Results 1 to 9 of 9
  1. #1
    Forum Regular
    Join Date
    Sep 2004
    Posts
    727

    Bass frequency response question

    My title may be misleading but I didn't know how else to word it.

    We know that the lowest note (open E) on a bass violin is roughly 41 hz, same as on a bass guitar. I've listened to music on several speakers that roll off at 60 hz or even higher. It's obvious that the bass weight is minimal, yet a 41 hz tone can be heard. The presentation is lightweight but the bass notes are easily discernible, if not terribly powerful.

    I've read that low bass notes disappear when the speakers can't handle them. So how is it that the bass can be heard on these speakers (or cheap car speakers or 3 inch radio speakers, etc) when they are not designed to do so? Bass is bass, is it not? Frequency is frequency, correct? Doesn't air have to move to create bass? So how are these bass notes even audible? I cannot hear below 25 hz on my main speakers and have listened to music that contains some known bass notes below that. They are totally inaudible.

    Does my question make any sense? Thanks for any thoughts!

  2. #2
    Forum Regular N. Abstentia's Avatar
    Join Date
    Apr 2004
    Posts
    2,671
    If a speaker starts to roll off at 60 hz then each octave will just be less loud. For example if it rolls off at 6db/octave at 60hz, then 30hz will just simply be 6db quieter, then 15hz 12db quieter..etc...it doesn't just magiacally stop, it rolls off.

  3. #3
    Suspended markw's Avatar
    Join Date
    Dec 2001
    Location
    Noo Joisey. Youse got a problem wit dat?
    Posts
    4,659
    When you "pluck" the string, along with the fundamantal frequency/tone, it also produces higher order harmonics of the root frequency. Using your 41 hz example these would be 82, 123, 164, etc..., with each harmonic diminishing in level. These are what defines the actual character, or sound, of what you hear. That 41 hz note sounds different on each insturmentr, be it an organ, a bass guitar and a synthesizer. Otherwise, it would all sound like an electronicaly generated tone. ...deep, but with no personality.

    Many speakers that cannot produce fundamantal tones live their lives quite happily by doing a good job on the harmonics, thereby giving the "illusion" of producing deep bass.

    Our ears, amazing things that they are, can recognize these harmonics as the anticipated byproducts of a fundamental note and will obligingly "fill in" the missing fundamantal that we expect to hear.

    This, and other little traits of our "hearing" is well known and prety well documented. That's why the old "I know what I hear" is looked upon with a certain amount of skepticism by some here.
    Last edited by markw; 12-30-2004 at 02:19 PM.

  4. #4
    BooBs are elitist jerks shokhead's Avatar
    Join Date
    Dec 2004
    Location
    So Cal
    Posts
    1,994
    Hard to hear something that a speaker just cant reproduce. Listen to a good DVD on a something thats good down to 35-40 and then the same movie on something thats good down to 25 or so and then you'll hear what you've been missing. Hard to know what your missing when you've never heard it. Is that right or am i all screwed up? LOL

  5. #5
    Forum Regular
    Join Date
    Sep 2004
    Posts
    727
    Thanks - that makes a lot of sense. N Absentia's response is accurate as well but the bass really was just as loud as the rest of the music - it just had no weight, no heft to it. Your response explains why.

  6. #6
    DIYaudiophilehack
    Join Date
    Jan 2003
    Location
    RI
    Posts
    215
    A 41hz bass note is centered at 41hz, but there is plenty of other musical information above and below that frequency that is associated with it. Your brain registers this other musical information and associates it with the 41hz fundmental so you "hear" the note, but in reality your only hearing the parts of the note that the speakers are able to reproduce accurately. This is why it may sound "thin", because you're not hearing the whole note. Also as noted, your speakers don't stop dead at 60hz, they simply don't play the 41hz portion of the note as loudly.

  7. #7
    BooBs are elitist jerks shokhead's Avatar
    Join Date
    Dec 2004
    Location
    So Cal
    Posts
    1,994
    Quote Originally Posted by toenail
    A 41hz bass note is centered at 41hz, but there is plenty of other musical information above and below that frequency that is associated with it. Your brain registers this other musical information and associates it with the 41hz fundmental so you "hear" the note, but in reality your only hearing the parts of the note that the speakers are able to reproduce accurately. This is why it may sound "thin", because you're not hearing the whole note. Also as noted, your speakers don't stop dead at 60hz, they simply don't play the 41hz portion of the note as loudly.
    And the lower the Hz,the less loud your speaker will play it. Thats how some lie. This speaker plays down to 30Hz.. Of course it has to be so low you cant hear it and when you turn it up,opps. Thats why i dont think an 8" sub will do the job for a HT. It might get down to 28 or 30 but not loud enough to be worth it.
    Look & Listen

  8. #8
    Music Junkie E-Stat's Avatar
    Join Date
    Dec 2003
    Posts
    5,462
    Quote Originally Posted by musicoverall
    Frequency is frequency, correct? Doesn't air have to move to create bass? So how are these bass notes even audible? I cannot hear below 25 hz on my main speakers and have listened to music that contains some known bass notes below that. They are totally inaudible.
    I agree with Markw's answer that so much of what you hear is the harmonic structure as opposed to the fundamentals. My system responds down to 30 hz, yet really does not reproduce fundamentals down there with any authority. This is readily apparent when you hear something like a pair of Nola Exoticas (formerly Alon) that can. Like HP's system. It can move copious amounts of air totally effortlessly with its huge bass towers .

    rw

  9. #9
    Forum Regular risabet's Avatar
    Join Date
    Dec 2004
    Location
    SoCal
    Posts
    177
    Go find an organ recital at a church or hall in your area and just sit and listen to the pedal notes. Not only will you hear true low bass but you will feel the lower notes in your viscera. I have heard of people being made nauseous by sutained bass notes from large organs.

    Linn LP-12 (Origin Live Advanced PS w/DC Motor) Benz "ACE" medium output*TAD-150*Tube Audio Design TAD-1000 monoblocs*Parasound CD-P 1000*NAD 4020A Tuner*Velodyne F-1000 Subwoofer*Toshiba SD-4700 DVD*Motorola DTP-5100 HD converter*Pioneer PDP-4300*Martin-Logan Clarity*Audioquest cables and interconnects* Panamax 5100 power conditioner

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Using 2 subs in home theater
    By ryjam282 in forum Home Theater/Video
    Replies: 22
    Last Post: 12-26-2004, 07:57 PM
  2. Frequency Response
    By SAPSEC in forum Speakers
    Replies: 13
    Last Post: 12-17-2004, 08:21 PM
  3. RGA Reviews Page 3 - yes still more.
    By RGA in forum Speakers
    Replies: 30
    Last Post: 09-11-2004, 05:10 PM
  4. Subwoofer placement vs. room modes (standing waves)
    By Richard Greene in forum Speakers
    Replies: 2
    Last Post: 02-27-2004, 05:40 PM
  5. Dual sub-woofers??
    By kexodusc in forum Home Theater/Video
    Replies: 34
    Last Post: 02-22-2004, 12:26 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •