What does clipping mean?

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  • 09-02-2005, 04:49 PM
    L.J.
    What does clipping mean?
    Read this term a couple of times today. Doesn't sound like a good thing. Can anyone explain what it means. Thanks
  • 09-02-2005, 05:05 PM
    kexodusc
    Clipping basically happens when an amplifier is asked to deliver more current to a speaker than the amp is capable of doing. When the amp goes into clipping (if that's the proper terminology), it "clips" or "cuts" off the tops and bottoms of the musical waveforms that it's trying to reproduce, hence you get the term "clipping".

    You're right..it's not a good thing...it = distortion. Usually heard as a crunching sound on musical peaks. Might be described as crackling instead of crunching, but you'll know it when you hear.

    Clipping is bad, mmmkay?
  • 09-02-2005, 05:07 PM
    GMichael
    Quote:

    Originally Posted by L.J.
    Read this term a couple of times today. Doesn't sound like a good thing. Can anyone explain what it means. Thanks

    Sound is a series of waves. When there isn't enough power to complete the tops and bottoms of the waves, clipping happens. The waves get "clipped" off.
    This is just the simple explanation. Others here know more than I do and can fill you in more. But that's the jist of it.
  • 09-02-2005, 05:26 PM
    markw
    A speaker can "clip" also.
    A speaker moves in and out only so far. That's when it's handling just about as much power as it can handle without sounding bad and this is generally frequencty dependent in that lower feequencies require more movement than high frequencies.

    The back side of the speaker, or the "stop" is the limiting factor here. When it hits it, it sounds scary awful.

    If you feed it too much power, while it may not blow the voice coil*, thereby instantly silencing it, it very well may hit that "stop" at the back of the speaker. An occaasional hit might not do permanant damage but persisting in it may.

    Again, isf something sounds bad, turn it down ...NOW!

    *unfortunately, this is what manufacturers tout when posting specs.
  • 09-02-2005, 05:42 PM
    L.J.
    Another quick question if anyones listening. When I listen to digital music through cable (comcast) I have to turn my Denon 2805 up pretty high to get it sounding good. Is there a problem with that. My mains are Energy C-9's. My volume range is -80 to 8. I usually gotta go to 00 to get it loud. There's no distortion, so I'm wondering is it ok to go this high on the volume. My cable audio runs to my avr via fiber optic. The f. optic cable is about 6 ft long.
  • 09-02-2005, 09:23 PM
    topspeed
    The volume number on your Denon is completely arbitrary. It means nothing. As long as you stay below distortion, you'll be fine.
  • 09-03-2005, 12:50 AM
    EFE Speakers
    What does clipping mean?
    It means a 20 yard penalty and loss of a down!


    Sorry, I just couldn't resist!

    (( ;

    EFE
  • 09-03-2005, 02:50 AM
    kexodusc
    Quote:

    Originally Posted by markw
    A speaker moves in and out only so far. That's when it's handling just about as much power as it can handle without sounding bad and this is generally frequencty dependent in that lower feequencies require more movement than high frequencies.

    The back side of the speaker, or the "stop" is the limiting factor here. When it hits it, it sounds scary awful.

    If you feed it too much power, while it may not blow the voice coil*, thereby instantly silencing it, it very well may hit that "stop" at the back of the speaker. An occaasional hit might not do permanant damage but persisting in it may.

    Again, isf something sounds bad, turn it down ...NOW!

    *unfortunately, this is what manufacturers tout when posting specs.

    Just an add-on...What you're describing I often hear referred to as a woofer bottoming out as well - usually you'll hear lead-slap as a warning.

    Markw is absolutely right. Power handling is rated by electrical capacity of the voice coil usually. The true mechanical power handling is often much lower and harder to predict. Another good reason for using your receiver's crossover to send bass only to the subwoofer!!!
  • 09-03-2005, 06:18 AM
    markw
    true. I've heard both terms used to describe this phemomona
    Quote:

    Originally Posted by kexodusc
    Just an add-on...What you're describing I often hear referred to as a woofer bottoming out as well - usually you'll hear lead-slap as a warning.

    ...although "bottoming out" is more technicaly correct.
  • 09-03-2005, 06:27 AM
    L.J.
    Thanks for the info and quick replies guys. I've been reading alot of past threads and I'm learning so much.
  • 09-03-2005, 11:10 AM
    EFE Speakers
    Ok, I'll be more serious this time around! (( ;

    Clipping?

    Solid state amplifiers use switching transistors on their output stage that feeds current to the speakers.

    These transistors feed current (measured in watts) to the speakers by switching off and on very fast, slower switching when the volume is down and faster switching when the the volume is up. When you turn the volume up to a point where the transistors can no longer produce more current (sort of like an engine hitting its max rpm), the switching starts to go wacko (distortion) and if you continue at that level eventually the transistors lock up and send tons of direct current (DC) to the speakers thus burning the voice coils out like a burnt fuse.

    DC is the enemy and destroyer of speakers, so you want to avoid clipping by all means. If you understand how this works, you'll understand that a small receiver or low powered amp will clip long before a more powerful amp, because it is easier to hit its limit quicker.

    Some people think if they have speakers that are rated at 300watts and a little 50 watt per channel receiver operating them, the chances of burning the speakers out is less, but it's just the opposite! A small receiver will burn out speakers much easier, because as you turn the volume up, clipping will occur much quicker!

    Additional info to this thread.
    Larger or more powerful amplifiers use higher current transistors and/or more of them for each channel to produce more current. They also use heavier transformers in the power supply to give the extra power needed to the output stage, basically a beefed up circuit from input to output. Some amps have soft clipping circuits built-in, this is basically a limiting circuit to prevent full on clipping and DC from occuring. There are other types of solid state amps that use non-switching outputs, known as pure "Class A", but I won't go into them or tube amps since the question revolves around normal ss amps which are about 90% of what most people have.

    Speakers can often take much more power than they are rated if operated by a very clean high powered amplifer. Avoiding clipping and feeding more current to drivers controls them better and clean power allows the maximum performance from speakers. Clean high current gives the speakers better dynamics, first because it sends a higher amount of clean current to the driver instantly, but it also does the reverse and stops the driver from moving when the signal stops. A higher dampening factor is usually found in good high powered amps. A speaker driver is basically an electromagnetic piston. The more instantaneous current you can feed and remove from that piston, the quicker it will react and thus cleaner more dynamic speakers. This is why subwoofers with high powered amps (250 to 500watts) sound cleaner, tighter and more natural, compared to slow mushy bass from a low powered sub.

    More available current on demand simply equates to cleaner sound whenever one is listening at louder volume levels, and often at lower levels also, especially when lots of bass content is in the music.


    Example: Using a 300 watt amp on a pair of 100 watt rated speakers can play much louder and much cleaner than can a 50 watt amp operating a pair of 300 watt speakers.
    The only problem (and it really isn't a problem) with using a clean high powered amp is, the speakers will sound clean all the way up until they go silent (burn out). There usually is no warning such as distortion unless the drivers bottom out as has been mentioned in earlier postings. Since very high powered amps seldom hit the point of hearing distortion, your speakers may not give you any warning they are at their limit until it is too late.

    There is much debate on which way to go, but it is my opinion to buy lots of extra power even if you don't have the environment to use it. Having high current on demand makes speakers sound better (more control) and have a far less chance of clipping!
    Hope this explanation helped, thanks!

    Ed Frias
    EFE TECHNOLOGY Speakers
  • 09-04-2005, 06:05 AM
    twochannelsonly
    oh boy a real question that means something
    I guess alot of us take it for granit and know all the answer's ... LOL

    Noun: clipping kliping
    An excerpt cut from a newspaper or magazine
    "he searched through piles of letters and clippings"
    - newspaper clipping, press clipping, cutting, press cutting

    Cutting down to the desired size or shape
    - trim, trimming

    The act of clipping or snipping
    - clip, snip
    Verb: clip (clipped,clipping) klip
    Sever or remove by pinching or snipping
    - nip, nip off, snip, snip off

    Run at a moderately swift pace
    - trot, jog

    Attach with a clip
    "clip the papers together"

    Cultivate, tend, and cut back the growth of
    - snip, crop, trim, lop, dress, prune, cut back

    Terminate or abbreviate before its intended or proper end or its full extent
    - curtail, cut short


    Derived forms: clippings

    Type of: attach, cut, cutting, cutting off, excerpt, excerption, extract, run, selection, shorten, thin out

    Antonym: unclip

    Encyclopedia: Clip

    Clipping

    And if all that doesnt help click the link below. ;)

    Click here for great clipping read
  • 09-08-2005, 08:32 PM
    sam9
    For clarification clipping can happen even if limitless current is available. An analog audio signal is represented by voltage vs. time. The maximum aplitude is determined by the +/- voltages available from the power supply. If a +40 volts and -40 volts are avaialable a signal amplitude from peak minus to peak plus of 80V can be respresented. This in directly analogous to the the motion of the loudspeaker and a soft sound will only require a few volts while very loud sounds may require the entire range. If the peak voltage that is required to a give sound peak is greater than the voltage available the signal form witll look clipped off on an oscillioscope. Small to modest amounts of clipping often go unnoticed.

    Current gets involved in this because if the power supply does not provide enough current as well as voltage, clipping will also ocurr but at a lower voltage. I.e., the peak voltage otherwise available from the power supply will not be available. This get complicated because of Ohm's law where Voltage = Current x impedance. The impedance in this case is the the impedance of the loudspeakers. You can see that a 4 -ohm speaker requires twice as much current from the amplifier and power supply as as an 8-ohm loudspeaker if the same peak voltage is to be attained. Still more complicated is that these impedance ratings are only "nominal" -- in real life the impedance depends on the the frequency of the signal. A typical "8-ohm" speaker bay actually have an impedance from 20-ohms to 2-ohms depending on the frequency of the signal. The current required can vary drasticly over a fraction of a second.

    It is fairly straight forward to determine what is needed in a power supply to provide enough current so that current does not become a limiting factor. However, there is a price to pay for that in terms of size, wieght and expense. There is also another limitation and that is the maximum current the output devices can handle without being destroyed. While it is possible to use so many parrallel output devices that this cannot happen even if you short out the speaker terminals, this also extracts a price in size, weight and expense. There are some very expensive amps that are designed to do all of the above, but the capability is wasted on most owners since they will never uses their amplifier under such extreme conditions.

    Since few amps are designed to deliver all the current demended under any conditions, they normally have a protection circuit that limits the voltage/current combinations that asre possible. Typically there is no limitation unless the speaker impedance drops below 2 or 3 ohms. Only a few loudspeakers do this and I can't think of any really good reason why they should since many superb loudspeaker designs exist that do not make such extreme demands. Anyway this protection circuit is a potential source for clipping but this is not a common ocurrance with most loudspeakers.

    Finally, watts= voltage x current. So you can see from this and Ohm's law why watt ratings are stated for a particular load expressed in ohms. You may also them conclude (correctly) that watts is another nominal figure and really is just a general indicator of capability that depends on other circumstances as well.
  • 09-09-2005, 05:17 AM
    Worf101
    You forgot one....
    Quote:

    Originally Posted by twochannelsonly
    I guess alot of us take it for granit and know all the answer's ... LOL

    Noun: clipping kliping
    An excerpt cut from a newspaper or magazine
    "he searched through piles of letters and clippings"
    - newspaper clipping, press clipping, cutting, press cutting

    Cutting down to the desired size or shape
    - trim, trimming

    The act of clipping or snipping
    - clip, snip
    Verb: clip (clipped,clipping) klip
    Sever or remove by pinching or snipping
    - nip, nip off, snip, snip off

    Run at a moderately swift pace
    - trot, jog

    Attach with a clip
    "clip the papers together"

    Cultivate, tend, and cut back the growth of
    - snip, crop, trim, lop, dress, prune, cut back

    Terminate or abbreviate before its intended or proper end or its full extent
    - curtail, cut short


    Derived forms: clippings

    Type of: attach, cut, cutting, cutting off, excerpt, excerption, extract, run, selection, shorten, thin out

    Antonym: unclip

    Encyclopedia: Clip

    Clipping

    And if all that doesnt help click the link below. ;)

    Click here for great clipping read

    To "clip" someone in "The Soprano's" sense of the word, to kill a guy. Push a button on a guy. Send em to sleep with the fishes. etc....

    Da Worfster :D
  • 09-09-2005, 04:32 PM
    twochannelsonly
    Quote:

    To "clip" someone in "The Soprano's" sense of the word, to kill a guy. Push a button on a guy. Send em to sleep with the fishes. etc....
    Darn missed one...LOL

    Thanks Worf101