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View Full Version : EQUALIZER - what type of system benefits from this? should i!??



srch4aresn
05-31-2013, 05:26 PM
what type of system benefits from using an equalizer? im in the middle of buying / installing my system for my new car and would like to know if my setup would benefit from adding one or if it would not be worth it.

head unit: alpine 9887
fronts: hertz hsk 165
rears: jl cw-650
sub: dc lvl 4 in bandpass
amp1: sundown 125.4
amp2: sundown 1500.1

im asking this because i dont know if adding an eq would defeat some of the items i already have. like im expecting to get the question "why get a 'sq orientated' head unit with EQ features with component speakers but control everything off an external EQ? kind of defeats the purpose"

trumpet
05-31-2013, 05:51 PM
The 9887 is a nice head unit but it's getting old. In my opinion every system would benefit from a good EQ, and I prefer the JBL MS-8. More EQ bands to adjust is both good and bad, but the MS-8 can do an excellent job of automatically EQing the system. You change the auto-tune results to suit your tastes with the 31-band graphic EQ. It isn't good for 100% of the systems out there but yours doesn't look unusual.

NFrazier
05-31-2013, 08:44 PM
if you don't have access to an RTA or similar equipment, the MS-8 is a good option with it's auto-eq features. really a headunit can only do so much for audio adjustments. your components and your car have unique properties which are translated in sound. Everything, taken as a whole, will have inherent peaks and valleys - an EQ will help you to curve some of those peaks and valleys to have a better overall sound - more importantly a smooth sound transition between the frequencies.

keep_hope_alive
05-31-2013, 09:26 PM
the 9887 has a 5-band parametric EQ. it is plenty. IMO if you need more than that, your installation is not up to par. running the front components active will offer more benefit than buying a fancy EQ. passive crossovers are too generic to be of much use in most vehicles. the crossover point needs to be adjusted for the installation and speaker locations. i've corrected most of my issues with simple crossover point and slope adjustments.

i used to have an Alpine PXA-H701. with multiple 31-band EQ channels (basically per driver) i found myself using it too much instead of fixing the install. now that i've eliminated external processors and spent more time on the speaker install, i'm much happier, my soundstage is better, my tonality is better, and my RTA results are better. i'm never done, and after changing speakers i need to re-evaluate placement and crossover points. i seem to find improvements every day, and using an EQ is not one of my steps.

a basic EQ cannot fix phase interference because the filters aren't steep enough. trying to do so will result in very unnatural sound since you attenuate everything around the actual problem without eliminating the problem and it's harmonics. modern processors aren't good enough. for example, in 2002 when Geoff Martin helped Bang & Olufsen design their first OEM automotive sound system for a Audi A8, he needed 285 digital filters on 14 speakers (ref: IEEE Spectrum 02/2013). he basically attacked resonance issues by applying very sharp filters at the fundamental.

having an RTA at my disposal and hundreds of hours of time experimenting i've found that an EQ is not necessary if you choose the correct drivers for the intended location, and do what you can to turn that location into a proper speaker enclosure. these days, i use 2 of the 5 bands in the HU. one of the 2 is to fix a 125-140Hz resonance in the floor. the other is to compensate for my crossover point overlap.

when installing speakers in a car, you ARE the system designer. you control every aspect of the system. attack it as if you were building floor standing towers for your home. would you start with a hollow, reverberant shell of thin metal full of holes and put a thin plastic cover on it? nope. so our #1 (http://www.caraudio.com/forums/usertag.php?do=list&action=hash&hash=1) goal is making the airspace behave acoustically and structurally like a very rigid and well damped enclosure. my build log (and even the Scion tC) is an evolution, and doing it step-by-step allows for evaluation of each step. in the end, all of the steps (damping, stiffening, absorption, and seals) are required for good performance. if you knock on any part of the door and it still sounds like a car door, you're not done. :)

the other major challenge is where we put speakers and where we sit. being off axis from speakers, having speakers aim at reflective surfaces (glass), and having the speakers lack a unified acoustic center (convergence of each speakers' axis) - is car audio's largest obstacle. overcoming them requires a full custom build with lots of fabrication. not impossible, but certainly not practical for the majority of people.

keep_hope_alive
05-31-2013, 09:28 PM
...anyway...

assuming you install all of the speakers properly, your biggest issue will likely be the difference in tonality between the front and rear speakers and the use of passive crossovers that aren't tailored to your install. an EQ will not fix that.