What's a bass bin?

A bass bin is kind of like an alternative to a subwoofer. The only ones I have had contact with are the less than stellar Cerwin-Vega 18" folded-horn variety that we use at my work. They're supposed to be long-throw, or something like that, but I just find them boomy and very inefficient. It's bascially jsut a big speaker designed for low frequencies; the bass.

 

I think bin is P.A.-speak for a horn-loaded cabinet, something like this:



or this:



A FX loop is used to put a FX unit between preamp and poweramp.

There is either a preamp out or a FX send that is connected to the input of your FX unit, the outputs of the FX unit are connected to the poweramp in or the FX return.

A serial FX loops puts 100% of the preamp signal through the FX unit. The original preamp signal is lost, you only get the signal that is modified by the effects.

With a parallel FX loop you can blend the clean sound with the effects sound, which can give you more clarity, especially with bass.

 

THAT'S the one... ~shudder~

 

You can, but it's an old design primarily for P.A. use, so it's not the best choice.

I remember that Mike Watt used a Cerwin-Vega in his fIREHOSE days.

I'd still recommend a 4x10 cab.

...and of course you need an amp.

 

Wow man... talk about a flashback! Its so tripy. Before the SVT and acoustic 360 bass rigs wern't very well thought out. Having unfinished wood on stage was far out. I built two of those horns on the bottom of your post from free JBL plans driven by JBL D140F's if my memory hasen't melted. Powered by two Marantz 8B's and a Fender Bassman wired with a preamp out. My first GAS realized.

Thanks JMX

 

Oh My,
the top one looks like the old JBL W80 18! I haven't seen one of those for a while. I used to play through a system that had 4 of those for subs and 4 Turbo TMS4's for midhighs, all powered by HH V-800s. Man that rig could make you barf in a club. Yup, bass reflex bins and folded horns are out of vogue in sound reinforcement these days. Everything's front loaded or manifold. Not that I'm complaining. EAW SB850s are way easier to move are stupidly efficient, and go real low. I truly believe that 4 of those in a club could probably make you implode........

 

I apologize for my ignorance, but what exactly does "Folded Horn" mean. When I hear that term, I'm thinking about a 15" or 18" cone that is in the shape of a V.

 

Those things are ugly ugly ugly, I hate horns, unless it's well designed.

 

Interesting. They are pretty good down to 32 Hz. and have a sensitivity of 99 dB (1w, 1m). They are big, but weigh "only" 181 lbs, accoding to the EAW site (see http://www.eaw.com/products/item.phtml?part_number=999104). That's not too bad, but I think the sensitivity is in a lower territory than a good horn system. But since you pro sound guys have megawatt amps at your disposal, you can live with lower sensitivity.
- Mike

 

It means the working principle of the cabinet is a folded horn, and, just like it says, the woofer works on a horn that's folded several time inside the cab to allow reasonable dimensions. It's supposed to increase the efficiency of the speaker, and to project the sound out into an audience up to 300 feet away.

Most bass speaker are "bass reflex". "Ported" is another word for the same thing. It's a similar system, but with lower efficiency, but easier (cheaper!) to design and build.

 

The big deal with horns is they are MUCH more efficient than directly coupled boxes like reflex, sealed, and bandpass types. They are acoustic transformers that match the low impedance of the air to the high impedance of the speaker cone. This makes them loud as hell without a lot of input power and ideal for sound reinforcement systems.

The shorter the horn length, the higher the cutoff frequency. Folded designs also start to have reflection and cancellation issues with higher frequencies whose wavelengths approach the internal dimensions of the horn, and the response becomes very ragged.

Something else to point out is the -3 dB cutoff point on a horn, folded or straight is a function of the wave length and mouth diameter. A horn has to be 27 feet long to accurately reproduce low E, and a bit longer than 36 feet long for low B. Frequencies below this sharp cutoff point are just the driver itself projecting into the confined space of the horn but without the acoustic coupling.

Horns are directional (beaming) devices in their passbands because they have mouth diameters that are much larger relative to their wavelengths than does a speaker cone. This directional characteristic accounts for the "long throw" or "bloom" terms associated with horns and off-axis sound intensity falls off very rapidly.

 

Thank you for the insight o mighty gods of technical knowledge

 

That should have read: "stupidly efficient for a front loaded box." 1W-1m ratings for horn loaded stuff would be higher. 181 lbs is light for a dual 18 subwoofer. It's certainly lighter and more compact than a Klipsch or a W80 18' or a Butterfly or a Martin.... Not many concert subs go below 32 Hz at any kind of SPL. Those reflex cabinets are lucky if they go below 40Hz. I don't buy the directional control thing either. In order for the reflex stuff to control, say 50 Hz, the horn mouth would need to be about 22x22 feet. I've found that arrays of the old style subs tend to be really deficient below about 80 Hz (or at close range). We're powering our SB850s with QSC MX3000's. One amp channel per driver . An array 4 wide X 2 high can be pretty intense. I stack them because when they're 8 wide, the horizontal pattern is too narrow and the vertical one is too wide. The low end definately sounds tighter and better controlled when they're stacked. Anyway, I have to go back to my programming assignment but I could yak about this stuff all day......

 

Which explains why,at only 125 watts,my old acoustic 136 caused stuff to fall off my mother's shelves.And it was just a cheap imitation of a folded horn(the "horn"was a flat piece of plywood).I had the cops called on me twice in two different neighborhoods in the first week I owned it.

 

Check out this picture...it's the one belonging to John Entwistle...

 

I thought those were just big empty wooden boxes with fancy curved pieces of wood for some sort of sound re-direction or something.

 

They are back loaded horns. The speakers are inside the cabs and one side connects to the horn, the other side is looks at a closed volume.

 

Hmmm. wow. My previous rig incorporated one of these! before I had my polysonics 1x12's, I had 1x12+tweeter combo @160 watts sitting on an old Mitchell (anyone give me info on this?) subwoofer. It's kind of a variation on the old cerwin vega's, I;m told. single 18" facing up into an angled baffle, with a sealed space behind it. work for what I was doing! Much rumble! not good definition though...course, all I had was a DCM 18 and a Peavey CS-200 (also old), so...

does anyone know anything more about this cabinet?