 was was curious as to the reason for it.

Another issue: once in a while, I get a spike noise in material after I have transferred it from DSD to PCM using Audiogate. I'm at work and can't post a sample at the moment, but has anyone else had that problem? (I don't hear it in the DSD source on the Korg, only on my PC after the transfer. It is thankfully rare and I can redraw the waveform to clean it up.)

[RickZ]

Thanks for the info ! I recently added the 10m "remote cable" to my pair of MKH8040's, which is a very skinny little cable, compared the Klaus Heyne approved GAC-3 double shielded cable. Which means I may have added a 30 foot 'antenna' to my mic line. There was a large audience, with lots of people all around my mic stand, and I saw a few either shutting them off of putting them on silent, as requested at the beginning of the concert.

I will remove the 'remote cable' and go back to using GAC-3 from the microphones, presuming the MR-1000 is not receiving the interference itself.

Thanks again ! What a great resource this forum is !
Rick Z

[mr.gefell]

I was thinking the cheapo power supply might be causing various problems, might have to try the kingrex psu as an upgrade if it'spossible.

[Remoteness]

...And, this is why it should be mandatory to announce that everyone should "turn off" their Cellular phone, not just put them on vibrate.

This distinct sound has even made it on the Grammys broadcast a few years back.
I remember hearing that hand-shack during U2's acceptance speech.

[videoteque]

You can say it as many times as you want, but nowadays not everyone shuts off their cellphones, seems they can't live without it...

[Remoteness]

That's true, but you must at least attempt to protect the quality of the sound recording.

IMO, if you state the facts and they still do not turn off their devices it's on them.
If you never bother to state the facts, and that dreadful noise makes it onto your recording it's clearly on you.

[Shadow_7]

Originally Posted by hughesmr

Another issue: once in a while, I get a spike noise in material after I have transferred it from DSD to PCM using Audiogate. I'm at work and can't post a sample at the moment, but has anyone else had that problem? (I don't hear it in the DSD source on the Korg, only on my PC after the transfer. It is thankfully rare and I can redraw the waveform to clean it up.)

This may or may not apply, but the Korg manual for DSD filter says that DSD has a greater dynamic range than 24 bit BWF. And the filter takes 3dB off the DSD to ensure you don't crest those limits. I'm not sure if that just applies to headphone monitoring, but is was interesting to note. And a motivator for only recording in DSD now.

[videoteque]

IMO, if you state the facts and they still do not turn off their devices it's on them.

Of course you have to ask for it!!! It's only that it won't solve 100% of cases, unfortunately...

[hughesmr]

Originally Posted by Shadow_7

This may or may not apply, but the Korg manual for DSD filter says that DSD has a greater dynamic range than 24 bit BWF. And the filter takes 3dB off the DSD to ensure you don't crest those limits. I'm not sure if that just applies to headphone monitoring, but is was interesting to note. And a motivator for only recording in DSD now.

Hi Shadow,

I always run my peaks between -12 and -6dB in DSD to be safe. There seems to be no correlation between level and when this noise shows up .... happens even during slient passages, so it's not a recording artifact. It may be unstable power during the DSD->PCM transfer in Audiogate. Thankfully it is rare, but I'll try to post an example of it the next time it shows up.

[RickZ]

Michael,

Your reply seems to indicate that you use Audiogate with input DSD coming from file on MR-1000, and output to one of your hard drives, is that right ?

I've been in the habit of copying the DSD files to this computer, and using Audiogate to convert, with input DSD coming from one of my hard drives, output PCM to another. I've had zero problems with that method so far.

My thought was that the USB connection to the MR-1000's drive might not be fast enough to keep up . . ?

FWIW,
Rick Z

[Shadow_7]

I try to shoot for the utmost peaks at/below -3dB. But I'm using the Korg's preamps. And generally end up in the safe zone -18dB to -6dB.

I do notice a pop once in a while. It's generally when I'm moving the unit while recording. Maybe the XLR connectors on the unit. Or when I move/bump the windscreens on the mics. Also if I get the windscreens too snug to the electret business ends I get strange results. I've since snugged up the connectors on the XLR cable and otherwise avoid moving the unit and I haven't had the issue in a while. I'm also tending to keep a little more slack on the cables relative to the recorder. As much as I think my 25' cables are too long for my purposes, I'm finding more and more that they're a little short at times.

[hughesmr]

Thanks for your reply, Rick. I was indeed doing file transfers over the USB while downconverting. Tried offloading the DSD material first and then converting it to PCM on my HD. Did two complete Messiah performances this way and no pops .... but that is only anecdotal evidence for me (I'm a statistician . Hope that is the cure .... time will tell. Many thanks for the tip, though!

Happy new year! -Mike