I'm currently building a pair of very big 3-way speakers with the goal of good sound and high SPL. (If the sound is superb that's a plus, but I'm only going for good.) Oh, and cost. The cost is a huge factor; all the drivers, horns, and crossovers (I've already bought them) cost me less than $200.
The problem I'm having is that while the woofer and horn tweeter are efficient to about 93 dB, the mid-horn (hehe) is efficient to 110 db. (!!!!!)
The mid-horn itself is 6.1 ohms DC resistance, and by my calculations, I need something like 5.97 ohms in series with that, in order to reduce the output to the level of the other drivers. Question 1: did I do that calculation right?
Next question: how's the best way to attenuate this? Ideally I'd build my own active crossover and then triamp the thing (*droool*) but alas, I have not got the money to do such a thing... I'm thinking that if I go to my local art store and buy some BIG pieces of graphite, I can use them as series resistors next to the driver to cool off the sound some.... I mean really, it sounds terrible with the midrange so loud and the treble so wimpy....
Last question: anyone interested if I dig up a digital camera and take some pictures?
The problem I'm having is that while the woofer and horn tweeter are efficient to about 93 dB, the mid-horn (hehe) is efficient to 110 db. (!!!!!)
The mid-horn itself is 6.1 ohms DC resistance, and by my calculations, I need something like 5.97 ohms in series with that, in order to reduce the output to the level of the other drivers. Question 1: did I do that calculation right?
Next question: how's the best way to attenuate this? Ideally I'd build my own active crossover and then triamp the thing (*droool*) but alas, I have not got the money to do such a thing... I'm thinking that if I go to my local art store and buy some BIG pieces of graphite, I can use them as series resistors next to the driver to cool off the sound some.... I mean really, it sounds terrible with the midrange so loud and the treble so wimpy....
Last question: anyone interested if I dig up a digital camera and take some pictures?
Normally you use an L-PAD. One resistor in serie and one in parallel. 10W resistor a normally enough. From my experience, it is hard to calculate the good value because of many factors. Simply buy a variable L-PAD and adjust to taste. When the sound is fine, read the resistor value on the LPAD and then build a fixed LPAD with standard resistor.
Thanks...
I actually discovered that if I take a piece of foam left over from the project, and shape it to fit the throat of the horn, and then jam it in there, it gives about the attenuation I want.
I'm afraid I have neither the money nor the time to spend getting L-pads, and I suspect they wouldn't give the range I wanted anyway; it doesn't matter though, my problem is basically solved.
I spent less than $130 on all the drivers for these boxes, and when you wrap it up to high SPLs, it really shows, especially to people who are spoiled like me. The higs and mids sound like someone is going "WSHHHSHSHSHSH" out of the horns. It's very yucky. These are $5 ABS horns and I can tell by looking for 5 seconds, they are NOT shaped right.
Oh well. It's for dance parties and I don't think they'll care a whole lot.
Pictures? Pictures coming.
Thanks again!
I actually discovered that if I take a piece of foam left over from the project, and shape it to fit the throat of the horn, and then jam it in there, it gives about the attenuation I want.
I'm afraid I have neither the money nor the time to spend getting L-pads, and I suspect they wouldn't give the range I wanted anyway; it doesn't matter though, my problem is basically solved.
I spent less than $130 on all the drivers for these boxes, and when you wrap it up to high SPLs, it really shows, especially to people who are spoiled like me.
The higs and mids sound like someone is going "WSHHHSHSHSHSH" out of the horns. It's very yucky. These are $5 ABS horns and I can tell by looking for 5 seconds, they are NOT shaped right.Oh well. It's for dance parties and I don't think they'll care a whole lot.
Pictures? Pictures coming.
Thanks again!
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.