Connecting aftermarket Headunit to Factory Alpine Speaker question Help.

[jgscott]

I have a 02 LS Sport V8 with Alpine system. If I switch out the head unit and use a Kenwood Double Din unit. If it is only 4 channels, will it still drive the Sub amp and 2" in center console mounted factory amp'd speakers?

If so is it, because the fronts, ( front in door & Center console "2 speakers) are all tied in together ?
And same question with the rears, are the trunk amp'd Factory subs, tied in with the rear in door speakers ? Not asking about the seperate amp tie in, but instead about the wiring for front and rear, left and right balance. Aftermarket head unit only has 4 channels.

Thanks

 

[joegr]

You need the four amplified channels to drive the four door speakers. None of them speakers are tied together like you suggest.

The center two console speakers have an amplifier built into the car to drive them. You only need a line level output, but you need a center channel line level output that has a DSP setup for the layout of the car and those speakers. You won't find that anywhere, except for the factory headunit. Just leave these disconnected. That will sound better than connecting them without the proper center channel processing.

For the rear subs, you need a mono line-level sub output to go to the factory amplifier in the trunk. While it is likely that your deck only has four amplified channels, it is hard to imagine that your Kenwood Double Din does not have line level outputs for the subs. Please post the exact model number.

 

[1LoudLS]

The center two console speakers have an amplifier built into the car to drive them. You only need a line level output, but you need a center channel line level output that has a DSP setup for the layout of the car and those speakers. You won't find that anywhere, except for the factory headunit. Just leave these disconnected. That will sound better than connecting them without the proper center channel processing.

Amen!

For the rear subs, you need a mono line-level sub output to go to the factory amplifier in the trunk. While it is likely that your deck only has four amplified channels, it is hard to imagine that your Kenwood Double Din does not have line level outputs for the subs. Please post the exact model number.

yep, if it is a current model year kenwood, it will have a sub out RCA connector (all of the DNX and DDX models for this ear have front, rear, and sub outputs)

 

[jgscott]

Thanks to you both again. Kenwood Model DPX500BT.

So how is the Factory Alpine doing all front and all rear control from the F&R, L&R buttons ?

 

[joegr]

The Alpine has six audio outputs, four amplified channels (for the doors), one line level center channel output, and one line level sub woofer output. The DSP controls the audio levels out of all these channels based on you fader settings and you DSP mode selection. If you fade the front off, then the center channel will be turned down too, but if you fade the rear out, the subs will remain on.

I don't think that I understand what you are trying to get at here.

 

[1LoudLS]

Kenwood Model DPX500BT.

yes that model has three pairs of outputs (the sub output is the only one that really matters...)

So how is the Factory Alpine doing all front and all rear control from the F&R, L&R buttons ?

well the left button balances the sound from the main speakers toward the left of the car, right goes to ride side of the car.

the front and rear buttons fades the sound to either the front or rear speakers

the sub is a mono channel that does not have a separate level adjustment nor is it effected by either the balance or fade (the new kenwood will give you the ability to turn the subs up or down)

the center speakers are just for sound effects, they are adjusted by the DSP settings, the fade or balance has no effect on them.

 

[jgscott]

So if I understand correctly I can run the Subs but not the Center Console speaker with a 4 ch aftermarket unit right?

 

[regiment1]

So if I understand correctly I can run the Subs but not the Center Console speaker with a 4 ch aftermarket unit right?

You can do the center console, too. http://www.lincolnvscadillac.com/fo...tallation-Proceedure-w-front-factory-tweeters

I'm not sure I agree with joegr that they are pointless without the DSP option. If the center channel speaker on the driver side feeds the right signal, then the driver will get a stereo image centered in front of them. Same for the center channel speaker on the passenger side - if it feeds the left channel to the passenger.

 

[1LoudLS]

I'm not sure I agree with joegr that they are pointless without the DSP option. If the center channel speaker on the driver side feeds the right signal, then the driver will get a stereo image centered in front of them. Same for the center channel speaker on the passenger side - if it feeds the left channel to the passenger.

there is two problems with this theory,


first, the amp that drives them is a mono channel amp, therefore you cant send different signals to each speaker without completely rewiring them and then you will need another amp to do so.

second, there is a huge difference in distance between A: (the distance between the drivers right ear and the left center speaker) and B: (the distance between the drivers right ear and the right front door speakers) so you would have the same sound arriving at your ears at slightly different times, while your brain might not be able hear the difference (or echo) you will have certain frequency's canceling each other out giving you real poor sound no matter how good of speakers you put in their place.

those speakers were designed and placed there because of the DSP that is built into the OEM radio. without that DSP, then there is really no use for those speakers because the new radio that you are using is designed to be used with out a center channel.


now if you are really trying to get " a stereo image centered in front of them" then you need a radio with proper time alignment adjustments in its DSP. anything else is just rigging sh!t together hoping that good sound is not destroyed...
the stereos were not just thrown together on the last day of the cars design process, a lot of time and effort goes into studying the acoustic properties of the car and designing the sound system around them.

 

[regiment1]

there is two problems with this theory,


first, the amp that drives them is a mono channel amp, therefore you cant send different signals to each speaker without completely rewiring them and then you will need another amp to do so.

second, there is a huge difference in distance between A: (the distance between the drivers right ear and the left center speaker) and B: (the distance between the drivers right ear and the right front door speakers) so you would have the same sound arriving at your ears at slightly different times, while your brain might not be able hear the difference (or echo) you will have certain frequency's canceling each other out giving you real poor sound no matter how good of speakers you put in their place.

those speakers were designed and placed there because of the DSP that is built into the OEM radio. without that DSP, then there is really no use for those speakers because the new radio that you are using is designed to be used with out a center channel.


now if you are really trying to get " a stereo image centered in front of them" then you need a radio with proper time alignment adjustments in its DSP. anything else is just rigging sh!t together hoping that good sound is not destroyed...
the stereos were not just thrown together on the last day of the cars design process, a lot of time and effort goes into studying the acoustic properties of the car and designing the sound system around them.

Good info! I forgot about the center amp (even though I see joegr mentioned it above).

 

[jgscott]

Thanks to both. Another question please. If I just stay with the factory head unit and use a seperate 5 channel amp, does anyone know what the factory Alpine puts out in Volts to a aftermarket amp?

 

[1LoudLS]

Thanks to both. Another question please. If I just stay with the factory head unit and use a seperate 5 channel amp, does anyone know what the factory Alpine puts out in Volts to a aftermarket amp?

dont know it, but it also really doesnt matter too much as the levels are all adjustable. if you want to use the OEM head unit and add your own 5ch amp. then you would just use the radio's sub out (by just adding a RCA connector to the OEM wires behind the radio) and then use a 4ch Line Output Converter to get the signal for the other four channels of sound from the radios internal amplifier, i would install the LOC right behind the factory radio at all the speaker wires in the radio harness along with a female RCA connector for the sub RCA cable to plug into. then that way, if you ever do decide that you want to switch out for a new deck, all the RCA cables are already ran, and you just remove the LOD and readjust the amp and your good to go.

 

[jgscott]

dont know it, but it also really doesnt matter too much as the levels are all adjustable. if you want to use the OEM head unit and add your own 5ch amp. then you would just use the radio's sub out (by just adding a RCA connector to the OEM wires behind the radio) and then use a 4ch Line Output Converter to get the signal for the other four channels of sound from the radios internal amplifier, i would install the LOC right behind the factory radio at all the speaker wires in the radio harness along with a female RCA connector for the sub RCA cable to plug into. then that way, if you ever do decide that you want to switch out for a new deck, all the RCA cables are already ran, and you just remove the LOD and readjust the amp and your good to go.

Ok what do you mean when you say all the levels are adjustable ?

 

[jgscott]

Reason I've been asking is because here's what I'm gonna run. But I am undecided about factory head or aftermarket. I don't care about Bluetooth I use a headset, and I know how to get the Factory unit to connect mp3.

It's a Old Skool Soundstream 405s, 5 channel amp, Boston SL80 5 x 7 Plates for front speakers, and a JL Power Wedge Box with 2 10's. I think I'm gonna leave the rear doors as they are with the factory speakers.

Kinda leaning towards, leaving the factory Alpine head unit, letting the Factory system still drive the rear trunk Factory subs, and center console speakers. Using the Soundstream front channel amp to run the Bostons SL80 in front door, and SS rear chanenel for the rear door factory speakers, and the JL Powerwedge in the trunk.

 

[1LoudLS]

Ok what do you mean when you say all the levels are adjustable ?

there is a gain or level knob on amps that allow you to adjust for different input voltages

Kinda leaning towards, leaving the factory Alpine head unit, letting the Factory system still drive the rear trunk Factory subs, and center console speakers. Using the Soundstream front channel amp to run the Bostons SL80 in front door, and SS rear chanenel for the rear door factory speakers, and the JL Powerwedge in the trunk.

sounds like a good plan except for i would just remove the OEM subs. if your going to have a real set of subs, they really dont do anything anything that the JLs wont do but better. plus if you remove them, then you have a better path for the bass to get from the trunk to the cabin.