Hi Guys, I intend to build 4 way active horn speaker ,hopefully if possible something similar to OMA top of the line if I could get hold of plans for the conical horns. Otherwise I'd build 4 way Horn speaker on close enclosure with some matching wooden horns. I'd appreciate your advice concerning the bass which I'd like it to go down as possible to 20Hz.The options are AEspeakers TD-18H,BMS 18S430V2, ,Ciare 18SW,Beyma 18PWB1000FE,JBL 2245H,Mccauley 6174 ,however the cheapest driver is $400 and goes up to $800 per unit .On the other hand I saw a driver from Dayton Audio PA460 out ofwhich it's FR:26Hz-2kHz,97.8db,Fs-28.3Hz which merely cost $180 per pair ! Could someone let me know if the above Dayton is so inferior to the others or would I get 99% similar quality tight base without distortion ? I'd appreciate any solid recommendation even completely different ,since I haven't had the chance to hear any of the above drivers,hence am clueless which one will give me the best results !
The PE model PA460-8, with a QTS of .33 and FS of 28 Hz is not designed to play flat to 20 Hz. Few woofers can do that with any real volume output level. Even in a 10 cu. ft. ported box tuned lower than recommended, you are at F3 around 26 -28 Hz and are falling off rapidly below that (24db/octave). With room gain you will likely be down 8-12 db at 20 Hz. Doesn't mean the PA460 is a bad driver, it's great for the money, just not designed to do what you are asking for. And Xmax is a bit limited at 6 MM. Got to move a LOT of air to play loud at 20 Hz.
A better PE selection would be P/N 295-518 (UN18-22) Ultimax dual Voice coil 18". With an FS of 19.5 Hz, and an in box QTS around .55 or in a 120 liter stuffed box have an FS of 26 and rolls off at half the rate of the PA460. And the UN18 has an xmax of 22 MM, nearly 4 times that of the PA 460. So with the same room gain it should be close to flat at 20 Hz. Since you are planning an active crossover, the UN18 can be set up to work well up to 300 Hz or so. Just my $0.02 worth. But all this output in a small box comes at a price, $325.00 each!
A better PE selection would be P/N 295-518 (UN18-22) Ultimax dual Voice coil 18". With an FS of 19.5 Hz, and an in box QTS around .55 or in a 120 liter stuffed box have an FS of 26 and rolls off at half the rate of the PA460. And the UN18 has an xmax of 22 MM, nearly 4 times that of the PA 460. So with the same room gain it should be close to flat at 20 Hz. Since you are planning an active crossover, the UN18 can be set up to work well up to 300 Hz or so. Just my $0.02 worth. But all this output in a small box comes at a price, $325.00 each!
Dear John, Thanks for your illuminated reply.I read it's data and it's quite impressive apart from it's low SPL-only 88.6db which is disappointing factor as it diminishes it's quality. One guy on usspeakers reviewed it and said:" I have to give it 3 stars however due to my driver having an issue with upper and lower bass. With lower bass around 25hz and below the distortion was far more audible than the actual bass. I had to cross it over very low to avoid a muffled rattling sound on the upper bass. 80hz was a real issue and even with a 4th order active filter I had trouble finding any real usefulness for this subwoofer given the limited range of the one I recieved " that was the only negative review there. I checked all the drivers I mentioned earlier including BMS,Radian and AESpeakers TD-18H and it seems that this model of Dayton UM18-22 has better data than all the above mentioned -can it be or did I miss something ? Are there any better 18' drivers which can go flat 20Hz with better data and most importantly better performance at a reasonable price ?
That's the engineering challenge.... efficiency versus box size/efficiency. And, do you REALLY need to play flat at 20 Hz. To do it right at a reasonable sound level is an expensive proposition. Other than some pipe organ and or movie sound effects, there is not a lot of material down there. A good compromise is flat to 3 db down in room in the area of 32 Hz.
Then you get down to where this system is going to be used, big room, small room.... what are your priorities? How much are you willing to spend?
Not glamorous questions to be sure, but very important!
Then you get down to where this system is going to be used, big room, small room.... what are your priorities? How much are you willing to spend?
Not glamorous questions to be sure, but very important!
Might a HiFi build that can go this low, be well served by a car subwoofer for that last 10hz. Something disposable.. Car subs are for getting low with small boxes. Their compromised such that 200hz is about as far up as they can reach, but for this duty that's Okay.
I have $200US JBL 12s in 95L with a port tuned below 24hz. This was the box winisd gave me as optimum for the driver. It's flat at 30 but by 22 I'm 3db down. It's just drivers from a twin box I got used at $75US, Not specially chosen. You could surely stay flat to 20hz with a 15" or 18"
Nothing defined is going to happen at 20Hz. The HiFi speakers would do everything really, with the sub just there for the heavy lifting. Slinging vast amounts of air about. Giving reverence to your 18Hz pipe organ recordings.
I use mine to 100hz, in a FAST. I have always found JBL subs rather woolly in cars, but these add great weight. A real solidity. Even if not the tightest. Being a 12 in a 4" ported box.
It could be amusing to bottom one out. Even to blow it. It's cheap, and won't effect your main speakers. You might not even miss it, until you watch earthquake again.
Edit: You could power these effects speakers from a half kilowatt PA amp. Worth peanuts beside a hifi amp that can do that much work.
Last edited:
For the record, no woofer is flat in room to 20 Hz. You are going to need significant EQ with any speaker that plays that low. Depending on how the room works out, you could end up cutting output at 20 Hz, or just below, or just above, significantly.
Obviously worth calculating the excursion vs. output levels though.
Obviously worth calculating the excursion vs. output levels though.
Thanks for all the responses.
John,based on what you say,if I make a compromise and pick a driver that goes down to around 32Hz-I could still pick the cheap Dayton PA460 which goes further down to 26Hz,although I must admit that UM18-22 have much better data and probably sounds better ,but it's lack of SPL frightens me a bit.Are there any other drivers with similar/better data and higher SPL ? I know that there are some prestigious brands such as Goto from Japan that couldn't care less for the formal data and their biggest drivers go down to 28Hz and still considered as one of the best(that is the rumor-I haven't had the chance to hear it).
Anyhow,had I not made any compromise up to let's say $750 per unit what driver that goes down to 20Hz would be the best one, bearing in mind I'm looking for beautiful tight bass down to 20Hz without any distortion on it's frequency spectrum whatsoever. My listening room is 3.5m*6.5m with 2.7m ceiling ? The reason for going active rather than passive is due to the possible "absolute" control with the way the whole set would sound including the low's of 20Hz.
John,based on what you say,if I make a compromise and pick a driver that goes down to around 32Hz-I could still pick the cheap Dayton PA460 which goes further down to 26Hz,although I must admit that UM18-22 have much better data and probably sounds better ,but it's lack of SPL frightens me a bit.Are there any other drivers with similar/better data and higher SPL ? I know that there are some prestigious brands such as Goto from Japan that couldn't care less for the formal data and their biggest drivers go down to 28Hz and still considered as one of the best(that is the rumor-I haven't had the chance to hear it).
Anyhow,had I not made any compromise up to let's say $750 per unit what driver that goes down to 20Hz would be the best one, bearing in mind I'm looking for beautiful tight bass down to 20Hz without any distortion on it's frequency spectrum whatsoever. My listening room is 3.5m*6.5m with 2.7m ceiling ? The reason for going active rather than passive is due to the possible "absolute" control with the way the whole set would sound including the low's of 20Hz.
For low frequencies you can take that spl number (quite often given at 1khz which is very far away from 20hz), and just throw it out the window.
What you need to look at is: sd (surface displacement), and xmax (cone travel, either specified one way, or p-p/peak to peak), aside from the usual fs, qts, vas and so on, pending on your needs or wants.
What you need to look at is: sd (surface displacement), and xmax (cone travel, either specified one way, or p-p/peak to peak), aside from the usual fs, qts, vas and so on, pending on your needs or wants.
KaffiMann's post is right on. The criteria you need to satisfy are how loud do you need to play cleanly at what frequency balancing box size and cost.
With active, taken to a bit of an extreme, you can force the PA460 to play down to 20 Hz. It would need to be in a stuffed sealed box and you would have to feed it with enough power to overcome the natural roll off that set up would have. Just guessing, it would require maybe 24-30 db of boost at 20 Hz. to do it depending on room gain. But once you do that, is it usable? The PA 460 has a clean one way volume of acoustic displacement of around 750 cc. The UM18 is around 2,700. Huge difference. So it is much easier for it (UM18) to play much louder. Also assuming a sealed box alignment. The UM18 would also require some boost, but no where near what the PA460 would require. The reason for the difference is the UN18 is designed for this kind of application, the PA460 is not. To get the most out of the UM18 is going to require 500-1,000 watts. That is because the UN18 design trades efficiency for the ability to play loud and low in a small sealed enclosure. The PA460 is designed to play loud from 40Hz up using the least amount of power in a medium sized ported box. You can go here and see how loud a woofer can potentially play at what frequency depending on the woofer size and Xmax.
Piston Excursion calculator
The UM will play ten times louder than the PA460.
With active, taken to a bit of an extreme, you can force the PA460 to play down to 20 Hz. It would need to be in a stuffed sealed box and you would have to feed it with enough power to overcome the natural roll off that set up would have. Just guessing, it would require maybe 24-30 db of boost at 20 Hz. to do it depending on room gain. But once you do that, is it usable? The PA 460 has a clean one way volume of acoustic displacement of around 750 cc. The UM18 is around 2,700. Huge difference. So it is much easier for it (UM18) to play much louder. Also assuming a sealed box alignment. The UM18 would also require some boost, but no where near what the PA460 would require. The reason for the difference is the UN18 is designed for this kind of application, the PA460 is not. To get the most out of the UM18 is going to require 500-1,000 watts. That is because the UN18 design trades efficiency for the ability to play loud and low in a small sealed enclosure. The PA460 is designed to play loud from 40Hz up using the least amount of power in a medium sized ported box. You can go here and see how loud a woofer can potentially play at what frequency depending on the woofer size and Xmax.
Piston Excursion calculator
The UM will play ten times louder than the PA460.
As mentioned earlier.... One philosophy is to construct high quality front stereo speakers with bass down to ~30Hz as measured at the listener using "musical woofers", and add 2 subwoofers like the UN18-22 carefully placed around the room equalized to reduce bass modes. "musical woofer" = modest Mms(<200g), modest Le(<1mH), no cone breakup under 1kHz...
Consider:
1) design the main front stereo speakers using musical 15" - 18" woofers
2) plan to add 1-2 UN18-22 subwoofers with room mode equalization
Dr. Geddes "Consider the low frequency region in a small room. If this room has a small amount of damping it will have a very discrete modal structure with an associated resonant modal sound character. No single source placed in this room would ever sound correct – not dipoles, monopoles, low frequency horns. In essence, the room dominates the situation over the source characteristics making all bass sounds in this region colored and not lifelike. Each mode accentuates the sound level when it is excited and diminishes the level where there are no modes. The sound is either “boomy” or “dead” with no happy medium in between. "
Consider:
1) design the main front stereo speakers using musical 15" - 18" woofers
2) plan to add 1-2 UN18-22 subwoofers with room mode equalization
Dr. Geddes "Consider the low frequency region in a small room. If this room has a small amount of damping it will have a very discrete modal structure with an associated resonant modal sound character. No single source placed in this room would ever sound correct – not dipoles, monopoles, low frequency horns. In essence, the room dominates the situation over the source characteristics making all bass sounds in this region colored and not lifelike. Each mode accentuates the sound level when it is excited and diminishes the level where there are no modes. The sound is either “boomy” or “dead” with no happy medium in between. "
For the record, no woofer is flat in room to 20 Hz. You are going to need significant EQ with any speaker that plays that low. Depending on how the room works out, you could end up cutting output at 20 Hz, or just below, or just above, significantly.
Obviously worth calculating the excursion vs. output levels though.
Just have to mention:
By some insane stroke of luck the in-listening-position frequency response with my 4 x 15" subs is within +/- 2db from 14hz to 90hz, with no eq!
Completely unexpected, was prepared to make a lot of corrections, and expected subs to roll off slow after 26hz.
I think surface displacement is the secret sauce, get enough of it and some room modes just get drowned out....
Most of my in-room trouble is 120-400hz which looks like a skate park though.
The Dayton PA460 seems to want a really big box to deliver, but it's quite good to 24hz (110db/100w/2pi). I think the resistive slot port will help it go lower than simulated.
Still at 260 liters each for the PA460, I'd much rather keep what i have (129 liters internal volume x 4).
Attachments
Last edited:
many thanks,however those companies only make subwoofers/drivers for cars rather than Hi End Home sets and I've never heard of them in relation to Home Audio ! The stereointegrity brand seems exteremely expensive for car's subwoofer/driver the first one is slightly cheaper,but am clueless about it's qualities and reputation as to Home Hi End drivers in comparison to Radian,Acoustic Elegance ,Precision Devices,Mccauley,BMS,Beyma and even Dayton Audio ?! Are you sure any of them manufacture subwoofer/drivers for home -4-16 Ohm with excellent Fs,Qts,Xmax,high SPL going flat to 20Hz ?
IMO "flat to 20hz" is not the ultimate goal for everyone.
Have you analyzed your music collection?
I found there was little need for much under 26hz, and that was for very good quality piano recordings. Modern music, even quite "bass heavy" stuff does not have a whole lot under 35hz.
I went for a "slow downwards roll of" kind of thing, and it ticks all my boxes, sounds great.
Simulation for: Flat to 40-45hz then slooooow roll off = really nice after the sawdust has settled. Also takes much less space than going for "max output at 20hz".
Have you analyzed your music collection?
I found there was little need for much under 26hz, and that was for very good quality piano recordings. Modern music, even quite "bass heavy" stuff does not have a whole lot under 35hz.
I went for a "slow downwards roll of" kind of thing, and it ticks all my boxes, sounds great.
Simulation for: Flat to 40-45hz then slooooow roll off = really nice after the sawdust has settled. Also takes much less space than going for "max output at 20hz".
Aside from the BM and SHS series, Stereo Integrity's subwoofers are intended for home use. The car audio versions, you could say, would be Sundown Audio's offerings. (The owners of both companies are friends and business partners, so the parts are shared with changes in the voice coils, suspension, moving mass, etc).
I use one of Stereo Integrity's early 24" subs in my home system where it's had no problem outshining other drivers in comparisons I've made including, among many, a TC Sounds driver model that was Magico's choice in their original Q-Sub before TC Sounds went under and a couple of Acoustic Elegance subs (albeit, those were intended for OB use). There's no comparison with Dayton. (B&C's IPAL line would make for a better comparison to add to your list, but not at these lower frequencies.) With room gain, the response I enjoy is flat to 10Hz and likely below, but it's difficult to get accurate measurements below that. Couldn't tell you how loud it can go, though, as I only had a Radio Shack SPL meter handy the day I was having extra fun and pegged the needle full scale at 25Hz. I was so impressed that I picked up a couple of custom 24" units from them to use in some open baffle speakers I'm getting around to building at a glacial pace.
The extra displacement is always nice when I enjoy listening to apparently imaginary music:
Attachments
I have a commercial bass test CD full of tones and sweeps. The lowest tone on it is 30Hz. At which point my sub hasn't began to loose any volume. So I switch to bass driven music and get the mic out. Most tracks, heavy as they may seem, don't bother recording stuff below 50Hz. It would just suck the power out of the average car or kitchen radio, trying to make noise the speakers can't reproduce. So bringing forward the onset of distortion. Mainstream music needs to work with bookshelf speakers that could have a 70hz F3 or worse. So adding in 20Hz information is detrimental.
It's almost effects driven. I imagine lots of people dream of tort bass down to 20Hz. Isn't it a little unrealistic though, and choosing an 18 a good way of failing before you start. What could be flabbier.
It's almost effects driven. I imagine lots of people dream of tort bass down to 20Hz. Isn't it a little unrealistic though, and choosing an 18 a good way of failing before you start. What could be flabbier.
lots of music has content below 26hz.
If you listen to electronic, 10hz is not uncommon.
it is felt and create a presence hard to describe, removing it remove a vital element in the experience.
you do not think there is energy down there till you have a system that can do it and realize how much you missed all those years...
to have the effect, one have to listen bit loud, human ear can't hear 20hz unless it is at least ~80db (as per research on ear sensitivity)
since subsonic content is often 20 decibel down in the recording, one have to listen to 100db or so to get the intended effect...
My system was flat to 7hz and capable of significant output. (4x 18" subwoofer)
I think is important enough that I bought 2x more 18" and plan on buying 2 more for a grand total of 8x 18".
house shopping right now...
If you listen to electronic, 10hz is not uncommon.
it is felt and create a presence hard to describe, removing it remove a vital element in the experience.
you do not think there is energy down there till you have a system that can do it and realize how much you missed all those years...
to have the effect, one have to listen bit loud, human ear can't hear 20hz unless it is at least ~80db (as per research on ear sensitivity)
since subsonic content is often 20 decibel down in the recording, one have to listen to 100db or so to get the intended effect...
My system was flat to 7hz and capable of significant output. (4x 18" subwoofer)
I think is important enough that I bought 2x more 18" and plan on buying 2 more for a grand total of 8x 18".
house shopping right now...