Headunit thoughts (EQ/x-over related)

rscecil007 · Post by **rscecil007** » Thu Jul 09, 2009 5:38 am

So I'm looking into headunits for my new system and been doing a lot of reading and research here, on diyma, etc. Trying to get caught up on all the new tech as I've been out of the car audio hobby for almost a decade.

Current system plans (most is already sitting in my office) are some Hybrid components up front running active off a Ti 500.4, and a Ti 600.2 bridged to a single JL 13TW5 in a sealed box. Got a DD10 as well I recently got a good deal on, not sure what goodies I'll be hooking up to that.

I've got a new bodystyle Tacoma access cab, which has the double din opening. Looked at some double din units simply b/c they look nice installed, but I really don't care about the DVD or nav elements, so just decided to go with a nice SQ single din unit.

The three I've been looking at are the Alpine 9887, Eclipse 5030, and the Pioneer PRS-800. The Alpine 9887 seems nice for the money, does a lot, and has a lot of EQ and crossover options. The Eclipse and Pioneers look nice as well with their own pros and cons obviously, but I keep coming back to the Alpine the more I read on it. FYI, I most likely will not use the Imprint on the Alpine, and I don't have an Ipod, but will need an Aux input however for my Zune (I know this takes an extra cable you have to buy for the Alpine).

One major concern is, as I understand it, if I am running my fronts active off the 500.4 using a single 2 ch RCA, will I still have full or partial use of the EQ's in the headunit? A friend told me it's nice to be able to sit in the drivers seat and adjust all the cross over and EQ points on the fly, which makes sense. I know the crossover in the HU won't be used if I'm using the ones on the amp. And I know from what Stipud told me the Ti's have really good x-overs in them, so I hate not to use them. So I'd like to be able to use the EQ's in the headunit if possible while running the crossovers on the amp, just not sure if this can be done (sorry if that is a lame noob question.)

Another reason I like the 9887 is the defeatable power in the head unit. It will most likely be another few months before I get the funds to complete and fully install my system, but I could go ahead and get the 9887 now, be enjoying it and using it to power the factory speakers, then turn off the HU amplification when I get my amps hooked up.

Any thoughts on this, or reasons NOT to go with the 9887? I learned a lot since I joined here a month or so ago, and know you guys are really know your stuff, so any help or opinions are appreciated. Sorry for the long winded post as well. Thanks!

davewaibel · Post by **davewaibel** » Thu Jul 09, 2009 6:03 am

your right to not use the imprint- its DSP crap- as far as playing with crossover points, its kind of bag of snakes, and you may never get done fiddling with it, also the slopes of most hu crossover points are usually marginal at best- of the three decks your looking at I would say that I think the eclipse is probably the best of the group, if you ebay the piece you will probably get it for what its worth- as far as being able to turn amplification on or off, it doesn't really make much of a difference on the group that your looking at- in a real 'sq' deck, your looking at outboard, power supply and the ability to turn the 'display' on the deck off to eliminate as much signal noise as possible- so in your instance if there is a little amplifier chip running or not, it isn't going to make much of a difference between the units. Have fun, there really isn't much of a pig in the bunch-

dwnrodeo · Post by **dwnrodeo** » Thu Jul 09, 2009 6:17 am

My previous install was a Pioneer PRS-880 running a Ti500.4 active using only a single two channel RCA. I used the Ti's crossovers to run the active settings for the comps and used the deck's EQ to fine tune everything. I really liked that setup and am having difficulty replicating the SQ in my current install using passive crossovers. (Need a x10 multiplier on my Roadster!!!!) Use the amps crossovers and the deck's EQ. It will be more of a hassle tuning it because you'll have to keep going to the back of your vehicle to adjust the settings on the amp, but once they are set you won't have to adjust them and can fine tune the EQ from your front seat.

rscecil007 · Post by **rscecil007** » Thu Jul 09, 2009 6:29 am

Awesome, thanks for the responses, this helps alot.

Also, if there's another deck you think might be worth looking it, I'm all ears. Sorry, but that nice Denon STROKD has is out of the question.

Post by **stipud** » Thu Jul 09, 2009 6:43 am

I personally think that deck EQs are, for the most part, completely useless.

Adjusting an EQ requires proper measurement tools or you will probably end up making your system more bloated if you don't know what you are adjusting. When most people EQ by ear they just set it in a smiley face curve, with too much bass and treble.

What you need to do with EQ is hook up a real time analyzer (RTA). This is a microphone that measures and graphs the response of your system. You play pink noise over your speakers, which has an equal quantity of sound per octave. The RTA microphone reads this in, and it is translated into a graph that shows the frequency response of your system. Frequencies that are too loud, you need to reduce with your EQ, and frequencies that are too quiet, you need to increase. What this ends up looking like on the EQ is not a curve, smily face, or anything close to that... it's a whole lot of jagged up and down, where you tame all the peaks and valleys that are caused in the difficult acoustical environment of a car.

Doing this by ear would take years of experience in knowing how flat installs sound, and memorizing several songs with a wide distribution of frequencies. It's not something I would recommend doing willy-nilly.

Imprint tries to automate this process. It measures the frequency response of your system and tries to automatically tune for it. It also individually pulses the speaker, and measures the time it takes for the sound to reach the microphone. This way it can do your time alignment as well. Generally it doesn't work the best, but it's far better than a shot in the dark.

I would personally use a headunit with the LEAST bells and whistles. With your 500.4, all you need is one pair of RCAs, and you can run your whole system off of its crossovers. If you want equalization, get a good analog 30 band EQ like the TiEQ30 or an AudioControl unit. Then source an RTA (your local audio shops SHOULD have one), and tune your system the right way.

rscecil007 · Post by **rscecil007** » Thu Jul 09, 2009 7:11 am

Ah, also good to know. I hadn't done much reading on how to properly EQ a system, but I knew there was more to it than just adjusting the points on the fly by ear, especially an untrained ear.

Well, going with this method, maybe the Eclipse would be a better bet for me then. Cheaper overall as well.

I suppose now I'll have to read up on that TiEQ30 and see what those go for these days...

dwnrodeo · Post by **dwnrodeo** » Thu Jul 09, 2009 8:29 am

I'm not sure about the eclipse, but the Pioneer has an Auto EQ/TA feature that I have found pretty helpful. The EQ isn't perfect, but it gets close enough where you can adjust it to where you like it from there. It has a 16 band L/R equalizer which should be sufficient.

Post by **stipud** » Thu Jul 09, 2009 8:34 am

dwnrodeo wrote:I'm not sure about the eclipse, but the Pioneer has an Auto EQ/TA feature that I have found pretty helpful. The EQ isn't perfect, but it gets close enough where you can adjust it to where you like it from there. It has a 16 band L/R equalizer which should be sufficient.

Yeah I had this function on my DEX-P1R. Good for filling huge voids in your system response but not as good as properly tuning with an RTA. Probably not as good as imprint, since that is a far more modern technology... however you don't have to pay to use someone else's, you just plug the mic in and away you go!

Of those three I like the Pioneer the best, though that is just personal bias. Currently I run my stock headunit, which has balanced outputs that I convert to high voltage RCAs for my amp.

Post by **ttocs** » Thu Jul 09, 2009 8:36 am

stipud wrote:I personally think that deck EQs are, for the most part, completely useless.

Adjusting an EQ requires proper measurement tools or you will probably end up making your system more bloated if you don't know what you are adjusting. When most people EQ by ear they just set it in a smiley face curve, with too much bass and treble.

What you need to do with EQ is hook up a real time analyzer (RTA). This is a microphone that measures and graphs the response of your system. You play pink noise over your speakers, which has an equal quantity of sound per octave. The RTA microphone reads this in, and it is translated into a graph that shows the frequency response of your system. Frequencies that are too loud, you need to reduce with your EQ, and frequencies that are too quiet, you need to increase. What this ends up looking like on the EQ is not a curve, smily face, or anything close to that... it's a whole lot of jagged up and down, where you tame all the peaks and valleys that are caused in the difficult acoustical environment of a car.

Doing this by ear would take years of experience in knowing how flat installs sound, and memorizing several songs with a wide distribution of frequencies. It's not something I would recommend doing willy-nilly.

Imprint tries to automate this process. It measures the frequency response of your system and tries to automatically tune for it. It also individually pulses the speaker, and measures the time it takes for the sound to reach the microphone. This way it can do your time alignment as well. Generally it doesn't work the best, but it's far better than a shot in the dark.

if you are not going to compete there is no need for all this. I like EQ's as I can tune the sound to what I like and its not normally a smiley face. I know I am not tuning it for flat sound, I am tuning it for what sounds good to me, the most important person that rides in my car.