So I noticed when I was doing some recording that my DI box is phase reversed from my amp's DI. It got me wondering, is this a problem for live sound if I ever use that box live? Assuming my amp's DI is the same phase as it's power output to speakers.. does the PA need to be in phase with my amp? It's just a theoretical question at this point.
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My bet is that it's you bass amp (speaker) that is phase reverse , not the DI.
How did you came up with that conclusion ?
Only way to be sure is to record both DI and amp'S DI simultaneously to L-R and check phase , if they are OK then it's the amp (cab)
How did you came up with that conclusion ?
Only way to be sure is to record both DI and amp'S DI simultaneously to L-R and check phase , if they are OK then it's the amp (cab)
I ran the out from my DI into my amp, plugged the direct box into channel 1, amp direct into channel 2. Recorded both tracks. Complete phase cancellation until I reversed the polarity on one of the tracks. It's a non issue there... I was just wondering if that's a problem for live sound assuming I use the same setup but the DI is going to FOH and my amp is running on stage. Assuming the polarity is reversed to the PA from my bass amp speakers, what does that do to the sound in the room? Will they cancel out, or is the difference in position and speaker type, etc. enough to make that also a non-issue?
It can be both an issue or a solution.
Most board have a phase switch and it's the first thing any soundman will do with a bass amp on a stage.
Since the amp is on stage , the PA is a couple of feet in front , so the PA has to be delayed in order to be in phase with the backline onstage.
Most places I played , there were no delay on the PA so sometimes flipping the Phase to 180° on the bass DI will help in some cases.
Also keep in mind that a phase problem in a room is never exactly 180°
Most board have a phase switch and it's the first thing any soundman will do with a bass amp on a stage.
Since the amp is on stage , the PA is a couple of feet in front , so the PA has to be delayed in order to be in phase with the backline onstage.
Most places I played , there were no delay on the PA so sometimes flipping the Phase to 180° on the bass DI will help in some cases.
Also keep in mind that a phase problem in a room is never exactly 180°
Cool thanks, so if I understand you correctly, phasing can be an issue in any case, the reversed polarity isn't necessarily a problem on it's own?
Exaclty
In a situation where your bass amp and the PA are perfectly aligned , then it's gonna be a problem
If both are perfectly out of phase , it's a solution.
Just write on your DI 180° where 0° is and vice versa or keep that DI out of phase
As long as you know it....
In a situation where your bass amp and the PA are perfectly aligned , then it's gonna be a problem
If both are perfectly out of phase , it's a solution.
Just write on your DI 180° where 0° is and vice versa or keep that DI out of phase
As long as you know it....
