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So, is this bad for my cabinet?

Discussion in 'Amps and Cabs [BG]' started by Sonorous, Jun 20, 2005.


  1. Sonorous

    Sonorous

    Oct 1, 2003
    Denton, TX
    I've got a 4x10 Delta Avatar, which is rated for 1400 watts. I decided to see how loud I could get yesterday, so I turned my 450 watt head all the way up. (Before you tell me that my 450 watt head is only putting 180 watts into the cab because it's 8 ohm... no, the cab is 2 ohms. The head is rated for it as well.)

    My EQ settings are usually a slightly boosted treble, a moderatley boosted high mids, and a bass boosted about the same as the high mids.

    So, instead of turning the master and the gain all the way up at once... I decided to do it in increments for safety. I started by turning the gain all the way up and the master about half way. I hit an open E and could literally see my speakers jump in response. After watching them vibrate (basically looked like a blur of some sort) for a moment I started to get feedback and muted the bass. I tried it again with a few different notes and got the same results.

    This amount of power kind of worried me... so I stopped and turned down.

    It was too loud to really tell if it was distorting or not. I also have no idea what kind of hell this was putting my tweeter through.

    So I mean, 450 watts into a 1400 rated cab... is there really anything to worry about or am I just being a wuss?
     
  2. Funkengrooven

    Funkengrooven Turn it down? You gotta be nuts!!

    Curiosity killed the cat....in your case ...money will bring it back...

    Experiment like that the same way you would gamble in Vegas....

    Risk only what you can afford to lose...otherwise, ..... :bawl:
     
  3. gilbert46

    gilbert46

    Sep 21, 2004
    Sacramento, CA
    Im going to assume you did this in a room?

    In a band setting its amazing how "painfully loud" is acceptable.

    Also, imagine being in a very large room, its going to suck the power right up. fill that room with people and other instruments, and it'll suck up even more power.

    You can here distortion at high volumes just as well if not better I think cause you loose the low end. When my amp clips it kinda sounds like a crappy phaser or something. couldnt explain it but you know when its happeneing.

    Tweeters have a fuse that blows before the horn does in most cases. I think avatar uses them as well.

    Like everything else, you will get over your new purchase protection feelings and thrash on it sooner or later.

    I bought a motorcycle, didnt spin it out for 6 months because I didnt wanna hurt it, but thats what its made to do. This is the same think :)
     
  4. silky smoove

    silky smoove Supporting Member

    May 19, 2004
    Seattle, WA
    Since when is Dave offering the Delta 4x10 in a 2 ohm configuration?
     
  5. Time Divider

    Time Divider Guest

    Apr 7, 2005
    That was my first question as well.
     
  6. Sonorous

    Sonorous

    Oct 1, 2003
    Denton, TX
    Ah, yeah... good point. It was in a average sized garage. I also guess it wasn't distorting then, because it had plenty of low end. :D

    Would the fuse for the tweeter be visible? Like, would it be in the middle of the wire that leads to the tweeter? Or is it hidden somewhere inside the tweeter? I ask because I certainly haven't seen one. Maybe I'll add one if there isn't.

    He isn't. This was a mod done by a professional. (IE: My dad and I.) The reason I didn't ask my dad about this hurting the cab is because he mainly builds tube guitar amps in the 18 watt to 100 watt range. 450 solid state watts is kind of foreign to him, so I figured someone on here would know more.
     
  7. Passinwind

    Passinwind I Know Nothing Supporting Member

    Sounds like you were clipping the preamp section. What happened when you turned gain to halfway and the master full up?
     
  8. Sonorous

    Sonorous

    Oct 1, 2003
    Denton, TX
    I didn't try that.

    Really, the whole thing was just a few seconds of curiosity. Then my curiosity passed and I went back to playing normally.
     
  9. buffordbass

    buffordbass

    Nov 11, 2004
    Dallas
    Endorsing Artist: Genz Benz Amps, Lakland Basses
    The problem with underpowering the cabinet is that once the amp reaches it's maximum / optimal output, anything beyond is just sending distorted signal to the speakers. Asking the amp to put out more than it has is unreasonable. Once it starts distorting, you are overdriving your amp and risking destroying your speakers.

    If you were sending clear signal to them, they could take 1400 watts rms... when sending distortion @ 450 watts, you may get to replace 4x10's.

    Hope that helps.
     
  10. The Avatars don't have a fuse or any other tweeter protection besides the 4.7 uf capacitor.That capacitor is the whole high pass crossover so if it goes the high end goes too.You'd have to get pretty loud or hit a really hard slap or pop to get them to go out though.
     
  11. Sonorous

    Sonorous

    Oct 1, 2003
    Denton, TX
    Well, I don't think it was distoring. Also, the head has a limiter button to press, I think it was on but I'm not positive. I usually just leave it on.

    So you're saying that the capacitor would blow before the tweeter does? If thats not what you're saying... could I add a fuse to the circuit to help protect the tweeter? Also, I bought the cab used a while back ago. The guy said the crossover had been modded to help the tweeter sound less harsh, though when I opened up there was only one capacitor. This is the only cabinet I've owned so I don't have anything to compare to.
     
  12. billfitzmaurice

    billfitzmaurice Commercial User

    Sep 15, 2004
    New Hampshire
    Owner, Bill Fitzmaurice Loudspeaker Design
    You can pop that tweeter with only 10 watts or so if it's 10 watts of pure square wave, and when you push an amp to clipping that's exactly what you're going to get. You can easily pop the tens at half their rated power as well if they're getting square wave signal.
     
  13. lowphatbass

    lowphatbass ****

    Feb 25, 2005
    west coast
    To power a big cab your amp has to do some "heavy lifting" so to speak. By bringing up the Gain you are giving your amp more wattage to do the job. Imaging picking up a heavy box, you don't just want to reach down and grab-it straight legged with one arm, you want to bend at the knees and use all your muscles to spread the load around. This is sort of the same idea with your power amp, the more headroom behind your volume the easier it is for both your amp and cabinet. Unless I am running a really big amp into a really small cab I usually run my gain up 70%-90%, my volume is usually between 2 and 4(out of 10).
    You mentioned that your dad is into tube guitar amps. Guitar players intensionally overdrive their power amps to achieve a desired sound, it's a good thing. For us bass players it's usually not a good thing.
     
  14. Sonorous

    Sonorous

    Oct 1, 2003
    Denton, TX
    Ok, so everyone is getting concerned about the distortion... I don't think it was distorting. It was, however, giving feedback. Thats what I want to know more about. I also wanted to know if I can actually see the speakers vibrating quite a bit, do I have the lows in my EQ turned up too much?
     
  15. BurningSkies

    BurningSkies CRAZY BALDHEAD

    Feb 20, 2005
    Seweracuse, NY
    The distortion may not necessarily sound like the type of distortion you're used to...like guitar distortion. Yes, feedback can also hurt your speaker, as can excessive lows.
     
  16. Plain Old Me

    Plain Old Me

    Dec 14, 2004
    How close to the cab were you standing when you got the feedback? And what head are we dealing with?
     
  17. popinfresh

    popinfresh

    Dec 23, 2004
    Melbourne, Aus
    Hey chris, I'm pretty sure this guy re-wired it from 8ohms to 2. Though correct me if i'm wrong..
     
  18. Sonorous

    Sonorous

    Oct 1, 2003
    Denton, TX
    About 4 or so feet away. Though I wasn't in front and facing it... I was to the side and behind. Mine line of sight was pretty much parallel to what you would have seen if you were standing right in front and looking ahead.

    It's a Peavey 450 MAX. (Or MAX 450?)
    No, you're right.