a quick queston about modifying my polks

Options
goingganzo
goingganzo Posts: 2,793
edited May 2003 in Speakers
i want to upgrade to a better speaker but if i buld my own i need a new amp and if i get the new ls i need a new amp. my thought was to get the vifa ring tweet like usaed in the new ls line and install it in my 800i/400i what do you think? worthe the time or waste of time?
Post edited by goingganzo on
· Share on FacebookShare on Twitter

Comments

  • TonyPTX
    TonyPTX Posts: 545
    edited May 2003
    Options
    Possibly a waste of time unless you know how to redisign your crossover. You can't just throw some speakers in the box and hope that they work well together if the X-over isn't designed properly. Plus you're going to stick a 4 Ohm tweet in an 8 Ohm box. I wanted to do that a while back and had a post in the forum about it. It got ugly...
    Damn....8 lines...I've gotta put my sig on a diet now....
    · Share on FacebookShare on Twitter
  • goingganzo
    goingganzo Posts: 2,793
    edited May 2003
    Options
    i would not be that bad depends on how complex the xo is. it could be as easy as changeing 2 resistors i just want to know if it will fit.
    · Share on FacebookShare on Twitter
  • brettw22
    brettw22 Posts: 7,621
    edited May 2003
    Options
    Originally posted by goingganzo
    i just want to know if it will fit.

    For the guy that fully constructed his own subwoofer, I would think that the 'fit' question would be the last thing that would prevent you from doing something like this.......

    I remember Tony's thread about this, and I've called Ken at C.S. before to ask him if I could do the same with my RT16's and he flat out, and was almost offended at the question, said NO. I looked at the Vifa site and it didn't look like they had an 8 ohm ring tweeter, but they do have 8 ohm dome tweeters if I remember correctly.
    comment comment comment comment. bitchy.
    · Share on FacebookShare on Twitter
  • RuSsMaN
    RuSsMaN Posts: 17,987
    edited May 2003
    Options
    A forum member did do just this, and he had to modify the baffle on the RT series speaker slightly to make it fit.

    I personally wouldn't do it, but don't let the 4ohm rating scare you away, a 4ohm resistor in line with the tweeter will bring it to 8 ohm, if thats what the network is looking for.

    Cheers,
    Rooster
    Check your lips at the door woman. Shake your hips like battleships. Yeah, all the white girls trip when I sing at Sunday service.
    · Share on FacebookShare on Twitter
  • har_navalta
    har_navalta Posts: 957
    edited May 2003
    Options
    Not a good idea:confused: Tweaking the tweeters in your RT800i
    and CS400i or RT16 for vifa? WTH are you thinking...

    RT series speakers tweeters are made of Tri-Laminate Dome
    similar to the SL3000 materials.

    I, for one, still love the the sound of these tweeters. ;)


    Har
    · Share on FacebookShare on Twitter
  • TonyPTX
    TonyPTX Posts: 545
    edited May 2003
    Options
    Originally posted by RuSsMaN
    I personally wouldn't do it, but don't let the 4ohm rating scare you away, a 4ohm resistor in line with the tweeter will bring it to 8 ohm, if thats what the network is looking for.

    True, electrically this is sound, however sonically, you're robbing the power that the Vifa Ring Tweeter need to perform as is should. The true answer here is how do you get the whole rig down to 4 ohms. However, chances are, if you double the power to the speakers, they may go POOF....if you exceed the max wattage.
    Damn....8 lines...I've gotta put my sig on a diet now....
    · Share on FacebookShare on Twitter
  • goingganzo
    goingganzo Posts: 2,793
    edited May 2003
    Options
    the thing is i just want to try sothing different. i want to upgrade but i have a catch 22. i can upgrade my speakers but my amp wont handle the 4 ohm load so i have to upgrade my recever by adding a amp. i was looking at a diy setup useing the vifa tweet. it is a mtm setyp with a 8 in woof and the ring tweet. they look real nice. and have gotten rave revews.
    · Share on FacebookShare on Twitter
  • brettw22
    brettw22 Posts: 7,621
    edited May 2003
    Options
    Originally posted by goingganzo
    it is a mtm setyp with a 8 in woof and the ring tweet.

    HUH?!?!?!?!?!?!
    comment comment comment comment. bitchy.
    · Share on FacebookShare on Twitter
  • Frank Z
    Frank Z Posts: 5,860
    edited May 2003
    Options
    Originally posted by brettw22


    HUH?!?!?!?!?!?!

    ROFLMAO!!
    9/11 - WE WILL NEVER FORGET!! (<---<<click)
    2005-06 Club Polk Football Pool Champion!! :D
    · Share on FacebookShare on Twitter
  • Tour2ma
    Tour2ma Posts: 10,177
    edited May 2003
    Options
    Originally posted by TonyPTX
    However, chances are, if you double the power to the speakers, they may go POOF....if you exceed the max wattage.
    Highly unlikely... underpowered amps kill more speakers than over powered. Even our bass loving gonzo's ears will keep him from overdriving his speakers. Speaker ratings are continuous power ratings. They can handle three or four times their rating for transients.

    I tend to agree about just adding a resistor in series with the tweeter. With the current it sees halved its designed output would have to be reduced. Ditto the comment about the crossover not matching. But I have to go find that ugly thread you mention and see what the issue was there.

    Gonzo,
    If you want to mod your Polk's and they are out of warranty, why not try? You can go back to stock, if you don't like the results.
    Then again, you built your sub. Why not buld a pair of speaks from scratch?
    More later,
    Tour...
    Vox Copuli
    Better to remain silent and be thought a fool, than to open your mouth and remove all doubt. - Old English Proverb

    "Death doesn't come with a Uhaul." - Dennis Gardner
    "It's easy to get lost in price vs performance vs ego vs illusion." - doro
    "There is a certain entertainment value in ripping the occaisonal (sic) buttmunch..." - TroyD
    · Share on FacebookShare on Twitter
  • goingganzo
    goingganzo Posts: 2,793
    edited May 2003
    Options
    i wanted to get a listen to the tweet. i dont have a local dealer that sells the ls line. and the other problem is the speakers that use the ring tweet are usaly 4 ohms. so i have to upgrade the amp first


    this is the speaker type i was looking at
    http://www.t-3.cc/users/audioworx/page113Tibor-MTM.html
    · Share on FacebookShare on Twitter
  • Tour2ma
    Tour2ma Posts: 10,177
    edited May 2003
    Options
    ganzo, link didn't work, but I get the idea now. Did not intially think about the circuit impact of adding a 4 ohm tweet in parallel with an 8 ohm mid/bass. It would drop the apparent impedance to 2.67 ohm.

    Yup, amp time for you.
    More later,
    Tour...
    Vox Copuli
    Better to remain silent and be thought a fool, than to open your mouth and remove all doubt. - Old English Proverb

    "Death doesn't come with a Uhaul." - Dennis Gardner
    "It's easy to get lost in price vs performance vs ego vs illusion." - doro
    "There is a certain entertainment value in ripping the occaisonal (sic) buttmunch..." - TroyD
    · Share on FacebookShare on Twitter
  • goingganzo
    goingganzo Posts: 2,793
    edited May 2003
    Options
    here is a pic off the link i dont know the size. i am not too fond of the finish but this is a general look of the woofers and tweets.
    · Share on FacebookShare on Twitter
  • goingganzo
    goingganzo Posts: 2,793
    edited May 2003
    Options
    how come it is not ataching the pic?
    · Share on FacebookShare on Twitter
  • RuSsMaN
    RuSsMaN Posts: 17,987
    edited May 2003
    Options
    Link works fine for me.
    Check your lips at the door woman. Shake your hips like battleships. Yeah, all the white girls trip when I sing at Sunday service.
    · Share on FacebookShare on Twitter
  • burdette
    burdette Posts: 1,194
    edited May 2003
    Options
    In general, changing drivers in a speaker SYSTEM is not as easy as it is being made out to be, and rated nominal impedance of a different tweeter compared to the rated nominal impedance of the *system* or the woofer is hardly the overpowering concern. For a quality speaker system, the crossover design is an integral part of the design process for the entire system. It isn't just a matter of putting together an electrical crossover at some frequency and throwing in a couple of drivers that have the same impedance. For that approach, you might as well buy an off-the-shelf crossover... and if it were that easy, what the hell are we all doing throwing our money away on premade speakers from Polk or any other company?

    In fact, the Hi-Vi/Vifa design at that link has two drivers with different impedances.. the ring tweeter is 4 ohms nominal, the woofer is 8 ohms nominal. Those impedances, as well as many other characteristics of each driver.. voice coil inductance, DC resistance, etc. .. as well as adjustments such as a Zobel network, are all factored into the design from the very beginning.

    Parts Express has a featured design using the ring tweeter and a Vifa woofer. Perhaps that would be a good place to start if you want to utilize that tweeter, get into DIY beyond subs, AND to some extent add some assurance as to the result.

    http://www.partsexpress.com/projectshowcase/nebula/nebula.html
    · Share on FacebookShare on Twitter