High Frequency Spike at 15,746 Hz? -Sound Forge - PC

Subject:High Frequency Spike at 15,746 Hz? Posted by: kleb Date:10/9/2002 2:20:49 PM Spectrum Analysis is showing that I've got a high frequency spike at 15,746 Hz on all my recordings (same place in both L and R channels). Is this a red flag? What could be causing this? I'm checking all my recent recordings, done in stereo with a pair of Shure SM81s direct to Tascam DAT or HD via M-Audio SPDIF.
Subject:RE: High Frequency Spike at 15,746 Hz? Reply by: CDM Date:10/9/2002 2:43:50 PM was there a tv monitor on in the room? Was this a mic recording? I had that happen when I was doing adr with a monitor on in the same room as the talent.
Subject:RE: High Frequency Spike at 15,746 Hz? Reply by: kleb Date:10/9/2002 4:08:04 PM No, TV monitor not in the room. Yes, stereo mic'd w/ the SM81's. Recorded in 2 seperate rooms, same result. TV may have been on in the family room. I'll run some more tests.
Subject:RE: High Frequency Spike at 15,746 Hz? Reply by: Phyphor Date:11/6/2002 11:15:25 PM Probably electrical noise from some other source. Are your mic cables shielded?
Subject:RE: High Frequency Spike at 15,746 Hz? Reply by: John_Cline Date:11/7/2002 3:26:32 AM At that frequency (actually 15,734) it was almost certainly a TV that was on somewhere. John
Subject:RE: High Frequency Spike at 15,746 Hz? Reply by: kilroy Date:11/7/2002 9:47:26 AM Ok, now here is something for you. Check out the tune Sledgehammer on Peter Gabriel's superb So album. There is a shaku sample at the beginning of the song sourced from an old Emu Emulator II sampler. There is also an impressive spike, like the one you describe, at 15630 hz. Using any high amplitude, low sample\bit rate samples in your recording? These kind of spikes were fairly common on the old Emu or Mirage samplers especially in the upper limit of their useful sampling frequency ranges. Try recording some high gain silence to determine whether it is your audio path or not. If it is, then try doing the same again only removing (one at a time) each piece of gear you would normally employ in your recording procedure until you isolate the offender. Cheap sound card perhaps? Good hunting.

Subject:High Frequency Spike at 15,746 Hz?

Posted by: kleb

Date:10/9/2002 2:20:49 PM

Spectrum Analysis is showing that I've got a high frequency spike at 15,746 Hz on all my recordings (same place in both L and R channels). Is this a red flag? What could be causing this? I'm checking all my recent recordings, done in stereo with a pair of Shure SM81s direct to Tascam DAT or HD via M-Audio SPDIF.