2016 Forester Speaker Upgrade
In November 2016 I upgraded the speakers in my Forester from the stock speakers to the upgrade speakers sold by Subaru. Before doing so I could find only anecdotal evidence of the value of such an upgrade. So as a service to others in my situation, I documented the upgrade with objective data. Later, I also provide my subjective opinion, as an audio engineer with 27 years experience.
Components
The speaker upgrade consists of two part numbers, a tweeter package and a 4 door speaker upgrade. There is no sub woofer option for this model year.Tweeter Kit: Part Number: H631SFJ100 Subaru Website Installation Instructions
Speaker Kit: Part Number: H631SSG000 Subaru Website Installation Instructions
Price
The price for both parts is currently on the Subaru website is about $370, not including installation. They can be found on Amazon currently for a shipped price under $300. I did not inquire about dealer installation, though I expect it would be a couple hundred dollars. Having read the installation instructions and being fairly handy, I knew I could do it myself.If you don't have a set of car panel removing tools, they are very useful in installation and can be had on Amazon for around $7.
Tweeters
Here a stock and upgrade tweeter are shown next to each other. I did not weigh the two tweeters since weight is often not that important with tweeters. The upgrade actual felt lighter. The stock tweeters are paper coned and have a sheer nylon cover (difficult to see in picture). The upgrade tweeters have a metal grill. |
| Top view: stock on left, upgrade on right. |
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| Side view: upgrade on left, stock on right. |
Rear Door Speakers
A stock and upgrade rear door speakers are shown next to each other. They are the are 6.5" form factor. The stock weighed 8.2 ounces. The upgrade speaker weighed a whopping 50.7 ounces.The stock speakers have a whizzer cone, a small paper cone glued on to the main cone to provide better high frequency response. The upgrade speakers have a separate coaxial tweeter with a passive crossover. The magnet on the upgraded speakers is obviously much larger. This typically results in deeper and louder response.
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| Top view: upgrade on left, old on right. |
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| Side view: stock on left, upgrade on right. |
Rear door speaker installation is a little trickier than the tweeters. You have to remove the door panels which is always a little scary to do on a new vehicle. But I had done it on other cars and knew what to expect. As usual, the panel clips sometime stick in the door and have to be removed and put back on the removed panel. Keep an eye out for the foam washers that if you don't keep track of, can get lost. I actually forgot to reconnect the window actuator when I put one of the panels back on and had to do it again.
Front Door Speakers
A stock and upgrade front door speakers are shown next to each other. They are the 6 x 9 form factor. The stock weighed 12.5 ounces. The upgrade speaker weighed 47.5 ounces, which is actually less than the upgrade rear door speaker despite having a larger cone and mounting ring. The stock front door speakers are identical to the rear door speakers except they have a modified plastic surround that allows them to fit in the larger 6x9 hole.The stock speakers have a whizzer cone, a small paper cone glued on to the main cone to provide better high frequency response. The upgrade speakers have a separate coaxial tweeter with a passive crossover. The magnet on the upgraded speakers is obviously much larger. This typically results in deeper and louder response.
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| Top view: upgrade on left, stock on right. |
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| Side view: stock on left, upgrade on right. |
Performance
I used the AudioTools iPhone application by StudioSix to test the speaker performance before and after the upgrade. I used both the FFT and RTA tools, but found the RTA tools more useful.For those not familiar with actual speaker frequency response graphs, they are a little scary in the roughness of the response curve, unlike audio electronics gear. Even the most flat responding speakers look like the Himalayan mountain range. The FFT curve shows a whole lot more variability and detail at mid and high frequencies, but very little at low frequencies due to how the data is generated. But all that data can hide the general trends that are going on.
A 1/3 octave RTA gives 30 measurement points, evenly spaced on a logarithmic scale, in the audible spectrum. That provides some generalization so overall trends can be measured.
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| RTA comparison of stock (old) and upgrade (new) speaker frequency responses. |
Response Interpretation
It can be seen that the low frequency response is improved with the most improvement coming in the deepest response. Mid bass boomy-ness is reduced and the overall response is flatter. However, the improvement is on average about 2 dB. With the threshold of hearing a change being at about 1 dB, the improvement is not dramatic, though the improved depth and flatness should be noticeable.SPL Interpretation
Also tested is the overall SPL or loudness of the system. Here a C weighting was applied which most accurately matches human perception at normal listening levels. C weighting puts less emphasis on extreme frequencies, meaning they must have a larger change to result in a changed SPL. The stock speaker actually measure slightly louder at 84.3 dBC than the upgrade at 83.8 dBC, but within the accuracy of the test. This is a result of the increased bass response not offsetting the reduction in the mid treble frequencies around 1 KHz to 4 KHz.Test Conditions
The conditions of the test should be noted for comparison. The head unit was set at a volume setting of 50, near the top of the scale, but avoiding the very top in case there was excessive distortion at those levels. The input came from a USB connection to an iPhone 5. The AudioTools App was generating a SMPTE pink noise signal and being measured using the internal mic. The microphone's response is compensated by the AudioTools software so that it is essentially flat. The software is aware of mic responses of all devices the App can run on.I wore hearing protection as the loud pink noise would have effected my ability to do listening tests for some time. I sat in the driver's seat as I would normally drive, except with the seat reclined more so that when I held the iPhone about a foot in front of my eyes, it would be a little forward of where my head normally is. I did not want to recline too much to not effect the sound coming from the rear speakers.
It should be noted that changing my foot position had a noticeable effect on response, so I endeavored to keep my feet in the same driving position for all tests.
Subjective Interpretation
I had read several anecdotal reviews which basically, on average, said that the upgrade speakers are a modest improvement. Though those reports may have tainted my opinion, I mostly agree. I did not read a lot of detail on why they came to that conclusion.Who am I to Decide
I am a middle-aged man with declining high frequency hearing. I increasingly find excessively loud or distorted sound physically painful and suffer Tinnitus from even less exposure to shrill sounds. It is important to me when I listen to music that I get the maximum enjoyment with the least pain and long term damage.This hearing damage I suffer came as a result of being a life long music appreciator and audio engineer. My audio engineering is as a software consultant familiar with audio processes and terminology as opposed to someone who listens for a living.
About 1/3 of my car audio experience is talking on the phone through Bluetooth. 1/3 is listening to my extensive MP3 collection on my iPhone, either through USB, or Bluetooth if I am in a hurry. About 1/3 is listening to FM, HD Radio or occasionally Sirius/XM.
If I had unlimited money, I never would not have bought a Subaru Forester, instead opting for a silent electric luxury car which already had a finely tuned audio system. But I live in reality, and the Subaru Forester was the car for me. This is despite many shortcomings in the audio system.
The Car
From test driving the car, I knew that the audio system was very basic, mediocre sounding and not particularly ergonomic. It is the second Forester I have owned. The touch screen interface I find requires too much attention to operate. It is difficult to get to screens to control the sound (there are no bass and treble controls at all). A Graphic EQ is available, but the bands are too wide and not focused in the areas that need the most adjustment. An always available bass, mid, treble control, as my previous Forester had, would have been far superior to what is offered.So after 6 months driving it, and thinking I would likely be driving it for many years, I decided it was worth making some modest improvements. The $300 and 3-4 Saturday afternoon hours I put into it were not difficult for me to do.
The Results
Phone calls to my family now have a slight added intelligibility which means I am asking them to repeat things a little less. I suppose this is because of added clarity in the vocal range due to a flatter response and less distortion in high frequencies.Listening to music on the iPhone, either through USB or Bluetooth, is most improved. The bass is more 'open' and natural, a little deeper bass, but hard to hear the difference. I find vocal content less painful, and imaging is noticeably improved. USB, of course, sounds better than Bluetooth.
FM/sat is improved the least. HD radio does have slightly better bass and is slightly less painful. Standard FM/Sat is pretty much the same. This is probably because these media are highly compressed and frequency limited. If this is what you listen to, I wouldn't bother.
In all cases, the most lacking thing about the audio system post-upgrade is the lack of truly deep bass and the deficiencies of controlling the audio with the head unit. Installing an after-market sub woofer is definitely called for. But I have apprehension about theft, loss of cargo space and damage to the car caused by poor installation. This needs further consideration. Replacing the head unit is not going to happen due to the level of integration the current one has with the car for other features, particularly phone and steering controls.
For me this was a good and worthwhile change. But, I would caution anyone with high expectations for improvement from this route.
