I'm designing a 3-way box, and for the 4" speaker (which will be the mid-range speaker in the box) I will use a full range with crossover, and I would like this specific speaker to be in a sealed box, so how can I design a sealed box for a mid-range speaker?
I will use a GHXamp speaker from Aliexpress for this project
I was thinking about using WinISD to do it, but I have my doubts...
I was thinking about using WinISD to do it, but I have my doubts...
I will use a GHXamp speaker from Aliexpress for this project
I was thinking about using WinISD to do it, but I have my doubts...
I was thinking about using WinISD to do it, but I have my doubts...
Treat it as an ordinary woofer. You need Thiele-Small parameter for that.
Use WinISD without hesitation, you will get good results.
Winisd is not just for bass drivers. The difference between bass and midrange is mostly a label; they are the same kind of situation, if using cone drivers for both.
However, you probably don't need much low frequency extension from a midrange. So you don't need to use an enclosure big enough to give the low end roll off that a bass driver would want. The crossover will cut the low end off, in any case. Winisd will allow you to see this; the difference is your understanding of how to use/apply what it models, to suit your own application.
Though there are other types of good midrange chambers to consider, which winisd may not model so well. Such as aperiodic. In fact because much bass extension is not often needed, some people would even advocate leaving it open at the back. Software us useful, but the designer needs to be the decision maker.
However, you probably don't need much low frequency extension from a midrange. So you don't need to use an enclosure big enough to give the low end roll off that a bass driver would want. The crossover will cut the low end off, in any case. Winisd will allow you to see this; the difference is your understanding of how to use/apply what it models, to suit your own application.
Though there are other types of good midrange chambers to consider, which winisd may not model so well. Such as aperiodic. In fact because much bass extension is not often needed, some people would even advocate leaving it open at the back. Software us useful, but the designer needs to be the decision maker.
Ideally you want a closed box that generates a Q between 0.5 and 0.707, but for midrange use consider the XO frequency, it may allow a smaller box.
And i would make an “XRK Dagger shape… essentially a heavily tapered half-wave TL. I like to use heavily tapered quarter-wave midTLs.
The goal is for the midTL to becomenear aperiodic (full aperiodic is hard)
dave
And i would make an “XRK Dagger shape… essentially a heavily tapered half-wave TL. I like to use heavily tapered quarter-wave midTLs.
The goal is for the midTL to becomenear aperiodic (full aperiodic is hard)
dave
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I'm doing the sealed box project at winISD, what would be the FSC for this type of speaker? I will use the Lowpass filter at 7000 Hz and Highpass at 1000 Hz (which are the crossover parameters
FS (Resonant Frequency): 94 Hz (Resonant Frequency)
QTS (Total Quality Factor): 0.72
VAS (Equivalent Volume): 4.6 liters (Equivalent Volume)
QES (Electrical Quality Factor): QTS / QMS (mechanical quality factor) = 0.72
QMS (Mechanical Quality Factor): QTS / QES = 0.72
RE (Coil Direct Current Impedance): 4 ohms (Nominal Impedance)
SPL (Sensitivity): 88 dB ± 3 dB
BL (Engine Strength): (1/QTS) * (FS/RE^2) = (1/0.72) * (94/4^2)
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I was under the wrong impression that you want to use the 4-unch driver all the way down in the frequency and use lowpass filter only.
With highpass at 1000 Hz you don't need calculating the closed box - any small closed box volume will do.
Why so high crossover frequency (1000 Hz)? Any 4-inch driver will work at least from 300-400 Hz.
Because I want to use these crossovers and in their description it says that the midrange filter is 1000hz
https://a.aliexpress.com/_mNki0oq
I think they have chosen those frequencies to get the component cost down [ copper is expensive] so they can sell them cheap. I wouldn't be using them and I'm a near enough good enough sort of speaker builder. Any decent 110mm driver can be crossed at about 400/500Hz easily, even with first order. Some of the better drivers need no XO at all and can be run full range so long as the power fed to them isn't excessive. I'm with Dave in that a closed box Q of .055 to 0.7 is better but you can go bigger or smaller volume within reason.
PVC pipe the full depth of your box, open at the back and filled with polyfill or wool works too
EDIT
Links to the driver would be appreciated but with those specs a (Vb = Vas) would be my own starting point and XO at (Fs * 4) so 350 to 400Hz at a wild guess
PVC pipe the full depth of your box, open at the back and filled with polyfill or wool works too
EDIT
Links to the driver would be appreciated but with those specs a (Vb = Vas) would be my own starting point and XO at (Fs * 4) so 350 to 400Hz at a wild guess
As it happens I have used those little drivers, or very similar; they are OK but I only buy them when on sale.
https://www.jaycar.com.au/woofer-midrange-speaker-driver-4-inch/p/CW2190
Can easily handle a low XO if using a two element high pass but I usually use two of them ( 8R in parallel) as they aren't all that efficient.
They are sold at Jaycar here in Australia as "Own brand" drivers and I put two drivers in as big an enclosure as the box will stand or about 5 litres if on their own. Plus or minus a couple of litres doesn't make much difference as a midrange. Take the discussion of crossovers to the Multi-Way section of the forum but total box size is more dependent on which woofer you are using but with that driver use at least an 8 inch and can go up to a 10 or twelve easily. MTM I've used 2 or 3 *8" woofers
https://www.jaycar.com.au/woofer-midrange-speaker-driver-4-inch/p/CW2190
Can easily handle a low XO if using a two element high pass but I usually use two of them ( 8R in parallel) as they aren't all that efficient.
They are sold at Jaycar here in Australia as "Own brand" drivers and I put two drivers in as big an enclosure as the box will stand or about 5 litres if on their own. Plus or minus a couple of litres doesn't make much difference as a midrange. Take the discussion of crossovers to the Multi-Way section of the forum but total box size is more dependent on which woofer you are using but with that driver use at least an 8 inch and can go up to a 10 or twelve easily. MTM I've used 2 or 3 *8" woofers