My favorite little speakers can’t handle any volume anymore because they go all buzzy. Is that the woofer?
And what is a SUB-woofer?
Could be either. Any deformation or damage to either the woofer or tweeter could result in distortion.
A sub-woofer is just that: a woofer that handles lower frequencies, the kind you [del]hear[/del] feel when some punk pulls up beside you at the lights.
If the speakers are “little” like you say, they may not have woofers at all.
Subwoofer: The typical frequency range is about 20–200 Hz for consumer products.
200 is awfully high for a subwoofer’s high-pass. “Real” subs are substantial pieces of furniture - I’ve got a 12" sub running with a 60 Hz crossover and it could be used as an end table.
As for the buzzing, it depends on the particular speaker - if they’re small, there’s probably only a single wide-range driver. Two likely causes of the buzzing are either the voice coil has overheated and warped and is rubbing on the magnet structure, or the cone’s surround is damaged. Either of these are pretty much fatal.
Are you sure it is the speakers? Could it be the amp? Clipping could cause buzzing, too.
My speakers have the same problem: they buzz at high volumes, and I think the max volume isn’t as loud as it was before. The cones on the tweeters visibly vibrate a lot when buzzing. Can they be saved? They’re really old, about 9 years old.
I like my speakers and they’re considerably older, so I’ve had them re-coned in the past.
I had to detach the speaker from the cabinet and send it back to the manufacturer. Only took them a couple of weeks to send it back each time.
As above, going buzzy is likely the voice coil rubbing in the gap in the magnet. This is often the result of overheating the voice coil though too much power, or by physically damaging the voice coil by driving it into the pole piece (also a result of too much power.) The latter is only a failure mode of woofers, but all speakers can be killed by overheating them.
For good quality drivers, it is often possible to obtain recone kits, or have them reconed. Cost is about half the cost of a new driver.
Sub woofers are a funny thing. The name came about to cover a speaker than covers the deep bass, i.e. frequencies beneath - or sub that - of the woofer. In popular use it seems to have become the name given to any bass driver - which is basically wrong.
A sub woofer driver tends to be different to a woofer in a number of ways. A simple woofer is designed to reproduce not just the bass, but also to reproduce all the frequencies up to where the next smaller driver takes over. For a two way speaker this might be about 2kHz. The need to reproduce such high frequencies places some important constraints on the speaker design, especially the cone. As you reproduce lower and lower frequencies you need to shift a lot more air to reproduce the same sound level. To do this you need either lots of area, or lots of cone travel, or both. A speaker driver designed to operate as a sub-woofer tends to be designed so that it has lots of cone travel (Xmax) and has physical parameters that lend themselves to reproducing low frequencies in boxes that are of acceptable size. These parameters (often called the Theile Small parameters) include such things as the effective mass of the cone, the characteristics of the magnetic motor, and the springyness of the cone suspension. A speaker that is good for low frequencies will often have poor capabilities at higher frequencies - even compared to a conventional woofer of the same diameter. Cone breakup modes - where the cone starts to resonate like a drum skin are a big problem. So it is common to only feed sub-woofers with the very low frequencies. Say up to 80 Hz. (Note, even this is a wide range, the low E on a guitar is 82Hz, and the low E of a bass guitar (or double bass) is 41 Hz. The 5 string variants go down to 30Hz. A 33 inch tympani is almost as low there too.)
In general a sub-woofer is a separate component to the main speaker boxes, this being a way of taking advantage of the fact that bass notes are essentially non-directional. There are however good reasons for using more than one sub-woofer - to attempt to ameliorate problems with standing waves in the room by placing the speakers in different places.
As others have said, your little speaker cabinets probably posses a full range single cone driver (the actual speaker part of the speaker) and it is most likely damaged in a way that is not noticeable at low volumes.
In other speaker systems I’ve worked with the buzzing or clipping at high volumes was usually from cone damage in a woofer.
Tweeter damage in my speakers was typically catastrophic and resulted in no sound coming from the tweeter. I never had a tweeter buzz before dying. Not to say it couldn’t do it but from my experience it hasn’t.
Bubba
Guy who ran a lot of PA sound systems and broke more than a few speaker driver components.
You can visually check the edge of the speaker and the cone to see if either have deteriorated. If they are intact then it’s most likely the voice coil has welded itself from heat generated by high volume.
The amplifier can be tested by hooking up another set of speakers to it and the reverse is also true of the speakers.