Replace JBL speakers in 2011 Package 5?

I am also looking for improvements to the sound of my JBL with NAV. One thing I did recently was add sound deadening material inside the doors. It is a dynamat type material. It made the bass sound much cleaner and requires less bass than before. Now I want to improve the high end and am looking for some replacement tweeters.

 

I have a 2010 Package 5 that came with the 8 speaker JBL/NAV system, which is probably very similar if not identical to the 2011. I have replaced or bypassed almost every audio component on the darn thing, and there are many things I would do differently if I had it to do over again. I've taken a lot of pictures and I've been meaning to write up a build log to share my experiences, but I still have a piece or two to install before I put down the wire crimpers. Here’s a brief list of what I have installed:

• Alpine INA-W910 DVD Navigation head unit (plus backup camera, steering wheel control interface, and video lockout bypass units)
• JBL MS-8 Sound processor
• JL Audio XD600/6 front-stage amp
• JL component tweeters
• Hybrid Audio Technologies L3SE wideband midrange drivers
• Dayton Audio Reference Series 7†midbass drivers
• Boston Acoustics GTA-400m sub amp
• JL Audio “Flatwedge†8†ported subwoofer (soon to be replaced with a JL 10†sub in a custom fiberglass enclosure that fits in the right rear cubby over the 12v battery)
• Cascade audio sound dampening in the doors and floorpans

My impressions of the sound of the 8 speaker JBL NAV system: Overall very good sound quality, but the bass didn't go much below about 50hz and it had a harshness in the upper-midrange that the built in EQ would not tame. Also, I found the interface of the factory head unit to be absolutely terrible, both using the navigation and the iPod interface. (Radio reception was also abysmal, but I never listen to the radio.)


What you need to know about the 8 speaker system is that it is very much a “systemâ€; all the components are designed to work together, and there is no easy way to improve it replacing one component at a time. The heart of the system is a DSP/amp box under the front passenger seat which powers each of the eight speakers individually; each channel is time-aligned, equalized, and band-passed for the specific speaker it drives. This amp is designed for the OEM speakers which are 2ohm; it really does not have enough power to drive standard aftermarket 4ohm speakers. To make matters worse, the OEM speakers are designed to play frequency bands that are different than most aftermarket speakers: the front and rear woofers are mid-bass drivers and only play up to about 200hz, and the “squawker†mid-tweets play everything above that. For the 8 channel systems we have, it is almost impossible to find any replacement speakers that improve on the OEM speakers while still using the OEM DSP/amp.

If you are reasonably happy with the way the factory head unit operates, you might begin by replacing the OEM DSP/amp with a JBL MS-8 sound processor. It does a much better job of doing everything that the OEM box does, (time alignment, equalization, band pass filtering, and eight channels of amplification), but it is far more adjustable (e.g., 31 bands of equalization instead of 3), and it is compatible with any other additions and upgrades you might make later on, such as adding a sub or replacing speakers. It will fit nicely in place of the OEM unit, and pretty much all the wires you need are already there (power, ground, speaker connections -- see attached). The one thing I’m not sure about is the signal input coming from the headunit. The wiring diagrams show left and right audio (+ and -) coming in from the headunit, and this is almost certainly a line-level balanced audio, which the MS-8 can work with. I’m sure there is someone else on this forum who has installed an MS-8 with the OEM head unit and can confirm exactly how to do this.

Once you have the MS-8 to build on, the next step might be to add a subwoofer. You could use one of the powered all-in-one units or install a separate amp and sub. If you want bass that will rattle the pictures off the walls in people’s houses as you drive by, be sure to get a Class-D amp, because the Prius has the weakest 12v electrical system this side of the Atlantic. Fortunately, the battery is in the rear, so it simplifies the wiring considerably. By the way, it is possible to add a sub to the Prius factory system without the MS-8, but I tried it, and it sucked. Folks with the 6 channel systems can simply connect the sub amp’s speaker level inputs to their front or rear woofers and get a decent signal. Unfortunately, those of us who are “blessed†with the 8 channel systems aren’t so lucky. The bass being sent to our front woofers is rolled off significantly below 50hz, so you still get nothing below that. Connecting to the rear woofers sounds even worse.

I have replaced the front speakers on my system, and I can tell you that this is very difficult and probably not worth the trouble unless you really have a lot of time, money, and skill to invest. I am still working to figure out a permanent solution for mounting the midrange speakers in the dash. If I had it to do over again, I would probably just use a standard 6.5 component system and mount the woofers in the door and the tweeters (on separate MS-8 channels) in place of the factory squawkers. One thing to remember if your car is equipped with the “SOS†safety connect emergency system and you do want to replace the front speakers: The safety connect system is wired in line with the right front squawker, so if you want to be able to communicate with the call center in the event of a problem, you need to keep a speaker of some sort connected to this pair of wires.

Other disclaimers: Mine is a 2010 model, so yours may be different. Be sure to verify everything on techinfo.toyota.com before you start. Your mileage may vary. Your resale value may decline. Your significant other’s tolerance for car audio upgrades may expire before the project is complete. Most importantly: Nothing spoils a fun audio project like fouling up your airbag system, so DISCONNECT YOUR 12V BATTERY FOR 2 MINUTES BEFORE YOU DISCONNECT ANYTHING ELSE.

 

One thing I forgot to mention: The single biggest audio problem with the Package 5 cars is the astounding level of road noise. I did a lot of sound deadening and reduced the noise considerably, but it is still almost unbearable at times. I can't tell if the noise is radiating from the tires' contact with the road, or if the vibration is being transmitted mechanically through the tires> suspension>chassis. I still have to research this one, but once I wear out the first set of tires, I'm thinking of switching to 16" wheels and more cushy tires!

 

If MPG is not an issue, or much of one, I am going to the Michelin Primacy MXV4 when I get the new tires since the ride is very much quieter. Sidewall height is an issue with road isolation, so the 15" on my IV is good, but you probably don't want to come down that far. Also, tire inflation is an issue. I am sure you know all this, but the Primacy's are awesome for reducing road noise.