Auto Planet · Koramangala, Bengaluru · Est. 1999
Anatomyof a of a3-Way Active System
A factory speaker tries to play the whole spectrum from one cone. We don't. We split the music into three bands, hand each band its own driver and its own amplifier channel, and let a DSP decide who plays what, how loud, and exactly when.We split it into three bands — each with its own driver, its own amplifier channel, and a DSP deciding who plays what, how loud, and when. Scroll to take one apart. — built with the hardware Auto Planet actually fits: Brax, Helix, Audiotec Fischer.
01 — The sweep
Subwoofer
20 – 80 Hz · boot · custom enclosure
The floor of the music. Kick drum body, the low string on a bass guitar, the pressure you feel in your chest before you hear it. Below 80 Hz your ears can't tell where sound comes from — which is exactly why the sub can live in the boot and still sound like it's under the dash.
02 — The crossover
Four slopes,locked by software.
Passive
One amp channel feeds a box of capacitors and coils bolted behind the door card. It burns power as heat, the slopes are whatever the parts happen to do, and nothing can be changed once the trim is back on.
Active
Every driver gets its own amplifier channel, fed straight from the DSP. Crossover point, slope, phase, EQ and delay are numbers on a screen — tuned to your car, your seat, your ears, and re-tuned any time.
03 — Time alignment
Your right earis closer.
In a car nobody sits in the middle. The driver's door speaker is forty centimetres away; the passenger's is more than a metre. Sound covers that gap at 343 m/s, so the near side arrives first and the stereo image collapses into the door beside you.Nobody sits in the middle of a car. Your near door speaker is forty centimetres away, the far one more than a metre — and at 343 m/s the near side arrives first, collapsing the image into the door beside you.
The DSP fixes it by holding the close speakers back — microseconds of delay, measured per driver from the driver's seat — until every wavefront lands on your ears at the same instant. The image lifts off the doors and sits on the windscreen, centred, where the band should be.
04 — The difference
Stop reading.Listen instead.
Headphones, or the car. Laptop speakers cannot show you the bottom two.
Both paths are level-matched by measurement, not by ear — each one is rendered and weighted before you hear it, so the switch is a change of response and never a change of volume.
Stopped · A, untuned cabin
What A is doing to the signal
B is this list not happening. Press A and B to switch without reaching for the mouse.
This is a simulation, not a recording. Both sides are generated in your browser: a synthesised loop, and the same loop with a cabin’s typical response and arrival error applied to it. It demonstrates what correction does — it is not a recording of an Auto Planet system, and no car is claimed to sound like this file. The only way to hear a real one is to bring us yours.
05 — The signal chain
One song,five stages.
A representative flagship build, drawn from installs Auto Planet has documented — exact components depend on the car and the budget. Scroll to follow the signal.
And this is not the ceiling. Our four-way active front / two-way active rear builds run a fourteen-channel processor with twelve channels of amplification on board, a Brax GX for the centre, and a Helix flagship amplifier driving the rear.
Built — Koramangala
Every diagram on this page is a drawing of this.
06 — Your turn
Hear it in your car.
Everything above is theory until it is your car, your seat and a track you already know by heart. Bring it to the Koramangala workshop and hear what three ways, four amplifier channels and a properly tuned DSP actually do to a recording.
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Auto Planet · Shop no. 703/4, 3rd Block, Behind Koramangala BDA Complex, Bengaluru 560034
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