How to improve audio in 996 with Bose speakers

Hi everyone, I bought my first Porsche last week a 996 mark II convertible with beige interior. While the car performs like a dream, the audio system really underperforms The car has a PCM 2.0 radio and has Bose door speakers. What I notice is that the midrange is almost absent, the highs are painful, and the lows are not actually very low. Also the volume cannot be turned up high. I've done some researching and I have unfortunately not found a definitive answer on how to diagnose and upgrade the audio. I know there are options out there to completely switch door panels, but they are very expensive (and not beige). Questions I have are: - Would changing only the speakers have a significant effect? If so, which ones are recommended? - Should I install an amp? And how do I know if there is an amp in the car already? - Do I need to change the PCM 2.0 system, and if so, will I lose certain functionalities? - What is the most cost effective way to get the most bang for my buck? NB: I'm located in Europe, therefore some brands or models may not be available here (e.g. SPS-410). Thank you for your thoughts! Robin

Does anyone have experience with this?

I've got a 996 Turbo with PCM2.0, MOST, and Bose. I find the audio is great! I'm deaf in one ear and significant hearing loss in the other. People with normal hearing find that it's terrible and there isn't much that can be done short of replacing it all. The PCM 2.0 talks to the amp by optical, the amp is not very good, there's no alternative to the amp that works with the PCM 2.0, and the speakers aren't good either. I suppose that be replacing the speakers you could make a start on it. Twenty year old speakers have probably degraded anyway.

Thanks for your response, I thought it was very funny . I could definitely try changing some speakers, although I'm unsure which ones fit and sound well, and have the correct impedance. I tried searching for 1 ohm subs, but to no result. After upgrading the speakers, I could always still switch the standard amp and the PCM 2.0 for a new amp and double DIN radio, right? Again the question would be, which one integrates with the Porsche (butons, computer, etc.).

Turn the radio off and listen to the sweet sound of that engine! Oh, and "drive it like you stole it!"

I replaced my head unit but haven't tackled the speakers yet. Also, I don't have the Bose system. Here's what I do know: -The sound on mine isn't great either but now that I have CarPlay, I'm OK for now. -If you have an amp, it will be mounted in the frunk -CAI is a good company to go to for information about Porsche audio. They're in the US but they still have great information -Changing the speakers is the usually the best way to improve the sound quality -On mine (non-Bose with amp) the door speakers serve as a low range. Sort of a mini subwoofer. I think the amp serves as a crossover for this See if anything in this thread helps: https://rennlist.com/forums/996-foru...or-2020-a.html

Hello I upgraded the radio to Kenwood DMX706S DMX706S | eXcelon | Car Entertainment | KENWOOD USA I also upgraded the amp to Knewood KAC-M3001 KAC-M3001 | Amplifiers | CAR ENTERTAINMENT | KENWOOD Canada Did not change any speakers and I am very happy. PM for info

PCCM Plus!

Call this guy, his name is Rod. CAI-Store.com

Changing speakers helps, but what really puts it over the edge (and not just for volume) is an amplifier.

Thank you all for your responses! What I'm reading is different things though, the speakers make the difference, or the amp does. I'm still unsure where to start. Although I can try and call CAI. What would be the advantages of the Kenwood system as opposed to the PCCM Plus system? And are changing both the amp and the radio at the same time indeed required?

I worked my way through college installing car stereos. Every bose system I ever saw used 0.5 ohm speakers making replacements incompatible. Sure they�d work, but the amp wouldn�t have enough power to drive them. Replacing just the amp was also a bad idea because of the low resistance speakers. We always replaced the entire system. Old saying goes as �no highs no lows, must be Bose�.

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Okay, and would replacing the speakers and amp make sense, while leaving the PCM 2.0 system in place?

When I owned my 996, I replaced the entire system. I installed a Kenwood head unit with a Focal amp and speakers. The speakers are the weakest link in the system. They’re crap.

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Does replacing the radio have an added effect? If one replaces the whole system, can the cabling be reused?

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Wow... lots of twists and turns in this thread. First of all, I'm not going to hammer Bose as a company. Most of the criticisms in my time have been from people that are in competition with Bose either through aftermarket install business, retail, or manufacturing. Quite honestly, Bose does offer some nice sounding modern systems in cars today but don't expect your 20-year old Bose speakers or other components to perform like it did when it rolled off the assembly line. More than likely, the paper cones of each of the drivers have deteriorated to the point where the speakers produce distortion especially the lower bass range. The next problem is the Bose amplifier. Since Porsche chooses to locate their radio amplifiers in the frunk area, they are not in a moisture-controlled area of the car and can prematurely fail or perform poorly as they age. Therefore, the amps tend to fail quicker than say manufacturers that put amplifiers inside the car's cabin. What you do at the point all depends on your comfort and budget level. Personally, if you want to retain the factory look and sound, then you need to stick with OEM type drivers and components. This will also retain the value when you got to sell the car. I strongly recommend NOT cutting any wires if you chose to install an aftermarket radio system. Now, if you're trying to make slight improvements to the sound problem, then you need to start replacing the speakers in the car. Again, I recommend putting the exact Bose speakers because the tuning of the driver, plus the impedance will match with the amplifier's output. Once you replace all the aging Bose speakers, then closely listen to the quality at different volumes. Ask yourself, has the sound improved, or is it about the same. The PCM2 should produce a clean digital sound that's still on par with modern car systems. If you're still getting distortion with the replacement speakers, then you need to look at replacing the car's Bose amplifier and sound processer. That should get you back to a base line factory system. If you want to improve functionality (i.e. BlueTooth connectivity) and make the car completely modern, then install Porsche's new PCCM+ Apply Carplay system. Remember, the PCM2 is a MOST based system that is integrated with the car's ECU by fiber optics. As others have mentioned, if you want to go aftermarket, its probably better to change out the entire system. But I wouldn't advise it personally. I would recommend retaining as much factory components as possible, but improving the head unit by going with the Porsche PCCM+. The PCCM+ is pretty much plug-and-play with MOST based systems. Most of the problems have been with making the PCCM+ work with older analogy Porsche systems. I've sold many cars, including two Porsches in the last 5 years, and Porsche buyers by far the pickiest when choosing their next Porsche. Most prefer an unmolested and unmodified car when it comes to Porsches. I know we don't like the thought of having to sell our cars, bu the reality is in 2-3 years, you might want something different. Cheers!

Hi b3freak, Thank you for your elaborate answer I agree with you when it comes to retaining factory standards as much as possible, visibly that is. Now I don't think replacing the PCM 2.0 radio for a PCCM+ radio would have a large effect, since it is a Porsche part specifically meant for the 996. I would however be cautious with trying to install a Kenwood radio for instance. Your suggestion would be to replace the current speakers for the same factory speakers (Bose). I've searched, and they do seem available second hand. The issue I have though is that it doesn't exactly feel 'smart', I would be buying and installing the exact same parts, while not knowing if they are going to be better or worse than what I already have. Would replacing the speakers plus the amp, but not the PCM 2.0 radio be possible? This would not visibly alter the car, but would potentially increase the audio quality a lot. I just don't know whether the PCM 2.0 system would work with other amps, if the cabling would support it, and whether there could be issues with the ECU. I see two scenario's that I would like to hear your opinion about : 1. Replace amp and all speakers, leaving the car optically intact. Would this work with the PCM 2.0 radio? 2. Replace amp and all speakers, and replacing the radio for the PCCM+. Would this work, and what would be the advantage (the PCCM+ is pretty expensive)? Thanks!

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That would be a good start regardless if you choose to upgrade the head unit to the new Porsche PCCM+. Personally, I'd start with new Bose speakers in the dash, door, and rear. Do you have the sub behind the rear seat or footwell? Remember, the speakers are usually the weakest link in the chain and that's were I'd start before replacing the Bose amplifier. A brand new one from Porsche is crazy expensive. If you purchase used speakers, just keep in mind, you may NOT solve the problem because you're just replacing aging speakers with.... more aging speakers. If you put aftermarket speakers in the car, you'll find it hard to match impedance since Bose is known to integrate low impedance drivers in their systems. The standard for aftermarket is 4 ohm. Many of the Bose speakers run at 2 ohm or even lower and are component type, NOT coaxial. This is the best option, but NOT the least expensive. You could easily have $4,000 - $5,000 in this level of upgrade. The PCCM+ can be purchased for $1300, but if you add the cost of replacement of all Bose speakers and amp, it will more than double the cost. Go to Porsche parts online and you'll see. Personally, I don't like throwing money at a project that's not needed. I would start with the speakers, then work to the amp, and then lastly, the head unit.

I think I should have been clearer in writing down these scenario's: I meant to change the Bose speakers and amp for aftermarket speakers and a third party amp. Would that work with the cabling and the PCM 2.0 system? I have a midrange and tweeter combination front and rear, so 4 sets (8 speakers in total) and Bose door speakers (subs) in the front.

The PCM 2.0 only works with the Bose amp. There is a possibility that another MOST-enabled amp could be used. I have no idea if this would work, and I have not tried it. This is the disadvantage of the PCM 2.0/MOST/Bose system: it only works as a system and upgrading one part is essentially impossible. None of the wiring is even useful to an aftermarket system. The only known upgrade is to the PCCM+ head unit, which of course does nothing to address the amp/speaker issue. If you haven't looked yet, search out MOST optical on Wikipedia for an idea on how it all works.

Okay, so basically the answer is, the ONLY way to improve the audio is to replace every single component, including the cabling. And it makes no sense to install the PCCM+ system, since it doesn't support a different amp either? Are there amps that support MOST other than the Bose one? And would new cables be needed from the amp to the speakers then? The only wikipedia link I found is this: https://en.m.wikipedia.org/wiki/MOST_Bus but it doesn't really tell me much.

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I am telling you the PCCM + is the way to go. The sound quality is amazing in an original MOST system with the stock Bose amp and speakers for just under $1300. Is�s fully integrated with the 996 electronics. I went from a CDR23 to the PCCM + and now I also have clock and navigation control from the PCCM + to the instrument cluster to boot!

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So has your audio quality improved significantly? And was it bad before?

It would seem like adding this box box between the PCM radio and an aftermarket amp could be a solution. No idea if this has been tried before though.

[QUOTE=robinmg;17104690]So has your audio quality improved significantly? And was it bad before?[/QUOTE

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The sound quality has absolutely improved both in quality and power. It�s like a whole different sound system now.

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Those boxes only support left/right. They don't have front/back fade capabilities.

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So potentially I could upgrade with aftermarket speakers + aftermarket amp + "the box", with losing fading as a side effect. Sounds worth contemplating!

Okay so I opened my frunk, and guess what... There is no amp. The place where it's supposed to be is empty, with a few loose cables hanging out. How is it that I'm even able to get any sound out this way? I'm super confused now!

The main amp is behind the carpet on the passenger's side. You need to remove the carpet to see it. The subwoofer amp is under the removable carpet, next to the spare tire. The CD changer sits on the shelf on the right-hand side, in plain view.

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Thanks. Let me take a better look tomorrow. I'll take some photos as well. It's almost midnight now.

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There were a lot of configurations of these systems within the 996 generation, but it appears you have the Bose amplifier, but missing the CD changer. Not a big loss especially if you plan to upgrade to the new PCCM+ with BlueTooth.

Actually, there is a CD changer built in the dashboard. I wonder what was in the place of this 'gap'.

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Actually, those MOST fiber optic conversion boxes are designed to install aftermarket radios while retaining the OEM factory amplifier. You'll notice on the conversion box there are two RCA connections. Those plug into the pre-amp outputs of aftermarket radios. The other lines are for 12V switched/constant power and ground.

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Oops, so the other way around wouldn't work?

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Nope! Those MOST based boxes are not bidirectional. That box converts the analog "pre-amp" outputs from an aftermarket radio to a digital signal that the factory OEM amplifier will accept. It's very risky trying these boxes. Many have complained of unwanted ground loop hum coming from the speakers. IMHO, you're better off upgrading to the Porsche PCCM+ which supports the MOST transport stream. Also, checking the speakers for performance and replacing the defective ones would be a huge improvement. If you go aftermarket, it will involve a lot of work, basically replacing the whole system to do it right. Just my opinion. I've done it many times before we had the option of the Porsche PCCM+.

I guess it just seems odd to me that upgrading the radio would have a significant effect on the sound. Maybe it's true though!

Your car used to have the CD changer, the bracket and wiring and MOST cable is on the right-hand side. The CD slot in the PCM 2.0 is really for the navigation disk, and it's a one disk system. You can take the nav disk out and play CD with it, this makes the nav even more useless than it already is. Perhaps there's something like the Mr. 12 Volt bluetooth input installed? I have one of these. It replaces the CD changer with a bluetooth/aux/SD card interface.

Well there is a cd changer, directly below the PCM radio?

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Really? This I have never seen. I haven't actually used the CD changer in any of my cars in about 8 or 10 years, though.

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I'll take another photo tomorrow!

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Please post a picture of your radio and the unit you describe. The older analog PCM1 had a separate data-disc player that was designed for playback of navigation only discs, but the PCM2 eliminated the need for a separate player unit. Of course, the new PCCM+ doesn't need any navigation discs, but is imported by SD cards. However, most people are going to use Google maps via Apply Carplay instead of the Porsche proprietary nav system.

As long as you can get a line level out of the pcm system then yes. We kept a few head units in the past, most were okay but never anything great. More customer preference to keep the stock look.

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I can't really tell you anything more than others have already contributed. I was looking for a modern head unit with navigation, etc. I decided early in the process to replace the entire system, including the wiring. It was expensive, but I was very happy with the results.

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So I actually found two links that might be useful. This device converts the MOST signal into an analog signal, while this device converts the MOST signal into a Toslink signal. Both could theoretically be used in order to install an aftermarket amp. This subverts the impedance problem of the speakers, although the cabling between the speakers and the amp would still be an issue.

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As you can see in the image, the PCM2 has is own CD slot (Green Arrow) for playing music. This is also used to update navigation data. The lower unit (Red arrow) you thought was a CD changer is basically just a CD holder.

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LOL I hadn't actually tried it yet. But yes, in the dashboard cupboard there is a line in as well, that was put there by someone. So the previous owner removed the cd changer and added a device that has line-in and USB (no bluetooth, sadly). But in effect, this is off-topic. I'm interested in sound quality really.

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As I mentioned before, it all boils down to your comfort and budget level for a project like this. You must determine what you're trying to solve ultimately. Is it a quality sound issue or functionality or both? Porsche has made it very clear in their literature, that their sports cars like the 911 are NOT the best suited for pure sound reproduction. Performance is their top priority and that means you're not going to get the acoustical sound treatment like you would expect in a luxury SUV for example. The engines in these cars will drown out any sound system and create overtones that make it impossible to get "clean" sound reproduction even from the best automotive sound system. BMW and others are even using noise-cancelling technology to help improve the cabin's noise problem, but it's never going to be as good as sitting in an acoustically engineered audio screening room.

Yes. It's definitely a sound upgrade I'm looking for. Doesn't have to be studio quality at all. The sound quality is BAD right now. Lacking mids, painful highs and almost inaudible lows. Also volume is a thing. And to top it off, I'd like to fix this while retaining a Porsche radio. So either the PCM radio or PCCM+. Basically the one that offers the most quality for price.