What to us for a PA dummy 300W load?

You will probably get advice to use a string of light bulbs for this purpose, but I have to advise caution there. The resistance of an incandescent bulb is very low when cold, and rises significantly when current is applied. It's not easily predicted and can lead to blowing your amp. The bulbs can easily look like a short to the amp when cold and kill it before you get started with a test. You should look for something that has less resistance change when heated. Thinking of the heating element from a toaster, electric frying pan, electric space heater or other household appliance. Of course, you'll have to measure and combine appliances as appropriate to get the right value.

Of course, the correct solution would be to spring for the resistor(s) to do your testing.

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Buy wire wound resistors

First you have to tell us what "rated" means. Is this 300 watts pure sine wave power or the poorly defined "music power". I doubt that there are speakers available that would take 300 watts CW.

Jim

-- "It is the mark of an educated mind to be able to entertain a thought without accepting it." --Aristotle

something like this :

There are loads of options. Farnell sell ultra-large wirewound resistors for example.

Graham

I know one that takes 1200W ! It has a 6 inch voice coil though !

Graham

I seem to recall reading about using a toaster, or at least the toaster's heating element, as a load for an audio amplifier.

It likely helps to explain why you need the load. Once upon a time, every amplifier needed a load, because the design required it. But most solid state amplifiers can operate without a load, so the need for a load may no longer be needed, depending on what you are doing.

Michael

In message , Eeyore writes

Or plenty of smaller cheaper ones although I do have a couple of their

If you can scrounge up 3600W worth of 120V heating elements from junk equipment and wire it in parallel that'll be 4 ohms.

Otoh you could just some of the nichrome wire from an old toaster

Bye. Jasen

Cerwin-Vega, I'll bet. Their slogan is "The LOUD!speaker company." They build systems for rock concerts, motor-race tracks and other places that need insane amounts of acoustic power.

They

"A favorite demonstration of mine was to plug the ML-4 woofer section into the 120-volt wall outlet. This really captured the attention of visitors who questioned the power handling of the system, and it was also very loud. "

It's possible Cerwin-Vega might have one but the one I had in mind is made by a British Company called Precision Devices who build professional loudspeaker drive units for the sound reinforcement and monitoring market.

The chassis diameter is also 24 inches ! And the cone feels almost more like hardboard than paper, it's that thick. Am impressive beast for sure.

Graham

I've heard that quote before. I bet he didn't do it for long though. With an 8 ohm driver that's 1800W continuous.

Graham

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he goes on to state that actually, the impedance at 60 hz was 30 ohms, so it wasn't a problem. if they were like the ML1s, they were actually designed to tighten up in the bass to eliminate flabby resonances, and Mcintosh supplied an equalizer which ramped up sharply in the way low bottom to compensate, so you could get bass which was both deep and well defined; with the monster Mcintosh amps that was eminently doable. i had a pair of ML1s for a while; still have the equalizer. they were certainly not lacking in bass even when not equalized, and with it they went down further than my record collection ever needed.