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identify the speakers!
Old 20th March 2019
  #1
Gear Head
 

identify the speakers!

hi,

sorry if this belongs in the "live" section but they don't seem very PA-y to me.

also i apologise for the poor image quality/low light
Attached Thumbnails
identify the speakers!-img_2308.jpg  
Old 20th March 2019
  #2
Lives for gear
 

The aluminum edging looks very similar to an EV bass cab my buddy has. They typically stock JBL speakers in their cabs.
cant be sure who actually made the one you posted but it does appear to have JBL's. The aluminum dust caps were used by Altec, JBL. A few other cheap speaker manufacturers used them like Kustom, Univox, Realistic used dust caps to make them "look like' quality speakers but sounded like crap.

The Altecs that's had them usually had White frames, so I'm pretty sure these are JBL's unless EV had some. EV did made some excellent speakers for awhile there. It would be impossible to know unless you could see the backs of them.

These bins do have horns and small tweeters. I suspect they should pretty good. I cant tell how big the speakers are by the pics. It looks like there's a 15" and a 12" in there. May be a 15" and 10" or 12" and 10" The angle of the photo's can make the top look larger then the bottom when taken on an angle like that.

If they are JBL's it would be good to know what kind of horn driver and crossover they're using. These could very well be home built cabs too. I've built many myself which use aluminum edges to prevent it from getting beat up. This one does seem to be plain wood vs Tortex or carpet which does make me thing they might be hand built. They could also have been covered at some point and had that removes and simply painted black.
Old 20th March 2019
  #3
Lives for gear
 
Murky Waters's Avatar
 

Look homebrew. Pull out a component or two to see the manufacturer(s).
Old 21st March 2019
  #4
Gear Head
 

Quote:
Originally Posted by wrgkmc View Post
The aluminum edging looks very similar to an EV bass cab my buddy has. They typically stock JBL speakers in their cabs.
cant be sure who actually made the one you posted but it does appear to have JBL's. The aluminum dust caps were used by Altec, JBL. A few other cheap speaker manufacturers used them like Kustom, Univox, Realistic used dust caps to make them "look like' quality speakers but sounded like crap.

The Altecs that's had them usually had White frames, so I'm pretty sure these are JBL's unless EV had some. EV did made some excellent speakers for awhile there. It would be impossible to know unless you could see the backs of them.

These bins do have horns and small tweeters. I suspect they should pretty good. I cant tell how big the speakers are by the pics. It looks like there's a 15" and a 12" in there. May be a 15" and 10" or 12" and 10" The angle of the photo's can make the top look larger then the bottom when taken on an angle like that.

If they are JBL's it would be good to know what kind of horn driver and crossover they're using. These could very well be home built cabs too. I've built many myself which use aluminum edges to prevent it from getting beat up. This one does seem to be plain wood vs Tortex or carpet which does make me thing they might be hand built. They could also have been covered at some point and had that removes and simply painted black.
Quote:
Originally Posted by Murky Waters View Post
Look homebrew. Pull out a component or two to see the manufacturer(s).
thanks for both of these! i'll open them up and post what i find. was hoping i wouldn't have to bother if the model was obvious. it's very possible they are home-made as a lot of the other stuff i've come across in the pile is the same (though some have had great drivers inside)
Old 21st March 2019
  #5
Lives for gear
 

So long as its well built and has the proper air volume for the speaker sizes. Cabinets For Bass and PA need to have the correct air volume in order to have the bass resonate properly. Think of it like having the right shock absorbers for a car. If the shocks are too weak, the ride is flabby, too hard, there's no cushioning at all. The air in a sealed cab acts like a shock absorber to the speaker when it moves. If its correct the speaker can get to its maximum bass levels without the speaker cone distorting. The air acts like shock absorber.

In a vented/reflex cab the air again does cushion the cone but the air coming out of the vent needs to be in phase with the speaker which is why many cabs have either tubes or baffles to delay the air coming out through the vent and being sucked back in. It only takes a few milliseconds of delay to put them in phase so the speaker and vented waves aren't cancelling each other out. You typically use the specs of the speakers and an on line calculator to calculate the air volume and cabinet specs. When buying replacement speakers its important you match the same specs, not simply the wattage of the speakers. If you have stereo pairs of cabs and don't match the specs of one that's blown you have completely different bass tones coming from each cab, or have some notes match and others that don't. It winds up throwing your audio image first more left them more right depending on which cab is resonating at what pitch.

Back when I first got my electronics degree I worked for a company that built customized sound systems so you had to know how to properly tune the cabs built. We were so good at it you could get a tuning fork to resonate off the cabinet. Basically you use a meter on the cab then you feed the cab a test tone that matches its resonance. Then you adjust the length of the port till you'd get the maximum volume at that frequency and get the meter to max out. When the air volume is correct the speaker stops bucking against the air and moves freely like a piston. When its tuned you get the maximum cone excursion for its resonant frequency and you get the proper bass response and loudness for the cab.

If you simply throw speakers in a cab because its a convenient size then you'll likely never get the proper tone from the cab. You can of course try and compensate using crossovers to feed drivers fixed frequency levels and use an EQ to taper what the power amp is feeding them but, you'll find you loose all kinds of driver efficiency if the speakers are too far out of specs with the cab. When running vocals with a band you can the bass boom out on some notes that interfere with other instruments, then sound thin as hell on others where the vocals get buried by the rest of the band. I remember some of the early cabs I built. Had no idea of the science behind it and even with good speakers you'd be fighting to hear yourself through them.
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