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Hitting peak does it damage the speaker

Discussion in 'Amps and Cabs [BG]' started by MAJOR METAL, Apr 22, 2004.


  1. MAJOR METAL

    MAJOR METAL HARVESTER OF SORROW Staff Member Supporting Member

    If your playing for extended periods of time hitting peak on your rig is that damaging your speakers?. Thanks
     
  2. JMX

    JMX Vorsprung durch Technik

    Sep 4, 2000
    Cologne, Germany
    Do you hit peak in the preamp or poweramp?
     
  3. MAJOR METAL

    MAJOR METAL HARVESTER OF SORROW Staff Member Supporting Member

    Power Amp
     
  4. BFunk

    BFunk Supporting Member

    Some power amps have built-in limiters. Very short, occasional spikes do not USUALLY hurt the speaker.
     
  5. Is it a peak or a clip? Most modern power amps have a defeatable clip limiter that will kick in when the amp goes in to clipping. In this case the "peak" is handled by the limiter and no damage to the speaker should happen. However, if the amp is going into clipping, this clipped signal can have destortion harmonics that cause accessive power to be sent to the tweaters and crossover components of a 2 way or 3 way speaker system. This can either trip the protection in the speaker or blow the component. Usually you can hear this type of signal as it is not a pleasant thing so if you are hearing a loud farting sound when the peak light comes on then chances are the amp is going into hard clipping. The other thing to remember is that a 350 watt amp can produce 700 watts of clipped signal. If you cab is rated at say 400 watts and your amp is hard clipping a lot, you might blow the whole thing. The real secret is to listen. If everything sounds OK then it probably is.
     
  6. MAJOR METAL

    MAJOR METAL HARVESTER OF SORROW Staff Member Supporting Member

    I am using an Ampeg combo that i can mic i just wouldent want to blow the thing up when i am peaking, i just need to turn down on the gain.
     
  7. Bob Lee (QSC)

    Bob Lee (QSC) In case you missed it, I work for QSC Audio! Gold Supporting Member Commercial User

    Jul 3, 2001
    Costa Mesa, Calif.
    Technical Communications Developer, QSC Audio
    Brief, occasional clips are no problem.

    Sustained, frequent clips are a problem.
     
  8. ..."if you are hearing a loud farting sound when the peak light comes on then chances are..."
    A: You are "hard clipping"
    b: You need to make sure it's coming from the amp
    c: If not, then change what you are eating!
    :D
     
  9. nonsqtr

    nonsqtr The emperor has no clothes!

    Aug 29, 2003
    Burbank CA USA
    Hi Major Metal, I'd say the answer to your question depends on the speakers. Let's say you had gazillion-watt speakers, and you played with the clip lights on all the time. Under those conditions, amp damage would be more likely than speaker damage. Depending on how well the amp is designed (how the power supply is built, and whether or not there's a limiter at work), the amp might be perfectly happy when it's overdriven. Most aren't though, in the owner's manuals they tell you to make sure that the clip light is only on "for a little while at a time", and some of them even give you a number, like 4 seconds or something, which if you exceed the amp will melt down and the world will come to an end.

    Now consider the opposite scenario, which is a huge powerful amp driving an ordinary cab. Under those conditions, you don't even have to be clipping to hurt your speaker. One good thump on the low B might be good enough to send the cone flying across the stage.

    With matched components (let's say your amp and speaker are rated the same), the problem with extended clipping is probably mainly one of heat. If you're operating right on the hairy edge, most of that periodic excess energy during periods of clipping is going into heat (either in the speakers or in the amp). "Eventually", your voice coil may fry, or your amp may go into thermal shutdown. How long that takes probably depends on the quality of the components. You could probably do that all day long with an EVX speaker, I'm not even sure you could blow one of those by overheating it, it has these massive heat sink fins that radiate out from the magnet to help dissipate the excess energy (if you fry one of those, it's probably going to be from too much excursion, like trying to pump too much clean power into it).
     
  10. MAJOR METAL

    MAJOR METAL HARVESTER OF SORROW Staff Member Supporting Member

    Thanks for all your great advice guys, i really am more knowledgeable in the Bass section as opposed too Amplification. :)
     
  11. cb56

    cb56

    Jul 2, 2000
    Central Illinois
    Most Ampegs have limiters on the power section that protect your speakers. as long as you leave it on that is.
     
  12. MAJOR METAL

    MAJOR METAL HARVESTER OF SORROW Staff Member Supporting Member


    Great, they really build these things to last.
     
  13. Im running an Ampeg B2 (rack mounted) and a GK410 cab. My bass hass active pickups, and when I play with the band both my peak (pre) and limit (power) lights blink on and off quite frequently even before Im turned up to band volume level. (Never really noticed it til I read this thread). Im hoping that by adding another 410 cab it will quit clipping so early. If not, I guess I just need more power, huh? So far there's no distortion or meltdown symptoms....thanks guys, now Im gonna worry over my gear all the time! Hahaha!
     
  14. Bob Lee (QSC)

    Bob Lee (QSC) In case you missed it, I work for QSC Audio! Gold Supporting Member Commercial User

    Jul 3, 2001
    Costa Mesa, Calif.
    Technical Communications Developer, QSC Audio
    If you leave your gain and volume settings as is, it'll actually be easier to clip the amp with the second cabinet attached. That's because the additional current required to drive the cabinet will cause the power supply rail voltages to sag somewhat.

    But if you connect the second cabinet and use its additional volume to turn the amp down a little, you'll be less likely to clip the amp.
     
  15. Jerrold Tiers

    Jerrold Tiers

    Nov 14, 2003
    St Louis
    It's fine for the preamp peak light to blink. If it stays on, that might get extra preamp clipping, and you might try the -15 jack.
    If the light never comes on, you need to turn up the bass's volume knob or use the 0db input. Otherwise you will have too little input signal and maybe extra noise.


    The power amp limit light may blink differently depending on style. If you string pop a lot, you probably will see it. If you play straight "walking bass", it might be pretty loud before you see it.

    Same thing, its OK, won't hurt anything in the amp, but the more its on, the more limited/compressed your sound will be. It means you got to full output voltage at least for an instant, and when its on, the limiter is working at least a little.

    If the GK 410 is 8 ohms, yeah, a 4 ohm load will get louder, so another 8 ohm speaker, or a single 4 ohm would help..

    If that isn't enough, then yeah, you might need a bigger amp, or more efficient speaker, or both.
     
  16. MAJOR METAL

    MAJOR METAL HARVESTER OF SORROW Staff Member Supporting Member


    Do you know if the Ampeg B 100 R has a preamp?.
     
  17. Thanks Ampeg Insider! I think the B2 is a really great head, bang for buck! I added the second cab yesterday, an identical GK410 (8 ohm) and played a gig last night with it and it was great! Sounds just the way I want it now. Way more volume than I needed thats for sure. The lights still flicker pretty quick when I play, but the sound stays crystal clear and I think youre right, probably just my hard hitting playing style...(at the 0 Db setting). At -15 I can turn it all the way up and not even reach band volume, and no lights blink at all. Illl keep my ear to it, but hopefully, Im all dialed in.
    Thanks!