Hi !
I'm building a passive subwoofer for my home theatre and also for listening music (I don't know if it's the right place to post).
My amp will never be above 120 W (i think). Just in case I push the value for 150W.
My constraint are :
1 - High quality sound (highest i can)
2 - 20 - 250 Hz (closest i can)
3 - Around 100€ for the driver (max 150€)
4 - Box max dimensions (inside) : 550 x 500 x 2000 mm
(I have dayton audio speaker that Kirby Meets Audio designed on youtube, those are quite great but it lacks of bass)
----------------------
I found (soundimorts.eu) :
73€ - Dayton Audio SD270A-88 10" (Green)
149€ - Dayton Audio DCS305-4 12" (Blue)
109€ - Dayton Audio SD315A-88 12" (Red)
On winIsd, for a ported enclosure :
Budgetwise : SD270A-88 but too high above Xmax (at 120W)
So, Budgetwise 2 : SD315A-88 but too higher than Xmax (at 120W)
Last choice : DCS305-4 almost down to where I want, spl, group delay, cone excursion, rear port air velocity OK !
--> 120L box, tuned at 23Hz
--> 500x40 mm port (lenght 825.8 mm) BUT the 1st port resonance : 208Hz ; is not an octave above my desired LP filter.
And then, I'm completely lost on the crossover design, I made a 4th order, but it seems that it will cost so much...
So here are my questions :
- Any Ideas of other greater drivers ?
- Does a subwoofer need to go as high as 250Hz ?
- Could you help me design a low budget crossover ? (I don't have much experience, I'm learning everything to achieve it)
My WinIsd files are also attached.
It might be too difficult to meet all these goals but I'm willing to get as close as I can !
Thank you very much for any answer !
Olamm
I'm building a passive subwoofer for my home theatre and also for listening music (I don't know if it's the right place to post).
My amp will never be above 120 W (i think). Just in case I push the value for 150W.
My constraint are :
1 - High quality sound (highest i can)
2 - 20 - 250 Hz (closest i can)
3 - Around 100€ for the driver (max 150€)
4 - Box max dimensions (inside) : 550 x 500 x 2000 mm
(I have dayton audio speaker that Kirby Meets Audio designed on youtube, those are quite great but it lacks of bass)
----------------------
I found (soundimorts.eu) :
73€ - Dayton Audio SD270A-88 10" (Green)
149€ - Dayton Audio DCS305-4 12" (Blue)
109€ - Dayton Audio SD315A-88 12" (Red)
On winIsd, for a ported enclosure :
Budgetwise : SD270A-88 but too high above Xmax (at 120W)
So, Budgetwise 2 : SD315A-88 but too higher than Xmax (at 120W)
Last choice : DCS305-4 almost down to where I want, spl, group delay, cone excursion, rear port air velocity OK !
--> 120L box, tuned at 23Hz
--> 500x40 mm port (lenght 825.8 mm) BUT the 1st port resonance : 208Hz ; is not an octave above my desired LP filter.
And then, I'm completely lost on the crossover design, I made a 4th order, but it seems that it will cost so much...
So here are my questions :
- Any Ideas of other greater drivers ?
- Does a subwoofer need to go as high as 250Hz ?
- How to define the 1st port resonance ? (I read that this should be 1 ocatve higher than the LP filter)
- How to design better to meet all the requirements ? (1st port resonance, cone excursion, group delay, ...)
- Could you help me design a low budget crossover ? (I don't have much experience, I'm learning everything to achieve it)
My WinIsd files are also attached.
It might be too difficult to meet all these goals but I'm willing to get as close as I can !
Thank you very much for any answer !
Olamm
Forget about passive L-C high-pass filter as subwoofer crossover - it is wrong. Subwoofer should work below 100 Hz. Your crossover frequency is unusable high at 550 Hz.
You need active (electronic) crossover, or at least passive RC line-level low-pas filter.
You need active (electronic) crossover, or at least passive RC line-level low-pas filter.
For subwoofer not to be localised, it has to be crossed low path steeply at 150Hz. Read pages on my blog.
If you plan on shallow passive crossover, you must cross substantially lower, 100Hz or lower, like Sonce said, otherwise you will have midbass comming out, which is undesirable.
If you plan on shallow passive crossover, you must cross substantially lower, 100Hz or lower, like Sonce said, otherwise you will have midbass comming out, which is undesirable.
Passive crossovers for subwoofers are not a good idea because you need very large inductors. Large inductors are either lossy (air-cored with very many windings), or have magnetic-hysteresis nonlinearity problems (iron core). Also don't forget that most subwoofers are less sensitive than main speakers, which means you need more power than you expect. And you may end up wasting significant power in an attenuator for the upper frequency range in order to match the sub level to the mid-woofer level.
You should look at using a separate amplifier - even a smallish one of 100-200W - and an active crossover. If you want to build just a box but not the amp, you can get cheap plate amps for subwoofer use that even include a crossover for you.
Your subwoofer needs to reach up as high as the bottom of the range your main speakers can do. Even if they're fairly small, they can probably do 100Hz, right? So pick a crossover point somewhere around there.
You should look at using a separate amplifier - even a smallish one of 100-200W - and an active crossover. If you want to build just a box but not the amp, you can get cheap plate amps for subwoofer use that even include a crossover for you.
Your subwoofer needs to reach up as high as the bottom of the range your main speakers can do. Even if they're fairly small, they can probably do 100Hz, right? So pick a crossover point somewhere around there.
I would also strongly advice against passive crossovers that low, better to use an active analog crosover or dsp, or a plate amp (Hypex) but keep the plate amp outside the box, plate amps don't live as long as the sub will and when the plate amp dies, the cabinet becomes useless if you can't find the exact same one (due to the cutout)
For driver, the SB Acoustics SB23MFCL45-4 fits your need, except that the needed box is much smaller than you can. 35L will be enough, but you will need a long vent (a folded slot or so) to tune it that low. You can buy it for 125€ at soundimport, and SB drivers are high quality, often better than Dayton (that are also very good).
For driver, the SB Acoustics SB23MFCL45-4 fits your need, except that the needed box is much smaller than you can. 35L will be enough, but you will need a long vent (a folded slot or so) to tune it that low. You can buy it for 125€ at soundimport, and SB drivers are high quality, often better than Dayton (that are also very good).
Thanks for your answers !
Understood ! I will look for a separate amplifier and an active crossover (it's sad that it's "impossible" to make a passive crossover...).
Here's my main speaker design, there are 2 of them (I need to rearrange the crossover to get a bit more bass since I've tested it)
So, yes my main speaker goes around 100Hz. I was thinking that letting it go around 150Hz-250Hz would be more efficient and clear (that's why 20Hz - 250Hz). Is it a good solution ?
I will check the SB Acoustics SB23MFCL45-4 and think about the port lenght !
Let's set a goal of 20Hz - 150Hz (too high ?), which amplifier/crossover would you recommend ? (I will do my research on my own also)
Understood ! I will look for a separate amplifier and an active crossover (it's sad that it's "impossible" to make a passive crossover...).
Here's my main speaker design, there are 2 of them (I need to rearrange the crossover to get a bit more bass since I've tested it)
So, yes my main speaker goes around 100Hz. I was thinking that letting it go around 150Hz-250Hz would be more efficient and clear (that's why 20Hz - 250Hz). Is it a good solution ?
I will check the SB Acoustics SB23MFCL45-4 and think about the port lenght !
Let's set a goal of 20Hz - 150Hz (too high ?), which amplifier/crossover would you recommend ? (I will do my research on my own also)
Maybe it's cheating, but I use one of these to crossover my passive sub. I cross it at 13Hz...
https://www.behringer.com/product.html?modelCode=P0132
https://www.behringer.com/product.html?modelCode=P0132
I use these as well.
Crossing at around 80 to 120Hz.
Recently went digital tho so the unit now does for my party system.
Amplifiers are relatively cheap and the CX2310 was cheaper than a pair of good passive XOs for 8R drivers at 120Hz.
Large value inductors with very low DCR are very expensive although you could wind your own the insulated copper wire isn't cheap.
Crossing at around 80 to 120Hz.
Recently went digital tho so the unit now does for my party system.
Amplifiers are relatively cheap and the CX2310 was cheaper than a pair of good passive XOs for 8R drivers at 120Hz.
Large value inductors with very low DCR are very expensive although you could wind your own the insulated copper wire isn't cheap.
LOL no not near flat anyway. It will certainly wiggle at 5 Hz like my other speakers though. It's just so the slope works... It's not brick wall filter at 13Hz... It's just there to fill in sub 32Hz and I don't really want to hear it above that... It feeds a Yorkville AP1200 set as a 950W bridged amp into an 8 ohm 15 inch car sub. It's plenty for a 12x18 foot room :") The vented box is now "sealed" with a pool noodle.
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I've looked the entire day for informations and how to use active crossover, it seems wonderfull, but too expensive, I would need 2 CX2310 for a 5.1 HC.
I will use a plate amplifier Only for my subwoofer, it usually have a built in crossover and I don't really need power.
Is 100W ok ? Do I need more ?
What do you think about Dayton Audio DTA 100LF or TPA sw25f ?
Do you have any better near the same budget ?
I will use a plate amplifier Only for my subwoofer, it usually have a built in crossover and I don't really need power.
Is 100W ok ? Do I need more ?
What do you think about Dayton Audio DTA 100LF or TPA sw25f ?
Do you have any better near the same budget ?
I do not know anything about your main speakers, or room, or amplifiers you use, but consider building two subs. If you have space, place them right under the main speakers. If your main speakers are bookshelf, even better. You get symetrical look, better bass, you can cross higher, and so on...you can even go passive. But the subs must be placed under the main speakers.
Since you sound like you could use the amp as well. These might be the next best thing since the invention of the subwoofer. This side of about 1500 CA anyway. I pushed the button on one to test out the waters, a second may soon follow its way in to my listening room.
The FA251 250 x1 with all the filters and boost you would need http://www.troelsgravesen.dk/FUSION_FA251.htm
I heard them in some NAD amps, Hypex are real work horses and stay cool, and up there with cutting edge D stuff.
I was going to go with a Crown XLS (which is a very good but slightly different route) but I wanted the extra versatility the Hypex offers especially eq, my subs will fail without a few db of boost to sound right. Despite the eq boost I think the Hypex will do much better than the crown, also despite having less power that the 1500 crown.
I am under the impression they make rock solid sub amplification.
I just hope there are no windows hang ups being the FA line is still relatively new.
So far its looking like great bang for the buck. Plus I love how they are going to custom fit and integrate with my rack. Pictures later as always. they are enet surplus (not mine)
The FA251 250 x1 with all the filters and boost you would need http://www.troelsgravesen.dk/FUSION_FA251.htm
I heard them in some NAD amps, Hypex are real work horses and stay cool, and up there with cutting edge D stuff.
I was going to go with a Crown XLS (which is a very good but slightly different route) but I wanted the extra versatility the Hypex offers especially eq, my subs will fail without a few db of boost to sound right. Despite the eq boost I think the Hypex will do much better than the crown, also despite having less power that the 1500 crown.
I am under the impression they make rock solid sub amplification.
I just hope there are no windows hang ups being the FA line is still relatively new.
So far its looking like great bang for the buck. Plus I love how they are going to custom fit and integrate with my rack. Pictures later as always. they are enet surplus (not mine)
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My personal preference is active bi or tri amp configuration, mosfets for the highs and mids and digital for bass/subs. tubes also for the ribbon tweeters - they seem to stand out the best. But remember to calculate the woofers enclosure when designing the lowpass subwoofer is filter. Vented enclosures already have a 4th order high pass filter. Such that you can just concentrate on what the low pass needs to be. Or even add an active 2nd order that is aligned to the vented enclosure to get a 6th order alignment. B&W did that to their 801 matrix series, they had used a 6th order alignment, and used a tuned vent to get a much better bass range (F3 dropped from 32 hz to 20 hz and reduced cone extension and increased power available before reaching overload conditions. ) interestingly enough they had the foresight to design that in the earlier series such all you needed was the active filter module and the right vent tuning . Very low upgrade costs. Enclosure, speaker driver and passive x-overs stayed the same
But I think the most cost effective is active subs. The amount of good components needed for a passive system isn't worth the time.
I think Dayton has subwoofer amp kits, with programmable x-over and gain.
Passive x-overs are expensive , mainly because the power requirements needed for low frequencies . Such that inductors will have iron, lots of copper and caps will need to be high voltage. Matching the speakers efficiency is also an issue needing passive padding, more high powered capable components . All the active sub systems these days are digital, digital is by far the best for reproducing solid low distortion bass that's 1/10 the costs of analog systems. Some people might argue, and I can understand their need to believe their analogs systems are better. I have a mosfets that do around 300 watts (.01%THD) and I have digitals at 500watts.(Same .01%THD) Sonically no difference other than price, the digitals being quite a bit cheaper. Fun to show off mosfets though being very large heat sinks. Digitals just look too wimpy, so their buried in the active cross modules.
But I think the most cost effective is active subs. The amount of good components needed for a passive system isn't worth the time.
I think Dayton has subwoofer amp kits, with programmable x-over and gain.
Passive x-overs are expensive , mainly because the power requirements needed for low frequencies . Such that inductors will have iron, lots of copper and caps will need to be high voltage. Matching the speakers efficiency is also an issue needing passive padding, more high powered capable components . All the active sub systems these days are digital, digital is by far the best for reproducing solid low distortion bass that's 1/10 the costs of analog systems. Some people might argue, and I can understand their need to believe their analogs systems are better. I have a mosfets that do around 300 watts (.01%THD) and I have digitals at 500watts.(Same .01%THD) Sonically no difference other than price, the digitals being quite a bit cheaper. Fun to show off mosfets though being very large heat sinks. Digitals just look too wimpy, so their buried in the active cross modules.