RX7 Convertible Headrest Speaker Replacement
 

RX7 Convertible Headrest Speaker Replacement: I Did It My Way

By jackhild59

This is my method of Headrest Speaker replacement. You have to remove the cover. Retrieve the zipper pull from one side of the headrest and unzip it.

When you get the cover partly pulled back, you must cut the hog rings that hold the front cover in place. You will need some quality side-cutting pliers to cut the hog rings. Now, using lots of hand strength, you must pull the cover up and over the sides. If the leather is tough and brittle, it may tear. If it feels hard, soften it with repeated applications of leather treatment. I find the very best treatment is Leatherique.
www.leatherique.com

Now remove the entire cover.

Split the headrest foam along the seam. One of mine came loose easily, the other I had to cut with a long sharp knife.




Remove the speaker boxes, take them apart and remove the speaker wires from
the boxes.

Discard the boxes, the speakers and the screws. You don't need them anymore.

Replace the headrest foam on the headrest metal and glue it back together with Contact Cement. The wrong glue will melt the foam; other glues will not stick. Be careful to thread the wires up and out the front of the speaker cavities before gluing. Cut one side of the black foam that covers over the speaker faceplate so you can fold it back for access.

After the glue has dried, wire each replacement speaker, keeping a record of the polarity. The polarity must be maintained not only within each headrest, but from headrest to headrest or your sound will suffer. I used 3-1/2” Blaupunkt coaxials.

Press the speaker into the cavity until the magnet adheres to the steel frame of the headrest. The magnet will hold it nicely in place along with the cradle of the foam. It won’t move or rattle.


From this: >>>>>>>>>>>To this:

Don’t be worried that the speaker is not in a box or an enclosure. Most automobile speakers (subwoofers excluded) are designed as ‘Infinite Baffle’ type speakers. That means that they do not need a box to control the speaker excursion. The only thing that is critical is for the sound from the front to be divided from the sound produced by the back of the cone. This mounting method substantially accomplishes this necessity, because the front of the cone will be sealed and pressed against the black foam and then the leather front of the cover.

If you want to be totally sure, you could use some scrap foam or weatherstripping foam to close off any gaps around the speaker basket. It shouldn’t make a difference in these frequency ranges.



Carefully position the foam around the speaker and place the black speaker face foam over the front of your new speaker.

Replace the leather cover; reattach the hog rings as they originally were located. Finish by pulling the bottom of the cover together and zip up the zipper, tucking
the zipper pull in at the end of the zipper run.

Plug in the connector, replace the headrest and enjoy!

The above methodology is exactly that used by the Miata crowd. There are several speaker suppliers that produce speakers specifically for the Miata headrest. None of them will endorse using their speaker in the RX7 Headrest, but they will all work. There is a lot of discussion and disagreement within the Miata community about which speaker is best or if it better to use a standard coaxial 3-1/2” speaker. I used 3-1/2” Blaupunkt coaxial because of the high-efficiency and excellent sound of the speaker. That and all of the other speakers in my car are Blaupunkt.

One issue with non-stock head units: If you use a pair of 4 ohm speakers as described above and you wire the headrest speakers to use the rear channel of the aftermarket head unit, you will present the head unit with a 2 ohm load. Most head units cannot withstand this and may distort, overheat and fail. One solution is to wire the headrest speakers in parallel. This will present the head unit with an 8 ohm load. Nothing will fail, but the sound volume will be quite low and you won’t be able to hear them over the wind. The best solution is to use an external amp that has 4 channels or use one can handle the 2 ohm load. You don’t need a lot of power. This is seems like overkill, but it is the best solution. The stock system in the RX7 is designed for a 4 ohm speaker and thus you avoid the problem altogether.

jackhild59
Member RX7Club.com

excellent piece of work :icon_tup: ... I hope I can find this thread if my headrests blow

awesome write up, I for one definitely appreciate it because I have to do this asap,

Jack,

You are one of those guys who rarely gets the acclaim he deserves for the shared wealth of information you provide to the rest of us. Not that you ask for it, but you certainly deserve it.

Another great post and I am calling for an archive!

Very nice write up! How does it sound compared to stock?

Archive!

http://www.3rdstrategy.com/RX7.htm this is the set of headrest speakers i used they are exact fitment and are designed for our head rests. i like the way you did yhis though. especially if you want a liyyle more bump bump

The sound is better in every way. My OEM headrest speakers were in perfect condition. They worked just as intended.

For a comparison, I replaced the driver side headrest speakers first, then listened from both seats. I listened in both seats stationary and at speed.

The new coax speakers are an improvement in every way. The highs are better, sibilants are now clear, rather that muted. Cymbals, voice nuances etc. are much clearer without harshness. Midrange is strong and open, deep male voices no longer cause distortion at higher volumes. I listen to lots of sports talk on both AM and FM-the difference is amazing at speed.

There is no bass, nor did Mazda intend for there to be bass. In the OEM system, the low frequencies are always routed to the rear subs and the front speakers, no matter the fader setting. (This 'virtual subwoofer' works pretty nicely at lower volume settings.)

One very important issue is the efficiency of the new speakers. They are rated at 96db/w @ 1m. This is important because now the speakers play louder at a given setting of the volume. The original amplifiers are not very powerful and are not very clean. At higher volumes, it's hard to tell if the amplifier is distorting or the speaker is distorting. Now, I seldom have that issue. When I get distortion, it is the amp NOT the speaker. I guess the best description is that the sound from the headrest sounds open and 'effortless' and musical, where before it often sounded strained and harsh.

Nice writeup Jack! Thanks! I'm about to do this myself.
One tech note: in your section in RED a few posts down you said wiring the 4ohm speakers in parallel will present the amp with an 8 ohm load. I'm sure you actually meant to say wiring them in SERIES will present the amp with a 8ohm load. Minor correction, but important! (parallel will divide the impedence, series will add the impedence).

Thanks for catching that, I edited that for clarity and OBVIOUSLY fat-fingered it.

To clarify: If you wire the speakers in PARALLEL, the 4 ohm speakers will present a 2 ohm load to the rear channel of your aftermarket head unit. I do not recommend this. You may solve this problem by wiring the headrest speakers in SERIES, therefore presenting an 8 ohm load to the rear channels. This is safe, but may limit the volume to an unacceptably low level.

Yeah, I know about these. Nice install example on the web site, huh? Real quality stuff-headrests stuck together with electrical tape?:rolleyes: Shouldn't your public presentation of your product reflect be the very best it can be???

Seriously, they may sound ok and be high quality speakers, but all the limitations that are inherent to the OEM design are still issues with these speakers-very small cone area, low efficiency, no coaxial design. I mean, come on, when you see the side by side pictures comparing the OEM to the M-II on the web page, are you really that impressed?

There are a couple of other speakers that fit and are spec-ed for our OEM housings. They have been around for a while. There is lots of good information is on the Miata boards. Over the years those guys have just not been happy with anything that fits the OEM housings.

The Clearwater Company (http://www.clearwateraudio.com/Clear...dio/CWC3D.html) has been pretty much the standard for Miata guys. Most of their discussion is whether or not the speaker in question sounds as good as or better than the Clearwater. I couldn't get Clearwater to recommend thier product for my headrests. The best they would do is offer me a generous return and refund if it didn't work out.

I must add that the Clearwater speakers at $95 for both headrests is a very good deal.

the pdf still has it as wired parallel is 8 ohms. may wanna get a mod to edit your post and upload a new pdf to reflect that.

Nice work. If I hadn't yanked the stock seats out of my vert I'd have done this.