[charlesH]

FWIW

I was considering whether a speaker up grade (back seat woofers and / or a luggage compartment sub-woofer) was worth it.

I decided to take some measurements regarding the bass/mid bass frequency response of the entry level stock speakers (no sub-woofer).

Using an A weighted sound pressure meter and warbled test tones I obtained the following results:

Hz, db

200, -2
160, +2
125, +2
100, +2
80, +2
63, +2
50, 0
40, -4
32, -12

I was pleasantly surprised (shocked) as to how flat and extended the low frequency response was (I expected a peak around 120 Hz and a sharp roll-off below ~80Hz). Flat to 50Hz and real usable sound down to 40Hz. Based on my musical tastes (classical, jazz, and light rock), I have decided the stock speakers are pretty darn good and I wouldn't get that much benefit trying to get bass extension below 40Hz.

 

[RedWouldForrest]

Perhaps you were shocked because the test results did not line up with your expectations.


Sound meters do not necessarily equate to the human ear. Let your ears decide for themselves.

 

[charlesH]

Perhaps you were shocked because the test results did not line up with your expectations.


Sound meters do not necessarily equate to the human ear. Let your ears decide for themselves.

Exactly, I did not expect the stock speakers to perform so well.

"A " weighted is designed to match the human ears perception of sound level. Instruments don't lie.

 

[yticolev]

Instruments may or may not lie, but human methodology is fallible. Human sound perception can be quite incredible so if you are perceiving a difference, your methodology may need changing. Did you run your tests with your mic at multiple points, including at your ears? Did you try this while driving with that different frequency noise floor? (which also means you will be stressing your amps at a higher SPL level) Did you do this with both your prior car and this one to correlate measured results to your own sonic experience? Sound engineering is whole lot more complex than simply having a flat response at one mic position, otherwise design of speakers and placement would be simple. Mobile environments are much more difficult that home environments by at least an order of magnitude.

 

[charlesH]

Instruments may or may not lie, but human methodology is fallible. Human sound perception can be quite incredible so if you are perceiving a difference, your methodology may need changing. Did you run your tests with your mic at multiple points, including at your ears? Did you try this while driving with that different frequency noise floor? (which also means you will be stressing your amps at a higher SPL level) Did you do this with both your prior car and this one to correlate measured results to your own sonic experience? Sound engineering is whole lot more complex than simply having a flat response at one mic position, otherwise design of speakers and placement would be simple. Mobile environments are much more difficult that home environments by at least an order of magnitude.

I was only interested in the bass response (e.g. 20-200Hz) of the stock speakers at moderate SPL (sound pressure level). One might check harmonic distortion vs high SPL is one wants earth shattering sound levels.

v=frequency x wavelength so wavelength = speed of sound / frequency. Thus the wave length at 100 Hz is ~ 11 ft. Combined with using warble tones (to avoid standing waves) bass response should be pretty uniform throughout the interior of the car. This was confirmed by checking SPL at various points inside the car.

I did first compare the Niro bass response subjectively with a high quality speaker in a sealed enclosure (60 Hz low end). I tuned the car and the speaker amp to the same FM ratio station and noted the difference. To my ears, the car bass response was at least as good as the enclosed speaker. This surprised me and thus I decided to do actual measurements as previously reported.

 

[CoffeeNiro]

Has anyone with the basic speaker system done an upgrade? I am not any kind of audiophile like the other posters here who are mighty technical to the extent my brain has glazed over, but I did prefer the Harmon-Kardon system in the touring model I test drove, yet didn't buy due to road noise. If anyone has upgraded, I'd love to hear about what you did.