Sub pre out help

sparkymarky · 05-31-2017, 01:38 PM

Hi guys, head unit has a single sub rca out. Not an l and r sub out.

Alpine mrp-m500 sub amp says need l and r rcas connected. So ive ran a single rca back to the amp, then used a y splitter to give l and r. But now the sound of the sub sounds I dunno kind of too warbly. Is it because the l and r inout to it now has full voltages on both l and r insted of a split voltage that a head unit with an l and r sub outout would provide?

Maybe I need to redo and reduce my gains?

Go Horns! · 05-31-2017, 11:39 PM

Just plug the single RCA in to the left input. Set your gain at the max preout voltage for the head unit.

sparkymarky · 06-01-2017, 05:14 PM

Thats what i did originally but then the manual says this :
https://mans.io/files/viewer/18895/12

Go Horns! · 06-02-2017, 03:37 PM

The diagram you have is for a stereo output. But you do not have a stereo output, you have a mono output.

The amp is summing the a stereo output to make a mono output for a single speaker.

sparkymarky · 06-02-2017, 07:12 PM

Quote:

Originally Posted by Go Horns!

The diagram you have is for a stereo output. But you do not have a stereo output, you have a mono output.

The amp is summing the a stereo output to make a mono output for a single speaker.

Thanks.

So the best way for me to connect the head units mono outout to my Amps stereo inputs is?

BMW3DK · 06-05-2017, 05:32 PM

good and correct advice!

Quote:

Originally Posted by Go Horns!

Just plug the single RCA in to the left input. Set your gain at the max preout voltage for the head unit.

taibanl · 06-05-2017, 10:55 PM

Quote:

Originally Posted by BMW3DK

good and correct advice!

Quote:

Originally Posted by Go Horns!

Just plug the single RCA in to the left input. Set your gain at the max preout voltage for the head unit.

Incorrect! Did you even read the manual page? It clearly calls for use of the y adapter

I also had the 300w predecessor tk this and used the y adapter for the same reason

BMW3DK · 06-11-2017, 01:44 PM

there is a 3dB gain differance (meassured).

Y-cable can be used for extra boost, but is not needed.

have plenty of expirience with this dear keyboard warrior.

/Chris

Quote:

Originally Posted by taibanl

Incorrect! Did you even read the manual page? It clearly calls for use of the y adapter

I also had the 300w predecessor tk this and used the y adapter for the same reason

Stas2001 · 09-09-2017, 02:21 AM

Actually the same is said in specification: https://manualsdump.com/en/manuals/a...m500/284576/14

05-31-2017, 01:38 PM	#1
sparkymarky Captain 108 Rep 704 Posts Drives: BMW M4 Join Date: Sep 2013 Location: Middle earth. iTrader: (1) Garage List 2006 bmw 330d M Sport [0.00]	Sub pre out help Hi guys, head unit has a single sub rca out. Not an l and r sub out. Alpine mrp-m500 sub amp says need l and r rcas connected. So ive ran a single rca back to the amp, then used a y splitter to give l and r. But now the sound of the sub sounds I dunno kind of too warbly. Is it because the l and r inout to it now has full voltages on both l and r insted of a split voltage that a head unit with an l and r sub outout would provide? Maybe I need to redo and reduce my gains? __________________ 2014 M4. Non-ZCP. GTS EDC, DCT & Diff software with eibachs... gamechanger.
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05-31-2017, 11:39 PM	#2
Go Horns! Second Lieutenant 96 Rep 206 Posts Drives: 2013 335is Join Date: Nov 2013 Location: Austin, TX iTrader: (1)	Just plug the single RCA in to the left input. Set your gain at the max preout voltage for the head unit.
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06-01-2017, 05:14 PM	#3
sparkymarky Captain 108 Rep 704 Posts Drives: BMW M4 Join Date: Sep 2013 Location: Middle earth. iTrader: (1) Garage List 2006 bmw 330d M Sport [0.00]	Thats what i did originally but then the manual says this : https://mans.io/files/viewer/18895/12
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06-02-2017, 03:37 PM	#4
Go Horns! Second Lieutenant 96 Rep 206 Posts Drives: 2013 335is Join Date: Nov 2013 Location: Austin, TX iTrader: (1)	The diagram you have is for a stereo output. But you do not have a stereo output, you have a mono output. The amp is summing the a stereo output to make a mono output for a single speaker.
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09-09-2017, 02:21 AM	#9
Stas2001 Registered 0 Rep 1 Posts Drives: BMW M3 Join Date: Sep 2017 Location: North Carolina iTrader: (0)	Actually the same is said in specification: https://manualsdump.com/en/manuals/a...m500/284576/14
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