Trying To Prove A Point

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  • 11-17-2009, 09:45 PM
    BallinWithNash
    Trying To Prove A Point
    Hey, guys what takes more power to reproduce .... a high note or a low note?
    So in other words the lower the note the more power or the higher the note the more power?
  • 11-17-2009, 09:50 PM
    dakatabg
    I don't know exactly what you mean? Are you talking about the piano or saxophone notes or what?
  • 11-17-2009, 09:53 PM
    BallinWithNash
    i mean in general for an amplifier does it take more power as in watts to produce a high note or a low note
  • 11-17-2009, 09:57 PM
    dakatabg
    It takes more to reproduce low
  • 11-17-2009, 10:05 PM
    BallinWithNash
    Now guys can you please help me out haha
    http://www.youtube.com/comment_servl...eature%3Demail

    Just cntrl F and type in BallinWithNash and read the short conversation
    Thank you in advance!
  • 11-18-2009, 02:14 AM
    harley .guy07
    Well in general it takes more power to reproduce lower notes since the signal wave is slower and the speaker motor structure and driver is larger in lower frequency producing units and it takes more power to move bigger drivers at slower speeds. Its pretty simple logic really. It takes a bigger more powerful motor to make a bigger car run faster or the same speed as a smaller car with a smaller motor. That is why powered subwoofers have anywhere from a couple hundred watts to over 1000 and most home audio 2 channel amps do not go much over 350 per channel and thats a big amp, generally 100 to 150 is generally where most people have their systems and thats usually all thats needed unless you are running some really big power pig speakers or play your music very loud.
  • 11-18-2009, 05:58 AM
    E-Stat
    Quote:

    Originally Posted by BallinWithNash
    Now guys can you please help me out haha

    You are correct, but understand that the uh, *program material* played on car stereos rarely contains first octave bass at the same level as the mid bass. So, for an average recording, the mid bass might require more excursion overall than a more demanding, but lower level signal.

    I was amused by the guy's "woofer moves faster at higher frequencies" explanation. :)

    rw
  • 11-18-2009, 07:19 AM
    Ajani
    Quote:

    Originally Posted by E-Stat
    I was amused by the guy's "woofer moves faster at higher frequencies" explanation. :)

    Are we sure BallinWithNash isn't arguing with Pixelthis on that site? That woofer moves faster explanation sounds very similar to an argument Pix had about why tweeters need more power than woofers....

    I think the reason people come to the conclusion Pix and the guy on youtube do, is because they confuse Continuous Power with Peak Power... Tweeters and Mid Range Drivers will tend to require low but continuous power as they are constantly moving. Bass Drivers will be moving less frequently but require large bursts of power when they do move. So at the end of a 5 minute song, the TOTAL power used by the Tweeters/Mid might have exceeded the Bass driver.
  • 11-18-2009, 07:56 AM
    GMichael
    Quote:

    Originally Posted by Ajani
    Are we sure BallinWithNash isn't arguing with Pixelthis on that site? That woofer moves faster explanation sounds very similar to an argument Pix had about why tweeters need more power than woofers....

    I think the reason people come to the conclusion Pix and the guy on youtube do, is because they confuse Continuous Power with Peak Power... Tweeters and Mid Range Drivers will tend to require low but continuous power as they are constantly moving. Bass Drivers will be moving less frequently but require large bursts of power when they do move. So at the end of a 5 minute song, the TOTAL power used by the Tweeters/Mid might have exceeded the Bass driver.

    That's what I was thinking too. Tweeters don't demand a sudden burst of power to drive a 12 inch speaker and shake the house. This demand is why people who want to play deep bass loudly need big amps.
  • 11-18-2009, 10:46 AM
    harley .guy07
    that was pretty much the point I was trying to make but e-stat,Ajani,Gmichael just had a better way of explaining it. Mid and Tweets are like driving 60 miles an hour down a 50 miles highway and need clean constant power to do so. While a 12" woofer only needs short burts of power like a car does at the dragstrip. Over the long haul the program material will tell which uses more power in the long run but I will say that bass is what eats up dynamic headroom on amps most of the time.
  • 11-18-2009, 03:29 PM
    BallinWithNash
    Quote:

    Originally Posted by Ajani
    Tweeters and Mid Range Drivers will tend to require low but continuous power as they are constantly moving. Bass Drivers will be moving less frequently but require large bursts of power when they do move. So at the end of a 5 minute song, the TOTAL power used by the Tweeters/Mid might have exceeded the Bass driver.

    But in most songs there is always bass being played kick drum, bass guitar so wouldn't the bass driver still need continuous power?
  • 11-18-2009, 03:30 PM
    BallinWithNash
    and thanks guys for the support ... this guy just doesn't seem to get it though haha
  • 11-18-2009, 03:36 PM
    harley .guy07
    Quote:

    Originally Posted by BallinWithNash
    But in most songs there is always bass being played kick drum, bass guitar so wouldn't the bass driver still need continuous power?

    I think that what they are trying to say is that midrange and lower treble frequencies are where most of your music is and so clean power is a very important part of producing these frequencies accurately and while there is information in the bass area it does not match the amount of overall music information in the midrange and lower treble frequencies which is arguably the most important area of concern in reproducing music accurately.
  • 11-18-2009, 03:40 PM
    BallinWithNash
    Thanks, that makes sense now haha i really didn't get it before
  • 11-18-2009, 03:46 PM
    harley .guy07
    another thing to think about is the people you are refering to. They are car audio people that are probably more concerned about wining a spl contest than overall sound quality of their systems and I have seen a lot of this in my are. They have 4000 watts running 6 subs and have 200 watts running half ass descent mids and highs in their cars and the musical quality of their systems sucks and the only thing they are worried about is trying to be louder than the next guy and E-Stat is right by saying that most of these systems are way heavy on the mid bass for spl reasons and are way overdone and boomy sounding. In fact they even have cds out that take advantage of this boomy midbass to gain higher spl in sound off contests. if you would put a real bands music in there systems they would probably sound like total ass
  • 11-18-2009, 03:51 PM
    BallinWithNash
    yea i agree completely with that but it doesn't change the fact that it takes more power to produce a lower frequency right? or does it I mean you can EQ the boomy part way up so I guess in that scenario it would be drawing more power then the lower frequencies but if you dont EQ it shouldn't the low frequency require more power?
  • 11-18-2009, 05:08 PM
    Mr Peabody
    I will have to do some research but I'm thinking the woofer would take more power long term even though the tweeter does move faster. In putting together car and sound reinforcement we've always used larger amps on the bottom end over mids/highs. It definitely takes more power to recreate a bass note.

    I'd say 99% of those using big auto audio systems have no idea what good bass response should or does sound like. They are so over driven a bass line or single note is non-existent. It's not the size of the amp but abuse of the gain control. Distortion off the chart.
  • 11-18-2009, 05:27 PM
    hermanv
    The woofer cone is much smaller than the wavelength being produced (100 Hz is 11 feet ) so the coupling efficiency to the air is very poor. Bass drivers overcome this problem by having larger excursions. You can't see a tweeter move (max excursion of 1mm or 2mm) but a woofer can easily be seen to move for loud low frequency notes (max excursion of 10mm or 20mm typical). So the woofer moves a larger cross section a greater distance or simply put, a lot more air, this takes more power.
  • 11-18-2009, 05:47 PM
    RoyY51
    When Pix was insisting that it took more power to drive a tweeter than a woofer, I listed several models of powered speakers along with their specs, Without exception, every speaker featured a higher-wattage amp for the woofer and a lower-wattage one for the tweeter. Since Pix never responded, I'm assuming that he came to the conclusion that he (just possibly) might be incorrect.

    If you google "bi-amped powered speakers" you'll see what I mean.
  • 11-21-2009, 02:20 AM
    BallinWithNash
    ok guys how do I prove this ... like legitimately prove this .. is there some math formula's I can use or what?
  • 11-21-2009, 05:45 AM
    Geoffcin
    If you have a theoretical "perfect" speaker that has a FLAT response from 20hz-20khz. and it's sensitivity (efficiency) is 90dB @ 1 watt. (2.83v) then a 1 watt input of a sine wave at 20hz would make a 90dB sound, and a 1 watt input at 20khz would ALSO make a 90 dB sound.
  • 11-21-2009, 06:25 AM
    E-Stat
    Quote:

    Originally Posted by Geoffcin
    If you have a theoretical "perfect" speaker that has a FLAT response from 20hz-20khz. and it's sensitivity (efficiency) is 90dB @ 1 watt. (2.83v) then a 1 watt input of a sine wave at 20hz would make a 90dB sound, and a 1 watt input at 20khz would ALSO make a 90 dB sound.

    Yet, in the real world such is never the case. Has anyone ever seen a multi-way active speaker where the power of the individual amps increased from low to high?

    ATC Monitor

    rw
  • 11-21-2009, 06:55 AM
    audio amateur
    Quote:

    Originally Posted by E-Stat
    Yet, in the real world such is never the case. Has anyone ever seen a multi-way active speaker where the power of the individual amps increased from low to high?

    ATC Monitor

    rw

    Yup, many actively bi/tri/quad amped speakers use more power as you go from the tweet to the bass driver. Cabasse's 'La Sphere' is an example of this.
  • 11-21-2009, 06:58 AM
    Mr Peabody
    Here's a reference to home subs and the article states your point: http://hometheater.about.com/cs/loud...subwoofera.htm

    This is about reproducing bass from an instrument and states your point: http://en.wikipedia.org/wiki/Bass_in..._amplification

    Also if anyone heard a lead guitar through 10 watts vs. a bass at 50 watts would not have a problem believing.

    This guy seems to have it right: http://everything2.com/title/Subwoofer

    States your point, eventually: http://jazztimes.com/articles/21033-power-to-the-people

    This gets to the point and is related to car audio: http://hubpages.com/hub/car-speakers

    I didn't find a physics lesson but if they can't accept this simple concept I doubt if the physics behind it would do anything. How some one can be into car audio and not understand such a basic principle is beyond me. Do they run 500 watts to the mid/high and 100 to the woofer? They are either yanking your chain or dumber than rocks.
  • 11-21-2009, 07:02 AM
    Mr Peabody
    You know, maybe you are going about this the wrong way. Present your info and then ask them to find something to prove highs require more power than bass. Once they find that task futile, perhaps they might be convinced.