one of my issues w/ multichannel recording is an annoying option of ‘phase’. when i would playback ch 1&2 or 3&4, it sounded ‘odd’ and why i thought audacity had issues. come to find out, the tracks are out of phase. akin to having your speakers out of phase.
is this a normal thing while recording? i was trying to find ‘phase’ but ended up using ‘invert’ effect and no longer has ‘cancellations’. i don’t get this when recording in stereo from a 2 ch source, obviously.
so, is this (a) normal? (b) a bug or something w asio? or (c) something i’m doing wrong?
What are you recording? Are you using 4 microphones?
The microphones could be wired differently, or with balanced connections (XLR, etc.) a mis-wired cable can invert the phase/polarity.
Some mixers have phase/polarity switches for each input, but I’ve never seen that on on interface.
Distance between two microphones creates a time & phase difference.
Or some people put a microphone in font of a guitar cabinet and another at the back. The soundwaves from back are out-of-phase from the front.
You only get “phase problems” when the inputs are recording the same sound (like with a stereo recording where the center is picked-up by both microphones).
Multitrack recordings are usually multiple “mono” channels with a different instrument or vocal on each channel. With different sounds the phase is random enough that flipping the polarity makes no difference.
ok, here is the story. i have a 4 track cassette deck and sends the entire tape via 4ch capture card. when i process the 1st two as l&r, i get a cancellation - same w/ 3&4. so now given this happens on 1/2 and 3/4 prob rules out the deck, and implicates the software.
The software (or driver) isn’t going to “accidently” invert the phase.
It’s possible for electronics to invert and it’s not that uncommon, but an amp or preamp (or tape machine) either inverts or it doesn’t so it’s not going to invert half of the channels and everything should stay in-phase.
It might be something the original recording.
Or, what interface are you using, and what kind of adapter cables are you using?
There are some other things that can happen… A broken ground can sometimes cause L-R subtraction (like a “center-channel vocal removal” effect).
Or you can get the same issue with the wrong adapters, connecting a stereo signal to a balanced (XLR or TRS) input.
thanks for your insight - i know all too well the ‘missing ground’ theory and trs vs balanced/unbalanced, but it could very well be the capture card - maya 44 pci 4 in 4 out. never given it any pondering - now i need to.
it uses standard trs 1/4 stereo (trs but not balanced) for both inputs. and a simple rca on the other end. worst case? just use ‘invert’ on the 2nd channel. below is my card: https://www.esi-audio.com/products/maya44/
Try plugging-in one RCA connection at a time to make sure you are getting 4 separate-isolated channels. Most wiring foul-ups will give you a signal in more than one channel, or some other clue will show-up.
…I thought the hard part was getting Audacity complied with ASIO!
i kinda narrowed it down (i think) - it’s a maya44 esi issue. mme/wdm/asio - 2 ch don’t matter. still one is out of phase. i used windows sound recorder and used audacity to process - yup - still out of phase. oh well. thanks for the effort and sorry to have wasted your time and brain cells.