RyanPerrella

I have decided to replace the old speakers in my car and I guess also rewire the entire audio system. I dont know much about current audio systems so I am looking to rennlist for help on all of the components that I will need to make it work.

Ive just bought a JVC KD-NX5000 head unit and want some new speakers to go with it.

The car has 8 speakers in it. 2 about 2" tweeters in each door, next to those are a pair of 5.25" one way speakers in each door. in the back seat where your knee would be are a pair of 6.5 drivers (are these like free air subs??) and behind those on the rear qtr panel are another pair of the same 5.25" one way speakers on either side of the rear qtr panel.

So I am looking at speakers and everything I find in 5.25" is 2 way, does that make my stand alone tweeters obsolete, or do i keep them as well? I want to get some bass but dont want a box, so do i just replace the 6.5" speakers that are near the knee with something new? Is a Driver or midrange equivelent to a sub? If i have 4x 2 way 5.25" speakers, what would you put in the 6.5" hole? Do I need an amp to run the pair of woofers, or drivers, or whatever they are called?

How many amps do i need to run all this stuff. I see the head unit is 40w X 4 channel so do I need an amp to power the 5.25's? I had first thought I would simply replace speakers but it looks like i maybe getting myself into redesigning the entire thing. I want to stay with the sizes I have currently as I dont want to start drilling holes everywhere.

This is a budget system, i just want crisp sound, I see speaker pairs for $50 so I want to try and get everything I need for under $300. I also dont like all the crap speaker covers on things now, can I use just plain speaker covers?

What do most systems use now to attach wires? I noticed on the 6.5" drivers that those use RCA cables, the 5.25" speakers i think still use the old single wire connector (dont know what you call them)

And what the hell are crossovers for?

HELP!

RyanPerrella

just checked the output from the head unit it says

Power Output:200W Max. (MOSFET 50W X 4), 20W X 4 RMS

Whats MOSFET

StratfordShark

Are you sure the door mid-range and rear hatch speakers are 5.25inch? On my 88 with same 8 speaker system they are 4inch (100mm).

2-way means you can replace the tweeter but you have to feed the 2-way either with the bass/treble wiring from the original crossover or direct from head (depending on whether the 2-way has an internal or external crossover i.e 2 terminals or 4?).

But the 2-ways mostly stick out too much to use the original grills (some are OK) so you get wider choice if you choose components to replace the door mid-range and tweeters, but you should then use crossover supplied with components (this acts to route high and low signals to appropriate driver) and replace the factory crossover bolted to inside of door.

Aatos

MOSFET just means the transistor type the amplifier uses. Pretty much every car amp has them so nothing special there.

auzivision

You might look for some MB Quarts on eBay or somewhere. They come in component systems (ie separate tweeters and woofers) and look god in Porsches. I put 5.25 in the doors, but it took a little modification. I believe the OEM door speakers are 4 inch.

Shark Attack

I just replaced most of my speakers and they were almost a direct fit. I will get you mokes and modles. I uses the old grills. I did not replace the ones in the doors. they actually are in good shape and sound good also. My very rears were shot and the midranged behind the seats sounded like metal trash can lids. I know they ones behind the seats are Kove, I will get you a model tonight and PM you

RyanPerrella

I measured the door speakers and they are 5.25" in diameter. They are Polk, so being aftermarket it looks like they were upsized.

Since posting this I have learned a bit more about speakers after reading here on the web. I think I will definately go with a component system, so 2 way is out. I have a 10 speaker layout, so do i run 2 sets of 5.25 components, that would leave me with 4 crossovers to run throughout the car. Should i replace the crossovers in the door panels with the ones from the new system, seems like a given, I have to remove the pass side door panel anyway to repair a window roller.

I like the idea of the 6.5 "add a woofer" thats an MB quart term, but I want to use more of a sub for the 6.5" holes in the rear quarter panels. Now I am wondering how I power that, if i just use a seperate 2 way amp and mount that under the pass seat. I can run the amp off one of the 3 pre amp rca outs on the head unit so they would have plenty of power. As for power to the 2 sets of components, the head unit is a 50 x4, although they list 20 RMS x 4 which compared with most units I believe is considered a high output radio, this should be plenty to power the components right, I dont want to get a second amp.

Can anyone suggest a small compact 2 way amp to power the 6.5's? something that would fit where the factory ones does? When i fit this do i just not connect the factory amp and bypass it. I think I read its 7 whatts or something. Are there any modern amps that will fit in the pass side cover on the floor?

As for speakers, I like the polk 5.25 components, they include the crossovers and I can use the speaker grills that are currently in the car instead of the awful ones that come with the polk. I was looking at model #DB 5251, any comments, suggestions. These are on ebay for about $120 shipped, if i could get the pair of them for $220 I think i will go that route. That leaves $80 for the 6.5's

For the 6.5's I was looking at a woofer and there are hardly any in a 6.5" Seems they are all 8" 10" 12" or 15" which are i guess primarely for sub enclosures. Since I have the 6.5 holes that are somewhat enclosed already I think the pair of woofers there would be the way to go for bass. I am looking at Kicker model SSMB6. These are available online for $70 for the pair shipped, So i am right at my $300 budged for speakers, although I will no doubt spend more for the amp and the other wiring. These would be powered by one of the pre amp outputs via a2 way amp. (how am i doing, is this all making sense?) Is there any problem going with brand mis-matching with the 4x 5.25, 4x 1" and different 6.5's?

Some other notes, I have found that the 6.5's had already in the past been taken out, so i dont need to worry about cutting up the OE speaker housing, i can just reuse the factory grill covers.

I would love to hear opinions on the 2 types of speakers i have thuse far picked out?

As for current questions, Do i just rewire the hole speaker layout. This really isnt an issue anymore, its pretty simple I think. Now do i just use the basic 2 wire speaker wire. It looks exactly the same as the stuff i have for the home speaker system. What else do I need wiring wise? What gauge wire should i use, I know bigger is best but i dont want to add 50lbs of wiring, so do i go with 16 or 18 gauge? The amp to run the 6.5's will just be run through an RCA cable from the radio to the amp, thats simple enough right? Then from more of the same speaker wire from the amp to the speakers themselves. Do I go larger gauge for the higher powered subs? (am i correct in refering to these as subs, this is where most of my bass is coming from right?)

All the above speakers are 4 ohm, is there any reason I would want to go with a 2 ohm components, infinity has some, are the 2 ohm for lower power amps, or a lower power head unit? I am going to be fine with the 5.25" components running directly from the head unit at 20 RMS right? Or should i consider a 2 ohm component set?

If anyone can answer some of the above questions, that would be appreciated. I am sure I will have more as we go but looking at the first post i can see i already have a much better idea of the route to go and know a bit more about what i am doing here.

Suggestions are still greatly appreciated

a4sfed928

Metal Oxide Semiconductor Field Effect Transistor.

RyanPerrella

yeah thanks i googled that but what does that mean ? is mosfet 50W x 4 my peak power ?

Alan

You wil not be able to fit true subwoofers in the 6.5" space without cutting - they have big voicecoil magnets. You still need real woofers anyway - you don't want to have just midrange drivers & sub-woofers - you will likely be missing lots of mid-bass. if you don't want to cut and you don't want an exrta sub-box - you probably need to forget the sub-woofers and just get good woofers in the 6.5" B-pillar space.

You shoul drive the door component set from the head units front channels with the new passive crossovers placed in the doors. You can use the factory wiring from the amp location to do this - splice wires from there to the new head unit. Drive the rear quarter-panel top and the tweeters on the B-pillar as another component set (similar to the doors) with the new passive crossovers hidden somewhere. Factory had a crossover on the back of the 6.5" (though not connected to it). You may be able to squeeze a small passive X-over in there behind the panel... seen it done. You can connect this also where the old amp was & drive from the head units rear channel outputs. Again splice wiring from here back to the head unit.

Then you need a small 2 channel amp to drive the woofers - you can drive these from the front channel (or a mix of both front & rear) but you will need an active crossover - so an amp with one built in is great. This filters out the highs (and subs?) so you just feed mid-bass signals to the amp & the woofers... You can mount this where the old amp was and connect to the wiring there - the feed will need to come from the head unti so hopefully you have dual front pre-amp outputs to use for this. If not you will need a speaker level to line level converter to feed the amp signals from the front speaker outputs (not ideal - for noise).

MOSTFET is just the type of output stage on the amplifier - its a low power consumption type - that pretty much all head unit amps use. Doesn't really matter.

The amp wiring will need to include the trigger signal from the head - but otherwise can connect to the power & ground from the prev Stock amp.

Alan

dr bob

Ryan--

You'll have a challenge fitting anything where the B-pillar 6.5+ speakers live now. As Alan points out, there's not a lot of room for a voice coli and magnet structure in there. Be aware also that the wiring fro the two elements on the rear quarters runs through the panel at that point, and there's a passive crossover there to protect the tweeter.

For the 6.5, I used a Dremel to remove the old speaker, and put Infinity replacements in there. It's hardly a good enclosure, and the sound is less than precise because of that, among other things.


I'm amused that 6.5's are sometimes referred to as "subs" or "subwoofers", yet the usable frequency range is well into the audible range. Common fault with speaker designations I guess. By their frequency rating they are midranges in fact. A true sub runs out of response somewhere just north of about 25Hz, so it's unlikely that there will be many true subs smaller than 10-12", and even that is real optimism on the manufacturers' part. Most 8" elements classify as mid-bass drivers at best, in my experience. No room under the pass seat for an amp either.

Tampa 928s

I used a bazzoka sub-tube in the rear hatch area. Brought the car alive my speakers are the originals and a new head unit

RyanPerrella

Thanks for the input.

So if the 6.5" dosent give me the bass, then i guess i can get rid of the useless and very heavy spare and put a single large sub in there. I guess i will need a place to mount an amp anyway so I may have to just get rid of spare and keep it in the garage.

So if i do build a sub enclosure in the spare tire location, what do i put in the 6.5" hole. (currently the car has a pair of 6.5" polk mm6510 drivers in it) Do i just put in a matching 6.5" mid in there. What do i run it off of, that would then give me 6 channels, or does the cross over i am using for the rear 5.25 and tweeter also allow me to wire the 6.5" to it as well, so I would then be running 3 speakers off the rear channels? Does that work? Would i still be able to run all 3 off one channel from the stereo, or do i now need another amp to run the rear channel's?

The radio has 3 pre amp outputs, Alan you said it should have 2, i know i need one for the amp for the sub (wherever that goes, wether in the b pillar or the spare tire) what else would i wire with the other pre amp, the front and rear components would run off the head unit itself correct?

And if i go with a sub enclosure in the spare tire well, i then just use a single channel amp correct?

RyanPerrella

And what about ohm's

i see 2 with the infinity refrence series, and 4 with the polk speakers i am looking at? What should i get, whats the real difference to the human ear and to wiring it?

RyanPerrella

Bob,

The 6.5" Kicker woofers I am looking at have a range from 30-500HZ

I am looking at 10" woofers and they seem to start in the 30-40HZ range and go to 250-500HZ range.

Isnt that enough to get bass? Ive read some reviews that with an amp the 6.5's will give me all the bass i need. I dont play rap music and i dont need my car to vibrate, i just want to hear the ENTIRE song when i am listening to something, i dont want to be missing parts. Also the Kickers are shallower then the polks that i pulled out, so i am sure they will fit.