I see many nowadays hi-end speakers use x/o in very low point with the midranges of cone type. However, to my understanding, another reason is most bass drivers have relatively flat impedance at 100 Hz region while at 500 Hz, it may need to be flattened the impedance with some circuits such as the zobel/ impedance equalization circuit.
Please find attached for the drawing of cabinet. Please note that the bracings are ignored here since I don't want to confuse anyone now, but they will be added in actual building. For crossover, I haven't designed it yet but the plan is to use 12dB/octave in every section. In fact, I have crossover networks of the AL6 speakers, I'm hesitating to use them, so I could save the money on mid-to-high crossovers. I have to ask you your opinion too. The sensitivity and L-Pad are haven't yet measured, too.
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Sure. I've successfully built them. The picture is on attached. They're nice sounding now, but I need a little more bigger, so I wish to start this project.
As you can see that all speakers I built were using dome midranges. This time, I'd like to try with cone mids plus low x/o points.
I'd love to hear all comments. Thanks
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Nice build, good job on that. Any measurements?
Back to your new project it seems you have decided already so just go for it.
I don’t think it’s going to be good though but you learn by doing so the experience of it is useful. Do you plan to parallel or serial connect the pair of 12s?
Crossover at 100hz is still a bad idea, you leave all the hard work to the flimsy car mid.
Back to your new project it seems you have decided already so just go for it.
I don’t think it’s going to be good though but you learn by doing so the experience of it is useful. Do you plan to parallel or serial connect the pair of 12s?
Crossover at 100hz is still a bad idea, you leave all the hard work to the flimsy car mid.
Please see attached for the measurement and note that the 100 Hz bump might be caused by room, I had tried on other speakers and they were the same. And sorry, I'm not good at adjusting the scale. If something went wrong, please suggest me.
Parallel connecting since they are 8 Ohms, thus, 4 Ohms might be better than 16 Ohms, in my opinion. At least, it can save money from spending on larger coils.
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That graph is what you get with car drivers, it cannot sound very pleasing, im expecting boomy and harsh and I am afraid your next project will turn out the same way with your current design of. You need to read up on baffle step effect and especially when using car drivers this is going to be a problem. The 100Hz crossover you have in mind will further enhance that problem. You want to have more sensitivity in 200-500hz area and in the below 100Hz area. A good 12" will give you that, but only with the right crossover and box tuning.
No, bass isn’t boomy and harsh at all. As stated above, the measured bump at 100 Hz is the result of room gain. I had measured even commercial speakers and they were similar. In fact, I have the data sheet of these car woofers. It has recommendation of box volume (closed box) from 0.75, 1, 1.25 and 1.5 cu.ft. And I chose 1.5 cu.ft. for them resulting in an over-damped response of Q = 0.49! Hence, no boomy bass is detected outside measurement, I swear. Thanks for good suggestion though.
Unbelievable, my another thread is closed!
I guess this thread may be the reason.
To moderator, please read these threads again. You will notice that these two threads may be analogous. But, if you look carefully, they are not alike.
Although the introduction may be resemble, this thread actually focus on the CABINET building as you can see there are plenty of VOLUME units, whereas that thread is focusing on CROSSOVER building, the RESISTOR is the main discussion.
Please reconsider.
presscot
I guess this thread may be the reason.
To moderator, please read these threads again. You will notice that these two threads may be analogous. But, if you look carefully, they are not alike.
Although the introduction may be resemble, this thread actually focus on the CABINET building as you can see there are plenty of VOLUME units, whereas that thread is focusing on CROSSOVER building, the RESISTOR is the main discussion.
Please reconsider.
presscot
Well if you look at your recent five threads in multiway sub forum they are all about the same. Parallel vs serial connecting cheap car audios to make them fit home use. Strange crossover discussions was just a bonus. I think you should spend some time reading all the input you got, consider what it means, then read the stickies, watch some YouTube channels, read some more then just buy something and try whatever you want. Then come back and tell us how it all went. No need for more threads or posts about these topics. It’s loudspeaker design 101. Buy the book. Buy some kits. Don’t take it the wrong way, you asked for advice and you got plenty. Why not take them.
Your other thread was closed because it had "run its course".
In other words, you kept on ignoring advice and insisting on repeatedly introducing the same poorly informed ideas that had already been rejected by other members.
On the plus side, if it is attention you seek, your threads are proving a huge success!
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I believe you wanted a serial resistor of the same power as two parallel 12”. That would require a head sink wouldn’t it. I still think you should use water cooling instead.
I also think these threads are great learning for others and I wouldn’t close them, they are very educational. I wonder who rate them terrible. I agree with OP, 10000 watt is nothing to worry about.
Im not sarcastic. If he really want to use a 2ohm resistor in series with two 4 ohm parallel 12" 84dB drivers crossed at 100Hz (giving maybe a 72dB system sensitivity?), that resistor really must be able to take a beating if any sound are to be coming out of his open windows at all. I think water cooling is the only way to handle that amount of power without burning down the house (remember we need +40dB in this case...).
Well maybe a little sarcastic. Personally I wouldn’t go on with the current design. But for getting some hands experience why not? Pragmatic approach may in many cases weigh more than academic. Maybe it turn out to be a great speaker after all. Who knows, some speakers are magic, and by accident. @OP do what you want and please share the results after. Don’t listen to the conservative haters. You have a few spare amps. If you blow one or two who cares. Then connect them in series. No dramatic damage to really. Just make sure that resistor is really cooled off somehow, you don’t want the crossover to catch fire in your house.
To those that disagree with the way this thread is developing, cool it. You have other options.- Status
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