Page 2 of 3 FirstFirst 123 LastLast
Results 16 to 30 of 45

Thread: sound quality varies with carpet or hardwood?

  1. #16
    Senior Member
    Join Date
    Jan 2005
    Location
    Detroit
    Posts
    381
    Quote Originally Posted by Ed Kreamer View Post
    Have you gotten a copy of Dr. Tooles book yet?
    There is a reason folks like Greg Timbers get degrees in both electronics AND acoustics.

  2. #17
    Senior Member
    Join Date
    Apr 2012
    Location
    Canada
    Posts
    436
    Quote Originally Posted by Mannermusic View Post
    There is a reason folks like Greg Timbers get degrees in both electronics AND acoustics.
    Which is why the prudent thing to do is defer to the experts. That way our experience corroborates their wisdom. However some folks prefer their ears to be tickled.

  3. #18
    Senior Member
    Join Date
    Apr 2003
    Location
    Richmond Hill, Ont.
    Posts
    4,762
    Quote Originally Posted by gasfan View Post
    Which is why the prudent thing to do is defer to the experts. That way our experience corroborates their wisdom. However some folks prefer their ears to be tickled.
    Here's what Greg Timbers had to say ( a while back ) in relation to the discussion about the 4367 ( & it's 15" woofer ) and anchoring.

    Quote Originally Posted by GT
    I used some concrete blocks to elevate the 4367's when I did Demo's at the factory. 6" to 8" height really helps. The systems are too short for typical American use. The trick is to get something that doesn't rock or tip. You will eat the bass kick immediately if any enclosure movement is allowed. The woofer kicks really hard and if any energy is consumed moving (rocking) the enclosure due to it not being properly coupled to the floor, you will lose bass kick and impact. The proper use and need for spikes (or equivalent) is not BS. It is based in sound theory and is easily demonstrable.
    "Anchoring" is a pretty broad term and ( IMO ) doesn't necessarily imply or demand the use of spikes.


  4. #19
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Rocinante
    Posts
    8,155
    "Anchoring" is a pretty broad term and ( IMO ) doesn't necessarily imply or demand the use of spikes.
    Yeah true spikes are easy though and they make great levelers!

    Rob
    "I could be arguing in my spare time"

  5. #20
    Senior Member Ian Mackenzie's Avatar
    Join Date
    Apr 2003
    Location
    Australia
    Posts
    7,326
    Hi Earl

    I think that quote would be appreciated in the 4367 first listen thread.

  6. #21
    Senior Member
    Join Date
    Sep 2008
    Location
    Germany / Hamburg
    Posts
    629
    Thanks a lot for the post from Greg Timbers!

    This is what I tried to say in post 7... The coupling to the (hard) floor enables the speaker to gain restoring forces, which yield to a hard bass kick, dynamic impact and good transient response.
    As Greg Timbers said, if there is any rocking e.g. movement of the enclosure, this energy is gone and wasted. Thatīs why I avoid decoupling speakers on hard floors.

    Of course you donīt need spikes to do this, any good coupling will do. I prefer 3 speaker stands as 4 usually tend to wobble.

  7. #22
    Senior Member
    Join Date
    Apr 2012
    Location
    Canada
    Posts
    436
    Quote Originally Posted by Earl K View Post
    Here's what Greg Timbers had to say ( a while back ) in relation to the discussion about the 4367 ( & it's 15" woofer ) and anchoring.



    "Anchoring" is a pretty broad term and ( IMO ) doesn't necessarily imply or demand the use of spikes.

    He did use the phrase "coupled to the floor", though. This is where the controversy lies. I have my Velodyne subs on 2" clay ceramic patio stones with the mentioned fiber pads on top with a rubber mat against the cab. The clay ceramic blocks any LF so there's a good test to determine whether coupling direct or isolating is best. In this scenario, you can isolate and directly couple ala Greg's assertion to "no movement" but still detach any frequencies transferring into the substrate. My uneducated experiential opinion says it's the ultimate, all things being equal, optimization in all other parameters. Why would you want the room to ring?

  8. #23
    Senior Member
    Join Date
    Sep 2008
    Location
    Germany / Hamburg
    Posts
    629
    Quote Originally Posted by gasfan View Post
    Why would you want the room to ring?
    The room will ring as well with decoupled speakers, because all the walls, floor and ceiling are still induced by air sound pressure. The impact noise which can be avoided by decoupling the speakers is just a small proportion compared to the air sound pressure...

    Nevertheless, if the speakers are very close to the turntable decoupling may is a significant improvement. In my experience a mounting-device to attach the turntable to a wall is another solution.

  9. #24
    Senior Member
    Join Date
    Apr 2012
    Location
    Canada
    Posts
    436
    Quote Originally Posted by Dr.db View Post
    The room will ring as well with decoupled speakers, because all the walls, floor and ceiling are still induced by air sound pressure. The impact noise which can be avoided by decoupling the speakers is just a small proportion compared to the air sound pressure...

    Nevertheless, if the speakers are very close to the turntable decoupling may is a significant improvement. In my experience a mounting-device to attach the turntable to a wall is another solution.
    I guess I'm calling into question your assertion that coupling the speakers directly to the substrate adds only a small % of over all resonance. My experience shows otherwise by a large extent. Could be that by the time jet plane spl is reached, coupling becomes moot but ime, the point of cancellation is no where in sight at spls of 105-110 db. The difference is quite observably large.

  10. #25
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Rocinante
    Posts
    8,155
    I guess I'm calling into question your assertion that coupling the speakers directly to the substrate adds only a small % of over all resonance.
    I have a concrete basement with a wooden first floor over it. I have my subs spiked to the basement floor. The amount of energy coupled to the wooden floor through the air can be significant. I also have an upstairs system with the sub spiked directly to the same wooden floor. There in much more energy coupled from below through the air than from the upstairs sub that is spiked directly to the floor. That's my experience.

    Rob
    "I could be arguing in my spare time"

  11. #26
    Senior Member
    Join Date
    Apr 2012
    Location
    Canada
    Posts
    436
    Quote Originally Posted by Robh3606 View Post
    I have a concrete basement with a wooden first floor over it. I have my subs spiked to the basement floor. The amount of energy coupled to the wooden floor through the air can be significant. I also have an upstairs system with the sub spiked directly to the same wooden floor. There in much more energy coupled from below through the air than from the upstairs sub that is spiked directly to the floor. That's my experience.

    Rob
    Sure, you have a concrete speaker cab with a relatively flimsy wooden sound board acting as a diaphragm. How is that a comparison to coupling/decoupling within the same listening space? Apples and oranges

  12. #27
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Rocinante
    Posts
    8,155
    Sure, you have a concrete speaker cab with a relatively flimsy wooden sound board acting as a diaphragm. How is that a comparison to coupling/decoupling within the same listening space? Apples and oranges
    Lol really a flimsy sounding board you familiar with my local building codes. Do have a clue to what that floor weighs?? So when I have a sub spiked to my flimsy sounding board I get let less coupling than from the room below. That not apples and oranges it obvious that the acoustic output from the subs bellow has a much greater effect through the air borne acoustic coupling than actually having a sub mechanically coupled to the floor with spikes.

    Rob
    "I could be arguing in my spare time"

  13. #28
    Senior Member
    Join Date
    Apr 2012
    Location
    Canada
    Posts
    436
    Quote Originally Posted by Robh3606 View Post
    Lol really a flimsy sounding board you familiar with my local building codes. Do have a clue to what that floor weighs?? So when I have a sub spiked to my flimsy sounding board I get let less coupling than from the room below. That not apples and oranges it obvious that the acoustic output from the subs bellow has a much greater effect through the air borne acoustic coupling than actually having a sub mechanically coupled to the floor with spikes.

    Rob
    Compared to concrete it might as well be cardboard. However it doesn't matter, yours is still an apples to oranges comparison. Strange your not grasping it.

  14. #29
    Senior Member Ian Mackenzie's Avatar
    Join Date
    Apr 2003
    Location
    Australia
    Posts
    7,326
    I hate to interfere with such robust discussions but JBL never mounts any floor standing directly on the floor..

    They offer two spikes and rounded metal feet with coasters to protect tiled and Lino floors.

    There is the now obvious benefit of stability to spikes but the point is the enclosure foot print is large compared to the contact area.

    Common sense suggests a large surface area is more likely to allow transmission of vibrations or audible sound in either direction from floor to the loudspeaker and loudspeaker to the floor if the enclosure is directly on the floor the large surface area has less pressure per square inch than the spikes and is likely to move or resonate on the floor at variety of frequencies. (either boards or carpet). The audibility of this needs to be assessed but I think most people recognise an audible difference when compared either way.

  15. #30
    Senior Member
    Join Date
    Apr 2012
    Location
    Canada
    Posts
    436
    Quote Originally Posted by Ian Mackenzie View Post
    I hate to interfere with such robust discussions but JBL never mounts any floor standing directly on the floor..

    They offer two spikes and rounded metal feet with coasters to protect tiled and Lino floors.

    There is the now obvious benefit of stability to spikes but the point is the enclosure foot print is large compared to the contact area.

    Common sense suggests a large surface area is more likely to allow transmission of vibrations or audible sound in either direction from floor to the loudspeaker and loudspeaker to the floor if the enclosure is directly on the floor the large surface area has less pressure per square inch than the spikes and is likely to move or resonate on the floor at variety of frequencies. (either boards or carpet). The audibility of this needs to be assessed but I think most people recognise an audible difference when compared either way.
    Post#22

    The point of contention is what percentage of over all resonance is influenced by this parameter. IMO it's large.

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. Jbl 4350a 2231a vs 2235 recone sound quality
    By JoeNelis in forum Lansing Product DIY Forum
    Replies: 15
    Last Post: 05-14-2018, 11:58 PM
  2. JBL D131 sound quality
    By bran kulez in forum Lansing Product DIY Forum
    Replies: 4
    Last Post: 12-25-2011, 05:38 PM
  3. MD vs MP3 sound quality
    By SEAWOLF97 in forum General Audio Discussion
    Replies: 15
    Last Post: 04-29-2009, 03:37 PM
  4. I'm surprised at the sound quality
    By Boss96 in forum Lansing Product General Information
    Replies: 4
    Last Post: 11-16-2004, 07:12 AM

Posting Permissions

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