Subaru has run a Harman Kardon partnership across most of its range for more than a decade — Forester, Outback, Legacy, Impreza, Crosstrek and WRX all offer a Harman Kardon-branded system on upper grades, tuned in collaboration with Harman's engineers from each model's development stage. Given how popular Outback and Forester in particular are with Australian buyers, we're building out a dedicated upgrade path across the range.
What's actually in a Subaru's factory system
Harman Kardon coverage varies by model: Forester runs 8 speakers at 440W using Harman's DSP Technology; Legacy and Outback step up to 12 speakers at 576W using GreenEdge technology; WRX/STI runs 9 speakers at 440W with DSP Technology; and Impreza/Crosstrek run 8 speakers at 432W with GreenEdge. GreenEdge is Harman's efficiency-focused driver design, while Clari-Fi is a real-time processing technology that analyses compressed audio and corrects waveform deficiencies to improve playback quality. Base-grade Subarus without the Harman Kardon option run a more modest unbranded system.
Where the factory system falls short
- Fixed factory tuning, even with Harman Kardon — the collaboration covers speaker selection and voicing at the factory, but owners get no access to crossover, time alignment or per-channel gain.
- Non-Harman Kardon grades are built to a price — the base system on entry trims is engineered for acceptable background listening rather than serious volume or clarity.
- A tightly integrated factory amplifier — Subaru's Harman Kardon systems route through a dedicated factory amp module, making a naive aftermarket "rip and replace" install considerably more complicated than it used to be.
- Factory speaker locations are a compromise — door and dash positions are dictated by styling and NVH requirements, so even genuine Harman Kardon driver hardware is working against less-than-ideal mounting.
What a genuine Subaru upgrade path looks like
The right approach leaves the factory head unit, infotainment screen and Harman Kardon badging (where fitted) completely intact. A plug-and-play DSP amplifier — genuine HELIX or MATCH hardware, such as a HELIX AMPLIFY 206 DSP — wires into the factory harness, tapping the existing speaker-level signal with no cutting or soldering required. See the full range of DSP amplifiers this kind of upgrade is built around. Loaded with a custom tune for the vehicle, it gives independent control over gain, crossover points and time alignment per channel, plus considerably more clean power than the factory amplifier can deliver, whether your Subaru started with the base system or Harman Kardon.
From there, the natural next step is a plug-and-play component speaker upgrade fitted into the factory door locations, paired with a compact bench-box subwoofer in the boot for cars — like Forester and Crosstrek — that lean more on midbass drivers than a dedicated sub. Every factory-branded element — steering wheel audio controls, infotainment, microphone, EyeSight camera integration — keeps working exactly as before, and the whole install is fully reversible.
Why HELIX and MATCH DSP amps are the right tool for this
HELIX and MATCH are part of the Audiotec Fischer group alongside BRAX, and all three brands are German-engineered specifically to integrate with a car's existing factory system rather than rip it out and start again — the same approach already applied to Ford, Audi and Nissan upgrade packages live on the site. That matters even more on a Harman Kardon-equipped Subaru, where the factory hardware is already genuinely good; a DSP-based upgrade is about unlocking what it's capable of through proper tuning and added power, not replacing it.
The three stages in detail
Stage 1 — Amplify ($1,650)
A plug-and-play HELIX AMPLIFY 206 DSP amplifier, tapped into your Subaru's factory harness whether you've got the base system or Harman Kardon. Every factory speaker, feature and connection stays exactly as it was, including EyeSight camera integration — you're simply feeding the system far more clean power and better crossover points than the factory amp ever had. This is the foundation every later stage builds on.
- HELIX AMPLIFY 206 DSP amplifier — 6-channel bridgeable, 8-channel DSP
- Subaru-specific plug-and-play harness (standard and Harman Kardon-equipped models)
- Full retention of every factory feature
Stage 2 — Add Bass ($2,345)
Builds directly on Stage 1 by adding a dedicated bench-box subwoofer — particularly worthwhile on Forester and Crosstrek variants that lean more on midbass drivers than a true dedicated sub.
- Everything in Stage 1
- HELIX IK ES10.1-DVC2 — 10" bench-box subwoofer
Stage 3 — Full Speaker Replacement ($3,565)
Builds on Stages 1 & 2 with a full plug-and-play HELIX Ci3 component speaker upgrade engineered for your Subaru's factory mounting locations — the end-game before full custom fabrication.
- Everything in Stages 1 & 2
- Full HELIX Ci3 plug-and-play component speaker set
Why buy your package from Integrated Audio
- Genuine Audiotec Fischer hardware. Every HELIX and MATCH DSP amplifier we sell is genuine ATF product, backed by manufacturer warranty — not a generic universal kit.
- Doesn't touch your factory warranty. Our plug-and-play harnesses connect through your car's existing wiring with no permanent modification, so upgrading doesn't void your factory warranty — and the install is fully reversible if you ever need to return to standard.
- Self-install friendly, or we'll point you to someone who can fit it. Full install guides and trim removal tools are included with every package. Prefer not to DIY? We offer professional installation in the Sydney Metro area and can connect you with trusted installer partners elsewhere in Australia.
- Built by a Certified International EMMA Head Judge. Integrated Audio is run by Pete, who judges car audio Sound Quality installs at an international level — every package is engineered to the same standard used to judge competition-grade systems.
Frequently asked questions
Does this work with my Subaru's Harman Kardon system?
Yes — the package integrates with both the standard system and Harman Kardon-equipped Subaru models (Forester, Outback, Legacy, Impreza, Crosstrek, WRX).
Will this void my factory warranty?
No. Our plug-and-play upgrades connect through your vehicle's existing wiring and don't require permanent modification to factory components, and the install is fully reversible. Genuine ATF products carry their own manufacturer warranty.
Do I need experience or special tools to install this myself?
Not for our plug-and-play packages — most Stage 1 installs take 1-2 hours with basic hand tools and no prior experience, Stage 2 (adding a subwoofer) around 2-3 hours, and Stage 3 (full speaker replacement) 3-5 hours. Trim removal tools are included with every package where trim needs to come off, along with full install guides and support.
Can I start with Stage 1 and add a subwoofer or speakers later?
Yes — Stage 2 and Stage 3 are built to add onto Stage 1's amplifier rather than replace it. If you've already got Stage 1 and want to step up later, get in touch and we'll make sure you're only paying for what's new.
Does my package come with a custom tune already loaded?
Not currently — no Integrated Audio package ships with a pre-loaded custom acoustic tune today. Every DSP amp we sell is tunable in the official Audiotec Fischer PC Tool, and our free DSP Tuning Guide (paired with the AMI Tuning Kit) walks you through calibrating it to your own car in under an hour.
Integrated Audio now has a dedicated 3-stage upgrade path for Subaru, live and ready to order: Stage 1 — Amplify, Stage 2 — Add Bass and Stage 3 — Full Speaker Replacement. Not sure which stage suits your Subaru? Get in touch and we'll help you pick the right level.