Car Audio Tweeters: How to Aim, Place and Tune Them

21 hours ago

8 min read

A tweeter is the small speaker that plays the top of the music: cymbals, fine detail on strings and the air around instruments. Peter Steinbacher of Pssound, a UK high-end car audio installer, says it decides how high-end a whole system can sound (watch). His core idea is that the detail you get depends on the driver you start with, where it sits and which way it points, and that most harsh tweeters are really untuned cabin peaks.

The short version

The tweeter sets the ceiling for a system, because detail it does not deliver cannot be tuned back in.
What counts is fine detail between about 2 and 16 kHz (kilohertz, a measure of pitch), above all at 8–16 kHz, not extension above 20 kHz.
Keep each tweeter within about 20° of the listener, for both front seats, and never aim the two at each other.
Keep the tweeter close to the midrange, at a similar height.
A harsh tweeter is usually an untuned 2–6 kHz peak in the cabin, so tame it with measurement and EQ (tone adjustment) instead of limiting it to the highest notes.
Keep sharp edges and fancy grilles away from the tweeter's rim.
For the most detail Peter uses AMTs (air motion transformers), and he has come round to super tweeters.

What the top end really needs

For most people the music stops at about 16–17 kHz, and for some, often once they are past 45 or 50, it stops at 12–13 kHz. Try it yourself: play a tone from a signal-generator app and raise the pitch until it disappears. So Peter says a tweeter's magic is not in the super-high frequencies. It lives in the 8–16 kHz band, which still carries many instruments and a lot of detail.

What separates a great tweeter from an average one is resolution: how well it separates fine layers of detail and opens up depth in the stage. It is not on a spec sheet. Peter says any tweeter, even a $20 one, can be EQ'd to the same curve up to 18–19 kHz and still not match a good one (watch). Detail a tweeter lacks cannot be tuned back in.

Compare tweeters by ear before installing them: hold two, play well-recorded cymbals you know, and switch quickly between them.
The most revealing tweeters, such as Accutons and AMTs, are the least forgiving. They expose flaws in the tune and the install, so in the wrong hands you end up disliking them (watch).

Aim each tweeter within about 20 degrees

High frequencies are very directional, so a tweeter angled away from you loses top-end detail. On-axis means pointing straight at you, and off-axis means angled away. Peter's rule of thumb: point each tweeter within about 20° of where the listener sits. That is enough to get the top-end detail without EQ, and it sends less sound onto the side window (watch).

The cost of pointing away is large. On a good manufacturer's plot a tweeter can be flat to 22 kHz straight on, start rolling off from about 10 kHz at 30°, and be 15–20 dB (decibels, a measure of loudness) down at 20 kHz by 60° (watch).

Aim for both front seats. In the Porsche Cayenne the aiming keeps both occupants within about 20°. Many cars are set up for the driver alone, and Peter has had to demo cars from the passenger seat with no top end above 8 kHz.
Do not point them dead at your ears. The driver-side tweeter is so close that it sprays sound onto you and the side window, which worsens reflections. In his builds on-axis means roughly 10–20°.
Never point the two tweeters at each other. That leaves the driver's one about 70–80° off-axis, so it plays nothing above about 10 kHz, and boosting it with EQ would swamp the passenger with treble (watch).
Response matters more than the reflections forum users fret about, since a car has them everywhere. He still avoids firing the driver-side tweeter at the side glass.
Test it: play a track with lots of cymbals and move your head until your ears line up with the tweeter. You will hear more detail.

Keep the tweeter close to the midrange

The tweeter's position follows the midrange (the mids), the driver that plays voices and most instruments (see our midrange guide). In the Mercedes CLK the mids went in the A-pillars (the posts either side of the windscreen), so the tweeters went in the sail panels (small trim pieces by the wing mirrors). With dash mids they would have gone on the pillars.

Do not split them in height. With mids low by the dash vents and tweeters halfway up the pillars, the stage splits into low mids and high highs, and in 2020 Peter said he could not live with that (watch).
Do not spread them too wide. Narrow dash mids with tweeters in the sail panels widen the stage but give two focus points, and Peter would not suggest it.

Grilles, edges and mounting

Diffraction is sound bending around an edge, which upsets the response. Peter says nothing sharp should sit over the edge of a tweeter. Factory grilles can colour the sound too: the Boxster's tweeters sounded very harsh under the dash grille, yet he says that was the environment, not the speaker. Once the response was tuned flat, they sounded beautiful (watch).

Aim matters more than a flush look. On the CLK a flat-mounted tweeter pointed a bit too low, so Peter extended the platform and bonded the mounting rings at the right angle (watch). More in our fabrication and mounting guide.
Do not glue the tweeter's original mount into the pillar. For the V-Class's Focal Utopia tweeters they 3D-printed a small cup and bolted the original mount to it, so it can move to the next vehicle (watch).
Think about rain: water can drop onto a sail-panel tweeter when the door opens in heavy rain. White ceramic should be fine, but it would mark a graphite-finish Accuton.

Harsh tweeters, crossover points and tuning

Peter says harsh tweeters are usually untuned ones. The cabin typically leaves a lot of excess level at 2–6 kHz, where the ear is most sensitive. People who cannot tune then blame the tweeters, sell them and buy others that behave much the same in the same spot. In his words, "it's not the tweeter, it's the environment" (watch). He rejects the idea that metal domes are harsh by nature: once the response is flat, a metal tweeter sounds just as soft as a soft dome.

Do not set the crossover (the point where the mid hands over to the tweeter) at 6–8 kHz just to make a tweeter bearable. Learn to tune instead (watch).
How he EQs: pull everything above the target line down, then lift the top end by only about 3–3.5 dB. Keep it linear (flat), because rolling it off by 5 or 10 dB from 2 or 4 kHz hides detail (watch).
Measure safely: put a 1 kHz high-pass (a filter that blocks everything below 1 kHz) on first, and measure at normal level, about 85–90 dB on pink noise (a steady hiss).
Use a tweeter from at least twice its Fs (the frequency where it naturally resonates), preferably three times, so an Fs of 1 kHz means from 2–3 kHz (watch). A low Fs does not mean cross low: that suits quiet 85–90 dB listening on a couple of watts, but for 100, 105 or 110 dB with decent power, cross higher. More in our guide to crossovers, EQ and time alignment.

Do you still need a tweeter with wideband mids?

A wideband is a small driver built to play from the midrange (about 150 Hz in one example) all the way up through the treble, with no separate tweeter. Peter's default is that a system is always better with a good tweeter (watch). In a car a wideband cannot be kept on-axis, so a little top end is lost, and for the no-compromise result he adds a tweeter, even one that only plays above 10–12 kHz. By 2024 he put it more strongly: tweeterless widebands measure out to 17–20 kHz, but most play the top end unnaturally and cannot reach an AMT's resolution (watch).

The risk: a tweeter you cannot integrate with the mid sounds unnatural, which is worse than a wideband alone. That is why many people skip it.
The exception is a small wideband in a dash tweeter spot. In the 2020 VW Caddy, 2-inch widebands in the factory dash tweeter location worked from about 300–330 Hz up and replaced the tweeter (watch). In the 2024 Caddy, with only door midbass below it, a tweeter would not have worked: the dash wideband covers the mids and the top end together (watch).

AMTs and super tweeters

An AMT is a rectangular tweeter in which a folded, accordion-like foil moves sideways to make the sound, instead of a dome pushed by a coil. It looks like a ribbon tweeter but is a different technology. Peter says its moving part is so light that you get more detail, air and space around instruments, and it measures to 30 kHz and beyond (watch). He has not found that character in any other car-audio tweeter. Keep in mind that Pssound sells its own, made with Mundorf: the U60S-PS1.1, listed at £799.

Bigger plays lower. With the right crossover type, the U60 can be crossed as low as 2 kHz, so it works as a full-size tweeter. The U80 plays only about 200 Hz lower and handles about 20% more power but is harder to install. The small U40 (about two-thirds the size) suits use above about 5–6 kHz (watch). Even large AMTs need a midrange that plays up to at least about 2 kHz.
Orientation matters. Mounted vertically, an AMT spreads sound widely side to side but narrowly up and down, so it must be aimed at head height. Turned horizontal, it covers short and tall listeners and keeps energy off the side glass, but it favours the driver and the passenger loses some detail (watch). Practice has moved around: the 2023 Citroen went horizontal, but by 2025 Peter said he personally prefers vertical. Measure both in your car.
Super tweeters are small extra tweeters that add the very top above a main one. By 2024 Peter admitted he used to be sceptical, but said the pair in his own S-Class definitely makes a difference, as a finishing touch rather than a day-and-night change (watch). That car has them because its factory sail tweeter is about 70° off-axis, and boosting it with EQ would give the passenger far too much top end. He still prefers one full-size AMT that plays down to about 2 kHz over small ones added on top.

Common mistakes to avoid

Judging a tweeter by how high it plays or by its spec sheet, when detail between about 2 and 16 kHz is what counts.
Aiming the tweeters at each other, only at the driver, or dead at your ears.
Mounting the tweeter far from the mid, whether well above it or wide apart.
Crossing a tweeter at 6–8 kHz to hide harshness, or crossing it low just because it can play low.
Blaming the brand or the metal dome and swapping tweeters before measuring and tuning the cabin.
Leaving a sharp grille or trim edge around the tweeter, or bonding its original mount into the pillar.

Watch Peter explain it

This is an independent, plain-English summary of Peter Steinbacher's public YouTube videos, written by VA3 Car Studio. It is not affiliated with or endorsed by Pssound. The links jump to the moment in each video where he makes the point.

Part of our series: Car audio lessons from Pssound, start here