Let's say I have a 500w bass head, and a pair of 250w 8ohm cabs, and they have been a good match so far as a little stack. Let's also say I am considering going on tour with only one of the cabs to save space. I believe the output of the amp drops to something like 380w at 8ohms, but I'd still be running 380w into a 250w cab which raises a red flag as potential for blowing the driver. Is there anything I can put, say inline, to protect the cab without killing the sound? Or do I just have to 'be careful' or 'know my limit' or something along those lines? Any other suggestions appreciated, thanks.
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Protection for underpowered cab?
- Thread starter foetus66
- Start date
okcrum
in your chest
My stove is underpowered. It just burned a pizza.
380 watts? Most of my 500 watts at 4 ohm amps have dropped to nearer 250 watts at 8 ohms.
What amp and cab are you using? And how loud do you run your amp?
I never run my rig flat out so I'll never damage one cab. If I was in danger of pushing one cab too far I'd take both cabs, because the tone of one smaller cab trying to do it all won't be a great bass sound.
How much space are you trying to save? It's not worth the hassle. Take both cabs.
What amp and cab are you using? And how loud do you run your amp?
I never run my rig flat out so I'll never damage one cab. If I was in danger of pushing one cab too far I'd take both cabs, because the tone of one smaller cab trying to do it all won't be a great bass sound.
How much space are you trying to save? It's not worth the hassle. Take both cabs.
If you have a passive bass going straight into the amp it's not hard at all. Wail on the bass with your usual EQ and turn up until it complains, then turn down. Go to rehearsal and see if you can still hear yourself with the cab up a couple of feet.
If it goes good you're all good, but if it fades out you're probably stuffed unless you can turn down more.
What you're asking about is a limiter to protect your cab. You could do that but it will interfere with your sound.
If it goes good you're all good, but if it fades out you're probably stuffed unless you can turn down more.
What you're asking about is a limiter to protect your cab. You could do that but it will interfere with your sound.
SirMjac28
Patiently Waiting For The Next British Invasion
keep a fire extinguisher near by
If you can hear it onstage, that's all you need. Three-80 into 250 isn't a problem, unless you insist on diming the amp, in which case a 150-watt amp would be just as destructive. But why would a smart person do that?
By strictest definition, you'll be fine provided you use some common sense. That being said, are you able to contend with the discernible loss of volume?
Riis
Riis
Best protection for this is a volume knob. You just don't turn it quite as far to the right as before.
Actually, JimmyM has the correct answer.
Your amp isn't putting out full power unless you crank it up to full power.
Actually, JimmyM has the correct answer.
Your amp isn't putting out full power unless you crank it up to full power.
Only If you play the bass.
Walleyes aren't fishy at all.
Never understood the appeal for salmon. Very fishy fish that one.
What kind of music are you playing? You should be fine, just use common sense and trust your ears.
Which is why I spelled out how to find the limit and test the resulting volume before going to war.
scottfeldstein
Roots and fifths and a little extra.
Unless I'm misinformed the watt rating on speaker cabs is referring to the watts it can supposedly handle before there's a failure in the circuitry. But when we all talk about exceeding a cabs capabilities, we're talking about the first thing that fails--mechanical failure. The cone blows out. That happens WAY before the other kind of failure. Therefore, the watt ratings are not an indication of how much power a cab can take before it fails. Whatever that rating is, it's going to fail a long time before it has that much power poured into it.
That said, just because your amp says "300w @ 8ohms" doesn't mean you're putting 300w into the cab. If the volume isn't all the way up, you're not. (Except for maybe transient spikes? Not positive.)
Soooo... as has been said above a number of times: trust your ears. That's what's going to tell you if your speakers are exceeding their mechanical limit. Not the watt rating on the back of the box. And if your speakers start farting out or showing other signs of distress, turn down the volume. Or turn down the bass frequencies. Or both.
That said, just because your amp says "300w @ 8ohms" doesn't mean you're putting 300w into the cab. If the volume isn't all the way up, you're not. (Except for maybe transient spikes? Not positive.)
Soooo... as has been said above a number of times: trust your ears. That's what's going to tell you if your speakers are exceeding their mechanical limit. Not the watt rating on the back of the box. And if your speakers start farting out or showing other signs of distress, turn down the volume. Or turn down the bass frequencies. Or both.
Turning down the bass, and/or employing a high pass or limiter, transfers the failure mode to thermal when there is power on tap.
I alluded to thermal mode when mentioned the possibility of fading out when testing with the band. That's the coil beginning to burn up.
