rebuilt crossovers in monitor 7A sound level

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danger boy
danger boy Posts: 15,722
edited July 2007 in DIY, Mods & Tweaks
A few weeks ago my friend helped me rebuild the crossovers in a pair of monitor 7A's.. once they were finished, they sounded great. much more detailed and revealing. They still sound great. except that the volume is louder on one speaker then the other speaker.

I have swapped it around.. and the volume level follows the speaker... so I know it's not an amp or pre amp issue. Plus i've tried a different pair of speakers in this system with good results.

What could be the problem with one speaker having more volume than the other, or is one speaker more quiet than the other..

all drivers are in good condition.. no tears or rips, all drivers are well sealed in the cabs.

the only thing that looks different is that one passive looks like the surround isn't as beefy as the surround on the other speaker.. I'll pull them and see if they are identical. Do passives even have model numbers on them?

it's odd, because i have to compensate for the off levels by turning down the loud speaker at the amp.. so that they both match volume wise.

I played around with placement too.. although it didn't help with the volume problem.. it really did help with soundstage and depth of the music.. they really sound sweet now. Placement is very crucial. ;)
PolkFest 2012, who's going>?
Vancouver, Canada Sept 30th, 2012 - Madonna concert :cheesygrin:
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  • heiney9
    heiney9 Posts: 25,092
    edited July 2007
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    What components did you use? Perhaps one of the caps or resistors is not the same value as the other (out of tolerence). If they were Solens or Sonic Cap and Mills that probably isn' the case, but it does happen once in awhile.

    Also recheck all the connections and make sure all the new parts went where they were supposed to.

    H9
    "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!
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  • danger boy
    danger boy Posts: 15,722
    edited July 2007
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    i used Solens caps and Mills resistors and they were the same value. that's what makes me think it's a driver issue. if it was just ever so slight... i could live with it.. but since it's to noticeable, i have to fix it.

    I may try and swap out some spare drivers and see what the results are.
    PolkFest 2012, who's going>?
    Vancouver, Canada Sept 30th, 2012 - Madonna concert :cheesygrin:
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  • RuSsMaN
    RuSsMaN Posts: 17,987
    edited July 2007
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    Pull the drivers and check the dc resistence on each with a multimeter. They should be within half an ohm of each other, or yes - they may play at different levels.

    You noticed the issue after the upgrade, right? I gotta go with H9 that something isn't wired, isn't wired properly, or is out of spec.

    Cheers,
    Russ
    Check your lips at the door woman. Shake your hips like battleships. Yeah, all the white girls trip when I sing at Sunday service.
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  • danger boy
    danger boy Posts: 15,722
    edited July 2007
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    yeah i noticed the issue after the upgrade.. they were DOA before.
    PolkFest 2012, who's going>?
    Vancouver, Canada Sept 30th, 2012 - Madonna concert :cheesygrin:
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  • heiney9
    heiney9 Posts: 25,092
    edited July 2007
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    If they were DOA before, had you ever heard them play? Still could be a driver/tweeter issue. If they were DOA they might have cooked one of the tweets too. The thing is with the Monitor series the tweets go pretty low for a traditional tweet so I'd look there first before tearing into the x-over.

    If they were fine before you re worked the x-over then had this issue I'd be inclined to say it's a x-over issue. Not so sure now. If it turns out the peerless is toast, that's a shame.

    H9
    "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!
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  • danger boy
    danger boy Posts: 15,722
    edited July 2007
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    i should explain the deal so we're all up to speed.

    I bought these DOA 7A's from a coworker.. they had two blown Peerless tweeters, one blown/frozen MW6500 mid driver, and a blown cap in one of the crossovers.

    I pulled and tested all the drivers, that's how I came to the conclusion that some of the drivers were toast.

    I got a Peerless tweeter from a club member and bought two used MW6500 drivers. so putting them all back together, we replaced both tweeters and one mid bass driver along with upgrade both crossovers with the Mills/Solens parts.

    Now the volume on one speaker is louder than the other. both sound great on their own, but together, one is slightly louder than the other.

    I paid $20 for them.. knowing they had problems of some kind before i got them. He was just going to throw them out.. so they were rescued from the big speaker dumping ground in the sky.;)
    PolkFest 2012, who's going>?
    Vancouver, Canada Sept 30th, 2012 - Madonna concert :cheesygrin:
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  • fredv
    fredv Posts: 923
    edited July 2007
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    I experienced the same symptom with my Monitor 5B. It turned out one of the SL2000 somehow was a couple dB louder than the other. Try swap the tweeters to see the difference follows.

    -fredv-
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