Novice trying to hook up EQ/aux input

[blomster]

Note: For some reason I can't include links to anything... sorry. My post gets rejected when I do.

I've got a 1998 Honda Civic (DX), and recently the cassette adapter I'd been using to hook up my MP3 player went on the fritz. Since the sound was terrible anyway, I thought I'd make a project out of adding an aux input to the factory radio. After a bit of looking around, I decided against getting a new head unit, because I couldn't find any that were basic enough. I don't want a USB port, SD card slot, CD player, or even a radio for that matter (and no, I can't just ignore the features I don't use, the simple fact that they're there annoys me). Ideally I just want an aux input with a volume knob, and maybe a few EQ knobs that I can twiddle. I discovered saw the Clarion EQS746, and thought I had found perfection. So I ordered it.

Sadly I suffer from a touch of dumb, and I didn't realize there was a difference between preamplifiers and actual amplifiers. Obviously (in hindsight), despite the fact that my EQ unit amplifies the signal voltage, it doesn't have the power to drive speakers. After I realized this, I tried various schemes to install my new EQ unit anyway, primarily by attempting to hack apart the 8-pin DIN cord from the old cassette deck and use it to connect the EQ to the factory radio (which clearly has some kind of basic amp in it). For reasons documented elsewhere, this didn't turn out to be as trivial as I thought it would be (there's a communications protocol between the cassette/CD player and the factory radio that must be adhered to, otherwise the radio won't allow you to switch to the tape deck input).

So as far as I can tell I'm left with three options...

1. Buy a premade aux input adapter for a 98 civic (PIE HON-AUX 1992-2001, ~$50). I'm pretty confident this would work, and I presume I could hook up my EQ in front of it, but it's the most boring solution. And for $50, it's not particularly cheap for what it does, and I'm guessing that going through the factory radio isn't the best thing for sound quality.

2. Buy a head unit with preamp outs/ins. I'd prefer not to get a new head unit... I'm somewhat worried about theft, and I think they're almost all ugly and bloated anyway.

3. Get an amp. This would avoid the factory radio... On the other hand, most amps look like total overkill for my purposes. I don't want my music super loud, just loud enough to hear comfortably while driving on the freeway, and installation for most amps looks intimidating at best (I haven't done any of this before), given that they're big and from what I've read are supposed to be installed in the trunk.

I've found the Pyle PLMRMP3A 4-channel (marine) amp, which I guess I'm ok with pricewise (also ~$50)... would this be powerful enough for my front/rear speakers? Would it result in better sound than using the factory radio amps through the converter I linked to in option 1 above? Does anyone know of another amp in the under $70 price range that I could install without having to run wires under the carpets to my trunk, drill holes in various places, and potentially run into power issues with my battery?

I haven't ruined anything too horribly yet (except the old tape deck, that's in pieces), so I wanted to double check here to see if anyone had any suggestions for the simplest way to wire things up that includes the EQ. Thanks in advance for any help!

Click to read more...

 

[subzero 5,000+ posts]

get a new deck. detachable face

 

[blomster]

I'd really prefer not to get a new deck, they're all ugly and have too many features. Given that the factory deck must have some amp(s) in it, and it isn't very big, are there any small 4-channel amps that I could install somewhere behind the dash? All the amps I've seen are as big as the entire factory radio.

 

[maylar 10+ year member]

Note: For some reason I can't include links to anything... sorry. My post gets rejected when I do.

I believe the forum has a 10 post minimum before you can upload anything.

OK, so you have a factory radio with cassette, right? Would the Clarion EQ fit in the dash instead? If yes, then adding a small amp like you suggested would work. You'd connect your MP3 source to the aux input on the EQ and let the amp power your speakers. I'm not a Pyle fan, but whatever.. it's cheap. Amp in the glove box or wherever you can fit it (typically the trunk) with RCA cables between the EQ and amp. You'll also have a cable dangling out of your dash for the MP3 player. Ick.

Honestly, the adapter seems like the best route. Dunno what you'd do with the EQ though.. return it or sell it here?

 

[blomster]

Thanks for the advice. I've already removed the cassette player (separate from the factory radio) and put the EQ where it used to be... I tried hooking it up too just to see but predictably there was almost no sound. Do you think I could hook up the EQ to the adapter unit, set the fader on the EQ all the way towards the front, and use it as the aux in? Cable coming out of the dash for the MP3 player is unavoidable regardless I think unless I get a bluetooth adapter, but I'm not too bothered by this... I've mounted a half-DIN pocket above the EQ in the DIN-sized slot that used to hold the cassette player, and I'll drill a hole in the pocket and run the cord out through that... can stow the cord there when not in use.

I'll probably go with the adapter, since that seems like the only tractable approach for me at the moment... I'm just surprised that there aren't any small amps I could mount behind the dash that would do the job for me so I can avoid the factory radio altogether. What do they use as amps in the factory deck and why can't I find those amps packaged separately somewhere?

 

[DUAL10S 10+ year member]

You are correct, you will have to buy a amp and rewire all of your speakers but it can be done. I would not put the amp in the dash anyway, somewhere it can get some air flow (under a seat).

If you are going to bypass the factory radio you dont have to run a 4 channel amp. Just get a 2 channel amp that is stable at 2 ohms stereo (most are). Put the front left and right on one channel and the rear left and right on one channel (bridge @ 2ohm). Just make sure you have 4 ohm speakers. You will loose some of the fading (front to rear or can be left to right if you choose) but it will get a signal to all speakers.

Most of the overkill look of a amp is the heat sink. If ya check out some of the amp gut pics there's not much on the inside of the 2 and 4 channel amps in your price range.

Just guessing here but the factory radio is prob putting out ~25 watts per speaker (if that) so jumping up to 50 watts isn't going to be too loud. If it is just turn down the volume.

I have done this and works great.

If you have already wired the eq up then the amp will be no problem. I think you can get away with 8g wire at this power level and will have little impact on the elec system. Also, you can run your mini jack cable from the dash to under the seat and up between the cushions (no wire hanging out of the dash). If you go this route you can use anything with a headphone jack and it will play on your system. You do not have to put your amp in the trunk. Under a seat is fine (not the best location but it will get dirty)

Hardest part will be hooking the amp up to the speakers. Will have to decide to run new speaker wire or try to splice into the factory wire. For simplicity I would run new wire. But if you already know which wires are speaker wires it may be easier to splice in at the factory radio. If you do this leave enough wire to rewire back to factory just in case and dont cut the factory speaker connectors off, just leave them hanging in the doors.

If you want it to sound better (i assume thats why you bought the eq) and not necessarily louder this is a great time to upgrade your factory speakers. Just remember ya get what ya pay for. I would look through the threads and decide on what amp and speakers ya want.

 

[srb 10+ year member]

If you don't want to install an amp, your best option sound quality wise might be the Nakamichi CD400

https://www.woofersetc.com/p-760-cd400-nakamichi-sound-quality-amfmcd-player.aspx

Yes it does have CD player and radio, that you didn't want, but it also has an AUX input, superior sound quality and styling perhaps more to your liking.

It is expensive tough ($289)

 

[blomster]

Thanks, DUAL10S... that was helpful. I'm actually somewhat leaning towards getting an amp, but I'm hoping to avoid the more involved aspects of the installation such as redoing parts of the electrical system. I looked for a while to find the specs of the factory stereo, but I can't actually find how many watts/channel the factory amp puts out (though 25 sounds like a pretty reasonable guess). I was considering a 50 watts/channel amp, something like the Alpine MRP-F300. Do you think I'd be ok running this without modifying the electrical system? You mentioned e.g. using 8g wire, which surprised me a little since the harness for the factory radio uses something like 16g wire for everything from power to speaker signals... what would the consequences of using the stock wiring with a 50 watt amp be? (I know what wires are connected to which speakers, and if/when I replace the speakers I can get adapters for the factory speaker harnesses, so running new wires would actually be more of a pain than using the stock wiring.) Thanks again for the feedback!

 

[DUAL10S 10+ year member]

No problem.

First thing - Alpine anything is gonna be better than the Pyle amp you mentioned earlier.

Second - the 8g wire is for the Power and Ground wires - speaker wires should be fine @ 16g. 8g should be the min for the amps in this power range and this will have to be run from the batt (+) to the amp (+) power input. Dont forget to install a inline fuse around a foot from the battery. If you have decided on a 4ch amp more than likley you are gonna be running @ 4 ohm x 4 channels. Based on the listening volume you described I really dont see a problem with the elec system. Keep in mind some of those rms rating are @ 14 volts. If ya are @ 12v gonna be a little less rms power. Even if ya do go with 2 ohm speakers the elec should be ok at the volume level you are talking about.

Agree it sounds like it wil be easier to splice into the factory wiring. But just so we are clear, there cant be any kind or signal coming from the factory radio to the speakers. This is the main reason i suggest to run new wire. Dont want to risk hooking a power wire to the amp outputs. Also, does your MP3 have FM? Because the only signal going to the speakers has to come from the amp. The only signal to the amp will come from whatever you plug the mini jack into (ipad, phone, mp3, laptop etc.....)

I know it may seem like a pain to run new wire but you will have peace of mind knowing the connections are correct and will probably eliminate any kind of engine noise. On that note dont skimp on the ground connection - keep it short and get all the paint off before installing the ground wire. And dont skimp on the RCA cabels as well - get some good quality cables. If ya ever decide to pull the system (sell the car) a quick reconnect and ya got a working factory stereo (will help if ya trade it in later on) ya never know. And you still got all your gear for the next vehicle. Wish I would have done mine this way.

Those three wires (power, ground and remote) that make the EQ work are the same ones that will make the amp work. If you are gonna leave the EQ installed in the dash you can just piggy back the remote from the EQ to the Amp. All that does is turn the EQ and Amp on when you turn the key. Will just have to run a larger (8g) power and ground wire because the amp will be pulling more current. We are not talking a multi amp setup with 4000wrms install here so, long story short you dont want the power wire insulation melting off and starting a fire with too small a power wire. Not trying to scare ya but it could happen if you dont use the correct size wire. So as you go up in power you will have to take the wire size up to the point some systems will requre multi alt's and several runs of 0g wire.

Hope that helps

 

[maylar 10+ year member]

Looking at eBay for something cheap, one of these is basically the same as the amp in a typical head unit/radio:

Rampage by Audiovox 4-Channel Hi-Fi Power Car Amplifier | eBay

You could power that from the same wires that powered your factory HU.