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  1. #1
    dba
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    cone flap,help required

    system;

    Planar 3 RB300 Goldring 1006 with Michell Techno weight
    Sugden A21a
    Sugden CD21
    Musical Fidelity XLPS V3 phono stage
    Von Scweikert VR1on custom made stands
    decent Ash designs rack (glas shelves)

    I have taken the grills off the VR1s,and I noticed something for the first time;

    when the needle lands on the record the main drivers flap noticeably,or shake quite fst to put it another way.they then do this while the record is playing.As a test,i turned the platter off and rested the needle on the record,and tapped the deck and also got cone flap.I discovered this phenomenon whislt surfing the web.

    So what do I do? It cant be right,the drivers shouldn't wobble like that,at least i think they shouldn't!!

  2. #2
    Forum Regular royphil345's Avatar
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    http://forums.audioreview.com/showth...0769#post70769

    Basically, The cartridge works by converting movement of the stylus into movement of the speaker drivers. Larger movements of the stylus...

  3. #3
    Can a crooner get a gig? dean_martin's Avatar
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    Seems like I remember experiencing something similar when I was trying to get rid of a static electricity build up problem. I disconnected the ground (which seems counter-intuitive but I got the idea from my turntable manual of all places) and went from a felt mat to a None-felt (which you must be very careful with) with no problems since. If your floor is carpeted or you have a rug in front of your system like I did at the time, then this is the time of year when static can become a problem.

  4. #4
    Forum Regular risabet's Avatar
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    Acoustic Feedback?

    Quote Originally Posted by dba
    system;

    Planar 3 RB300 Goldring 1006 with Michell Techno weight
    Sugden A21a
    Sugden CD21
    Musical Fidelity XLPS V3 phono stage
    Von Scweikert VR1on custom made stands
    decent Ash designs rack (glas shelves)

    I have taken the grills off the VR1s,and I noticed something for the first time;

    when the needle lands on the record the main drivers flap noticeably,or shake quite fst to put it another way.they then do this while the record is playing.As a test,i turned the platter off and rested the needle on the record,and tapped the deck and also got cone flap.I discovered this phenomenon whislt surfing the web.

    So what do I do? It cant be right,the drivers shouldn't wobble like that,at least i think they shouldn't!!
    Some movement of the cone is normal with LP playback but the tapping leads me to believe that you have a breakthrough problem. Try moving the TT to a small, light table and try your test again. Same result? Yes, try a heavy massive table. Same result? Buy a new, suspended TT, just kidding. Where you place the TT is important. Try to place the unit in a bass null which you can find by walking around while playing a test CD. Listen for the area with the least bass and, if possible, stick you TT there.

    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

  5. #5
    Music Junkie E-Stat's Avatar
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    Quote Originally Posted by dba
    when the needle lands on the record the main drivers flap noticeably,or shake quite fst to put it another way.
    First thing, turn down the gain!

    Quote Originally Posted by dba
    they then do this while the record is playing.As a test,i turned the platter off and rested the needle on the record,and tapped the deck and also got cone flap.
    You're watching the cone reproducing subsonic noise. As suggested earlier, you have an isolation problem or a resonance issue arising from a bad cartridge to arm mass match.

    While glass racks are pretty, they are poor sound isolators. Is the deck sitting on a glass shelf? You may want to research the cartridge arm compatibility issue as well.

    rw

  6. #6
    dba
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    how do i turn down the gain? impossible with my amp i think

    and the cart is measured as being perfect for the RB300,the previous ccart wasnt,but i still have flap with the new Goldring 1006

  7. #7
    Music Junkie E-Stat's Avatar
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    Quote Originally Posted by dba
    how do i turn down the gain? impossible with my amp i think
    Always cue records with the volume control turned all the way down.

    Quote Originally Posted by dba
    and the cart is measured as being perfect for the RB300,the previous ccart wasnt,but i still have flap with the new Goldring 1006
    That narrows down the issue to isolation.

    rw

  8. #8
    Forum Regular royphil345's Avatar
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    It's not necessarily a cartridge / arm mismatch or an isolation problem. A bad cartridge / arm match will make things worse. Better isolation would help if the problem gets much worse at higher volumes (meaning your picking subsonic up feedback from the speakers to the turntable). It's a normal occurance with vinyl. Higher compliance MM cartridges seem to suffer the worst. (unless they have the "Dynamic Stabilizer" brush of the Shures). Most records aren't perfectly flat. When the stylus hits hills and valleys, the cartridge suspension flexes. The magnet in the cartridge is moved a greater distance across the coil than it would be from the music in the grooves of the record. A pretty powerful signal is produced, but below frequencies you can hear.

    Damping factor of the amp may be a factor, as I have noticed that this problem is worse on some systems than others with the same turntable. If your drivers aren't coming close to bottoming out, it shouldn't hurt anything.

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