Millennium-5 Frequently Asked Questions
General specifications, what they mean, and how to
compare to other speakers
What is the power handling
capability of the Millennium-5's?
I've seen speaker brand 'X' claim to handle
30, 50, 100, 200, 1000+ watts. Why are the Millennium-5 speakers only rated
for 20 watts?
How much power do I need?
I saw another seller claim that because their speakers had
bigger magnets, they were louder. Is that true?
OK, then what determines how loud the music will be coming
out of my speakers?
I have an amplifier rated at more than
20 watts. Is it safe
to connect to the Millennium-5's?
My old factory speakers were 4 ohms and the Millennium-5's
are 8 ohms. Is this OK?
I saw another seller claim that
crossover capacitors aren't
required for their speakers. What's the truth?
What is the frequency response of the Millennium-5 speakers?
I've seen other manufacturers claim a frequency response of
20-20,000 Hz for their speakers. Isn't that better?
Will the Millennium-5's sound as good as the original
I've heard some users talk
about the M5's as being good for 'Augmented Wideband'. What's that?
I've seen other speakers for the Miata advertised on eBay
and some other sites. What about them?
One speaker I saw said that it was 'low profile' to be more
comfortable in the seat. Is that true?
I read somewhere that a 3.5" speaker would perform better
than the factory shaped oval speakers. Is that true?
Are the Millennium-5's 2-way speakers?
Aren't 2-way or 3-way speakers better?
What about crossover? Do I need them?
Are there any general use guidelines for using the
Will the Millennium-5 speakers fit into my Miata without
Are there any of the 90-97 Miata's that the speakers don't
fit into as a replacement?
Do you have the speakers for the Miata's with the 3.5�
Which Miata's came with headrest speakers installed?
How do I open up the headrests to see what I've got?
Can I reuse the wiring and boxes with the Millennium-5
Questions about retrofitting the Millennium-5 speakers into a Miata
without existing headrest speaker boxes
OK, I've opened up the headrests and there's nothing there
except two empty cavities. Now what?
I opened up the headrests and found some crappy loose
speakers just stuffed in there!
OK, I don't have any old speakers or boxes. How do I install
Why do I need the boxes? Why can't I just put the
Millennium-5 or any other small speaker in there?
I need boxes for the speakers. Do you sell them?
What about wiring and a car radio plug adapter?
How should the headrest be wired in the Miata?
Q: What is the power handling capability of the
A: With the installed crossovers they are rated to handle
20 RMS watts each. As part of our development testing we subjected the M5's
to 5 watts of white
noise for 8 continuous hours and 10 watts of white noise for 10 continuous
minutes without issue. White noise is audio 'snow' similar to what you'd hear when you
have an FM radio between stations. This is a painful level of audio output
that you would never want to have 4 inches from your ears but it does show
that the M5's can handle a lot of power.
Q: I've seen speaker brand 'X' claim to handle 20,
50, 100, 200, 1000+ watts. Why are the Millennium-5 speakers only rated for
A: The Millennium-5's are rated for 20 watts because
that's the actual honest number (and it's plenty - see the next question).
Be careful when evaluating power handling numbers from other manufacturers
as they are often being deceptive in reporting this number. It's also easy
to confuse power ratings with volume - they are related but are very
Power Handling Capability is actually the level of
continuous amplifier power over the normal frequency range of human hearing
with which a speaker will continue to operate in a normal manner. Normal
means operation without electrical or mechanical failure, and without any
significant distortion or audible side effects.
handling capability of a speaker system is made up of quite a few elements:
- Voice Coil: The voice coil (a winding of fine copper wire attached to
the back of the speaker cone down inside the magnet structure - see picture
on right) must be able to sustain the power running through it. The voice
coil is basically a simple coil of wire like an electric heater that's wound
around a form which is then attached to the back of the speaker cone. Just
like a heater it gives off heat as more power is passed through it. Too much
power and the wire just burns out. So the more robust the voice coil
structure the more capable a speaker is to have amplifier power delivered to
it. However, in manufacturing high fidelity speakers you want the speaker
structure to be as light as possible in order to move quickly (called
transient response) so you don't want to install a larger voice coil in a
speaker than needed.
- Speaker Suspension and Surround: The surround
structure is the part of a speaker that attaches the cone to the metal
basket. In the Millennium-5's, we use a special butyl rubber material for
the surround that runs around the edges of the speaker. Other manufacturer's
use foam and the cheapest speakers just press the edge of the cone into an
accordion shape so it can flex (original Miata speakers). There is also a
part of the speaker that holds the rear of the cone in place called the
spider (right). The purpose of the surround and spider is to hold the
cone in place and lets it move back and forth like a piston. To produce more
volume a speaker needs to push more air - it's as simple as that. The
surround material and structure determines how far the cone can move back
and forth to produce sound waves As you would expect, there are practical
limits as to how far the cone can be moved without tearing the surround or
- Magnet Structure: The magnet structure is
what enables the speaker cone to move and create sound. When an electric
current flows through a wire (in this case, the voice coil), it sets up a
magnetic field around that wire, and for a coiled wire that field is
increased. If the coil of wire is placed in the field of a magnet, the field
of the coil interacts with the field of the magnet and force is applied to
the coil. As you probably remember from elementary school science, two
magnets with like poles push away. So in a speaker system, the amplifier
creates alternating current energy which when fed to a speaker, causes the
magnet field around the voice coil to build up and collapse as the energy
changes. This in turn moves the cone which moves air, thereby creating
sound. A larger magnet structure can work with more amplifier power to move
a heavier cone or move a cone further, but the magnet doesn't want to be any
larger than is necessary as it can over dampen the cone. This is why simply
having a large magnet isn't necessarily a good thing. A speaker with too
large a magnet will actually have poorer frequency response and just sound
lousy.So to determine a power handling capability rating, a
manufacturer should run a maximum level of power through their speaker for a
continuous period of time, over all the intended operating frequencies, and
without distortion or undesirable audible side effects.
- Enclosure: A proper enclosure is critical to getting
good sound from a speaker system. The enclosure serves to dampen the cone
at certain frequencies and when properly designed and matched to the
speaker, provides a smooth frequency response and greatly increased power
handling capability. This is why simply stuffing loose speakers into the
headrests will never produce good audio. The Millennium-5's were
specifically designed for the speaker boxes that mount into the Miata
unscrupulous vendors report their power handling number as a 'peak' or
instantaneous number that the speakers can handle without suffering damage.
This peak may only be for 1/1000th of a second. Since speakers obviously
play music longer than that, a peak number is pretty meaningless.
other cases, the reported power capacity may be a combination of a peak
rating and also only at a particular frequency � say 1,000Hz. It's easier
for a speaker to reproduce sounds and handle power at certain frequencies.
But to report power handling for only one frequency isn't realistic or
Q: How much power do I need? Is 20 watts enough?
A: It's plenty!
20 watts of continuous music with the Millennium-5's in the Miata headrests
is LOUD. Remember, these speakers don't reproduce low bass frequencies
(that's up to your door sepakers) and are going to be located only a few inches
from your head. We actually caution customers to be careful as you don�t
want to risk any hearing damage.top
Q: I saw another seller
claim that because their speakers had bigger magnets, they were louder. Is
A: No, that's false. The size of the magnet has nothing to
do with the loudness of the speaker. Sound volume is determined by the
amount of power deliverable by the amplifier and the efficiency of the
speaker/enclosure design. Saying that a bigger magnet makes a speaker louder
is like saying more chrome on a car makes it go faster - it's just nonsense
some unscrupulous sellers spout to try and deceive buyers.
of the magnet structure is critical to the performance of the speaker and
you don't want it too large or too small. The magnet structure works with
the voice coil and suspension to regulate the movement of the cone. The
magnet structure should be designed specifically to deliver the performance
required for the speaker system including the enclosure. The Millennium-5
magnet structure is a lot larger than the original speakers in the Miata,
but only to the extent required to meet the design and performance goals of
the speaker. top
Q: OK, then what determines how loud the
music will be coming out of my speakers?
A: That's actually the key
question of any speaker system. You want the volume at the level you'd like
to listen and you'd like smooth frequency response and no distortion at all
volume levels up to the loudest you'd like to listen at. So there are two
interrelated goals for any speaker system: efficiency and frequency
response. You want a speaker that is highly efficient and has a wide
Efficiency means how effective a speaker system
is at turning amplifier power into volume and is rated in decibels, or dB.
Decibels is a scale and not an absolute value. Every 3 dB represents a
doubling (or halving) of the apparent sound level. So if you have two
speakers and one is 3dB more efficient than the other, the more efficient
speaker will be about twice as loud given the same amplifier volume setting.
Wide frequency response means that the speaker can reproduce sound
at all frequencies across it's range with similar volume levels (click
for more on frequency response)
In the Millennium-5's we used a
number of manufacturing techniques to get the best possible frequency
response and efficiency. It's difficult to create such a small speaker that
does both and that's why there have never been good quality replacements for
the Miata headrests before the Millennium-5's.
To achieve a wide,
low distortion frequency response in the Millennium-5's, we made use of a
butyl rubber surround and polymer impregnated cone. The surround lets the
cone move much more freely than a foam or paper surround - this allows the
speaker to have a much more extended low end frequency response. The polymer
in the cones helps minimize distortion by keeping the cone from flexing
while in use. Flexing is a normal artifact of speaker operation and
different cone materials are better than others at minimizing this effect.
There are tradeoffs with all cone materials and in our testing the polymer
impregnated cone gave the best combination of performance and cost in the
Miata. The magnet structure is also important. We used a larger magnet and a
deeper channel for the voice coil to provide longer cone extension
capability. The larger magnet structure also helps control the looser
suspension created by the butyl surround. When installed in the headrest
speaker boxes, the result is a nice warm and extended frequency response.
Our speakers have a relatively high efficiency when installed in the
Miata headrest boxes. Without getting too technical, there is a correlation
between efficiency and low-end frequency response. We specifically designed
the mass of the cone structure and the compliance to best work with the
headrest boxes in the Miata. Most users should find any quality radio
perfectly capable of driving the Millennium-5's as loudly as they'd like. As
a matter of course we do recommend more power for the Millennium-5's if you
can practically afford it as long as the power is cleanly delivered. Running
an amplifier into clipping (distortion) is the sure way to destroy any
speaker.topQ: I have an external amplifier rated at more
than 20 watts. Is it safe to connect to the Millennium-5's?
in fact it's actually safer. Generally, what destroys speakers isn't clean
audio but rather the distortion that is generated when an amplifier is
driven beyond its rated power. Any amplifier can put out more power than
it's rating, but that excess power is distorted and the sound waveforms are
what are called clipped
. Clipping is really bad for speakers and can
damage the speaker's cone or burn out the voice coil. Clean power is much
safer for speakers.
Still, some protection for the speakers is a good
idea so we include crossover / blocking capacitors pre-installed on each
speaker. The correct value capacitor will start to gently roll off response
below the point that it is safe for the speaker to reproduce. Blocking
frequencies below what a speaker is designed to handle will help protect it
from being overdriven and potentially damaged.
The correct value for
any speaker depends on a number of electrical, design, and performance
characteristics for the driver and must be carefully calculated. Use of the
wrong value will either make the speaker sound weak and tinny or provide no
protection at all. For the Millennium-5�s, the correct crossover capacitor
is a 150uf non-polarized capacitor rated at 25 volts or higher. These are
included and already installed with all Millennium-5's. If you ever need to replace the capacitors
on your M5's, we have these capacitors available on our
.topQ: My old factory
speakers were 4 ohms and the Millennium-5's are 8 ohms. Is this OK?
A: Yes, it's no problem. We intentionally designed the Millennium-5 speakers
as 8 ohms to provide a greater safety margin with the wide range of
aftermarket radios that are now out there. The amplifier in any car radio
can have difficulty operating with impedances that are too low. With 4 ohm
headrest speakers, the two seats connected in parallel (the factory
configuration and what we recommend sticking with) will present the amp with
a 2 ohm load and potentially lower than 2 ohms under certain operating
conditions. This may cause some amplifiers trouble as they sense they are
close to operating into a short circuit - zero ohms. This may cause the
amplifier in your radio to go into 'Protect' mode - momentarily shutting
down to protect against damage.
The Millennium-5's are 8 ohm speakers
so wired in parallel present a 4 ohm load to the amplifier in the radio. Any
car stereo will have no trouble with this and will operate normally.
What's the tradeoff? With a lower impendance speaker, more power will be
drawn from the amp which means you can potentially get greater volume.
However, because these are headrest speakers and located only inches from
your ears, power needs (and ultimate volume levels) aren't a factor, so we
chose to design the speakers to be 'foolproof' with whatever stereo or
headunit/amp you may have in your Miata.top
Q: I saw another
seller claim that blocking capacitors aren't required for their speakers.
What's the truth?
A: 'Blocking' or crossover capacitors aren't
required for any
speaker, but with small speakers like those in the Miata
headrests a properly sized capacitor connected to the '+' lead of the
speaker will help protect the speaker from being overdriven and allow
maximum performance. To understand why, we need to explain how speakers
What we can hear is energy that vibrates the air back
and forth. Each back and forth vibrations is called a cycle. The number of
cycles per second (or Hertz) is called the frequency. To recreate sound, a
speaker cone moves back and forth vibrating the air just like the original
sound. Low frequency sounds contain a lot of energy. If you've ever heard an
organ in a cathedral or sat near a a bass drum, you know that you can not
only hear the sounds but feel them! The challenge with speakers is that to
recreate low-frequency sounds (from around 20 to 200 Hz) at the same level
as mid and high frequency sounds, a lot of air must be moved to duplicate
the energy of the original sound. Speakers accomplish this by moving the
cone further in and out. This presents the problem with small speakers.
Simple physics dictates that there is a limit to how far a cone can move
in and out. If you exceed that distance you will damage the cone and/or
speaker suspension. A crossover (in this case a capacitor) prevents very low
frequency energy from reaching the speaker and potentially damaging it. This
is why all multiple driver speaker systems have crossovers.
Millennium-5's were specifically designed with a suspension that permits
greater cone movement than in the oem speakers (or the cheap transistor
radio speakers other sell). This gives the Millennium-5's their warm,
pleasant sound and extended frequency response (see next question). However,
there is a practical limit of cone motion for even the Millennium-5's.
We recognized that not everyone was comfortable with attaching crossover
capacitors, so we designed the terminal mounting arrangements on the
Millennium-5 to better accommodate the recommended crossover capacitor. The
design lets us pre-attach them on all Millennium-5 speakers as part of
the manufacturing process. This means that all buyers get the benefit of the
proper crossover but we maintain the simple, drop-in installation. The best
part for buyers is that because of the efficient design, we are able to
include the crossover capacitors at no additional cost.
What is the frequency response of the Millennium-5 speakers?
Millenium-5's have a frequency response of 100-14,000 Hz -3dB measured with
1 watt of power at .5 meter distance. This is a range that will effectively
cover the human voice and most musical instruments. This is the critical
range of frequencies for creating a realistic stereo image. The
Millennium-5's (and any other small speaker this size) are not designed to
cover very low bass frequencies such as from bass guitars, drums, etc. This
is just a matter of physics - any small cone can't move enough air to
reproduce very low frequency sound.
You should rely on your door
speakers (or an installed subwoofer) for very low frequencies and blend the
sound with your radio's fader control or a crossover into your headrest
speakers. Check out our M800
door speakers.topQ: I've seen other manufacturers claim a
frequency response of 20-20,000 Hz for their speakers. Is that better?
A: No, it doesn't mean anything. Unless a speaker has a frequency response
published along with the parameters of the measurement including the plus or
minus 'X' dB
points indicating rolloff points, it's a meaningless claim of performance.
The range of human
hearing is approximately 20 to 20,000 Hz - at least when you're about 15
years old! The upper limit of hearing starts declining soon after that point
:( All speakers reproduce some sound at all these frequencies. What's
important from a listener's perspective is the ability of a speaker to
produce uniform output across its intended operating range. In other words,
you would want a sound at 40Hz to be just as loud at a sound at 400, 4000,
and 13,000 Hz. This is what is called a flat frequency response.
Look for the manufacturer's frequency response curves for their
speakers. What you�re looking for when examining one of these is a
relatively flat graph � it will never be ruler flat, but there will be a
pronounced roll-off at both the low end and the high end. The actual
frequency response will be the flat portion between the lower and upper
ends. The -3dB point is commonly used to denote the effective limit of the
response as it indicates an approximate halving of the loudness. If you want
to look at the response curve for the Millennium-5's, it's available at
and is included with every Millennium-5 set
of speakers purchased.top
Q: Will the Millennium-5's sound as
good as the original speakers?
A: They will sound better! The
original speakers weren't very sophisticated or expensive components. They
had simple paper cones, foam and accordion paper surrounds, and tiny little
magnets. They were OK but not great. Here's a comparison picture.
Millennium-5 speakers were specifically designed for the Miata headrest.
There are numerous improvements that we designed into these speakers:
- The magnet is a much larger structure that handles more power. Power
doesn't just mean loudness - it also means the ability of the speaker to
control the cone movement more accurately and thus provide a wider range of
sound and better fidelity.
- The surround is butyl rubber. The surround is the part of the speaker that attaches the cone to the metal
frame. A butyl surround has two benefits. First, it permits a freer motion
of the cone which results in more low end response. No speaker this small is
going to have bone-thumping bass - it's physically impossible - but the
Millennium-5's have a low end that extends down to around 100Hz. That's
about the lower end of the human voice range. This means that speech and vocals
have a nice, neutral, mellow sound that is very pleasant to listen to.
There's no harsh, tinny, or shrill sounds like you get from cheap speakers.
The second benefit of the surround is that it's much more environmentally
resistant to moisture than the oem foam surrounds. This means it will last
much longer than the originals.
- The cones are polymer treated. This is a coating that actually bonds to the paper cones and makes them more
rigid. Making them more rigid is desirable as that permits them to more
faithfully reproduce the sounds sent to them by the amplifier. The coating
also has a secondary benefit of making the speakers stand up better to
moisture in the air. A definite plus in a convertible.
Q: I've heard some users talk about the
M5's as being good for 'Augmented Wideband'. What's that?
A: Augmented Wideband is a term that describes a philosophy which
we at 3MS have always held. Essentially, AW refers to having a low-mid bass
driver that potentially sacrifices some of the lowest frequency handling
capability in exchange for being able to reproduce frequencies up into the
critical midrange frequencies - which is where voice and most instruments
will be heard.
And correspondingly, the typical tweeter found in
traditional systems is replaced by a slightly larger driver that is capable
of operating down into the critical low-midrange frequencies. When crossed
over properly to the mid-bass driver, the result is a very pleasant, warm,
and normal sound as opposed to the
traditional shrill, peaked sound you get with many OEM and aftermarket
The M5's are not tweeters - they are midrange
speakers designed very specifically to operate down to a very low frequency.
In the Miata the real bass is left to the door speakers and the M5's
seamlessly take over and handle all the vocals and most instruments.
Q: I've seen other speakers for the Miata advertised on eBay and some
other sites. What about them?
A: Aside from our own speakers which we
do offer on eBay for customers that like to shop there, there are some other speakers that may fit the headrest
boxes occasionally advertised on eBay and some other locations. You should
note that those are simply paper-coned transistor radio speakers usually
bought in bulk from Asia for about $1 each and not high-fidelity music
speakers. While some of them will fit the Miata, they will frankly
like a transistor radio. The Millennium-5 speakers are the only premium
music speakers designed for the Miata, warranted for a full year, provided with actual
specifications and frequency response data, and sold with a 30-day money
Sadly, those cheap speakers you see elsewhere are
typically sold at the same cost or more than the Millennium-5's and they have no
warranty at all! The sellers typically make all sorts of claims about how
'great' they sound because they know that when someone buys them, they won't
be able to compare them to anything else. While any speaker can make some
noise, $1 transistor radio speakers are not very nice to listen to for
music. Buyer Beware.
topQ: One speaker I saw said that it was 'low
profile' and therefore more comfortable in the seat. Is that true?
Unfortunately, that's just a bunch of nonsense intended to mislead buyers
into thinking there is some advantage to the speakers they are selling. In
the Miata the speakers mount into the oem boxes in the seats. They either
fit or they don't. The Millennium-5 speakers are exact fit replacements for
the oem speakers and therefore there is no effect upon the seat or
upholstery. We are aware of the seller that makes this claim about the low
profile speakers - they are simply cheap transistor radio speakers and not
music speakers. The 'low profile' claim is just a gimmick to try and mislead
buyers. See the previous question and answer for more details on this and
similar scams. topQ: I read somewhere that a 3.5" speaker
would perform better than the factory shaped oval speakers. Is that true?
A: No, that's nonsense. The shape of the speaker has nothing to do with
the sound it produces. The area of the cone (usually measured in square
centimeters and seen on many spec sheets as 'Sd') is the surface area of the
piston moving with the same velocity as the voice coil and producing the
same volume velocity as the radiator at low frequency where all points of
the surface are still in-phase. Or in other words, it's how much area is
being devoted to moving air to reproduce the sounds.
Millennium-5's have an Sd of 29 cm2. A typical 3.5" speaker like the Dayton
ND90-8 sold at Parts Express has a Sd of 31.2. You'll note that they are
almost the same.top
Q: Are the Millennium-5's 2-way speakers?
A: No, they are single cone drivers. top
Q: Aren't 2-way
A: Not necessarily. The idea behind multi-driver
speakers is that each speaker element can reproduce the sounds in that range
which is ideal for its physical and acoustical properties. However in the
Miata, the headrest speakers are intended to cover the important voice and
higher frequency instrument area. A quality single-driver speaker like the
Millennium-5 covers that range completely.
The ideal configuration
for the stereo in your Miata is to have the door speakers reproduce the
low-frequencies like kick drums, bass guitar, and lower organ notes, and then you
blend in the headrest speakers to cover the upper frequencies and produce a
nice left-right stereo field.top
Q: What about crossovers? Do
I need them?
A: While not 100% required, we strongly recommend that
the Miata headrest speakers have crossover / blocking capacitors installed
and the Millennium-5's do.
A crossover is made up of electrical components that allows only
certain frequencies to reach the speakers. This provides two benefits.
First, it permits the speakers to only reproduce the frequencies they are
best at producing at maximum power levels. More importantly, it protects
high frequency speakers from being overdriven and potentially damaged by low
frequency energy. To much low frequency energy into a high frequency speaker
can overdrive it (push the cone beyond it's normal limits of travel) and
damage the suspension. An overdriven speaker may get burnt out and not work
at all or may still work but sound thin and buzzy.
Given the small
size of the speakers in the Miata headrest, we recommend that those speakers
have the proper crossover / blocking capacitors installed. All Millennium-5
speakers include the exactly calculated crossover capacitors preinstalled.
This permits maximum performance and protects your speakers by blocking low
frequencies that might damage them. If you choose not to protect the
Millennium-5 speakers by bypassing the capacitors, limit the amount of bass
that you try to reproduce from the speakers. You should get your bass energy
from your door speakers and perhaps a subwoofer - not from the headrest
speakers. They were not designed to produce very low frequencies.
topQ: Are there any general use guidelines for using the
A: Aside from having them properly wired,
there are several guidelines for ensuring the best sound and long life of
the Millennium-5 speakers. Specifically:1. Adjust your stereo
: while safely driving at a normal speed, turn your
stereo's balance control fully forward so that all sound is coming out of
your door speakers. Adjust your left/right balance until you get a good
stereo coverage. Then slowly adjust your fader to start bringing sound to
the headrest speakers. Continue fading to the headrest speakers until you
are hearing more content from the headrests than the doors. Stop and fade
back slightly to the door speakers so that they are now louder. This is the
optimal point for creating a 3D stereo field and also compensating for wind
noise.2. Do not overdrive the speakers.
If you hear distortion
from the speakers reduce the volume immediately! Even a inexpensive radio
rated at a small power output like 5 watts is capable of putting out many
times that amount of power but severely distorted. This is called
overdriving and can damage the speaker's surrounds, suspension, or burn out
the voice coil. Damaged caused by overdriving the speakers is not covered by
the Millennium-5 limited warranty.3. Do not try and get lots of
bass from the headrest speakers!
Physics can't be changed - a small speaker
like the Miata headrest speakers cannot move the necessary volumes of air to
reproduce very low frequencies. The Millennium-5 speakers are tough and much
more rugged than the oem speakers, but they can be overdriven and damaged.
The most likely damage will be that the suspension is torn and sound becomes
distorted. Damage due to overdriving is not covered by the Millennium-5
limited warranty. All Millennium-5 speakers include
pre-installed crossover capacitors to help to help protect the speakers
while still allowing maximum performance. If you want more bass from your
Miata stereo setup, consider replacing the door speakers - our
's will give
you all the bass you'll want. Of course, you can always add a
subwoofer if you really
want ultimate low
Q: Will the Millennium-5 speakers fit into my Miata without modification?
If you have a 90-97 Miata with the standard headrest speakers, they are a
direct swap. Because they are exact fit replacements, installation consists
of simply unscrewing the 4 screws that hold in the old speakers, removing
the push-on wires, fitting the wires onto the new speakers, and reinstalling
Q: Are there any of the 90-97 Miata's that
the speakers don't fit into as a replacement?
A: There were a
very few Miata's with moveable headrests and our speakers won't work in
those. If you have one of the rare Limited Edition or Special Edition
Miata's, our Retrofit Kit Special Edition
is what you need.
You can check what speaker arrangement you have in your Miata in less
than 10 minutes by following the instructions in our on-line installation
Q: Do you have the speakers for the
Miata's with the 3.5" speakers?
A: We don't manufacture 3.5"
speakers but our Retrofit Kit Special Edition
will give you a complete, screw in solution.
Which Miata's came with headrest speakers
A: Except for special and limited editions, there were
basically four models of the 90-97 Miata. The 'Base', 'A', 'B' and 'C'. The Base
and A models did not come with headrest speakers but they were available as
an option. The B models seemed to mostly have come with the headrest
speakers. If you have power mirrors, you probably have a B model. The 'C'
model is just a 'B' but with a leather interior.
Q: How do
I open up the headrests to see what I've got?
A: It's actually pretty
easy. There's an installed zipper on each seat headrest. Raise the tab of
the zipper and unzip. There is then a foam cover in front of the speakers.
In some Miata it's held with a couple of screws and in some it's just held
into place when the seat zips up. Pull that foam away and there are the
Q: OK, I've opened up the headrest and I've
found the old speakers. They're practically falling apart! Can I reuse the
wiring and boxes with the Millennium-5 speakers?
A: Yes! You should
have a simple 10-minute swap. The boxes are hard plastic and impervious to
moisture and deterioration. Just remove the old speakers, drop in the new
Millennium-5's, put down the top, and go for a ride!
Questions about retrofitting the Millennium-5 speakers into a Miata
without existing headrest speaker boxes
Q: OK, I've opened up the
headrests and there's nothing there except two empty cavities. Now what?
A: That means you have a Miata that didn't come with the headrest
speakers or someone has removed them. Simply order our
Retrofit Kit which
includes the Millennium-5 speakers, our NABX1 speaker boxes, and all
necessary mounting hardware.
Q: Actually, I opened up the
headrests and found some crappy loose speakers just stuffed in there and
some cretin has hacked up the foam in my seat! Is it hopeless?
Don't despair - the situation can be salvaged! Carefully remove the old
speakers making note of how the wires were connected (however, assume
they�re wired incorrectly since anyone willing to hack up a Miata probably
didn't get the wiring correct - wiring is important and it's discussed
below). Even if someone has cut away the foam, the original speaker box
mounting plates will still be embedded in the seat backs. Our
Kit comes with all the required mounting hardware to securely fasten the
boxes into place.
Q: OK, I don't have any old speakers or
boxes. So how do I install the Millennium-5's?
A: You need our
Retrofit Kit which includes the Millennium-5 speakers, our NABX1 speaker
boxes, and all necessary mounting hardware. You can have better than new
sound with no modifications to your seats or Miata.
do I need the boxes? Why can't I just put the Millennium-5 or any other
small speaker in there?
A: You can, it just won't sound very good.
Speakers without some sort of baffling or enclosure have a huge low end loss
and a 'nasal' sort of sound. Not nice. This is because with an unbaffled
speaker sound waves from
the back side of the speaker tend to fight with the sound waves from the
front. It creates a cancellation effect where some frequencies are greatly
reduced and others reinforced. Also, sound from the left speaker cancels out
sound from the right and vice versa. Finally, unbaffled speakers have a much
lower power handling capability because there is no dampening of the cone at
This is why any decent
speaker system is always in an enclosure and why Mazda originally put the
speakers in enclosures. It's the right way to do it.
- so I need boxes for the speakers. Do you sell them?
you can order them here.
Q: How about wiring? Do you have
a made up harness for the Miata?
A: No. The newest NA Miata factory
radio is now more than 21 years old and while the original Panasonic radios
were good quality, most have been replaced by aftermarket stereos at this
point. So it's impractical for us to try and stock every type of adapter
needed. A company called Metra makes harness adapters and radio mounting
kits for the Miata and you can find all their kits on
Amazon. We have speaker
wire if you need some and the
proper crimp on connectors here. You can also get
speaker wire from Radio Shack and most home supply stores. We don't
recommend using any smaller than 20 gauge for the headrest speakers or 18
for the door speakers. See the step-by-step install guide on our site here
that includes a list of the items you'll need.
Q: How should the
headrest be wired in the Miata?
A: We include detailed wiring
information with every set of Millennium-5's sold and the information is
also available on-line by clicking here. (requires Adobe Acrobat Reader)