How to buy Speakers

Filed under: Articles, Electrical & Audio — on @ 9:55 pm

How to buy Speakers

This is part 2 in my series of (undetermined quantity)
articles about buying stereo equipment for your thirdgen.

Once you’ve got a head unit, your next step can vary based
on your priorities, but the next step for most people will be speakers… whether
it’s 1 pair, or 2 pair.

Writing about buying speakers is a lot more difficult than
writing about buying a head unit, because there is a heck of a lot more
subjectivity involved. Head unit A and
head unit B don’t really sound much different, so it’s generally a matter of
comparing features. That’s not the
case with speakers. Every two speakers
on the market sound different, so ultimately you need to audition them yourself,
and trust your own ears. Because of
this, this article will not only tell you about speakers, but it is going to
attempt to teach you how to listen to them, and to evaluate what you hear.

So… let’s start with the
objective part of speakers… their specifications.

Specifications

They’re all crap, so just ignore them.

Power handling depends on too many other factors that
aren’t explained in the ratings, so that specification for both RMS and peak
power handling can be generally ignored, or used as a guideline at best. I guarantee that any speaker on the market
won’t handle its rated power if you feed it a 20hz test tone, but most of
them will probably take 3x their rated power at 1khz. There’s also the issue of “handling” the
power vs. turning it into useful, undistorted music. I’ve seen plenty of speakers physically
handle their rated power without damage, but manage to reach their full
excursion with considerably less power. Anything above the amount required to reach full excursion is just
going to cause nasty clunks, bangs, and grossly distorted sound, so who
really cares if the speaker can “handle” it?

Frequency response numbers are another crock. Nobody’s 4×6 is going to produce useable
output at 50hz regardless of what the specifications claim. As with other specs, this one can be
heavily manipulated by various smoothing (averaging) techniques, and other
various tricks (in-car vs. anechoic measurements) to make a turd look like a
diamond. Furthermore, even a speaker
with a razor-flat frequency response could still sound like hell. There’s a lot more involved in producing
clean, accurate, low distortion sound than getting a flat frequency response,
although that’s still one of the most important aspects. Drivers with high distortion can still be
implemented with flat frequency responses, but will have various undesirable
qualities.

I can’t think of any other specifications that are even
included with most car speakers, but if there are any, they’re just marketing
crap.

How a Speaker Works

Next it may be a good idea to give a bit of background
information on just what a speaker is, and how it works. Short answer: A speaker is a transducer; it converts
electrical energy into acoustic energy.

Longer answer: Most conventional speakers (ribbons and
planars aside) have a copper coil that’s wrapped around a former. Attached to the end of that former is a
cone, or a dome. The coil sits in a
gap surrounded by a magnet. When
electricity passes through the coil, it is going to want to move away or
toward the magnetic field that the magnet is projecting onto the gap that the
coil sits in. This causes the coil
(and the cone/dome attached to it) to move forward and back as the electrical
signal passes through the coil. The
cone/dome is moves the air in front of it (and behind it) to produce
sound. See Figure 1.

One problem with speakers is that it is very difficult
(impossible for all practical purposes) to build 1 speaker that can
accurately reproduce signals across the entire range of frequencies that the
human ear can hear. In general, the
average person’s hearing is said to be able to recognize sounds ranging from
20hz to 20,000hz (20khz). Since a lot
of you reading this are still teenagers, you might actually still be able to
hear 20khz, though it’s not likely. Most people’s hearing doesn’t extend that far, and rest assured, as
you age, yours won’t either. By the
time you’re 50, you’ll be lucky to hear a note above 12khz. Boom your stereo much and it’ll be more
like 8khz. Boom all the time, and by
the time you’re 50, your life will sound like AM radio. So anyway… one speaker can’t produce
20-20khz signals properly. To produce
reasonable output at 20hz, you need a large driver that can move massive
amounts of air by moving back and forth 20 times per second. Think of this like a diesel engine, pumping
massive amounts of air through the engine at very low rpms. This big, massive speaker that’s capable of
moving that kind of air, has no chance of being able to move back and forth
20,000 times per second to reproduce a 20khz signal. For this, you need a very small,
lightweight speaker. Think of this as
a small displacement formula 1 race engine. It’s small, with lightweight components that allow it to spin at rpms
drastically higher than that big clunky diesel engine. Since a larger speaker can generally
provide more bass output than a smaller speaker, you will usually find that a
larger pair of coax or component speakers (like 6.5”) may have a fuller,
deeper sound than a similar pair of 4” or 5 ¼” speakers.

Another issue is directivity. Once a soundwave’s length gets smaller than
the diameter of the driver reproducing it, off axis response suffers. In other words, even if your big massive
bass driver could somehow accurately reproduce that 20khz signal, it would
only be audible if you were perfectly in front of the driver. Move a little to the side or up/down, and
it’ll go away. This issue makes it
very impractical to use larger “full range” drivers in an environment where you
will be listening off axis… like in almost every single car in existence.

So we’ve established that one speaker isn’t going to cut
it. We need multiple speakers, each to
cover a limited frequency range. This
is where speaker design gets complicated. When you utilize multiple drivers to cover one range of frequencies,
you need to do it so that both of them don’t try to reproduce the same
frequencies. You want each driver to handle a certain range that it is best
suited for, and because having the same sound coming from 2 sources is
generally bad for a number of reasons. You need to use a crossover to block the high frequencies from the midrange or woofer, and to block
the bass frequencies from reaching the tweeter. Designing a good crossover is as much an
art as it is a science, and this is usually what really has the most profound
effect on how a speaker sounds, and is also one of the biggest areas of
cost-cutting, especially in budget designs. An idealized (and simplified) result is shown in Figure 2. Figure 2 shows a typical car setup where
the subwoofer is configured with an 80hz 12dB/octave low-pass filter shown in
blue. The midrange is configured with
an 80hz 12dB/octave high-pass filter and a 3,000hz 24dB/octave low-pass
filter shown in pink. The tweeter is
configured with a 3,000hz 24dB/octave high-pass filter shown in red. The combined response is shown in black.

Driver Materials

There are a lot of speakers out there, made from a lot of
different things from paper to carbon fiber. What effects do these different materials have? Generally, the more rigid the material is,
the cleaner it will play a certain range of frequencies, with lower
distortion and less energy storage. The problem is, the more rigid it is, the worse it’s going to be at
the high end of it’s range. For
example, let’s compare the two extremes… a poly cone to an aluminum
cone. Polypropylene cones are
generally flexible, while an aluminum cone is extremely rigid. An aluminum cone is likely to have lower
distortion in the bass and midrange frequencies than the poly cone because it
retains a pistonic behavior instead of flexing. But… at higher frequencies, that aluminum
cone is going to have a breakup mode where it basically rings like the
liberty bell. Very cheap aluminum
drivers often have secondary breakup nodes in the octaves below the primary
breakup, and since these are likely to be right in the range of frequencies
that you need the driver to play, it will make the driver sound extremely
harsh and “tinny”, and will be impossible to remove with the crossover. This poor quality is what can give metal
cones a bad reputation as sounding “metallic” or “tinny”. The poly cone won’t do this, because it
damps the breakup (it absorbs it). Other materials, such as paper, carbon fiber, and 95% of the speakers
out there that have a poly cone with some sort of magic pixy dust coating,
fall somewhere in the middle, trying to strike a compromise between clean
midrange output and minimal high frequency breakup.

So, why does this matter to you? The more rigid the cone is, the more severe
the high frequency breakup will be. Figure 3 shows the unfiltered frequency response of a typical aluminum
driver. The breakup in the aluminum
driver needs special attention in the crossover. It generally means that a steep notch
filter aimed at striking that specific breakup frequency is necessary. This not only adds to the cost of the
crossover, but it means that quality control on the speaker needs to be good
enough that the breakup frequency doesn’t vary from driver to driver. On good quality speakers this probably
isn’t a problem, but I wouldn’t touch a $75 set of coaxes that use a fancy
carbon fiber or Kevlar cone, because chances are that the crossover is not
complex enough to properly handle the cone’s breakup… especially considering
that 50% of their entire materials budget just got used up in the cone. Since most poly woofers have a smooth
rolloff, crossover design and implementation can be much simpler, which is
why poly is used in the vast majority of lower priced speakers. Figure 4 shows the unfiltered frequency
response of a typical poly driver. While everybody out there has their special secret ingredients, the
fact is, most of them are just adding useless crap to a poly cone so that
they can market it as the 8^th wonder of the world. The fact is, when dealing with inexpensive
speakers, the smoother the driver’s natural response is, the better, because
a cheap speaker will NOT use an expensive filter, so you are better off
sticking with drivers that don’t need one. Let your ears be the final judge, but in general, you’re better off
with less rigid materials like poly and paper.

When looking at more expensive, higher quality speakers,
aluminum and some exotic materials become a much more attractive option
because of their much lower distortion below the breakup frequency. However, even with a better crossover that
uses higher quality (and quantity) components, it still needs to be
implemented properly, so an audition is always necessary.

What about tweeters? You’re probably going to come across 3 different tweeter types
depending on your budget: Mylar
(plastic), soft domes (fabric or silk) and hard domes (aluminum, sometimes
titanium or magnesium). Mylar domes
show up generally only on the very cheap coaxes and in factory stereos (See
Figure 5). They’re extremely cheap to
manufacture, and their sound quality, while tolerable for OEM type systems,
is relatively poor. Hard domes share
the same sort of breakup issues that hard coned speakers share, except that in
most cases, the breakup is beyond the audible range (See Figure 6). However, in cheaply made hard domes, there
can be several secondary breakup nodes for many octaves below the primary
breakup node, and these secondary nodes will be in the audible spectrum. This breakup is what gives many hard domes
that signature “metal” sound that they are known for. For this reason, in general it is not a bad
idea to steer away from lower priced speakers that use hard domes, or at
least listen to them with more scrutiny during auditions. A high quality hard dome won’t have that
“metal” sound and can be very detailed and pleasing. Soft domes are the most commonly used
tweeters because, like poly cones, their behavior can be very easy to control
and will make crossover design simpler (See Figure 7). A well built soft dome can have
exceptionally low distortion just like a well built hard dome, but also avoid
the high frequency breakup problems. A
poorly or cheaply built soft dome, while not nearly as good as a better soft
dome, is likely to sound much better than an equally poorly built hard dome.

How to Listen to Speakers

So this brings me to my next step… a little
tutorial for how to listen to speakers when auditioning them. Listening to speakers is really quite a bit
more difficult than people realize, and because of this, many speakers are
designed specifically to appeal to you for the 5 minutes that you’re in the
showroom instead of providing you with long term quality. Let me explain. If you listen to a very high quality set of
speakers that was built specifically to have a ruler flat frequency response
and very low distortion, you’d probably think that they sounded a bit dull
and flat during a short audition. It
wouldn’t be until you had some real time to spend with them that you
discovered that in fact, they actually did everything right. Comparing them to another, far cheaper
speaker that’s got a little hotter treble and a little more boom in the bass,
your first impression would be to like the cheaper speakers better. Likewise, when comparing a low distortion
speaker to one with significantly more distortion, your initial impression
might be that the one with more distortion actually has more detail. When a speaker adds distortion, it gives it
an edgy sound that many people mistake for more detail that they hadn’t heard
with other speakers, when in fact, the reason they hadn’t heard it before is
because it’s not supposed to be there! However, over time, that distortion will drive you nuts.

So… how do you listen? First of all, it depends on how serious of
a listener you are. If you’re just a
casual listener, there’s no reason to spend a month teaching yourself how to
listen. But even without that sort of
preparation, in the long run you’ll be happier with a set of speakers that
has a smooth, pleasant sound instead of one that jumps right out at you. One quick and easy way to see how you’ll
like a speaker in the long term is to turn it up loud. Not so loud that you’re causing the speaker
or amplifier to distort, but loud enough that it’s hard to talk over it
without yelling. Listen at this level
for a couple minutes. Does it still
sound good, or is it starting to hurt your ears, seem too loud, or just seem
not to sound as good? Any of these
issues is a clear sign that the speaker has relatively high distortion, or a
very objectionable spike in the frequency response somewhere. A speaker that might jump out at you and
sound “lively” at low volumes might have that quality because of a poor
frequency response or high distortion, and at louder volumes, that quality
really becomes a major drawback. This
is a speaker that will constantly have you reaching for the volume knob to
turn it down, because you just can’t stand it anymore. Don’t buy this speaker. Buy the one that still has a clean, smooth,
pleasant sound at loud volumes, because chances are, this is the one that
you’ll be able to live with the longest. Remember that whether you realize it or not, most of your listening in
the car will be at levels that are significantly higher than what you’re
listening at in the sound booth. If
you don’t believe me, next time you park your car, don’t turn the radio
down. Leave it just how it was while
you were driving home, and next time you get into your car and turn on the
radio, pay attention to just how loud it is… you didn’t remember it being
that loud when you shut the car off, but it was.

So… you’re the type of guy that wants more
than just a “good” sounding set of speakers. You want something that’s really a very good speaker. How do you really become a critical
listener, capable of hearing and identifying the more subtle differences
between one speaker and another? For
the most part, experience, and lots of it. But, your learning process will go much faster if you have a fairly
good idea of what to listen for instead of trying to figure it all out for
yourself. I’m approaching 30 years
old, and I’ve been a hardcore audio nut for over half of my life, and I’m
still learning how to listen to speakers. It’s something that really does take many years of experience, but
here are some relatively basic pointers.

First of all, it’s essential to have some
music that you know very well and that is exceptionally well recorded. It’s good to have a combination of simple
and complex recordings with male and female vocals. The more familiar you are with these
recordings, the better you’ll be able to evaluate the speakers. It’s always a great idea to invest in a
good quality set of headphones, because for $50-100 you can get a very good
set that will have very low distortion, and because they’re so closely
coupled to your ears, you’ll be able to resolve an amazing amount of
detail. This will really help you
become familiar with the overall qualities of the music, although it won’t do
much to help you with identification of proper imaging and separation, but at
least you’ll know what the tonal qualities are supposed to sound like. It’s also very helpful to go to some high
end home audio shops and listen to the music on some very good speakers. This will help you build your listening
skills with respect to imaging, staging, and with detail resolution in a
non-headphone environment. Listening
to some lesser speakers with the specific goal of identifying its shortcomings
compared to the better ones is a GREAT way to learn the differences. A lot of what I mention below about
listening to the car speakers can and should be used when auditioning these
high end (and low end) home speakers in order to be able to identify
shortcomings. If you can, I would suggest
that you listen to the following speakers:

B&W 800-series (804s and larger)

Dynaudio Audience Series (Audience 72 and
larger)

Sonus Faber Cremona or higher

Jamo D830

Quad ESL

See Figure 8

There are hundreds of other fantastic sounding
speakers out there, but these are some that I’m personally very fond of, and
are speakers that I’ve found offer very low distortion and an overall
enriching listening experience. Each
one of these speakers sounds different, and they all have their shortcomings,
but they all do an awful lot right as well. Best of all, each of them has different strengths, so listening to
them all and picking out their differences will really be a useful exercise.

So now you’ve listened to a bunch of music,
and hopefully, you had the chance to listen to some very good high end
speakers. Maybe now it’s time to
listen to some car speakers. Start off
by popping on one of your cds, and turning the speakers up to a reasonable
volume. Get the easy stuff out of the
way first. Are there any objectionable
issues with the frequency response? Are they too bright (too much treble), too dark (not enough treble) or
somewhere inbetween? Is the midrange
too forward (in your face), too laid back (where’d the vocals go!?), or
inbetween? Is the midbass overpowering
and unnatural, absent and thin sounding, or somewhere inbetween? How are vocals? You should be listening to male and female
vocals, because they will bring out flaws in different ranges. Generally, I’ve found that differences in
the 150-500hz range has the most profound effect on male vocals. Too much low frequency energy makes him
sound unnaturally bassy. Too little
makes it sound thin and hollow, with no warmth. With female vocals, since they have much
less low frequency energy in their voices, I seem to find that variations in
how they sound seem to correlate with the 400-1khz range. Too much upper frequency output can make a
female voice sound shrill and harsh, too little makes it sound recessed and
undetailed. Both male and female
vocals are dependant on a clean response over a wide range of frequencies,
but I’ve found that it’s easiest to find the flaws using the males for the
lower and females for the higher range of vocals. Bass response (and to an extent, even midbass)
is going to really be hard to judge on car speakers, because a shop’s sound
board is a horrible environment for speakers, and is not a whole lot like a
car environment. But, you can still
compare one to the next in terms of the amount of output and how detailed it
is. Do all bass guitar notes have the
same volume, or are some louder than others? Just keep in mind that when you put it into your car, it’s going to
sound totally different. If you’re
running subs, this will be less of an issue, because you’ll have these
filtered anyway.

So once you get past the frequency response
issues, you can start to listen to more of the detail oriented stuff. Keep in mind that this stuff all hinges on
the quality of the recording, and your familiarity with it. All of this detail oriented listening is
fairly worthless if you’re not already well aware of what the recording has
to offer. How clearly can you focus on
one individual instrument? Can you
listen to it and hear all it has to offer, or is it hard to pull that
instrument from the rest? A better
speaker will resolve more detail and allow you to easily distinguish each
instrument and listen to it exclusively. You should be able to pick out any instrument to listen to. Lead guitar and rhythm guitar should be
clearly distinguishable. Bass guitar
should be clear, and separate from bass drum. You should be able to pick out individual bass guitar notes, not just
have a low frequency blur. Can you
hear the clean upper frequency harmonics of the guitar strings? Can you hear the subtle inflections in the
singer’s voice? What about the dynamic
impact? Do drums have a hard impact
like a live performance, or is it more relaxed?

For those who aren’t real sure what it is,
imaging is the ability of a speaker to provide a pinpoint location for
various things. For example, a
singer’s voice should sound like it’s coming from one very specific location…
not from all over your dashboard, and shouldn’t shift back and forth with
changes in pitch. It should stay in one
tiny, tightly focused spot at all times. This should hold true for all instruments and voices, unless they were
specifically intended to have a different effect. Staging (or sound stage) describes how
accurately these images are placed. Generally vocals would be perfectly centered. Perhaps there’s a guitar that’s supposed to
be ¾ of the distance toward the left and cymbols are 1/2 way between center
and right. Imaging and staging are two
very important aspects to a quality speaker, but I’m not really going to
mention much because any differences from one speaker to the next will be
largely overshadowed by your installation. Where you put the speakers and how you aim them will have a profound
effect on imaging, so whether or not they image well in a retailer’s sound
board really isn’t going to teach you much. The fact that a typical sound board has every speaker sharing a common
chamber means that you’ve got 1 speaker and 50 poorly tuned passive
radiators, so it’s not likely that you’re going to get a good image anyway.

Suggested Music

As long as you’re going to go listen to a
bunch of stuff, I’ll provide you with some suggestions for various music and
what to listen for. If you choose to
use any of this music, be sure that you’ve spent a lot of time with it so
that you’re familiar with it.

Eagles, Hell Freezes Over, particularly Track 6 “Hotel California” (Figure
9)

This cd is my number 1 cd, both for pleasure
listening and for speaker evaluation. Not only is it a phenomenally well recorded live album, but I’m
exceptionally familiar with it, especially Hotel California. What amazes me however, is that I still
learn more about this song as I listen to it on better speakers, despite
having heard it thousands of time already. This song starts off with thundering deep bass from a bongo drum that
Timothy B. Schmidt is pounding on. After the first few, you’ll begin to hear two clearly distinct tones,
the first low and the first high. On
lesser speakers, you’ll have a hard time distinguishing between the two. This may be below the typical range of many
speakers you listen to, especially 4×6s, but none the less it’s something to
listen for since the upper harmonics are what really cause you to hear the
differences. Anyway, shortly after the
bass, you can hear a maraca in the right channel, then another in the
left. These should be clear and
lifelike… not harsh, but very present. Once the actual music starts, you should be able to hear 3 different
and distinct guitars. Joe Walsh
pounding away on his guitar, Don Felder on his, and Glen Frey on his. On most speakers, you’ll never be able to
latch onto any of the individual guitars and listen to it cleanly and clearly
without the others interfering. This
requires a VERY good set of speakers, and it requires them to be in an
exceptional installation. Don Henley’s
voice should be realistic sounding. On
a lot of speakers it sounds too laid back. While it should never be in your face, it should not get drowned out
by the rest of the music either. His
voice shouldn’t resonate or be boomy, but should also not be thin and weak
sounding. Also take a moment and
listen to track 5 “Tequila Sunrise”. In this song, Glen Frey’s “ssss” sounds can be harsh (known as
sibilant) and very unpleasant. The
speakers should not exhibit this. All
of his vocals, including his “ssss” should be smooth and lifelike without
being harsh or piercing.

Tom Petty, Greatest Hits, “Mary Jane’s Last Dance” (Figure 10)

This is another song that I use a lot. You should be able to clearly distinguish
between the 2 guitars… one to the right and one to the left. You should be able to listen to either one
without interference from the other, and you should be able to pick out the
subtle detail, especially of the left one. Tom Petty, while always nasal sounding, should still sound realistic,
like he’s singing right in front of you.

Dire Straits, Brother in Arms, “Money For Nothing” (Figure 11)

The 80s are alive again! Be careful with this song. This song has a tendency to sound PHENOMINAL
on even mediocre speakers. Every time
I use this cd, I wind up just jamming to the tune instead of actually
evaluating things. Anyway, there are a
couple things you want to use this song for. Overall, the percussion on this song is very well recorded, and should
sound very natural. Bass drum should
be powerful but realistic. It
shouldn’t sound like the boom of a rap song, it should sound like a bass
drum. The snare should have a
powerful, lifelike, dynamic snap. It
should sound live, not laid back and smooth, but also not harsh or
unpleasant. Cymbals should be clean
with a somewhat laid back sound, but still plenty of air and shimmer. These won’t quite sound live, but they’ll
still sound clean. Knopfler’s guitar
playing is near god-like and sounds fantastic on this song, but I’ve found
that it still sounds good on mediocre speakers because more distortion on an
electric guitar sound that’s already been distorted intentionally can be hard
to pick out. Either way, don’t put
much stock in how his guitar sounds because it will sound good on
anything. Still, it should have good
dynamics, and should convey the lighter details without sounding overly
sharp. Knoplfer’s voice should sound
realistic and hearty. It has a nice
deep sound to it, but shouldn’t be boomy or unnatural sounding.

Alison Kraus and Union Station, Live 2 CD set (Figure 12)

Pick whatever songs you want on this one…
they’re all exceptionally well recorded. In this all acoustic group, you should once again be able to pick out
the 4 individual instruments: Jerry Douglass on dobro, Dan Tyminski on
guitar, Ron Block on banjo, and Kraus on violin, as well as Barry bailes on
bass (cello, not bass guitar) behind all of it. It’s been a while since I’ve
listened to it, so I forget who’s where on the soundstage, but the 4 are
spaced evenly from left to right with the bass in the center rear. Kraus’ voice is haunting and intimate, and
completely natural sounding. Dan
Tyminski’s voice is also very natural sounding. The better the speakers are, the better
this whole album sounds.

Coax vs. Component speakers

A coax speaker usually refers to the type of speaker
that’s got the tweeter mounted right in front of the woofer (coaxially;
sharing the same axis, hence the name)(Figure 13). This type of arrangement
is convenient because it can drop right into stock locations and you don’t
need to mount anything else. On the
other hand a set of components (named because it comes with multiple
components) has a separate woofer and tweeter, as well as a separate
crossover that’s got to be mounted somewhere (Figure 14).

Your main advantages with coax speakers are cost and
installation convenience. Although
it’s not always the case, typically a coax speaker will be less expensive, because
it’s usually marketed toward people who are looking for an affordable, easy
upgrade. Due to packaging constraints
and cost concerns, most coax speakers have very simple crossovers, which is
why material choice can be so critical. As I mentioned above, while they may be worth a listen, typically
you’ll want to stay away from low priced coaxes with rigid woofer materials
and hard tome tweeters and stick with a poly woofer & soft dome tweeter
combo. Of course, let your ears be the
final judge.

Some “coax” speakers have more than just a woofer and
tweeter. Some are 3 and even 4-way
designs. For the most part, this is
largely a gimmick and unless your ears tell you otherwise, don’t waste your
time. Most of these 3 and 4 way
designs are still just a true 2 way design, with added drivers that are
completely non-functional or only semi-functional. It’s usually marketing crap, which is why
they’re usually in the lower priced categories. There are a lot of drawbacks to this type
of design that can’t be overcome easily or affordably. For one, they typically block a major
percentage of the woofer, so you wind up with attenuated output at the top
end of the woofer’s usable range. Secondly, there just isn’t room for the overly complicated crossover
that would be necessary to make such a design perform properly.

Component speakers don’t have to conform to the tiny
packaging restraints imposed on a coax speaker, so it opens up the
possibility to produce a much better product. Larger, better quality tweeters can be used, and larger, far more
advanced crossovers can be utilized. This doesn’t mean that there aren’t still hundreds of terribly
designed component sets out there, only that there is more flexibility to create
a better product.

Other than the potentially better component quality, the
other advantage to component speakers is the ability to install them in
arrangements that are more ideal. You
can mount and aim the tweeter independently from the woofer. Not only does this give you the luxury of
being to aim the highly directional tweeter for optimum imaging without
having to tweak the entire speaker, but it allows you to position the tweeter
so that the phase of the two drivers around the crossover frequency is more
ideal. I don’t want to get into that
whole issue here since this writeup is already turning into a novel, but
trust me that it’s an advantage.

The drawbacks to a set of component speakers are that the
installation is going to be more challenging, the higher quality is going to
cost you more, and that in addition to finding a home for the woofer and
tweeter, you’ve also got to find a home for the crossovers. Overall however, if you’re after the best
sound you can get, this is probably the way to go.

Where to put the speakers

Now that you know how to listen to speakers, you need to
decide where you want to put them so that you can figure out what size and
style you want, and then you can finally go audition some.

In a non-Bose equipped thirdgen (GTAs excluded), you’ve
got 4×6” speakers in the dash and 6×9” speakers in the sail panels (Figure 15 and Figure 16). Bose equipped Camaros had speakers in the
kick panels, and speakers in the rear hatch cover. (Figure 17) Since the Bose setup was such a pitiful
combination of head unit, amplifiers and speakers, I’m going to assume that
if you’re interested in upgrading speakers, you’re also going to pitch the
head unit and amps, so the non-Bose speaker locations can still apply. If you have a GTA, you’ve got the same
crappy 4×6” front speakers, but instead of crappy 6×9s, you’ve got another
pair of crappy 4×6s in the back, augmented by a crappy 5.25” “subwoofer”
though I use that term very loosely. One interesting tidbit of information is that the primary difference
between the base stereo and the premium stereo (non GTA) besides adding a
head unit with a 5 band eq (but still just as pitiful sounding as the regular
one) was that they used less restrictive speaker grill inserts in the dash
pad. Instead of the grills with
plastic slats, they used a metal grill with cloth over it. It provided a noticeable improvement in high
frequency output.

So anyway, if you’re looking to simply improve a little
bit on the factory sound, or if you’re on a real tight budget, sticking with
the stock speaker locations is the way to go. If you’re buying both front and rear speakers, make sure to stick with
the same brand and model line when possible. The goal here is to have the most similar sound quality possible from
front to back so that certain parts of the music don’t become more apparent
in the front or back.

Front Speaker Locations

There are some pretty significant drawbacks to the stock
dash location that you should be aware of. The first is that the physical location is too small to fit something
larger than a 4×6” speaker without significant modification. In many cases, specifically 85-up Firebirds
and 90-up Camaros, the space on the driver’s side is so cramped that many
4×6” speakers won’t even fit. These restrictions
make it virtually impossible to use a very good speaker in this location…
you’re basically stuck with mediocre and lower end stuff.

Another significant drawback is that it is very difficult
to get good imaging for one passenger, and it’s impossible to get good
imaging for both passengers. The most
important part to good imaging is to have equal SPL from both speakers and
equal path lengths so that the sound arrives at the proper time. I’ll save the details for a later article,
but the quick and dirty is that your brain localizes sounds by comparing the
differences in loudness and time delay between the two ears. If something happens to your left, your
left ear gets a slightly louder version of the sound than your right ear, and
it gets that sound a slight bit sooner. You can adjust your balance control to help compensate for the fact
that the closer speaker is significantly louder. This will help give you a broad, even
soundstage, but because the path lengths are still way off, it confuses your
brain and makes it difficult to recreate a stable, accurate image. Some new head units have time alignment
features that help you to adjust these tiny differences in arrival time, and
can provide a significant improvement over just using a balance control. However, the image from your dash speakers
is only going to get so good, and whatever you do to make it image better in
the driver’s seat is going to make it that much worse for the passenger.

The last main drawback to the dash location is that the
majority of your sound is being reflected off of the glass. This causes a couple problems. One is that your reflected sound is going
to combine with the directly radiated sound, which is the same as having the
sound come from 2 unique sources. Since their path lengths to your ear differ, you’re going to get a
comb-filtering effect in which some frequencies are cancelled, and some are
reinforced. The combination is going
to be a very uneven frequency response that will result in a lost of detail
and realism, as well as phase issues that will ruin imaging.

Another possibility is to stick the speakers down very low
into your doors (Figure 18). If you have manual
windows, you can fit up to a 5 ¼” (and most 6.5” brands) in the lower front,
though you may have some interference issues with the window crank and the
kick panel plastic. If you have power
windows, the power window motor sits right in this location, so you will have
to build out the door a significant amount in order to fit the speakers. If you use component speakers, you can
flush mount the tweeter into the kick panel. This will allow you to use larger speakers than the dash location, and
will also help improve imaging. Since
most car speakers are designed to work in a large volume like that of a door,
your overall bass output will be improved. The fact that you can fit a larger speaker than your dash will also
allow bass to be much more improved. One drawback to using the door is that unless you apply generous
amounts of sound deadening material, the doors are going to resonate badly. Your speakers will also be exposed to the elements,
which will accelerate wear. Lastly,
running speaker wire to the doors can be difficult. If you have power windows, building the
door out to make the speakers fit can be very difficult, and even harder to
make aesthetically pleasing. If you’re
paying a pro to do the work, this will be an expensive option due to the
custom work involved.

The last common location for speaker placement in the
front of a thirdgen is into the kick panels (Figure 19). This location really does help overcome a lot of problems associated
with kick panel and door locations. Your path lengths are as close to equal as you’ll be able to achieve
in the car, so your imaging and soundstage can be exceptionally good. You can fit large, higher quality drivers,
and you have a lot more freedom to aim and position them for best
results. With a properly set up kick
panel setup, your soundstage will be above dashboard height, and will be
fairly far forward… usually as far forward as the furthest point of your
windshield or more. There are 2 drawbacks
to kick panel locations. The most
significant is the lack of airspace for the woofer. Since most car audio speakers are designed
for large spaces (infinite baffle) like a door cavity, they perform poorly in
very tiny enclosures, like a kick panel. Their low bass response disappears, and the output in the range
between 150-400hz becomes exaggerated. The most common fix for this is equalization. The second drawback is that people’s legs
can block the speakers, causing a high frequency attenuation of a few
dB. Because the small interior is so
reflective anyway, the difference in sound with and without somebody’s legs
in the way is really much less severe than you would think, and is a small
price to pay in exchange for the tremendous benefits in imaging and speaker
quality that kick panel placement allows. One last drawback is the difficulty and/or expense associated with
this type of installation. If you’re
not handy enough to create your own set of kick panels, you’ve got to buy
them or have them custom made. Q-Logic
sells ABS plastic kick panel pods that can hold up to a 5.5” woofer and a
tweeter for around $100. These are
relatively poor quality, but with additional fiberglass and sound damping
material, they can be respectable. Another option is to have one of the guys from the thirdgen message
board build a set. There are a couple
guys who do this, and both provide kick panels that are significantly higher
quality than the Q-Logic pods, and at a price that’s substantially lower than
you’d pay for a shop to build them. Still, this adds a significant expense on top of the cost of the
speakers themselves, and really only makes sense for those who demand the
best from their system.

Rear Speakers

As mentioned before, the most common rear speaker size is
6×9”, located in the sail panels (Figure 16). There is ample room for speakers with deep or large magnets, although
tweeter protrusion to the front may be an issue. In worst case scenarios, you should be able
to modify the stock cover to add the extra space that you may need. If your car came with 6×9s, the new pair
will be a bolt-in affair. If your car
came with the Bose or GTA stereo, then you may need to find or fabricate
adapters that bolt to the body opening that can accept the 6×9s. These can be cheaply located from salvage
yards or the thirdgen classifieds.

One thing that you may want to consider is rather than
upgrading all 4 speakers, use the full budget allocated for speaker upgrades
for the front speakers only. While
some people prefer the “all around you” sound, if you’re the type that
prefers a good realistic soundstage and better overall sound quality,
spreading your money among just 2 speakers instead of 4 will pay off. You will be able to put that money toward a
better quality set of speakers, or toward a different configuration, like
kick panels instead of sticking with the stock dash location. Either way, you can retain your stock 6×9s,
which are sufficient if you just want to add a little bit of rear fill for
ambience. In fact, the stock speakers
are perfect for this because they don’t have a lot of high frequency output
that can pull your soundstage back.

Recommended Brands

This is tough. Every speaker sounds different, so you really need to decide for
yourself, which is why I spent so much time explaining what to listen
for. But, the usual low quality brands
can be avoided.

Particular brands that you may want to consider
auditioning include anything from Boston Acoustics, JL Audio, CDT, midlevel
and higher stuff from Alpine and MB Quart, and for high-end type of stuff,
look at Dynaudio, high end JL Audio, the new high end Polk components,
Rainbow, Seas, DLS, and plenty of others.

As I hope you’ve realized by reading this novel, is that
there’s an awful lot to choosing a pair of speakers. This will be the most subjective, and
probably most difficult piece of equipment you choose. It will also have the largest impact on the
overall sound of your stereo system. I
can’t stress enough that you really need to audition the speakers you plan to
buy. Mail ordering your stereo
equipment can save you a ton of money, but with something as subjective as
speakers, you really, really need to audition them to be sure you’re getting
what you want.

Happy hunting!

Hope
this helps.

Article and Figures by Jim Irace (Jim85IROC) unless
otherwise noted