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I have a PDX M6 which I just realized today doesn't seem to have any way to bypass the built-in crossover. I have it set at 400hz and then I'm low passing again with my Bit 10 at 80hz. Am I forced to set the Bit 10 to full pass and use the crossover on the amp for it to sound right?

On another note, I have just a single RCA from the Bit 10 sub-out to my M6. The sound is lacking in a major way since putting in the Bit 10 (I had a lc2i before) and I'm not sure if it is the RCA cables (no y-adapter) or the crossovers. I'll probably have to go try to get a y-adapter tomorrow. I am using the high level inputs by the way.
 

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Don't bother buying a Y-splitter, just turn the gain up. Assuming the M6 sums the two input signals, turning the gain up will have exactly the same effect.

The undefeatable LPF set to 400Hz is going to have no audible effect on sound below 80Hz where your sub is playing, so I wouldn't worry about it. It may have a slight effect on phase, but your ears won't know any different.

Assuming you are low passing your sub on your processor somewhere between 60 and 80Hz, you might actually want to set the LPF on the amp somewhere around 120Hz to increase the rate of roll off above that point to help your sub 'dissapear'. This may have some effect on phase, but again your ears are unlikely to know the difference.

Do make sure you set your TA first by measurement and then tune the TA by ear to account for the phase changes caused by all of the following: crossovers in your processor, crossovers in your amp, the subsonic filter on your amp, passive crossovers, your speaker enclosures, and your speakers themselves.
 

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Don't bother buying a Y-splitter, just turn the gain up. Assuming the M6 sums the two input signals, turning the gain up will have exactly the same effect.

The undefeatable LPF set to 400Hz is going to have no audible effect on sound below 80Hz where your sub is playing, so I wouldn't worry about it. It may have a slight effect on phase, but your ears won't know any different.

Assuming you are low passing your sub on your processor somewhere between 60 and 80Hz, you might actually want to set the LPF on the amp somewhere around 120Hz to increase the rate of roll off above that point to help your sub 'dissapear'. This may have some effect on phase, but again your ears are unlikely to know the difference.

Do make sure you set your TA first by measurement and then tune the TA by ear to account for the phase changes caused by all of the following: crossovers in your processor, crossovers in your amp, the subsonic filter on your amp, passive crossovers, your speaker enclosures, and your speakers themselves.

Hold on wait your saying that phase has no effect on the sound?
 

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Don't bother buying a Y-splitter, just turn the gain up. Assuming the M6 sums the two input signals, turning the gain up will have exactly the same effect.
:rolleyes: So much for RTFM...

http://support.alpine-usa.com/products/documents/OM%20PDX-M12_M6.pdf said:
NOTE:
The following troubles may occur when it is not
properly connected.
1) One side input results in low output.
2) One side input will cause failure.
3) One side input may cause more heating
and thus result in the earlier operation of
overheating protection.
Do yourself a favor and buy the splitter.
 

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Hold on wait your saying that phase has no effect on the sound?
Not at all! Phase can have a completely catastrophic effect on sound - play two equal sounds 180 degrees out of phase and you have no sound whatsoever!

It is questionable whether or not the human ear can detect phase shift on its own, but when combining sound from multiple drivers, attention MUST be given to phase. This is exactly why we use TA and why I advocated tuning TA by ear.

I am suggesting that when you have phase shifts on account of 7 different components of your system (6 listed in my previous post, plus your equalizer), the value of eliminating just one of them might be quite limited.

It is because of this complexity, that I advocate tuning TA by ear (as do many others)
 

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:rolleyes: So much for RTFM...
Sorry, I haven't read the manual for every amp on the market. (this is not my amp)

Please note that statements I make that begin with the word 'Assuming' are assumptions. These should be validated (perhaps by reading the manual) ;)

It does seem strange that Alpine would sell an amp that would be damaged by using only a single input without providing either a mono/stereo input switch or a $3 Y splitter. I think this is a little dissappointing.
 
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