Mismatching Speaker Power Ratings

[hossymandias]

Okay, I'd like to replace a bad speaker in my Silvertone 1484. I think it went bad because the stock is only two 35 watt speakers, and I tend to use a lot of high gain pedals through it.

I'd like to replace the bad one with a higher wattage, so my amp doesn't blow another speaker.

Can I mismatch speakers with different power ratings? Say, a 35 watt and a 100 watt? Or do I need to match them?

Thanks!

[matt h]

(deleted)

[vibratoking]

Okay, I'd like to replace a bad speaker in my Silvertone 1484. I think it went bad because the stock is only two 35 watt speakers, and I tend to use a lot of high gain pedals through it.

I'd like to replace the bad one with a higher wattage, so my amp doesn't blow another speaker.

Can I mismatch speakers with different power ratings? Say, a 35 watt and a 100 watt? Or do I need to match them?

Thanks!

The speaker could have gone bad for many reasons. Can't tell from you stated above. It's true that the new, higher wattage speaker will be less likely to fail due to power dissipation. BTW, it may sound worse because it is not being driven anywhere near it's sweet spot...YMMV. The situation on the old speaker may or may not be changed. A 35W and and 100W speaker, of the same impedance, will both dissipate the same amount of power. The power handling capability per speaker will not be changed. The 100W speaker will not magically absorb power in order to save the 35W speaker.

To unevenly share power, you need to mismatch the impedances. Then consider the power rating that is necessary to support the impedance and wiring scheme of the speakers. This calculator will show you what you need to accomplish what you want. Make sure you understand the differences between series and parallel wiring. You can make the math work using the link. The result may or may not be sonically pleasing for quite a few reasons.

http://www.speakerimpedance.co.uk/

[RCGPNY1]

Matt H and Vibratoking's responses are right on point. Also keep in mind that speakers fail for 2 genral reasons: thermally and mechanically. Also remember that power handling of distorted waveforms is much less than clean signal.(sometimes up to 50%). Too much bass will make the wrong speaker fail even with modest power input

[pops]

Have a friend using a 10" 150 watt and a 12" 70 watt in his twin. Put the ten in to get a wider range of sound. Sounds great and it has been 15 years now. Mismatch can be great sonically put in what you like the sound of, keep the ohms the same, efficiency would be nice if it was close, but if it sounds good do it. The amp only cares about the load it sees.

[pdf64]

I've got a few 70's greenbacks (well, blackbacks); one of them failed from what (on examination) appeared to be a manufacturing defect (kink in wire running along the former to the voice coil).
The point being that things can just fail, without them being pushed near to, or beyond, their specified limit; they may just happen to be an outlier on the bell curve of power handling capability, the next 99 off the line may have been fine in the same circumstances.

[Stevem]

Those amps with there stock small under rated output transformers are good for a max of 35 watts peak!
The stock output transformers are terriblely small for a amp with duel 6L6 output tubes,in one of my 1484 Amps I replace the OT for a larger one and now the amp outputs a clean 32 watts rms with a peak power of 45.

If it's the stock jensen speaker replace it, get it re coned, but do not toss it as even in its blown condition it's worth 40 bucks!

Are you sure it's blown and not the baffle that is making noise? As these cabinets have baffles made of only 1/4" Masonite and they tend to fall apart around where the speaker mounting studs are especially if the nuts on the studs get over tightened the studs can start to pull through the baffle!
On my first 1484 I made and glued on wood reinforcements fanned out around each speaker just to make the baffle more ridgid for bass notes and it helped, then I came to find out that the speaker openings cut out in the baffle are way smaller than what's needed for a 12" driver!
I then made a new baffle out if 1/2" plywood which worked out great, but due to its added depth the wood locating strips for the head storage must be moved 3/8"s closer to the rear of the cabinet also.
The sound is now way better then the stock baffle with the wood reinforcements that I had on the original baffle and worth every bit of work to do so!