Many have replaced their stock headrest speakers with aftermarket 4ohm speakers. Looking at the Fiero manual wiring diagram, the headrest speakers are clearly wired in parallel. This will create a very low 2ohm load using 4ohm aftermarket speakers (stock were 10ohm creating a 5ohm load) and could eventually damage your factory deck's amplifier.

Some Mazda Miata's had their headrest speaker wired in parallel too and Clearwater Audio had speakers for this application. I replaced the seat speakers in my 84 project car with a set of Clearwater Audio Miata headrest speakers. Part number CWC-3F - email about these. http://www.clearwateraudio....ter_Audio/CWC3D.html

They created a new part number CWC-3F (F for Fiero) and added the correct connectors so it's just a plug and play installation (once you get the seat apart). They are 3-1/2" 2-way speakers with the correct power rating for a stock deck and 7-8 ohms each. These will work with the stock wiring with no changes other than an inline bass cap (optional) and it won't overload the amplifier with a 4ohm load. For anyone who's never had their seats apart, here's how to do it. http://www.mrmikes.com/fierospeakers.htm

I've installed the Clearwater Audio speakers this weekend, and here's what you can expect.

What you get in the box - 4 high quality speakers, well packed.


The speakers already have a pigtail with the correct connector to plug into the existing harness in the seat.


The connector makes installing the speaker a simple "plug 'n play". I checked, and the polarity is correct.


Here's how the Clearwater Audio speakers compare to the stock Delco headrest speakers.


Here they are pressed into the foam of the headrests. It works, but GM could have found a better way to install these.


HOW DOES IT SOUND?
I have installed 470mfd capacitors (bass blockers) in the +wires for the headrest speakers as they comes out of the deck. This will cutoff all frequencies below 90Hz (approx.) which eliminates the bass which can't be reproduced by a 3.5" speaker very well anyway. My subwoofer setup gets its signal off the front channels, so switching the fader completely to REAR only, eliminates the front speakers and all subwoofer output.

Playing the headrest speakers only, with a cutoff at 90Hz (with the bass blockers) produce little bass, because you are only playing midrange and higher. The speakers reproduce this very clearly and can produce quite a bit of volume without distortion. The limit seems to be the signal quality coming out of your deck.

By nudging the fader toward the front very slightly, I got the subwoofer to come in and a very low volume from the front speakers. In fact I had to lean up to the dash to hear them. At this setting I was basically listening to the headrest speakers and bass/mid-bass from the subwoofer. This immediately "fills out" the sound immeasurably - and oddly enough, it "sounds" like the mid-bass is coming from the headrest speakers!

With the fader set "dead center" I found that the front/rear balance is exactly correct. I listened to all kinds of music for almost an hour, including Big Band, drum solos, country, heavy metal, and rock and roll. The front sound stage is full and complete, and you at first think the headrest speakers aren't working at all, but as soon as your turn your head slightly, you'll hear that speaker right away. While looking straight ahead (as you normally would) the overall effect is excellent.

Bottom line, I'm very happy with the results and would recommend these. They fit easily because they are the same 3.5" diameter as the stock ones, and they are 7-8ohm speakers, and won't produce a too low impedance that could damage your deck's amplifier.

Complete system in car: https://www.fiero.nl/forum/Forum2/HTML/081643.html

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3.4L S/C 87 GT www.fierosound.com
2002/2003/2004 World of Wheels Winner &
Multiple IASCA Stereo Award Winner

[This message has been edited by fierosound (edited 08-31-2008).]

^^^

Great info. I may have to pick up a pair. Actually make that 40 pairs to do all the cars. thanks for the link.

For us non-audio people, can you give us a few more details and maybe a picture of the "330mfd capacitors (bass blockers)"?

quote Originally posted by tampalinc: For us non-audio people, can you give us a few more details and maybe a picture of the "330mfd capacitors (bass blockers)"?

There's more infomation in the LINKs at the end of the first message for those who wanted to read up. BUT, I will repeat some here...........................


When you have a subwoofer in your system, you usually want to decrease the amount of bass going to your mid-range speakers (tweeter will already be crossed-over). This will get you better mid-range and higher sound and increase the power handling by rolling off the bass before it gets to your mid-range speakers.

To do this, you can use a "bass blocker" (high pass filter) a capacitor placed in series with the speaker input. It blocks the lower frequencies, and allows the higher frequencies to pass through. Bass blockers are installed in series, one end connected with the positive lead from your amplifier and the other end connected to the positive lead of each of your speakers. Bass blocker capacitors are available at any Radio Shack, eBay, Crutchfield or parts supply house. You could also use an electronic crossover to filter the signal.



I used capacitors inline before the 2-way crossovers to the front speakers which block frequencies below 175Hz (may change this later). This seems to be a good crossover point for the Infinity component set with the subwoofer. For the headrest speakers, I used caps which block frequencies below 120Hz. I installed these inline behind the radio rather than at the harness connecting to the seats.

Values for 50 Volt non-polarized Bass Capacitors for 2/4/8 ohm speakers.

[This message has been edited by fierosound (edited 04-03-2007).]

Excellent find.
Excellent write-up
Thanks!

^^^

Anyone else try a set of these yet?

I was going to try them, but I found 2 pairs of 3.5" Sony Xplods on ebay so I took that route instead, figured I should just do the whole system Sony since all my speakers were shot and I had already bought the 4" X 10" Xplods for my new dash.

quote Originally posted by Cowabunga_kid: I was going to try them, but I found 2 pairs of 3.5" Sony Xplods on ebay so I took that route instead, .

I went with these Clearwater speakers because the headrest speakers are wired in parallel and using pairs of 4 ohm speakers will create a 2 ohm load on each channel of your amplifier. That's OK if your amp can take it. I'm using a Delco CD unit. https://www.fiero.nl/forum/Forum2/HTML/079932.html

[This message has been edited by fierosound (edited 06-07-2007).]

Yeah, if I had the stock headunit I wouldnt use the after-market either, its just my whole system was garbage including the headunit, along with many other things in this money sucking device they call a fiero lol. My headunit wasnt even stock with the car and someone wired it to the ignition, I havent come across that nightmare yet, the sound system is going in last and hopefully it will work well. (Keeping fingers crossed)

But now you raise questions to mind, would the after-market headunit be able to handle the extra 2 ohm load, without a seperate amp?

quote Originally posted by Cowabunga_kid: But now you raise questions to mind, would the after-market headunit be able to handle the extra 2 ohm load, without a seperate amp?

Probably not. You'll have to check your head unit's specs.

In the above thread, musicman_L7 mentioned that the Pioneer deck in his brother-in-law's GT kept tripping into "cut-out" or amp protection mode past a certain volume level. They changed to high impedance speakers to solve the problem.

I haven't ever tried this, but it seems you can wire a 2ohm resistor (big white ceramic rectangular one) inline on the positive lead at the radio. This will cut the volume a bit but also create a 4ohm load. http://www.ls1tech.com/foru...ex.php/t-396064.html

More on this system here: https://www.fiero.nl/forum/F...2/HTML/081643-2.html

quote Originally posted by fierosound: Probably not. You'll have to check your head unit's specs.

Thanx for the all the help. Im not the best when it comes to the whole sound system thing, but srry if this took the whole point of your thread a little off topic.