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Big audio system - adverse effects on economy?

Discussion in 'Gen 2 Prius Audio and Electronics' started by DAM0, Jul 31, 2014.

  1. DAM0

    DAM0 Junior Member

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    Hey guys, '06 prius from Australia here with base model Audio system, no nav, etc.

    What was the largest power consumption audio system you've seen in a prius? I'm thinking about installing some audio gear, but scared how much it will affect my fuel economy.

    To put it in perspective, I'm planning on installing:
    -Aftermarket double din head unit (either Nakamichi or Pioneer) - with nav, BT and all the other goodies
    -2000wrms @ 2ohm monoblock amp (~5kg/11lbs)
    -12" sub (~10kg/22lbs) in a ~10-15kg/22-33lbs heavy enclosure
    -Soundstream reference 920.4 4ch amp - 145wrms to each channel (~5kg/11lbs)
    -Morel Virtus front splits
    -Another set of aftermarket coaxial or dedicated midbass speakers in the rear doors
    -Another 12v battery (55Ah) to compliment the 12Ah stock battery (~20kg/44lbs)
    and I'm pretty sure by this stage I'll be needing some deadening in a few places.. so +10kg/22lbs for that and a few kgs/lbs of wiring

    By now I'm pretty sure you can see the issues with electrical demand and weight that I'll be facing. Has an install of this scale been done in a prius before?

    Does anyone know how much this would affect fuel economy?

    Thank you.
     
    #1 DAM0, Jul 31, 2014
    Last edited: Aug 1, 2014
  2. DAM0

    DAM0 Junior Member

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    Bump, anyone have any input on the electrical side of things?
     
  3. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    As I recall

    Given that 30 A is what the the inverter can charge the 12 volt system with and that the 12 battery is very small, anything over 400 Watts is just for the decals, not the sound. (1000 Watts RMS)
     
  4. valde3

    valde3 Senior Member

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    Weight is about the same as one passenger but it’s at the back so it may cause bad aerodynamics unless you do something to springs.
     
  5. DAM0

    DAM0 Junior Member

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    The weight shouldn't be a massive issue valde3, kind of like having someone sit in the back seat?

    I've heard that the standard charging system was something like 800w? (making that ~55-66A depending on voltage) In an effort to get around the super small standard battery I'm adding an optima to help share the load, yet add more load to the charging system :\

    Thanks very much for the replies guys!
     
  6. valde3

    valde3 Senior Member

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    Even if you play some music that has bass “always” and at full volume amp has average output of less than ¼ of its full power. D-class amplifier then will draw on average ¼ of its full in current. And AB-class amp a bit more. So current draw (full volume average) of that setup will probably be around 70A. If prius can only charge battery at 30A its discharging at full volume and not charging at -4db (2…4 clicks of volume less than full). Halving the power of setup will probably make it ok.
     
  7. DAM0

    DAM0 Junior Member

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    The monoblock amp I have is an ex-SPL competition amp, it will pull 350A+ continuously at 18V to make 5000w+ constant power. Class D amps have an efficiency rating of around 80%, so for 2000w of constant power at 12V it will pull 208.3A.

    Say my total current load is 320A and I have 67Ah (55Ah+12Ah) of batteries, fully charged they should be able to support the system at 100% current pull for about 12.6 minutes, independent of any charging. That's how this whole Amp-hour thing works right?

    And from time to time, I do listen to songs with constant bass throughout, so this situation will be occurring if I go ahead with it.
     
  8. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    I like this whole demo but the 12 v DC part starts at 15 minutes.
     
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  9. DAM0

    DAM0 Junior Member

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    Very interesting video, I have seen the video by that guy about MG1, MG2 and the rest of the transaxle, but not this one.

    A quick search after the video seems to say no one really knows the limits of the DC-DC converter which charges the 12VDC system, as it's exact specs were not released by toyota. - wattage of DC-DC converter ? | PriusChat

    I feel like the 3kw load that I would be adding would have quite a small effect on the overall electrical system, considering that MG1/2 can produce up to ~50kw.