Porsche 987 Audio Upgrade - Things to know

I posted this on a different forum, thought it would be good to posted here to. I see this come up constantly, so here’s a complete explanation based on both data and real experience. I’ve personally done 30+ high-end car audio systems in my own cars and for others, and early in my career I worked in the mobile audio industry, selling high-end gear, tuning systems, and helping competitors in sound quality (SQ) setups. The Cayman is a fantastic platform for audio, but only if you understand how the factory system works. Summary : ASK door woofers are ~3 Ω, not 4 Ω → 4-ohm replacements receive less power ASK amp is 30 W RMS — not enough for high-end aftermarket speakers Factory EQ changes with volume → inconsistent tonality Factory crossovers use basic capacitors → mismatch with premium drivers Nothing is true drop-in, but nothing requires major surgery Cayman speakers: 8” midbass, 4” mids, 1” tweeters, ~3” center, 4” rear For real gains: 3-way front, upgraded amp, small sub, center disconnected Breaking this down: 1. The ASK door woofers are ~3 Ω, not 4 Ω (per several threads, I did not test mine when I removed them) This is one of the most misunderstood details. The lower door woofer in the 987.2 Cayman (Sound Package Plus / ASK system) is roughly 3 ohms. Not 4 ohms, not Bose’s 2 ohms. This is important because: Lower impedance = more wattage from the weak factory amp. Replacing a 3 Ω woofer with a 4 Ω aftermarket woofer = less power, less output. Aftermarket companies may sell a 3-ohm, never looked as universal is 2-ohm or 4-ohm. You can simulate with add a resistor. This is one of the biggest reasons people install Focal/Hertz drivers and get less performance, not more. Just dealt with this with my neighbor in a different make and model. He replaced with aftermarket speakers and thinks the sound is now worst than before. 2. Premium speakers need more power than the ASK amp can deliver The factory ASK amp is roughly 30 W RMS per channel per my research. Better than an aftermarket head unit, but still not great for aftermarket speakers. Most premium speakers need 60–80 W RMS to perform the way they were designed. That means: You cannot get Focal/Hertz/Audison performance out of 30 W RMS. The speaker will play, but it will never reach its potential. You’ll hear less midbass, lower volume, and reduced clarity. Underpowering does not damage a speaker, but it prevents it from performing. 3. Factory amps have fixed gain — you can’t tune them Here’s a key concept from high-end installs: > It’s always better to have more amplifier power than the speaker needs, and control it with the gain for clean headroom. But the ASK amp: Has fixed gain Cannot be tuned Cannot be matched to speaker sensitivity Cannot handle 2-ohm loads unless Bose Cannot deliver proper damping or control over upgraded drivers This makes speaker matching absolutely critical in factory systems. 4. Factory speakers use simple capacitors as crude crossovers See the pic in the link that was posted pre my response. The back side of the speaker, has a little black capacitor soldered in. This is the crude signal filter. High end aftermarket speakers do not have this and they typcially have large crossover that are the size of a 3x5 index card to a 5x7 card with multiple coils, capacitors, and switches. Or you have gone straight DSP and Straight Amp. That's another topic. The stock Cayman speakers have: Inline capacitors for the mids/tweeters No proper multi-order crossover Basic filtering dependent on speaker selection When you install aftermarket speakers: Their built-in crossovers may not match the ASK output The ASK amp may send full-range signal where it shouldn’t Tonality can shift dramatically Mids may sound honky or hollow Highs may become harsh The system is simply not designed for modern audiophile drivers. 5. Almost all factory systems uses dynamic EQ that changes with volume As you turn the volume up (or other system factors such as turning up you fan in you car), the system automatically: Reduces bass Boosts mids and highs Compresses peaks Limits distortion This keeps the factory amp from blowing up, but it also means the sound changes at every volume level. If you’re chasing more volume and clarity, or going after SQ, this becomes a major limitation. 6. No aftermarket speakers are truly “drop-in” In regards to stereo system, from direct manufactures, I do not believe there is a true plug-and-play replacement for the Cayman. There are aftermarket companies that buy speakers, build the plates, and then sell as no mod drop in. Aftermarket speakers are universal size. But, you don’t need extreme modifications. Expect: Light trimming Spacer rings Slight depth adjustments Reuse of factory grills Some creativity in mounting Just setting the right expectations so nobody is surprised. 7. Actual speaker sizes in the 987.2 Cayman Here’s the clean breakdown: Door midbass: 8 inch (woofer) Dash mids: 4 inch Tweeters: 1 inch Center: ~3 inch Rears: 4 inch These are the sizes to shop around. 8. Proper staging advice (SQ-based) Front stage: Full 3-way The Cayman’s cabin is naturally well suited for a 3-way front stage: 8” midbass in the doors 4” midrange in the doors 1” tweeters in the dash I did the following: 6.5” midbass in the doors 4” midrange in the doors 1.25” tweeters in the dash 4" coaxial in the rear 10" sealed sub 5 channel amp bridged to 3 channels This creates a true sound quality front stage when powered correctly. In regards to the Center speaker - pointless. If you upgrade the whole system: Disconnect the center unless you are doing DSP with proper 2-channel upmixing. The factory center muddies imaging and pulls staging downward. Rear speakers The rears in a Cayman are more like ambient surround fill. You can run them off deck power or leave them low. They don’t contribute much to staging. Subwoofer A proper system needs a sub, even a small one.The 8” door woofers are NOT subs, they’re midbass. A compact sub makes the system: Warmer Fuller More dynamic Less strained 9. So what should people actually do? You don’t need to replace everything. But you must match components. If keeping the factory ASK amp: Use 3–4 Ω speakers designed for low power Add proper crossovers Expect modest gains If you want real sound quality: Upgrade the amp to 60–100 W RMS per channel Use proper crossovers (or DSP) Upgrade the 3-way front Add a small sub Disable the center (unless DSP’d) This setup will outperform any factory premium system, Bose included.

For a minor correction, the center channel speaker is definitely not a 4. It's more like a 3, and I think it's actually closer to 2-1/2. But yes, it's useless. Simply unhook it when going aftermarket.

Thank you for the identification about the center channel. I adjusted the post. Regard

Do you know if this information also applies to the Bose system , or are they substantially different?

Drivers are the same sizes, but impedances are lower, 2 ohms. Also, the Bose amp 's input signal is fiber optic, not analog. So if you keep the Bose amp but want to change your head unit, you'll need a MOST interface box.

Quick question - how much of this applies to 987.1 's? I have a stock SP system that I'd love to upgrade but I see a bunch of conflicting information around upgrading it. This post though seems to do a good job of explaining the discrepancies I've seen.

Pretty much identical. Biggest difference is in the factory stereo and amp. The stereo in the .1 is even older with even less features, and the amp has a completely different pinout. Plus I'm pretty sure the amp is in the frunk in the .1, whereas it's under the passenger seat in the .2 Speaker sizes will all be the same though.