Wattage issue on matching cabinets

[ABNJbassplayer]

Hi: Is it true that if you want to match cabinets, they should be close to equal in wattage or else one cab will overpower the other? I have a 450 watt head at 4 ohms, and a 700 watt cabinet at 8 ohms. I want to get the full 450 watts of the amp by adding another 8 ohm speaker, but does it have to be close to the 700 watt cabinet I already have? What's the lowest wattage I can possibly go to on a new purchase to compete with the 700 watt cab?

[jmercer91]

Get the same cab and stack em.

[gnjpowell]

Multiple cabs driven by the same amp should all be identical.

[Holliwood]

What he said.

Get EXACTLY the same cab.
If you don't, all the drivers may not get the same amount of power and it'll sound like crap

[billfitzmaurice]

Originally Posted by ABNJbassplayer

Hi: Is it true that if you want to match cabinets, they should be close to equal in wattage or else one cab will overpower the other?

No, because power ratings don't tell you how much power a cab can actually use. Only displacement tells you that. But as only one company in the world, Barefaced Bass, gives displacement ratings you simply have no way to compare different cabs. This is but one more reason why you don't want to mix cabs, keep them the same.

. I want to get the full 450 watts of the amp by adding another 8 ohm speaker,

That's also a moot point. More watts don't necessarily equal more output.

[will33]

Speakers don't overpower anything. They don't send power, they recieve it. If both cabs are of the same impedance, each will recieve 1/2 the power the amp is sending. One of the drawbacks to the 15+410 stack you see all the time. The 15(one speaker) gets 1/2 the power and has to take it all by itself. The 410(four speakers) gets the other half with 4x the speakers to take it. The 15 hits it's limit while the 410 could still be getting louder.

[JHAz]

Originally Posted by ABNJbassplayer

Hi: Is it true that if you want to match cabinets, they should be close to equal in wattage or else one cab will overpower the other? I have a 450 watt head at 4 ohms, and a 700 watt cabinet at 8 ohms. I want to get the full 450 watts of the amp by adding another 8 ohm speaker, but does it have to be close to the 700 watt cabinet I already have? What's the lowest wattage I can possibly go to on a new purchase to compete with the 700 watt cab?

_1 to Bill F and Will.

Do you need to be louder? If not, you will not actually use more power anyway. Your amp does not put out a constant wattage. When you turn down, it puts out less and your speakers get quieter, when you turn up it puts out more and your speakers get louder, up to a point. If you add identical speakers and keep the power the same (which would require you to turn down a notch) you'll be a bit louder because of doubling the number of speakers. To stay the same loudness, you'd actually use less power with more speakers, theoretically, all other things being equal, etc.

Of course, nothing says it's necessary (or even a good idea) to drive your amp toits limits all the time, anyway . . .

[BurningSkies]

Originally Posted by will33

Speakers don't overpower anything. They don't send power, they recieve it. If both cabs are of the same impedance, each will recieve 1/2 the power the amp is sending. One of the drawbacks to the 15+410 stack you see all the time. The 15(one speaker) gets 1/2 the power and has to take it all by itself. The 410(four speakers) gets the other half with 4x the speakers to take it. The 15 hits it's limit while the 410 could still be getting louder.

MY SPEAKAS WILL OVAPOWA YOU!!!!!

[Joe Louvar]

Originally Posted by ABNJbassplayer

Hi: Is it true that if you want to match cabinets, they should be close to equal in wattage or else one cab will overpower the other? I have a 450 watt head at 4 ohms, and a 700 watt cabinet at 8 ohms. I want to get the full 450 watts of the amp by adding another 8 ohm speaker, but does it have to be close to the 700 watt cabinet I already have? What's the lowest wattage I can possibly go to on a new purchase to compete with the 700 watt cab?

This is what Eminence say’s about it ~

Power handling
This specification is very important to transducer selection. Obviously, you need to choose a loudspeaker that is capable of handling the input power you are going to provide. <snip> The ideal situation is to choose a loudspeaker that has the capability of handling more power than you can provide lending some headroom and insurance against thermal failure. <snip>

Generally speaking, the number one contributor to a transducer’s power rating is its ability to release thermal energy. This is affected by several design choices, but most notably voice coil size, magnet size, venting, and the adhesives used in voice coil construction. Larger coil and magnet sizes provide more area for heat to dissipate, while venting allows thermal energy to escape and cooler air to enter the motor structure. Equally important is the ability of the voice coil to handle thermal energy. Eminence is renowned for its use of proprietary adhesives and components that maximize the voice coil’s ability to handle extreme temperatures. Mechanical factors must also be considered when determining power handling. A transducer might be able to handle 1,000W from a thermal perspective, but would fail long before that level was reached from a mechanical issue such as the coil hitting the back plate, the coil coming out of the gap, the cone buckling from too much outward movement, or the spider bottoming on the top plate. The most common cause of such a failure would be asking the speaker to produce more low frequencies than it could mechanically produce at the rated power. Be sure to consider the suggested usable frequency range and the Xlim parameter in conjunction with the power rating to avoid such failures. <snip> Understanding Loudspeaker Data | Eminence Speaker

[cchorney]

Originally Posted by will33

Speakers don't overpower anything. They don't send power, they recieve it. If both cabs are of the same impedance, each will recieve 1/2 the power the amp is sending. One of the drawbacks to the 15+410 stack you see all the time. The 15(one speaker) gets 1/2 the power and has to take it all by itself. The 410(four speakers) gets the other half with 4x the speakers to take it. The 15 hits it's limit while the 410 could still be getting louder.

+1

This must be my day for agreeing with everything I see Will33 post. I gotta get my posts in ahead of him so I can get him agreeing with me instead!

[will33]

Originally Posted by cchorney

+1

This must be my day for agreeing with everything I see Will33 post. I gotta get my posts in ahead of him so I can get him agreeing with me instead!

I'll take a break for a while, let you catch up.

[Joe Louvar]

Yeah, just don’t turn up the volume too high!!!