Page 2 of 2 FirstFirst 1 2
Results 26 to 38 of 38
  1. #26
    Forum Regular audio amateur's Avatar
    Join Date
    Mar 2006
    Location
    France
    Posts
    2,524

    Come here and you'll believe it.

    Quote Originally Posted by Feanor
    You may feed your system 40 Hz and you might get -3 dB. But here's the catch: you might not be hearing a pure 40 Hz sound. Instead you are getting distortion.

    In a rooms too small to reproduce a certain frequency, all that power you're feeding has to go somewhere. It creates distorted sound at a higher frequency than the input signal.
    I think it's safe to say I can hear the difference between a disorted 40Hz sound and one that is not. A 40Hz sine wave doesn't sound anymore distorted than one of 80Hz, at a reference amplitude. The cone's excursion is well within its limits when I do this. My room seems to produce a peak between approx. 40 and 45Hz which helps to extend the 686's bass. I was quite dumbfounded at first with their bass extention.

    'YMMV', as they say around here. But I don't think you're in a position to argue
    or perhaps I'm utterly wrong and i've forgotten something in the equation..

  2. #27
    Suspended atomicAdam's Avatar
    Join Date
    Apr 2008
    Location
    Oaktown!
    Posts
    1,774
    Quote Originally Posted by audio amateur
    I think it's safe to say I can hear the difference between a disorted 40Hz sound and one that is not. A 40Hz sine wave doesn't sound anymore distorted than one of 80Hz, at a reference amplitude. The cone's excursion is well within its limits when I do this. My room seems to produce a peak between approx. 40 and 45Hz which helps to extend the 686's bass. I was quite dumbfounded at first with their bass extention.

    'YMMV', as they say around here. But I don't think you're in a position to argue
    or perhaps I'm utterly wrong and i've forgotten something in the equation..
    what about diagonal distance? from the bottom left corner to upper right corner.

    maybe there is enough distance there to let the wave travel. rooms arent 2D

  3. #28
    Phila combat zone JoeE SP9's Avatar
    Join Date
    Jun 2003
    Location
    Philadelphia, PA
    Posts
    2,710
    I did a quick calculation using the longest diagonal in the room the Fq that resulted was 75Hz. This is using 8Ft. as the ceiling height.
    ARC SP9 MKIII, VPI HW19, Rega RB300
    Marcof PPA1, Shure, Sumiko, Ortofon carts, Yamaha DVD-S1800
    Behringer UCA222, Emotiva XDA-2, HiFimeDIY
    Accuphase T101, Teac V-7010, Nak ZX-7. LX-5, Behringer DSP1124P
    Front: Magnepan 1.7, DBX 223SX, 2 modified Dynaco MK3's, 2, 12" DIY TL subs (Pass El-Pipe-O) 2 bridged Crown XLS-402
    Rear/HT: Emotiva UMC200, Acoustat Model 1/SPW-1, Behringer CX2310, 2 Adcom GFA-545

  4. #29
    It's all about the music. Doc Sage's Avatar
    Join Date
    Oct 2008
    Location
    Victoria, BC, Canada
    Posts
    55
    To take this one step further...

    Does this explain why, when you hear loud music coming from a car, the bass thump always seems to be at the same frequency?

    Doc Sage

  5. #30
    Retro Modernist 02audionoob's Avatar
    Join Date
    Jun 2008
    Location
    Dallas, TX
    Posts
    2,908
    Quote Originally Posted by atomicAdam
    what about diagonal distance? from the bottom left corner to upper right corner.

    maybe there is enough distance there to let the wave travel. rooms arent 2D
    And in one more direction...what about the diagonal from front bottom left to rear top right?

  6. #31
    Phila combat zone JoeE SP9's Avatar
    Join Date
    Jun 2003
    Location
    Philadelphia, PA
    Posts
    2,710
    Quote Originally Posted by 02audionoob
    And in one more direction...what about the diagonal from front bottom left to rear top right?
    See my post No. 28 in this thread.
    ARC SP9 MKIII, VPI HW19, Rega RB300
    Marcof PPA1, Shure, Sumiko, Ortofon carts, Yamaha DVD-S1800
    Behringer UCA222, Emotiva XDA-2, HiFimeDIY
    Accuphase T101, Teac V-7010, Nak ZX-7. LX-5, Behringer DSP1124P
    Front: Magnepan 1.7, DBX 223SX, 2 modified Dynaco MK3's, 2, 12" DIY TL subs (Pass El-Pipe-O) 2 bridged Crown XLS-402
    Rear/HT: Emotiva UMC200, Acoustat Model 1/SPW-1, Behringer CX2310, 2 Adcom GFA-545

  7. #32
    Music Junkie E-Stat's Avatar
    Join Date
    Dec 2003
    Posts
    5,462
    Quote Originally Posted by audio amateur
    I think it's safe to say I can hear the difference between a disorted 40Hz sound and one that is not. A 40Hz sine wave doesn't sound anymore distorted than one of 80Hz, at a reference amplitude. The cone's excursion is well within its limits when I do this. My room seems to produce a peak between approx. 40 and 45Hz which helps to extend the 686's bass. I was quite dumbfounded at first with their bass extention.
    I'm largely agreeing with your assessment, but do have a couple of caveats based upon Feanor's comments:

    1. As you indicated, the primary frequency of your room is around 45hz so you are getting some room gain. If the other walls are even multiples, this factor will be enhanced. My room back in Atlanta was 30x15x7.5. The fundamental frequency was just below 20 hz, reinforced by the room multiples and created a most entertaining bass effect near the back wall. The bass drum on Dead Can Dance's "Yulunga" cut shook the room. Not real, but fun! My current room is more neutral and lacks that euphonic reinforcement.

    2. The primary distortion component of dynamic woofers is doubling. Which as the name suggests is second order harmonic distortion delivered at relatively high levels for small drivers at the bottom octave (up to10% or so) as compared with amplifiers. Aside: Feanor often opines that tube fanciers favor them because of this same factor. First of all, the magnitude of distortion with phono/line stages remains in the fractional percent category. Even my '81 ARC SP-6 had only 0.01%. With tube amps, not only is the peak result much lower (3%), the figure remains below 1% up to -3db output for modern pentode designs. So, back to speakers - what does that mean? Woofer distortion sounds good. Some may say better. It is consonant to the fundamental and adds "richness". Some of what you are hearing could be doubling even when the driver is within its excursion limits.

    rw

  8. #33
    Class of the clown GMichael's Avatar
    Join Date
    Apr 2005
    Location
    Anywhere but here...
    Posts
    13,243
    I seem to get very good bass from my car system. Sounds great. Very low. Very little distortion.
    WARNING! - The Surgeon General has determined that, time spent listening to music is not deducted from one's lifespan.

  9. #34
    ***** Irregular yogo's Avatar
    Join Date
    Feb 2002
    Location
    Blanchester, Ohio
    Posts
    58
    Quote Originally Posted by atomicAdam

    The speakers are pointed length wise
    I've read somewhere on this site that in a long room you should not run your speakers lengthwise. More like this:

    xxxxxxxxxxxxxxxxxxxxx
    x---------O----------O----------x
    x----------------------------------x
    x----------------------------------x
    x----------------------------------x
    xxxxxxxxxxxxxxxxxxxxx

    than this:

    xxxxxxxxxxxxxxxxxxxxx
    x---------------------------------x
    x O------------------------------x
    x--------------------------------- x
    x O-------------------------------x
    x----------------------------------x
    xxxxxxxxxxxxxxxxxxxxx

    Worth a shot if nothing else works. That might tame any undesirable effects between your speakers and sub. Luck...

  10. #35
    Sure, sure... Auricauricle's Avatar
    Join Date
    Jun 2008
    Location
    Yonder
    Posts
    2,886
    So it sounds like, unless you have accomodations of space to support frequencies produced by the subwoofer, your screwed!

    Boy, I can imagine quite a few thousand audiophiles are getting pretty hoppy, now!
    "The great tragedy of science--the slaying of a beautiful hypothesis by an ugly fact."--T. Huxley

  11. #36
    Suspended atomicAdam's Avatar
    Join Date
    Apr 2008
    Location
    Oaktown!
    Posts
    1,774
    Quote Originally Posted by Auricauricle
    So it sounds like, unless you have accomodations of space to support frequencies produced by the subwoofer, your screwed!

    Boy, I can imagine quite a few thousand
    audiophiles are getting pretty hoppy, now!
    Hoppy? Sure does make you wonder.

    Well, at least for me it should only be a month or two more in the small room. If Bush did anything I could thank him for the economy and housing prices are so screwed up I can affors a house.

  12. #37
    Sure, sure... Auricauricle's Avatar
    Join Date
    Jun 2008
    Location
    Yonder
    Posts
    2,886
    Yeah, "hoppy". As in quite upset, miffed, po'd, peeved, irked, irritated, annoyed, riled, fed-up, ruffled...


  13. #38
    Suspended atomicAdam's Avatar
    Join Date
    Apr 2008
    Location
    Oaktown!
    Posts
    1,774
    Quote Originally Posted by Auricauricle
    Yeah, "hoppy". As in quite upset, miffed, po'd, peeved, irked, irritated, annoyed, riled, fed-up, ruffled...

    IC - that is what I thought.

    For me Hoppy =

Page 2 of 2 FirstFirst 1 2

Thread Information

Users Browsing this Thread

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

Posting Permissions

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