# Fitting Alpine Swe 815 Subwoofer. Problem Sorted



## lac (Jun 30, 2014)

Ok so last weekend I started fitting an Alpine SWE 815 active subwoofer. I followed the quide in the Knowledge Base. So my power , earth and switched live are working fine. It switches on and off with the stereo.
My issue is with the line level rca cables that came with the alpine set up. first i connected them up the the rear speaker inputs near the bose amp but when i connected the rca's to the subwoofer i got nothing, the subs cone was moving softly but no sound. After inspecting it , i found that if i pulled the rca's out slightly then i had bass but distorted. After speaking to the shop online who i purchased it from they said my polarity may be wrong, so i then changed the rca's inputs on the speaker wires to speaker input to earth and earth to speaker input ??? Anyway when i then reconnected the rca's fully into the subwoofer they worked but with a very low sound which was not adjustable on the alpine remote control. Ive now disconnected the cable before i smash it all up. Really stuck if anyone can help id be most appreciated.

Im using the BNS 5.0 head unit and bose. Also have a denison fitted.

If anyone has this Alpine swe 815 could you let me know how it is supposed to perform.

Ive also tried an rca line converter which didnt do anything


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## WoRkZ (Sep 19, 2015)

Have you found the solution to your problem mate?


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## SuperRS (Mar 7, 2012)

Need to change amp and headunit.

If it was me id swap the headunit, and amp, and get rid of the active sub for a normal one.


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## TT-driver (Sep 14, 2010)

Speaker level signal is normally not suitable for line input. The voltage on speaker level is much higher than the voltage on line level. 
Since your Alpine has its own amp, I'd suggest tapping signal off from the line level input to the Bose amp, rather than the speaker level output from the amp. Also, I'd take the signal from the line level that is meant to go via the Bose amp to the the front speakers . They are most likely to receive the full frequency spectrum. In some cars and brands the rear speakers don't actually receive all frequencies as the rear speakers are often smaller anyway. And obviously it allows the car brand to sell the customer some 'higher range' equipment. 
In case of Bose the rear speakers may get hardly any bass as the bass is fed separately to the subwoofer that is already there.

You need to be aware that the input has a plus and a minus. The minus is not the same as the car's earth. So don't take a short-cut there. Last but not least, the additional sub needs to be in phase with all other speakers. If it is out of phase, the additional subwoofer is working against all the other speakers instead of working with them. To change the phase, just swap the plus and the minus on the line level, on both channels (assuming the sub has a left and right stereo input) If you swap just one channel, then a lot of bass will disappear, unless the bass it only coming from one channel.

Hope this helps a bit...


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## sieuk (Mar 14, 2016)

I have the exact same sub in my car and as said above you need to tap in to the wires before the amplifier. I think the wires i used are shown below but please double check it was a while ago i did it.

11	Brown/Green	RL - (mid + tweet)
12	Red/Green RL +(mid + tweet)
13	Brown/White	RR - (mid + tweet)
14	Blue/White	RR +(mid + tweet)


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## lac (Jun 30, 2014)

Thanks for your input guys. So what i have tried so far was follow the guide in the knowledge base.
So i connected up the subwoofer speaker feed wires to the rear speaker input into the amp which where solid green with brown earth twisted around it and solid red with brown earth twisted around it. This didnt work, So this morning if tried connecting it to the rear speaker feeds coming from the amp under the rear seat which didnt work.

I will try the front speaker feeds tomorrow morning. So just to conform that i need to feed into speaker wires before they go into the amp ??


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## lac (Jun 30, 2014)

sieuk said:


> I have the exact same sub in my car and as said above you need to tap in to the wires before the amplifier. I think the wires i used are shown below but please double check it was a while ago i did it.
> 
> 11	Brown/Green	RL - (mid + tweet)
> 12	Red/Green RL +(mid + tweet)
> ...


Hi Sieuk, What you say you have done is exactly what i did this morning, But got nothing but very very soft movement of the cone. If its not to much trouble but would you be able to take a picture of your connections. just so i can follow it exact.


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## lac (Jun 30, 2014)

sieuk said:


> I have the exact same sub in my car and as said above you need to tap in to the wires before the amplifier. I think the wires i used are shown below but please double check it was a while ago i did it.
> 
> 11	Brown/Green	RL - (mid + tweet)
> 12	Red/Green RL +(mid + tweet)
> ...


I did this but no change, i noticed in one of your earlier posts regarding a remote switch that you used one from the fuse box. Now i have taken the switched live from the green/yellow feed going to the amp. Which as far as i can see is working as the blue light on the remote comes on and off with the stereo. Do you think that is working correctly . would this cause the amp not to work


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## sieuk (Mar 14, 2016)

lac said:


> sieuk said:
> 
> 
> > I have the exact same sub in my car and as said above you need to tap in to the wires before the amplifier. I think the wires i used are shown below but please double check it was a while ago i did it.
> ...


When i used the green/yellow wire mine wouldnt work correctly. It may of been that the level was very low like yours as i dont recall checking if the blue light was on or off but i wasnt getting any bass through the sub.

If you want to make sure that the green/yellow wire isnt the cause try putting a permanant live to your remote wire and see if its any louder but if the blue light is on i would of though the amp would be working correctly, if that doesnt resolve it then it has to be your inputs.

Unfortunately i cant take a picture of mine as they are all taped up to look OEM and its a right pain in the arse getting that stuff off. All i did was crimp on to the cables before going in to the amp. Trying the input via the front speakers is a good shout.


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## TT-driver (Sep 14, 2010)

lac said:


> I will try the front speaker feeds tomorrow morning. So just to conform that i need to feed into speaker wires before they go into the amp ??


Yes those coming from the HU going to the rear amp.


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## TT-driver (Sep 14, 2010)

sieuk said:


> I have the exact same sub in my car and as said above you need to tap in to the wires before the amplifier. I think the wires i used are shown below but please double check it was a while ago i did it.
> 
> 11	Brown/Green	RL - (mid + tweet)
> 12	Red/Green RL +(mid + tweet)
> ...


Mid + tweet suggests that there are no low frequencies in the signal.


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## sieuk (Mar 14, 2016)

TT-driver said:


> sieuk said:
> 
> 
> > I have the exact same sub in my car and as said above you need to tap in to the wires before the amplifier. I think the wires i used are shown below but please double check it was a while ago i did it.
> ...


I'm pretty sure those are the wires i used and mine sounds great I only have it turned up to about 60% on the remote due to the amount of bass but if unsure try the front speaker inputs as it was a few months ago when i installed mine and my memory isnt the best


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## Hardrhino (Apr 30, 2009)

As TT Driver suggests.....

From looking at the Alpine diagrams the Amp can take either high (speaker wiring) or low (direct HU to amplifier) inputs but if the speaker level input has no low frequencies then the sub will do what you say which is move a little as there's a connection but no useable frequencies.

On both sets of wiring, line in to amp and speaker outs there may be low and high pass filters.

You really do need a detailed wiring diagram of the Bose amp. Then use the low level inputs from the HU and I would suggest from above info that there may be low and high pass inputs too.


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## lac (Jun 30, 2014)

OK, So this morning i stripped everything out agin and give it another go. First off i changed the location of the earth lead. Connected the switched live to the battery to try and eliminate the switched power supply. Then i reconnected the speaker wire to my original selection which was RR L/R inputs to the amp. As in my car when I put the sound in the rear only the bass in my lower door panels run at the same time as the rear mids and tweeter, so i take it they are all connected in some way.
Anyway to cut a boring story short, I now works. So i then put the switched live back to where i originally had it connected to the green/yellow wire in the amp loom and it still works.
So im not sure what i done wrong in the first place or whether it was my earth location. But its now working.
Ive attached a few pictures below to maybe help someone out in the future if fitting one of these.

Rear Speaker inputs going to the amp.
Green / Brown is Rear Left
Pink / Brown is Rear Right
Green/Yellow Stripe is Switched Live

Earth Cable connected to lower amp securing bolt with a few washers. Black Cable


12V Power Supply Direct to battery Yellow Lead with inline fuse


Cable set back in the loom 


All Done


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## lac (Jun 30, 2014)

sieuk said:


> TT-driver said:
> 
> 
> > sieuk said:
> ...


Sieuk, What do you have your Gain / LP Filter set to as im not all that clued up with the frequencies that need to be set


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## gadgetboy38 (Mar 9, 2005)

Sorry to bring back an old thread, but how did you go about securing the speaker to the boot ?

Cheers

Charles


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## sieuk (Mar 14, 2016)

gadgetboy38 said:


> Sorry to bring back an old thread, but how did you go about securing the speaker to the boot ?
> 
> Cheers
> 
> Charles


Mine just sits in the back left corner of the boot and hasn't moved once in almost a year.

Sent from my SM-G930F using Tapatalk


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## gadgetboy38 (Mar 9, 2005)

sieuk said:


> gadgetboy38 said:
> 
> 
> > Sorry to bring back an old thread, but how did you go about securing the speaker to the boot ?
> ...


Cool cheers for that.


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## Vanu (Oct 2, 2016)

have you done any insolation on the doors? The Bose speakers in mine make them rattle when the bass is pumped up.


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