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ASL on 2007 adds too much bass.

Discussion in 'Gen 2 Prius Audio and Electronics' started by klevitsky, Nov 23, 2006.

  1. klevitsky

    klevitsky Junior Member

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    Whenever the ASL (auto sound leveling) is ON (either low, medium or high setting), it adds disproportionately more BASS at highway speeds. If I disable the ASL and simply turn the volume up to the same level, the audio sound fine (all frequencies are amplified equally). It is so bad that I cannot use the ASL at all, at speed the audio has way too much bass, to the point where my outside mirrors are vibrating slightly, yet I am still struggling to hear the lyrics. A quick check of the manual tells me that the ASL adjusts the volume AND tone of the sound based on its analysis of the background noise. Does it really have an ambient noise meter somewhere? Seems unlikely. But more importantly, has anyone else encountered this issue and if so, how did you resolve it?

    BTW, I have a 2007 PKG #2. Stock audio system with the AUX-in, not the upgraded JBL.
     
  2. klevitsky

    klevitsky Junior Member

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    Am I the only one that has this problem with the ASL feature? I guess I'll have to pay my dealer a visit.
     
  3. TonyM

    TonyM Junior Member

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    <div class='quotetop'>QUOTE(klevitsky @ Nov 26 2006, 10:00 AM) [snapback]354203[/snapback]</div>
    I wish I had that problem with my JBL system in my '07. The JBL system is about the weakest link for me in my Prius.

    Good luck getting it worked out.
     
  4. black_metal_525

    black_metal_525 New Member

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    Klevitsky, I know exactly what you're talking about. I have a 2006, and I never have the ASL turned on because the increase in bass response is obnoxious, quite frankly. I'm not aware of an ambient noise meter in the Prius, but perhaps another member may have some more insight into that. I have noticed that the ASL increases incrementally at certain speeds, though I don't recall exactly which points those were at the moment. In any case, I find the bass increase in the ASL to be a useless feature for most genres of music, at least those that I listen to, so my resolution to the matter is to just leave it off and adjust the volume myself.
     
  5. klevitsky

    klevitsky Junior Member

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    Yeah, we've pretty much settled on this solution also. If I have to bring the car in for other warranty service, I will definitely mention it to the tech, but I don't think they will do anything about it so it's not worth a separate trip to the dealer at this point. So far I've accumulated a small list of things to look at:

    1. Radio reception is significantly worse than my Avalon, but I've seen posts that say the same, so probably will get a brush off from the dealer.

    2. Brake pedal makes a click on the down stroke (like a relay) and an annoying springy-vibrating noise on the way up (about 50% of the time). Almost like a pump pressurizing the system, but it definitely originates from under the dash. Waiting to see if it's part of the break in/wear in process (only ~2000 miles on the ODO).

    3. The ASL BASS abnormality.
     
  6. eagle33199

    eagle33199 Platinum Member

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    Location:
    Minnesota
    Vehicle:
    2015 Prius v wagon
    Model:
    Two
    i was recently reading reviews on sound canceling headphones, and think some of the things noticed may apply here, FWIW.

    When listening to the headphones at home or in the store, the balance was all sorts of off - essentially the base was too loud, the mids and highs were too soft and sounded a little muddled... however, when they were taking into their intended environment (and airplane), they sounded great - the guy was using the star system, and gave them a 3/10 at home, but a 9/10 in the airplane. Yes, the difference was that huge.

    He suspects that, even with the sound canceling features, the increased low frequency hum from the engines and such effects the sound, making those particular headphones awesome in that environment, but horrible in his relatively quiet home environment.

    Now, for how this relates to the Prius... I think the engineers were going for a similar type idea - as the low frequency noise from the road and wind increases on the highway, the bass needs to be increased to compensate. Good idea, but i think it's pretty clear they didn't exactly get everything perfect...