I found this speaker at a recyclers and Ive replaced the tweeter diaphragm but there are no markings whatsoever on the woofer so I cant find any specs for it. I have no idea what I'm doing with this now, I don't know if its a P.A. speaker or a guitar speaker box or what? Can anyone suggest a crossover for it or how I could use it?
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It LOOKS like a practise guitar speaker to me. The corrugated bass seems to say that.
How big is the bass and does it have a cloth or rubber surround? you usually measure the diameter of the frame in inches.
You'll probably end up with an LC filter and some attenuation on the horn unit. The bass might get a coil or nothing at all.
How big is the bass and does it have a cloth or rubber surround? you usually measure the diameter of the frame in inches.
You'll probably end up with an LC filter and some attenuation on the horn unit. The bass might get a coil or nothing at all.
I really can't claim to know a lot about a 12" bass plus Horn tweeter, but can do a rough sim using another tweeter and a conventional 12" hifi bass.
What makes the combination good, is the time alignment you get by setting the tweeter back in a horn. Here I set the acoustic centre of the tweeter a mere 2 cms in front of the bass' acoustic centre. You can see how big basses rolloff steeply. People like Klipsch use 2nd order filters on both drivers, so I've gone with that. I can't comment on whether the horn needs equalising. A lot do.
This particular speaker is more of a wallmounter than a stand alone. We have no idea of efficiencies here, so I can't really guess the attenuator values beyond being about 8 ohms load overall to the LC. Impedance dips lower than I would like, but not bad.
You wouldn't get away with this circuit with a regular tweeter on a flat baffle. Phase would be horrid.
Whether you want to try this is up to you. It'll take a bit of fiddling to get right.
What makes the combination good, is the time alignment you get by setting the tweeter back in a horn. Here I set the acoustic centre of the tweeter a mere 2 cms in front of the bass' acoustic centre. You can see how big basses rolloff steeply. People like Klipsch use 2nd order filters on both drivers, so I've gone with that. I can't comment on whether the horn needs equalising. A lot do.
This particular speaker is more of a wallmounter than a stand alone. We have no idea of efficiencies here, so I can't really guess the attenuator values beyond being about 8 ohms load overall to the LC. Impedance dips lower than I would like, but not bad.
You wouldn't get away with this circuit with a regular tweeter on a flat baffle. Phase would be horrid.
Whether you want to try this is up to you. It'll take a bit of fiddling to get right.
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Pa drivers require different crossovers, impossible to guess with mystery drivers. Look at the crossovers for PA drivers like Eminence, others. Study the work from Wayne Parham (with SPICE) and give a go to the Econowave. Any xover might work mediocre without the driver parameters, sorry. Regards.
Zilch's AK Design Collaborative - Econowave Speaker - AudioKarma.org Home Audio Stereo Discussion Forums
What is a P.A. Speaker Cross Over? - YouTube
Assembled Passive Crossovers in the Speaker Components Department at Parts Express | 308
http://www.diyaudio.com/forums/mult...esign-12-woofer-12-waveguide.html#post3457872
Zilch's AK Design Collaborative - Econowave Speaker - AudioKarma.org Home Audio Stereo Discussion Forums
What is a P.A. Speaker Cross Over? - YouTube
Assembled Passive Crossovers in the Speaker Components Department at Parts Express | 308
http://www.diyaudio.com/forums/mult...esign-12-woofer-12-waveguide.html#post3457872
An oscilloscope is a good thing but isn't of much help in this aspect of crossover design. Before computers were used in this way, I used to use my CRO to plot impedances and other things, now I save it mostly for making amplifiers.
The primary choice here will be in matching the dispersion of the two drivers. Look at the angle of the tweeter. the woofer will be narrowing to this angle somewhere above 1kHz, possibly 2kHz.
Next, can the tweeter do this frequency well? It looks a little small for this. You'll be compromising by crossing higher but sometimes this is a better option.
The primary choice here will be in matching the dispersion of the two drivers. Look at the angle of the tweeter. the woofer will be narrowing to this angle somewhere above 1kHz, possibly 2kHz.
Next, can the tweeter do this frequency well? It looks a little small for this. You'll be compromising by crossing higher but sometimes this is a better option.
I have absolutely no idea of what a BR box is,I take it that Fs is frequency? If it is, that is basically what I'm asking about here? How do I find the crossover frequency? What do people do if they are in my position when they cant get the specs for a perfectly good driver,throw it in the bin? Maybe someone can recognize what type or model of driver the woofer is and I can go from there?
When people don't know (the reference/model), they will have to measure the driver or take it to someone that can do it.
When, like some member, don't want to go with tech simulations and measurements they go here (link below), but they usually have the manufacturer parameters sheet already.
http://www.diyaudio.com/forums/mult...designing-crossovers-without-measurement.html
ps. to know the freq. of the crossover you need to know the T/S parameters and the roll offs/break-ups for the drivers (usually in a graphic format). then, in the end, adjust the final output of the horn to match that of the woofer.
When, like some member, don't want to go with tech simulations and measurements they go here (link below), but they usually have the manufacturer parameters sheet already.
http://www.diyaudio.com/forums/mult...designing-crossovers-without-measurement.html
ps. to know the freq. of the crossover you need to know the T/S parameters and the roll offs/break-ups for the drivers (usually in a graphic format). then, in the end, adjust the final output of the horn to match that of the woofer.
All the specs can be measured and they'll help you in building a box.
The specs aren't necessary in choosing a crossover frequency. You should be able to cross anywhere below 1kHz, and higher if you're crossing to a horn.
If you have a frequency generator (could be a PC with free software plus a good amp) and an oscilloscope, you have just about anything you need to determine the speaker parameters yourself. That will most likely be better than some looked-up specs, even if you can find them.
Search the web for something like "determining Thiele-Small parameters" or so. I never designed an enclosure or a crossover without measuring the exact TSP's myself. The specs were just a guideline. So do not worry that you don't have the specs.
BR, by the way, refers to Bass Reflex, one of the standard enclosure designs which your enclosure might be from what I can tell by looking at your pics.
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