Why does my gfa-535 do this?

nadams
nadams Posts: 5,877
edited December 2006 in Electronics
Just wondering if this is normal... When I turn the power off on my 535, the power light slooooowly dims to nothing. All the while, the amp is still driving the speakers. When the light finally goes out, the left channel dies first into static, then the right channel dies. Here's a video-

http://www.king-nerd.com/dood/temp/100_2925.mov

The way I found out about this, is that apparently my pre-amp receiver does something similar through the pre-outs, except that it outputs a descending sine wave to the amp, which really sounds nasty on the speakers. So, I have to make sure that the amp is fully off before turning the preamp off at all.

Is this just normal? Just the caps taking a long time to discharge? I've never had separates before, so I honestly dont' know...
Ludicrous gibs!
Post edited by nadams on
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Comments

  • venomclan
    venomclan Posts: 2,467
    edited December 2006
    My 535 does the same thing. It actually lets out a weird...****-like noise. I have it switched by my power conditioner on a delay. The delay is not long enough and the amp lets out its final wimper lol. Still going strong though.
    Venom
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  • nadams
    nadams Posts: 5,877
    edited December 2006
    Just wondering, as this amp was very well used when I got it. I wasn't sure if it was normal, or if the relay circuit was broken. But no! It can't be broken if it doesn't exist :). Thanks guys...
    Ludicrous gibs!
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  • danger boy
    danger boy Posts: 15,722
    edited December 2006
    Noah, thanks for the movie. i ate a whole bag of popcorn waiting for your amp to shut down. Waaaaaaaaaaa.

    JK!

    My Adcom GFA-5400 does it too.. doesn't take quite that long. but sounds like it's normal though.
    PolkFest 2012, who's going>?
    Vancouver, Canada Sept 30th, 2012 - Madonna concert :cheesygrin:
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  • heiney9
    heiney9 Posts: 25,217
    edited December 2006
    Completely normal and it's been discussed (by me) in several threads before :) . Adcom uses no current limiting circuits or devices and no output muting relays of any kind. The simple is better approach. So what you are hearing is the normal draining of the caps. I usually turn the amp off first and wait for the light to go completely dim and wait a few more seconds and then turn off the pre. You may also experience a slight thump when powering up, totally normal as well. Absolutely no harm will come to the speakers or amp. I;ve had my Adcom for close to 20 years and until recently my Polk RTA-11's for the same period of time and had ZERO problems.

    Again typical relays and current limiting devices add noise and clutter to the circuitry and Adcom feels these items are not needed and will degrade sound. There are internal rail fuses as well as power line fuses to protect in the case of malfunction.

    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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  • ben62670
    ben62670 Posts: 15,969
    edited December 2006
    I have the GFA-555, 5400, 585, and 7500 same same same same no problems, except explaining that it is normal to the non hi fi crowd :-)

    Enjoy Ben
    Please. Please contact me a ben62670 @ yahoo.com. Make sure to include who you are, and you are from Polk so I don't delete your email. Also I am now physically unable to work on any projects. If you need help let these guys know. There are many people who will help if you let them know where you are.
    Thanks
    Ben
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  • dudeinaroom
    dudeinaroom Posts: 3,609
    edited December 2006
    my 555 does the same thing, it's not as bad it you use good cable management
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  • danger boy
    danger boy Posts: 15,722
    edited December 2006
    dudeinaroom wrote:
    my 555 does the same thing, it's not as bad it you use good cable management


    So you're saying the rest of us suck at cable management? Is that what i'm reading here??? :eek: :p;)
    PolkFest 2012, who's going>?
    Vancouver, Canada Sept 30th, 2012 - Madonna concert :cheesygrin:
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