Polk LSI Tweeters Blown?

wingnut4772
wingnut4772 Posts: 7,519
edited March 2005 in Troubleshooting
Hi guys . I have Polk LSI15 fronts and LSIC center. They have been powered by an Outlaw Audio 7100 amp which is rated at 165 w per @ 4 ohms (all channels running).

I am hearing some distortion during diologue especially from my center channel ( since that's where the dialogue is mostly) . This occurs at all volumes . My 15s are having some distortion also . What is causing this? I am already replacing them and have purchased a new amp-- An Outlaw Audio 770 which is rated at 300 w per @ 4 ohms ( all running). Is it possible they were underpowered with the 7100? At 165 W?! has anyone else had experience with this issue? Thanks in advance.
Sharp Elite 70
Anthem D2V 3D
Parasound 5250
Parasound HCA 1000 A
Parasound HCA 1000
Oppo BDP 95
Von Schweikert VR4 Jr R/L Fronts
Von Schweikert LCR 4 Center
Totem Mask Surrounds X4
Hsu ULS-15 Quad Drive Subwoofers
Sony PS3
Squeezebox Touch

Polk Atrium 7s on the patio just to keep my foot in the door.
Post edited by wingnut4772 on
· Share on FacebookShare on Twitter

Comments

  • F1nut
    F1nut Posts: 50,561
    edited March 2005
    You're already replacing the speakers? How do you know they have a problem? It could very well be the amp or the AVR or the source, etc. You need to find the problem first before replacing everything. Since the distortion is in all your speakers I'd have to say it's not the speakers, but more likely up stream.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."

    President of Club Polk

    · Share on FacebookShare on Twitter
  • pjdami
    pjdami Posts: 1,894
    edited March 2005
    I have never heard of anyone blowing a Vifa LSi tweeter. The 7100 is an impressive and capable amp which other members of this forum run successfully. I believe Frank Z has that amp with the LSi and highly recommends it.

    I agree with F1nut. May be a source problem that is affecting all channels.

    Is the distortion something you are confusing with sibilance? Sibilance is a hissing sound (ssssss...) and depending on sources / wiring the LSi C can be very sibilant when watching movies on a DVD player. Dialogue can be difficult to understand. I upgraded my receiver, wiring, and DVD player to fix the problem. Also remember to use the little rubber feet to isolate the center speaker from whatever it is resting on.

    One final question is if you are consistently listening to music at 95 - 100 db or higher (which is pretty loud)?

    Paul
    · Share on FacebookShare on Twitter
  • wingnut4772
    wingnut4772 Posts: 7,519
    edited March 2005
    In the past 3 weeks I have :

    1.Changed my Pre/Pro from an Outlaw Audio 950 to a Sherwood Newcastle P-965

    2. Upgraded all my interconnects to Cobalt Cable

    3. Upgraded my amp from the Outlaw
    7100 to 770

    4. Placed Auralex Isolators under all speakers- including the center.

    No changes in the distortion (although my overall sound is MUCH improved- mainly due to the Sherwood) It occurs on both satellite and DVD. I traded in my old pair of LSIs for the 'New' version and they do sound better. I am waiting for the LSIC from Crutchfield. I do know the difference between sibilance and distortion although I am sure that it is confusing to a lot of people . I also adjusted my Sony DVD audio filter to Slow from Sharp and turned the attenuation 'on'.

    Since the center seems to be the primary offender, I will just have to wait until my replacement is shipped.

    I appreciate the fast replies and input. One thing I am not sure of is clipping. What is it exactly? Is it possible that this happened? I have to say I do not listen loudly at all. 20 to 15 db at the most (absolute). I live in a townhouse and I would like happy neighbors.






    :p
    Sharp Elite 70
    Anthem D2V 3D
    Parasound 5250
    Parasound HCA 1000 A
    Parasound HCA 1000
    Oppo BDP 95
    Von Schweikert VR4 Jr R/L Fronts
    Von Schweikert LCR 4 Center
    Totem Mask Surrounds X4
    Hsu ULS-15 Quad Drive Subwoofers
    Sony PS3
    Squeezebox Touch

    Polk Atrium 7s on the patio just to keep my foot in the door.
    · Share on FacebookShare on Twitter
  • wingnut4772
    wingnut4772 Posts: 7,519
    edited March 2005
    I though of an example of the distortion that most Home Theater hobbyists would know of. In 'Attack of the Clones" in the scene when Amidala falls out of the transport, Anakin yells to go back . Here his voice distorts on my system. It usually does happen when people are yelling or genuinely stressing their voices either in dialogue or singing.
    Maybe it is the source here?
    Sharp Elite 70
    Anthem D2V 3D
    Parasound 5250
    Parasound HCA 1000 A
    Parasound HCA 1000
    Oppo BDP 95
    Von Schweikert VR4 Jr R/L Fronts
    Von Schweikert LCR 4 Center
    Totem Mask Surrounds X4
    Hsu ULS-15 Quad Drive Subwoofers
    Sony PS3
    Squeezebox Touch

    Polk Atrium 7s on the patio just to keep my foot in the door.
    · Share on FacebookShare on Twitter
  • VR3
    VR3 Posts: 28,647
    edited March 2005
    You don't have enough ****$ to kick the LSi any farther...

    Your listening MUCH to loud, and your leaving ZERO room for headroom..so when ANYTHING dynamic happens...everything is maxing out...
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
    · Share on FacebookShare on Twitter
  • wingnut4772
    wingnut4772 Posts: 7,519
    edited March 2005
    My error....I meant -20 to -15 tops. Yeah 20 would be way over the top...especially since my receiver only goes to 10! :D
    Sharp Elite 70
    Anthem D2V 3D
    Parasound 5250
    Parasound HCA 1000 A
    Parasound HCA 1000
    Oppo BDP 95
    Von Schweikert VR4 Jr R/L Fronts
    Von Schweikert LCR 4 Center
    Totem Mask Surrounds X4
    Hsu ULS-15 Quad Drive Subwoofers
    Sony PS3
    Squeezebox Touch

    Polk Atrium 7s on the patio just to keep my foot in the door.
    · Share on FacebookShare on Twitter
  • Frank Z
    Frank Z Posts: 5,860
    edited March 2005
    Have you tried replacing the center speaker with another speaker to see if the noise/distortion is still there? Swap the inputs on the amp and see (listen) what happens.
    9/11 - WE WILL NEVER FORGET!! (<---<<click)
    2005-06 Club Polk Football Pool Champion!! :D
    · Share on FacebookShare on Twitter
  • wingnut4772
    wingnut4772 Posts: 7,519
    edited March 2005
    I tried that with the LSI15 right channel and it sounds fine. I wonder what happened to the center? (and the old 15s for that matter). Oh well, new one is on the way !:)
    Sharp Elite 70
    Anthem D2V 3D
    Parasound 5250
    Parasound HCA 1000 A
    Parasound HCA 1000
    Oppo BDP 95
    Von Schweikert VR4 Jr R/L Fronts
    Von Schweikert LCR 4 Center
    Totem Mask Surrounds X4
    Hsu ULS-15 Quad Drive Subwoofers
    Sony PS3
    Squeezebox Touch

    Polk Atrium 7s on the patio just to keep my foot in the door.
    · Share on FacebookShare on Twitter
  • heiney9
    heiney9 Posts: 25,165
    edited March 2005
    This is just a shot in the dark. But I've read that on some multi channel recordings there can be some distortion in the AC-3 channel, which I believe is the center channel for one of the Dolby settings. Again a shot in the dark, and I'm not a HT guy so I may be totally off base. I'm sure others will correct me if that's the case.

    Do you get distortion listening to cd's or just on DVD movies?

    Heiney9
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Pangea AC14SE MKII | Legend L600 | BlueSound Node 3 - Tubes add soul!
    · Share on FacebookShare on Twitter
  • wingnut4772
    wingnut4772 Posts: 7,519
    edited March 2005
    Both really but since I have brand new LSI15s it is only the center channel now that is acting up. I did try the center channel input on the R/LSI15 and it was fine . Some material can be bad though so I tried various things.
    Sharp Elite 70
    Anthem D2V 3D
    Parasound 5250
    Parasound HCA 1000 A
    Parasound HCA 1000
    Oppo BDP 95
    Von Schweikert VR4 Jr R/L Fronts
    Von Schweikert LCR 4 Center
    Totem Mask Surrounds X4
    Hsu ULS-15 Quad Drive Subwoofers
    Sony PS3
    Squeezebox Touch

    Polk Atrium 7s on the patio just to keep my foot in the door.
    · Share on FacebookShare on Twitter
  • heiney9
    heiney9 Posts: 25,165
    edited March 2005
    Originally posted by wingnut4772
    Both really but since I have brand new LSI15s it is only the center channel now that is acting up. I did try the center channel input on the R/LSI15 and it was fine . Some material can be bad though so I tried various things.

    I can feel for you. Problems like this are notoriously annoying and hard to isolate sometimes. I used to have a problem with intermittent distortion when I played certain concert DVD's. It was faint but it was there. I have a 2-channel set up. I finally discovered that the distortion was caused by my halogen light. At a certain dimness setting it was causing this static distortion, but only on DVD's. Took awhile to track it down, but now no problems at all.

    Another problem I had was a transformer hum from my amp. After months I figured out everytime I plugged a humidifier into an outlet on the same circuit the transformer would hum.

    My point being, keep looking for things that are unlikely, because sometimes the obvious isn't causing the problem.

    Again Good Luck

    Heiney9
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Pangea AC14SE MKII | Legend L600 | BlueSound Node 3 - Tubes add soul!
    · Share on FacebookShare on Twitter
  • F1nut
    F1nut Posts: 50,561
    edited March 2005
    Heiney, you really need a dedicated line.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."

    President of Club Polk

    · Share on FacebookShare on Twitter
  • wingnut4772
    wingnut4772 Posts: 7,519
    edited March 2005
    I actually did trouble shoot all the other components , lighting, etc. because I previously had an Outlaw Audio 950 that was popping like crazy. I have no hum or static and use a Monster Power Conditioner . I never did stop the 950 from popping so I sold it and got the Sherwood( which is amazing!). It is very quiet.

    I was actually kicking around the idea of trying an LSI9 as the center.
    Sharp Elite 70
    Anthem D2V 3D
    Parasound 5250
    Parasound HCA 1000 A
    Parasound HCA 1000
    Oppo BDP 95
    Von Schweikert VR4 Jr R/L Fronts
    Von Schweikert LCR 4 Center
    Totem Mask Surrounds X4
    Hsu ULS-15 Quad Drive Subwoofers
    Sony PS3
    Squeezebox Touch

    Polk Atrium 7s on the patio just to keep my foot in the door.
    · Share on FacebookShare on Twitter
  • scottnbnj
    scottnbnj Posts: 709
    edited March 2005
    Originally posted by wingnut4772
    I tried that with the LSI15 right channel and it sounds fine. I wonder what happened to the center? (and the old 15s for that matter). Oh well, new one is on the way !:)

    you calibrated and are set up for distance and everything...

    if the 15's placement is known to be good. maybe try taking the center out of the cabinet and placing it ,uh, carefully on top of the 15 (i guess with a towel or something between them) to see if you have the problem with the center outside of the cabinet.

    uh, i mentioned to be very careful. right?

    )
    · Share on FacebookShare on Twitter