Anthem Amp Right Channel

aiden
aiden Posts: 40
edited June 2010 in Troubleshooting
My Anthem MCA 20 amp right channel died yesterday!
Over the past month or so, when ever I powered down the system, I would hear a whistle come from my right front speaker! The whistle got lighter and lighter, then stop as the power left the system. Now, there is no sound at all coming from that channel. I know it's the amp, because I've switched speakers and amps to narrow it down to that amp channel.
I am not looking forward to sending it out to be repaired (time and money). Before I do, I want to ask around and get other people's opinions.
I have replaced the fuses inside ( two per channel). No luck! Is there other things I can look for? Or suggestions!
Thanks!!
Post edited by aiden on
· Share on FacebookShare on Twitter

Comments

  • dpowell
    dpowell Posts: 3,068
    edited May 2010
    It may be one of your caps that has gone bad. where you located?
    ____________________________________________________________

    polkaudio Fully Modded SDA SRS 1.2TLs + Dreadnaught, LSiM706c, 4 X Polk Surrounds + 4 X ATMOS, SVS PB13 Ultra X 2, Pass Labs X1, Marantz 7704, Bob Carver Crimson Beauty 350 Tube Mono Blocks, Carver Sunfire Signature Cinema Grande 400x5, ADCOM GFA 7807, Panasonic UB420, Moon 380D DAC, EPSON Pro Cinema 6050
    · Share on FacebookShare on Twitter
  • aiden
    aiden Posts: 40
    edited May 2010
    dpowell,
    I was just in contact with Anthem service and they said the same thing (cap)!!
    If I knew which one, I'd replace it myself.
    I'm a long way from sunny San Diego, Cal. Louisville, Ohio 7 mi. from Canton.
    I run a PRE2L also! Love it. Wish I had a Amp-2 in place of the MCA 20. Oh well one problem at a time.
    · Share on FacebookShare on Twitter
  • aiden
    aiden Posts: 40
    edited May 2010
    Is there a way to test the cap?
    · Share on FacebookShare on Twitter
  • dpowell
    dpowell Posts: 3,068
    edited May 2010
    How many caps in your amp? best practices is to replace both caps in a pair when one goes bad so that they are evenly balanced. Just replaced two in an RT3000 sub amp and Polk's recommendation was that both caps be replaced. See if Anthem can tell you where to get the replacements or if you can order directly from them.

    doug
    ____________________________________________________________

    polkaudio Fully Modded SDA SRS 1.2TLs + Dreadnaught, LSiM706c, 4 X Polk Surrounds + 4 X ATMOS, SVS PB13 Ultra X 2, Pass Labs X1, Marantz 7704, Bob Carver Crimson Beauty 350 Tube Mono Blocks, Carver Sunfire Signature Cinema Grande 400x5, ADCOM GFA 7807, Panasonic UB420, Moon 380D DAC, EPSON Pro Cinema 6050
    · Share on FacebookShare on Twitter
  • dpowell
    dpowell Posts: 3,068
    edited May 2010
    aiden wrote: »
    dpowell,
    I was just in contact with Anthem service and they said the same thing (cap)!!
    If I knew which one, I'd replace it myself.
    I'm a long way from sunny San Diego, Cal. Louisville, Ohio 7 mi. from Canton.
    I run a PRE2L also! Love it. Wish I had a Amp-2 in place of the MCA 20. Oh well one problem at a time.

    The Pre2L is great! I have it running temp duty in the home theater while my AVR is being fixed. It sure adds a nice sound!
    ____________________________________________________________

    polkaudio Fully Modded SDA SRS 1.2TLs + Dreadnaught, LSiM706c, 4 X Polk Surrounds + 4 X ATMOS, SVS PB13 Ultra X 2, Pass Labs X1, Marantz 7704, Bob Carver Crimson Beauty 350 Tube Mono Blocks, Carver Sunfire Signature Cinema Grande 400x5, ADCOM GFA 7807, Panasonic UB420, Moon 380D DAC, EPSON Pro Cinema 6050
    · Share on FacebookShare on Twitter
  • aiden
    aiden Posts: 40
    edited May 2010
    dpowell,
    It looks like one of the caps has a loose or broken connection to the board. I'm going to try to solder it later to night. I'll let you know if it works!! By the way, there's three caps per channel, 100V 100uf.
    · Share on FacebookShare on Twitter
  • dpowell
    dpowell Posts: 3,068
    edited May 2010
    Interesting. Replacement caps from Polk CS ran around $13 each. Not sure what they were rated at.
    ____________________________________________________________

    polkaudio Fully Modded SDA SRS 1.2TLs + Dreadnaught, LSiM706c, 4 X Polk Surrounds + 4 X ATMOS, SVS PB13 Ultra X 2, Pass Labs X1, Marantz 7704, Bob Carver Crimson Beauty 350 Tube Mono Blocks, Carver Sunfire Signature Cinema Grande 400x5, ADCOM GFA 7807, Panasonic UB420, Moon 380D DAC, EPSON Pro Cinema 6050
    · Share on FacebookShare on Twitter
  • aiden
    aiden Posts: 40
    edited May 2010
    I've done a little soldering to the loose cap connection and also glued the plastic top to the speaker connection to the right amp channel. the plastic was not connected to the metal screw done. I am back with sound in both channels, but still has the whistling sound (coming from the right speaker) when powering down!? All other channels are fine, just that one makes a continuing whistling sound till the power is out of the channel.
    Is that the cap going or something else?
    · Share on FacebookShare on Twitter
  • ViperZ
    ViperZ Posts: 2,046
    edited June 2010
    aiden wrote: »
    I've done a little soldering to the loose cap connection and also glued the plastic top to the speaker connection to the right amp channel. the plastic was not connected to the metal screw done. I am back with sound in both channels, but still has the whistling sound (coming from the right speaker) when powering down!? All other channels are fine, just that one makes a continuing whistling sound till the power is out of the channel.
    Is that the cap going or something else?

    Replace that cap for sure. Actually, as already suggested, replace the same cap in another channel too.
    Panasonic PT-AE4000U projector for movies
    Carada 106" Precision Series (Classic Cinema White)
    Denon AVR-X3600H pre/pro
    Outlaw 770 7-channel amplifier
    B&W CDM1-SE fronts
    B&W CDM-CNT center
    B&W CDM1 rears on MoPADs
    JBL SP8CII in-ceiling height speakers
    Samsung DTB-H260F OTA HDTV tuner
    DUAL NHT SubTwo subwoofers
    Oppo BDP-93 Blu-Ray player
    Belkin PF60 Power Center
    Harmony 1100 RF remote with RF extender
    Sony XBR-X950G 55" 4K HDR Smart TV + PS3 in the living room
    · Share on FacebookShare on Twitter
  • heiney9
    heiney9 Posts: 25,165
    edited June 2010
    I think the trouble shooting section is for POLK PRODUCTS, not just every gear problem. Certainly post your gear issues, but perhaps in the electronics or 2 channel section. I've noticed a lot of random posts here.

    The intent is for customers to get a dialog going if they are having issues with a POLK branded product.

    Just food for thought.

    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!
    · Share on FacebookShare on Twitter
  • aiden
    aiden Posts: 40
    edited June 2010
    Thanks for the heads up heiney9. I'll know better next post!
    I'm going to replace the caps ViperZ.
    · Share on FacebookShare on Twitter
  • dpowell
    dpowell Posts: 3,068
    edited June 2010
    Let us know how it turns out.
    ____________________________________________________________

    polkaudio Fully Modded SDA SRS 1.2TLs + Dreadnaught, LSiM706c, 4 X Polk Surrounds + 4 X ATMOS, SVS PB13 Ultra X 2, Pass Labs X1, Marantz 7704, Bob Carver Crimson Beauty 350 Tube Mono Blocks, Carver Sunfire Signature Cinema Grande 400x5, ADCOM GFA 7807, Panasonic UB420, Moon 380D DAC, EPSON Pro Cinema 6050
    · Share on FacebookShare on Twitter