Something most don't think about when you go for amped fronts and rear fill off HU

[eharri3 10+ year member]

It's Infinity Reference coaxials for rear fill off the HU, Hertz HSK 165s in front off a bridged EA4200 for 140 watts per side. Head unit is an Alpine 9886. Before when all my speakers were amped I had crossover controls front and rear and just started off with a gain attenuation on the rears to get the proper mix.

When I switched to running the rears off the head unit I realized I took away the amp crossovers from the infinitys and they were now running full range and distorting while the rest of the system had more to give. My head unit only high passes all four speakers at the same time as low as 80HZ. The only option to keep the rear fill playing cleanly at full volume was to use the head unit's 80HZ high pass but I believe my Hertzes are still capable of staying clean at around 70.

I know the first thing alot of people will chime in with is 'get rid of rear fill.' Im considering it but don't quite want to do it yet.

For those running rear fill off a head unit without a very flexible high pass and amped fronts, do you run your rears full range? Cross them over separately? How? Running active or some other way? Tryin to figure out the best most cost-effective way to keep the infinity reference coaxes at about or 90 HZ but take the Hertz HSKs down to about 70 at the same time.

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[SRim23 5,000+ posts]

you could buy those "bass blockers" for the rears. you can get them at BB i believe.

or also you could......... get rid of the rear fill. haha what car is it? unless its a giant suv and you care about what rear passengers think then you should just ditch them.

 

[dman4486 5,000+ posts]

I run mine faded to the front until I have passengers....then I never go much to the rear because they can only handle 10w

 

[eharri3 10+ year member]

you could buy those "bass blockers" for the rears. you can get them at BB i believe.
or also you could......... get rid of the rear fill. haha what car is it? unless its a giant suv and you care about what rear passengers think then you should just ditch them.

04 Dakota Crew CAb. Just feels wierd without my rear fill but at the same time Ive tried it faded all the way to the front so I know why so many people do it that way too. If this were some little two seater or couple the rear coaxials woulda been gone a long time ago.

 

[ultimate157 5,000+ posts]

I have a grand cherokee and my front stage is more than enough to reach the rear. Not to mention you don't need to turn down the volume every 5 seconds to hear your passengers.

 

[n2audio 5,000+ posts]

I bought myself some inline capacitors from mouser or digikey or one of those electronic component sites. I think they're 150hz @ 4 ohms (6db/oct). I might still have a couple leftovers if you're interested. With the low slope they play down to 100hz or so. They're really cheap if you buy them before they're packaged as "bass blockers" and marked up 300 or 400%. You just have to do a simple calc to find your uF.

 

[Proximity 10+ year member]

You can get inline passive crossovers or bass blockers. I'd just get those.

http://www.crutchfield.com/g_82600/Crossovers.html?search=inline&osp=&skipvs=T

 

[n2audio 5,000+ posts]

You can get inline passive crossovers or bass blockers. I'd just get those.
http://www.crutchfield.com/g_82600/Crossovers.html?search=inline&osp=&skipvs=T

Not going to work for HU power. A speaker level filter will be needed.

Plus ~265uF caps are about a buck a piece.