Is there any product on the market (or is it even possible?), that is an inline ohm resistor between the amp and the cab that could change a 4 ohm load into an 8ohm load? So, If I have a really powerful amp that puts out 600w at 4 ohms and a 4 ohm cab that can only handle 500w, is there some kind of device/switch that would increase the load and lower the watts reaching the cab?
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Inline cable ohm resistor
- Thread starter lawjazz1
- Start date
Nope.
Just don't turn up loud enough to hurt the cab.
Just don't turn up loud enough to hurt the cab.
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BurningSkies
CRAZY BALDHEAD
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Eminence D-fend
Or a limiter
Or as already mentioned, just don't turn up so much.
Amp makers stretch the truth on how much the amps deliver, and cab makers stretch the truth on how much power they handle.
Or a limiter
Or as already mentioned, just don't turn up so much.
Amp makers stretch the truth on how much the amps deliver, and cab makers stretch the truth on how much power they handle.
Yes. Look on the front of your amp. It's labeled 'Volume'.
BTW, most speakers will start distorting around half their rated power. When that happens turn the volume down, or back off on the bass EQ, or both.
You could construct such a thing but it isn't practical. Would basically be a brick with cooling fins or fan, not just a resistor in the cable.
As said, just be responsible with the volume knob.
They don't make such a thing because it isn't practical.
As said, just be responsible with the volume knob.
They don't make such a thing because it isn't practical.
Reads like you are afraid a 600Watt amp don't fit's to a 500Watt cab.
Don't worry about that slight deviation on paper, that fit's fine.
No one makes a high-powered thing for that (attenuator). You could use an in-line fuse to protect the cab (solid-state amp only). Calculate the correct value based on power and cab impedance. Then when it pops in the middle of a gig too many times you will ignore the calculation and replace it with one of higher value.
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The volume knobs on both your bass and amp are called "pots", or potentiometers. All that means is "variable resistor".
Just use those and your cab will be fine.
Just use those and your cab will be fine.
Ok. I get don't turn it up...duh.....but from reading on Talkbass, there seems to be the opinion that a 600w amp at low volume is still a 600w amp....it is not a 300w amp at 1/2 volume or a 150w amp at 1/4 volume... it could still peak and send a 600w signal to the 500w cab and possibly damage it. Am I right?
600w at 4 ohms.. It's really a Sunn 1200s that puts out 1200w at 2 ohms... So it's not so little. And I'm really just guessing on wattage because the 8 ohm Sunn 410H cab that its paired with is a 300w cab.
My purpose in asking all of this is that my main rig is a Carvin BX1500 with 2 Acme Low b210 4 ohm cabs and I'm evaluating whether the Sunn 1200s can be a back up using the low b2 cabs if the Carvin goes down at a gig.
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That's in the meaning of AES consideration. Clearly it does not meet any mechanical limitations of the cab.
By the other hand a 400 Watt amp would not modify fundamentals here.
I'm sure if the OP had an 400 Watt amp he probably would not ask a question anyway.
AES considerations (like others as well) mainly refere to thermal considerations. That is due to the lack of proper information on mechanical limits. Mechnical limitations depend on driver Xmax AND tuning of the cab but, I never could read anywhere (and no basscab manufacturer will ever provide them) rated specs like 70Watt max at 45Hz or something else.
Again the AES consideration predicates that a loudspeaker can withstand (thermal and mechanical) a rated power of (may be) 500 Watt. That means the 500 Watt AES loudspeaker was tested with a pink noise signal that was limited to +6dB crest (peak to rms ratio). To amplify a signal like that needs a power amp with 1000 Watt capability at least (or greater).
+6dB crest isn't as large as it looks a like. I claim the average bass guitar signal shows crest numbers bigger +10dB at least. Doing the power calculation based on a 600 Watt amp I claim it's hard to get more then 200 Watt power "average" out of this 600 Watt amp.
Right a mechanical limitation is very different but, that wasn't the question the OP asked for!
TL;DR
It is more of a "That's what she said" kind of response to "It will fit".
Law, this is a common misunderstanding. Just because an amp is rated at 500W, does not mean it's putting out that much power all the time. The 500W is the maximum the amp can produce. It only makes that much when the amp's volume knob is up all the way AND the amp is receiving a maximum strength input signal. (The guitar's volume is maxed). Even then, if the bass is passive, the input signal may not drive the amp to its maximum.
So, that amp is only going to overdrive the cabinet under certain conditions. Clearly, many other factors apply. Digging in hard may deliver a stronger signal. Diming the bass can stress the cab badly. This does not mean you have a green light to push the cab as hard as you can. Listen. Your ears are your best friend here.
Raf
Not quite true...
The part about it not delivering 500W when it's turned down is true.
But amps produce their full rated power _at their rated distortion_.
The Volume knob doesn't stop at rated THD, tho. You can usually turn up a lot past rated power. This is one reason why knob position tells you nothing about actual delivered power...
What you hear may or not sound good.
BurningSkies
CRAZY BALDHEAD
- Feb 20, 2005
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Misunderstanding: 500w is what this amp is 'rated' by whatever methodology the marketing team is using. It may produce way more than 500w. It is not a 'ceiling' figure.
Mr. Foxen
Commercial User
Cabs can break when fed less power than their watt rating too. Makes watt ratings pretty meaningless either way. Stuff heading towards breaking sounds bad, so concentrate on sounding good and you are good to go.
