Taperssection.com

Gear / Technical Help => Ask The Tapers => Topic started by: beatkilla on June 20, 2017, 01:14:20 PM

Title: What is wrong with this wave form?
Post by: beatkilla on June 20, 2017, 01:14:20 PM
i don't recall ever seeing my wave form looking like this?
Title: Re: What is wrong with this wave form?
Post by: ilduclo on June 20, 2017, 01:45:32 PM
looks unusual all right, have you got a short wav form sample you could upload? I'd like an even closer look (and a listen). Couple of minutes long should be good enuff
Title: Re: What is wrong with this wave form?
Post by: rocksuitcase on June 20, 2017, 01:50:25 PM
That is two channels out of phase with each other.
Title: Re: What is wrong with this wave form?
Post by: morst on June 20, 2017, 03:58:12 PM
I am not familiar with the app but the waveform looks perfectly normal to me.

what is "wrong" with it or different about it?

Does it sound weird?
Title: Re: What is wrong with this wave form?
Post by: beatkilla on June 20, 2017, 05:22:20 PM
I am not familiar with the app but the waveform looks perfectly normal to me.

what is "wrong" with it or different about it?

Does it sound weird?

Well I acquired a used sonic studios preamp to use with my sonic mics and during testing of the preamp on playback I noticed that when i got close to my front door there was hum or feedback every time I got close to that door or also a window..... strange so when I saw the weird looking waveform I wondered if that was a give away to what the real problem is with this hum or feedback?
Title: Re: What is wrong with this wave form?
Post by: mfrench on June 21, 2017, 12:21:09 PM
is it a 1/8" stereo mini connector at the preamp?
Title: Re: What is wrong with this wave form?
Post by: KISSFAN on June 21, 2017, 01:07:50 PM
I am not familiar with the app but the waveform looks perfectly normal to me.

what is "wrong" with it or different about it?

Does it sound weird?

Well I acquired a used sonic studios preamp to use with my sonic mics and during testing of the preamp on playback I noticed that when i got close to my front door there was hum or feedback every time I got close to that door or also a window..... strange so when I saw the weird looking waveform I wondered if that was a give away to what the real problem is with this hum or feedback?
curious if this file was put through another program like Adobe Audition before being opened in Waveditor? I wonder if there was a botched copy and paste in Audition that was then saved, before the file was opened in waveditor? just a thought. I have never seen this before. curious what the outcome is.
Title: Re: What is wrong with this wave form?
Post by: rocksuitcase on June 21, 2017, 01:13:33 PM
I use CDwav editor and that waveform does not appear "normal" to me. It may not be 2 channels "out of phase" which should have been written "polarity reversal".  which if 100% true (making one channel 180 degrees "out of phase" with respect to the other channel) would result in no sound. I stand corrected by myself and morst as in it doesn't appear to be reversed polarity- now then what do we think it is?.

So, phase issue it doesn't appear to be, but it does look odd. What are you getting at Moke? that the 1/8 inch connector on the pre-amp may be incorrectly pinned? (or the adapter cable used)
Title: Re: What is wrong with this wave form?
Post by: mfrench on June 21, 2017, 01:39:58 PM
Weirder things have happened with 1/8" mini jacks/cables.
Amongst a multitude of other issues, phase issues can arise if there is any micro-shorting between positives, intermittent grounding issues, etc.
When I read Sonic Studios, my mind took me to mini-jacks, immediately.
Title: Re: What is wrong with this wave form?
Post by: beatkilla on June 21, 2017, 01:44:07 PM
The mics and pre connect via mini xlr but the pre output is mini 1/8.
Title: Re: What is wrong with this wave form?
Post by: mfrench on June 21, 2017, 02:27:06 PM
If all else fails, try setting up, and messing with that/those connection(s) while recording something, and see if you can replicate it that way.
Title: Re: What is wrong with this wave form?
Post by: anodyne33 on June 21, 2017, 02:30:36 PM
That is two channels out of phase with each other.

ding ding ding
Title: Re: What is wrong with this wave form?
Post by: Gordon on June 21, 2017, 05:00:13 PM
That is two channels out of phase with each other.


that's what it looks like to me as well.
Title: Re: What is wrong with this wave form?
Post by: mjwin on June 23, 2017, 06:08:10 PM
This sure looks strange but, peering closely, I think the weirdness is actually an artifact of the screendraw algorithm. I'm not familiar with "CD wave", but what seems to be happening is that, rather than drawing a single point for each sample, it's drawing a line & "filling in" between the sample and zero, kind of like a bar chart. So every sample point above zero becomes a solid bar from zero up, and every point below zero becomes a solid bar below.

What gives this away is the perfectly flat edges at the zero point. Also, the fact that, if you imagine the outline of the waveform, ignoring all the green fill-in. it actually looks ok.  The problem we see here is probably just the result of looking  closely at a quickly drawn waveform which is simply intended as a rough indication of what will be burned to the CDR.

So, even if you use the app quite often, you might not notice this anomaly until you start to zoom in (like your screenshot) I reckon that if you zoom right in, it might be easier to see exactly what's happening. 

It's probably worth loading the file into another audio editor - Audacity, or anything you have kicking around, just to see what that makes of it, though.

BTW, I think your "hum" issue is completely separate, more likely to be connector/ ground related as has been suggested already.

It's intriguing though...
Title: Re: What is wrong with this wave form?
Post by: djphrayz on June 23, 2017, 07:12:42 PM
What is the source?  Are you testing your setup by placing your rig in front of your own speakers or is this a recording of a live show?  Tell us more...
Title: Re: What is wrong with this wave form?
Post by: vanark on June 23, 2017, 07:21:49 PM
Or just reverse the polarity on one channel to see what happens
Title: Re: What is wrong with this wave form?
Post by: morst on June 25, 2017, 03:05:53 PM
That is two channels out of phase with each other.
I think I only see one channel, how can one channel be out of phase?


Well I acquired a used sonic studios preamp to use with my sonic mics and during testing of the preamp on playback I noticed that when i got close to my front door there was hum or feedback every time I got close to that door or also a window..... strange so when I saw the weird looking waveform I wondered if that was a give away to what the real problem is with this hum or feedback?
House wiring forming a radio transmitter near the walls and doors?
Title: Re: What is wrong with this wave form?
Post by: rocksuitcase on June 25, 2017, 03:25:41 PM
That is two channels out of phase with each other.
I think I only see one channel, how can one channel be out of phase?


Well I acquired a used sonic studios preamp to use with my sonic mics and during testing of the preamp on playback I noticed that when i got close to my front door there was hum or feedback every time I got close to that door or also a window..... strange so when I saw the weird looking waveform I wondered if that was a give away to what the real problem is with this hum or feedback?
House wiring forming a radio transmitter near the walls and doors?
CDWav displays its output as only one stereo waveform. This is because it is an editing program and does not require being split out into two in order to cut tracks.