ok im having a tough time hooking up my components cause they have tons of options. i just recently bought the alpine spx-177R for the front speakers and the alpine spx-17MB for the rears. in diagram A it shows 2 different ways to amp them and in diagram B shows that you can combined the crossover units of both the 177R and the 17MB together.

what should i do?

DIAGRAM A


DIAGRAM B

 

Unless you have 6 amp channels, disregard the bi-wiring in diagram A, because then you wouldn't be able to power the 17MBs.

If you only have 2 channels, you must use the single-input layout in diagram B.

If you have 4 channels, then you can bi-wire them or not. After looking at the diagrams and noticing the little jumper bars across the middle of the crossovers, I think this: It makes very little difference whether you bi-wire them or just single-wire the front components and single-wire the rears. I think there's no power exchange between the two sides of the x-over if the signal link jumpers (mentioned at the bottom) are gone.

Since there's no power exchange between the two sides of the crossover with the signal jumpers gone, why does Alpine recommend you run the wires through there at all? I figure the right side of the left crossover (bi-wiring diagram B) is just acting as a high-pass filter. It's sending the signal straight to the front components. Basically, you could bypass this step altogether by just using the high-pass filter on the amp's front channels (or your front 2-channel amp). The advantage then is those channels aren't producing low frequencies, making them more efficient for high frequencies. The disadvantage is, you may not be able to set that high-pass filter at the exact point the passive crossover is set, which is tuned perfectly for the safety and efficiency of those speakers.

The best way then, I think, is to bi-wire them as in diagram B (provided you have 4 channels) and use the low-pass filter on the amp for the rear channels and the high-pass for the front. Then you're allowing the passive crossovers to filter the signal to the front components the way Alpine sees fit, and you're limiting the frequencies the amp channels are being made to produce. Best for your amp, best for the speakers. Set the high-pass to match the low-pass setting so you don't overlap and you don't have a gap.

It would really help if you told us more about your amp though.

Nice challenge, by the way!

Dan

Edit: Hopefully someone more knowledgeable, like fcm or dc24me, can jump in here and give a second opinion.


Modified by LudemanDan at 9:06 AM 7/11/2005

 

thanks for the reply LudermanDan. i havent purchased the amp just yet but im looking at the alpine MRV-F450. its a 5 channel amp which will give me the option to run a sub later on.

anyone have any other inputs?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LudemanDan &raquo;</TD></TR><TR><TD CLASS="quote">The best way then, I think, is to bi-wire them as in diagram B (provided you have 4 channels) and use the low-pass filter on the amp for the rear channels and the high-pass for the front. Then you're allowing the passive crossovers to filter the signal to the front components the way Alpine sees fit, and you're limiting the frequencies the amp channels are being made to produce. Best for your amp, best for the speakers. Set the high-pass to match the low-pass setting so you don't overlap and you don't have a gap.

Modified by LudemanDan at 9:06 AM 7/11/2005</TD></TR></TABLE>

Dont use a lowpass on the amp for the rears unless you run into a problem with over excusion. the crossover that comes with it is a lowpass filter as it is a midbass driver. for your front speakers you'll probably want to set a highpass filter to around 60hz

I'm assuming for the time being you're hooking them up to your HU until you get an amp. if this is the case hooking them up is pretty simple. Connect the + and - on the left side of the front crossovers (SPX-177R) to the + and - on the front channels on your HU.

step 2. Connect the rear channels to the crossovers for the SPX-17MB. again + to + and - to -. basically you're using the single input from both diagrams but for diagram B you're not connecting a componet set to the high frequency terminals.

Personally i'd go against the MRV-f450 and get the MRV-F540 if you wanna stick with alpine. you reallly need more than 50W/ channel for those components.

 

What is over-excusion?

 

diagram b is to be used only if all 6 drivers are installed in the front of the car - it's done so that one set of 6.5"s can be used as dedicated midbass, have the other pair take care of midrange, then the tweeters take care of the highs...

if you want them installed in the rear, use diagram "a" for the front speakers and then run the rears to it's own set of amplifier channels. The crossover for the 17mb's probably acts as a low pass, but it's hard to tell without taking a look at it.

 

thanks for all your guys help. heres a pic of the 17MB XO unit.



i guess im just gonna run it normally. front components and rear speakers gets its own channel from the amp.