What aspects or features of a speaker controls the speakers’ ability to handle heavy base at high volume? Is it wattage?
I need to replace one of my stereo speakers (cheaply!) and while my personal use doesn’t require great volume, my immediate need is to use my speakers for a block party as I have in years past, and the volume needs to be loud without distortion. But I don’t know what to look for in the speaker to know whether it can handle it, aside from knowing that no cheap tiny speaker can do it.
yes, it has to be able to handle the amount of power you want to throw at it.
it has to be able to handle that rated power w/o sounding “distressed” (distorting)
the speaker and enclosure have to be designed together properly.
typically in those kinds of situations people use P.A. type cabinets. Usually they combine a 10"-15" woofer with a horn midrange/tweeter in a ported enclosure. Problem is that those kinds of cabinets are fairly single-purpose; their sound quality is not that great, relatively speaking. They are more designed to produce loud sounds for extended periods of time.
You could probably get by with the old-style floor-standing home stereo speakers; the three-way ones with a 12-15" woofer, a midrange, and tweeter, but beware that they’re not likely to survive being played at high volumes for long periods of time.
Yes, wattage is an important consideration. But, you really want to look at SPL (Sound Pressure Level) vs THD (Total Harmonic Distortion). You want to find a speaker that has the highest SPL while still maintaining low distortion. Be careful - cheap speakers often fudge their power handling. You might consider a PA system rather than speakers designed for the home - most “stereo” speakers are designed for low distortion, and sacrifice volume to achieve it. PAs are designed to output lots of volume, while still maintaining a reasonably clean sound.
If your speakers have worked well in the past, why not buy a replacement of the same model? What kind of speakers do you have? If the same model is no longer made, there is likely a replacement model with similar characteristics.
How often do you need to rock the block? It may make more sense to buy whatever smallish speakers sound good to you for daily use, and for party time, rent a PA rig. I’m sure there’s a few AV rental outfits to pick from in LA.
I would vote for renting too. PA speakers are specifically designed for purpose, and have very different goals and design than domestic speakers.
Power ratings for domestic speakers, are for the most part, essentially fiction. They are made up, and have little to no relationship to how they may be safely used. Speakers are killed in one of two ways - overheating the voice coils, or by mechanically damaging the voice coil by driving them past their mechanical limits. For bass, it is the latter limit. This depends upon the design of the bass driver, the cabinet design, and the frequency it is driven with.
The create loud bass, you need to shift air, a lot of air, and the fundamental determinant on the loudness of the bass driver is simply the volume of air it can sweep, which is area times its excursion. How much power it takes to achieve this is a function of the design of the driver and the cabinet design. Low distortion depends upon a range of things, but mostly design of the driver, especially the magnetics. Low distortion never comes cheap, and comes pretty much as: loud, low distortion, low price - pick two, and often only one.
You can calculate the maximum loudness a speaker is capable of at any given frequency, but it is not usually provided by the manufacturers of domestic speakers. For bass it is limited by the bass driver not being mechanically destroyed, for higher frequencies it is a matter of not overheating the driver. For music signals the heat load is usually less an issue as music is not a continuous signal, however for party and other PA applications this is not nearly as safe to do as for domestic applications. PA systems are designed for continuous high power use.
ETA: The standard question also needs asking: budget? You say “cheaply”. That could mean almost anything.