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How do I find a replacement transformer for my subwoofer?

The speaker hums when power is applied (no audio input). The only info I can provided is from the top of the transformer. PT005V076UA Ferderal B3-033-2-76-F Built in Thermal Fuse. A search on the internet was unfruitful. The manufacturer could not provide any assistance.

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The transformer is fine its the amplifer probably has dried up electrolytic capacitors usually a speaker has one capacitor to rework the audio levels and emphasis for the tweater
it wont be the transformer/speaker for sure
and for sure its the amp

try another amplifier or replace your ones capacitors

Posted on Nov 28, 2014


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SOURCE: Acoustimass Subwoofer has a low "hummm" sound when turned on.

Sounds like an inadequate ground wire in the signal cable. You may have to replace the cable between the reciever and bass module. It also, however, may be IN the bass or reciever module.

Posted on Aug 05, 2008

  • 1 Answer

SOURCE: PAradigm ps-1000 subwoofer

It turns out its most likely one of the resistors on the PCB on the amplifier plate.

My uncle has had the same problem and managed to replace the resistor and its working as normal now.

Posted on Nov 02, 2008

  • 5 Answers

SOURCE: loud humming buzzing sound coming from subwoofer

make sure you have the speaker connection right if you do then it is a ground problem try plugging it in a different outlet

Posted on Dec 16, 2008

  • 2 Answers

SOURCE: connect powered subwoofer

  • If your receiver has a dedicated subwoofer line level output, we recommend connecting your subwoofer to this jack. Most receivers will have just one (mono) subwoofer output, while quite a few subs require two inputs. You can use an RCA "Y" adapter cord , which is a cable with one female RCA jack at one end, and two male RCA plugs at the other. Some receivers require menu settings (such as "sub-on" or "front speakers-small") that must be made before the sub output will be active.

  • Posted on Jan 07, 2009

    • 1 Answer

    SOURCE: subwoofer eating fuses.

    Check the circiut board for any blown capacitors. Sometimes it's that simple as replacing a capacitor. But then again, what is causing the capacitor to blow??/ Hope this helps.

    Posted on Aug 01, 2010

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    This is a nice speaker. You could get humming from the wires being crossed they actually do have polarity and better speakers will hum if the wires are crossed. The volume cloud also be too high without input. You also may have some interference with other audio wires or power wires close to the speaker.

    Apr 05, 2014 | ElectroVoice . Speaker

    1 Answer

    After a power outage I have a loud hum.

    Hi, The Ground Rules Of all the annoyances that can afflict any audio/video home theater or even a simple stereo installation, the notorious "ground loop" may well be the most difficult and persistent one to track down and eliminate. A "ground loop" is caused by the difference in electrical potential at different grounding points in an audio/video system. (All the grounds in an A/V system should ideally be at "0" potential.) A ground loop typically adds a loud low-frequency hum or buzz as soon as you plug in any of various audio or video components, including subwoofers, cable-TV outboard boxes, satellite-TV feeds, TV displays, amplifiers, A/V receivers or turntables. The buzz/hum is a byproduct of the multiple power supply cables and a ground voltage differential within your system and its network of interconnecting cables.

    Here are some methods to help you get rid of ground loops. Try these first and don't waste money on a power "conditioner" which, in most cases, won't help. (There is no need to "condition" the AC power for your system. Your receiver or amplifier already has a power supply with its own filters and transformers. No further filtering is normally required.)

    If you get your system up and running and hear an audible buzz or hum, the first culprit to look at is either the powered subwoofer or your cable-TV or satellite-box feed at the entry point to your system.

    First, the subwoofer: unplug the coaxial cable that connects to your powered subwoofer to see if the ground-loop hum disappears. If it does, it's likely coming in through your cable/satellite TV feed.

    Reconnect your subwoofer's coaxial cable from the subwoofer input to your receiver's subwoofer output and disconnect the cable-TV feed (or satellite feed) from your outboard set-top cable box or satellite tuner. Be sure and disconnect the cable before any splitters. Now see if the hum/buzz from your subwoofer stops.

    If that eliminates the hum, you can install one of these inexpensive in-line ground isolators from Parts Express or Bass Home. Note that these transformer-based ground isolators will work fine with analog cable-TV feeds, but depending on their design they may interfere with or block reception of HDTV signals via a digital cable or satellite dish feed.

    Install the ground isolator between the cable-TV feed and the input of your outboard cable-TV box or satellite tuner (or the TV display's antenna or cable input if you have a set with a built-in TV tuner or a cable-card ready set). In many cases, the ground isolator will "break" the loop and remove the annoying hum or buzz by isolating the TV-cable ground.

    If a hum remains with the TV cable completely disconnected from your system, or you don't want to risk degrading reception of HD signals from a cable or satellite system, then you may have to add a ground isolator like this Radio Shack Model 270-054 between the line-level coaxial subwoofer cable from your A/V receiver and the line-level input jack on your powered subwoofer.

    In all cases, if your subwoofer has a ground-lift screw like some of Axiom's subwoofers, try first removing the screw (or replacing it) to see if it increases or eliminates the hum. It may or may not make a difference.

    If you do not have easy access to the aforementioned ground isolators, here are a few more tips:

    Try plugging the subwoofer into a different AC outlet in the room, one that isn't supplying power to your components (A/V receiver, TV, cable box, etc.). That might fix it.

    Try reversing the AC plug for your A/V receiver or the powered subwoofer. If it's a 3-wire plug or a polarized plug, which has one prong wider than the other, you won't be able to reverse the plug. For safety, do not use a "cheater plug" to bypass the 3-wire plug.

    With the power OFF, reverse the AC plugs one by one of any other components that have a standard 2-prong AC plug that isn't polarized. Each time you reverse a plug, turn on the system with the attached component and your subwoofer and see if the hum disappears. In some cases, reversing one or more plugs will eliminate the hum.

    If you have a turntable, try connecting a separate ground wire to a chassis screw on your preamp or receiver and see if the hum disappears. If you already have a turntable ground wire, try removing it from the preamp. One or the other may eliminate the hum.

    Finally, here is another solution that worked well for a member of our message boards who decided to discard his ground-loop isolator on his subwoofer: "I took off the ground-loop isolator I'd been using and connected a plain 14-gauge wire to chassis screws on the sub and the receiver then powered everything on. Although hum was still there, it was far lower than before. Next I unscrewed the ground-loop screw on the back of the sub and that took care of the hum completely."

    Almost certainly sounds like an earth loop to me, but can be caused by a poorly made transformer or phase shifts on the mains supply. Visit some power conditioner web-sites like Isotek or Isol-8 (or google "earth loop") where there's plenty of advice on how to reduce/eliminate earth loops and other causes of mains-induced hum (transformer problems etc).

    Hum on the speakers usually indicates that there is a DC voltage on the speaker line. DC voltage on the output lines would be caused by a shorted output transistor.

    Have a nice day...

    Feb 16, 2011 | Cambridge Soundworks BassCube 12 Speaker

    1 Answer

    My Sony model SS-MSP1 , SA-WMSP1 , AC120V , 60HZ , 50W hums.

    If it hums on the audio side on all channels it might be the 60hz mains hum getting through. This is caused by the failure of the large Electrolytic capacitors in the power supply.
    Another cause of hum (not in the audio) is the transformer. Also parts that hum should be replaced. If you can't pin down a huming part IE where it is. Then use a drinking straw as a stethoscope, by putting one end in your ear and the other over the PC board.

    Feb 14, 2010 | Sony Audio Players & Recorders

    2 Answers

    Have the KLH ASW10-120 Powered Subwoofer and it is blowing fuses

    If it stays on for 3 seconds then it probally is not the transformer. However it may very well be the power amp no way to tell untill we operate. Call Pro Line Music 215-736-8055

    Dec 11, 2009 | KLH ASW10-120 Subwoofer

    1 Answer

    Sub has started humming with amp turned off. just turned on at wall switch.nothing running

    If the hum is from the back of the unit around the amplifier, it may be the transformer. It could be that the mounting is loose.
    It could also be that the transformer is going out.

    Disconnect all the inputs to the unit, Still hum?

    If the hum stops you have something causing noise to the input.

    If you have it on a switched circuit, try moving the power plug to a different outlet that is not on a switch. If hum stops, then you have something on that circuit causing the problem

    if all inputs are disconnected and it still humms good chance it is the transformer.

    Nov 12, 2009 | Velodyne CHT-8 Subwoofer

    5 Answers

    Subwoofer making load humming noise

    The reason for the hum in the Altec Lansing VS4121 speaker system is the stray field of the power supply transformer. This stray field is strong enough to affect the amplifier. All other reasons given by numerous reports on the web do not apply. If you are handy and have got the time you may mitigate the problem by physically moving the amp away from the power supply or turning it 90 degrees. I managed to lift up the amp in my subwoofer by about 50 mm, which was difficult to achieve and did not cure the problem perfectly. I don't see any other way to solve this problem except you feed DC in from the outside and do not use the internal power supply. That would be really odd indeed

    Gerhard Weber.

    Jan 29, 2009 | Altec Lansing VS4121 Speaker

    2 Answers

    Subwoofer probelm

    I suspect you have a bad cable, a poor ground or a bad
    power supply inside the speaker amplifier. The amplifier
    (inside the sub-woofer) could also be defective.
    1) Bad cable or connector:
    If the (braided shield/outer tube) of the coaxial input cable is
    not grounded, the cable will pickup line frequency "hum"
    from surrounding power lines, house wires, lights and

    This hum is then amplified by the speaker's amplifier
    causing the constant bass sound you speak of.

    Because the hum frequency fundamental is 60 Hertz in
    North America, 50 Hertz in Europe, you hear it coming
    mostly out of the sub-woofer, because the midrange and
    high speaker circuits filter it out.

    Check the input connectors, cable at both ends, wiggle
    the jacks at a low volume setting to see if it changes.

    Make sure that you are indeed using a properly shielded
    coaxial cable.

    A coaxial cable consists of a thin inner conductor, surrounded
    by a flexible tube made up of a braided metal shield, which
    must be grounded. This prevents hum from being picked up
    by the sensitive amplifier inputs.

    2) If the power supply within the sub-woofer's internal amplifier
    is defective, the the power supply hum will also get coupled
    into the amplifier and speaker with same results as above.

    Power supply hum is typically twice the line frequency,
    i.e. 120 Hertz, but not always, depending on what
    component failed: Rectifier diode, filter capacitor, or
    the voltage regulator.

    3) Ground loops:
    When you run very long cables between the source and
    destination of an audio signal, multiple ground paths (must)
    exist between the two points in space, creating complete
    loop circuits.

    Power line hum from the environment can (will) induce
    heavy AC currents around these loops, creating a voltage
    gradient across these cables, and in-between the end

    Once again, this AC hum is coupled into the amplifier inputs.

    Ground loops become a problem with cables over 10
    feet long, and an astronomical problem for stage audio
    engineers. To avoid ground loops, they must break
    the circuit's continuity by using isolation transformers,
    optical isolators, and/or differential input amplifiers.

    So how long are your cables?

    Most house stereo components are only designed to
    handle 6 to 10 feet of cabling max.

    30 feet is already asking for major trouble.

    4) Feed back oscillation: This occurs when the output of
    an amplifier is fed back to the inputs with a round trip
    gain greater or equal to unity. The tiniest little electrical
    disturbance is then amplified and re-amplified, over and
    over again, usually at one preferred frequency, causing
    the typical (ear-splitting) microphone squeal or howl.

    In your situation feedback and/ loss of original signal
    could be the result of mis-wiring the input cables.

    Note that this is NOT as silly nor as unlikely as it sounds,
    because many computer audio cards and even some
    home stereo systems have re-configurable inputs and

    SOFTWARE configuration decides which jack at the
    back does what !!!!

    On my computer, for example, the Realtek audio driver
    tries to automatically figure out what cable is connected
    to each jack (usually it gets it wrong)

    Using the Realtek control panel applet, I can then
    manually re-configure the gray jack as input,
    the green jack as bass, pink jack as center.... etc.

    If this situation also applies to your system, please check
    the software configuration. Connecting an output cable to
    an input jack will certainly cause a lot of HUM and not
    much music.

    5) Finally, don't rule out internal sub-woofer failure. Unlike
    the passive stereo/hi-fi speakers of days gone by, modern
    multi-channel theater systems with front, center, rear and
    sub-woofer speakers are internally amplified, with active
    frequency cross-over filters and special effect/ surround
    sound capabilities.

    Usually, the large sub-woofer contains most of the
    electronics, amplifiers and filters.

    It feeds the other speakers, and it is controlled by
    an external volume control module which can be separate
    or built into one of the tweeters.

    These sub-woofer electronics are prone to poor design,
    overheating and early failure. (Even fresh out of the box
    like yours)

    If you cannot get it working, take it back to the store,
    and make the NICE salesmen **** with it.

    Good luck
    Please rate my answers

    Jul 20, 2008 | Yamaha 5.1-Ch. Surround Sound Home Theater...

    1 Answer

    Loud hum on subwoofer.

    try another speaker on that channel if you get no sound or it hums then it is time to take your set to a tech your audio out put on that side is damage along with some caps.good luck.

    Mar 30, 2007 | Polk Audio RT1000I Speaker

    1 Answer

    Subwoofer hums under power not hooked to system & hooked up?

    This may or may not apply to your particular problem. On similar humming sound problems, I normally would look for either a fault in the input side and/or a leaky/defective capacitor in the power supply. On the input side, this may be a frayed shielded wire, loose connector (esp. the outer which is normally the ground). Try completely removing the connecting/input cable that goes into the subwoofer. If that doesn't work, then it you may want to check the big capacitor in the power supply section of the subwoofer. If you are not that familiar in working with power supplies, may I suggest that you ask any electronic technician to have a look at it since capacitors store a rather hefty voltage. Better be on the safe side. Hope this works out ok with you

    Mar 11, 2007 | Harman Kardon Harmon Kardon SoundStick II...

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