kick bin: polarity

IMO it's good practice not to have polarity reversals in the wiring. +1 on the speakon should be connected the the positive red terminal on the driver and cause the diaphragm to move away from the magnet. if the driver is mounted backwards it should be corrected by inverting polarity on the LMS.

a 180 phase shift is not equivalent to a polarity reversal - some LMS it might be approximately equivalent at high frequencies but might be way off for low frequencies. I have been meaning to measure the ultradrive phase section for a while. I have always assumed it is an all pass filter with a 2nd LPF implementation - the filter frequency adjusted to give the required phase shift at the LPF frequency for that section.

snowflake wrote: IMO it's good practice not to have polarity reversals in the wiring. +1 on the speakon should be connected the the positive red terminal on the driver and cause the diaphragm to move away from the magnet. if the driver is mounted backwards it should be corrected by inverting polarity on the LMS.

I'm with bee on this one.
I think all cabs should be set up to 'push' with normal polarity settings on the LMS.
So if the driver is reverse mounted, the wiring should be switched, on the speakon preferably.

Otherwise it's a confusing unknown if the person using the box doesn't know the driver is reverse mounted and needs to accommodate for it on the LMS.

odc04r wrote: snowflake wrote: IMO it's good practice not to have polarity reversals in the wiring. +1 on the speakon should be connected the the positive red terminal on the driver and cause the diaphragm to move away from the magnet. if the driver is mounted backwards it should be corrected by inverting polarity on the LMS. a 180 phase shift is not equivalent to a polarity reversal - some LMS it might be approximately equivalent at high frequencies but might be way off for low frequencies. I have been meaning to measure the ultradrive phase section for a while. I have always assumed it is an all pass filter with a 2nd LPF implementation - the filter frequency adjusted to give the required phase shift at the LPF frequency for that section. Might be overthinking it a tad there, more like that somewhere in the processing chain there exists a bit of code if (Sample_Invert == True)     Sample = !sample; But it would be interesting to see a transfer function of a channel with zero processing except inversion. I doubt you'd see any difference with the exception of phase.

snowflake wrote: odc04r wrote: snowflake wrote: IMO it's good practice not to have polarity reversals in the wiring. +1 on the speakon should be connected the the positive red terminal on the driver and cause the diaphragm to move away from the magnet. if the driver is mounted backwards it should be corrected by inverting polarity on the LMS. a 180 phase shift is not equivalent to a polarity reversal - some LMS it might be approximately equivalent at high frequencies but might be way off for low frequencies. I have been meaning to measure the ultradrive phase section for a while. I have always assumed it is an all pass filter with a 2nd LPF implementation - the filter frequency adjusted to give the required phase shift at the LPF frequency for that section. Might be overthinking it a tad there, more like that somewhere in the processing chain there exists a bit of code if (Sample_Invert == True)     Sample = !sample; But it would be interesting to see a transfer function of a channel with zero processing except inversion. I doubt you'd see any difference with the exception of phase. I was talking about the phase shift section which allows values from 0 to 180deg and is (according to manual) the shift at the LPF frequency for that output. I agree the polarity inversion is trivial

Ah fair play, I'm with you. Probably the digital equivalent of an all-pass filter then, wiki has a bit of info on how to derive one.