All,
I have another dumb idea and I'd like to know why it wouldn't work. Or it might work, but something tells me this is too easy...
https://www.madisound.com/store/product_info.php?products_id=8988
Case of 30 for $60...
I'm thinking, for my intro into line arrays, that this would be a near-perfect driver. It's not one of those nice clean 3" drivers, but it has more bass, and it's still pretty small. It looks like it'll go low enough to cleanly mix with a sub. The harmonic distortion curves seem ok, but I also don't really have a reference as to what's good and what's bad.
So, the design is that driver, along with the (in)famous Goldwood GT-1005. Actually, I was planning on using the GT-1001 since I think the flush mounting looks awesome. Of course, I thought, for some reason, I had a frequency response graph for these tweeters, but without one I think I may have to pass..
The plan is to wire the 5.25"ers either 3 or 4 in series, those sets in parallel (16/side). If I ran this as a free-standing speaker, I'd run one set of 4 drivers as a 0.5 way for BSC, but I'm also thinking about making these into a Murphy corner-line array design. As sensitive as this tweeter is, I was thinking about running a single driver it in the middle of the array, a sort of a MMMMMMMMTMMMMMMMM design. Is this problematic?
I haven't thought much about the crossover yet, it doesn't seem like it would be very tough. I've been experimenting with 1st/2nd order low/high and 2nd/2nd. I'll probably need some other woofer correction, especially if I cross it pretty high, but it seems like these drivers are pretty damn usable for the price.
Let me know what you think.
Greg
I have another dumb idea and I'd like to know why it wouldn't work. Or it might work, but something tells me this is too easy...
https://www.madisound.com/store/product_info.php?products_id=8988
Case of 30 for $60...
I'm thinking, for my intro into line arrays, that this would be a near-perfect driver. It's not one of those nice clean 3" drivers, but it has more bass, and it's still pretty small. It looks like it'll go low enough to cleanly mix with a sub. The harmonic distortion curves seem ok, but I also don't really have a reference as to what's good and what's bad.
So, the design is that driver, along with the (in)famous Goldwood GT-1005. Actually, I was planning on using the GT-1001 since I think the flush mounting looks awesome. Of course, I thought, for some reason, I had a frequency response graph for these tweeters, but without one I think I may have to pass..
The plan is to wire the 5.25"ers either 3 or 4 in series, those sets in parallel (16/side). If I ran this as a free-standing speaker, I'd run one set of 4 drivers as a 0.5 way for BSC, but I'm also thinking about making these into a Murphy corner-line array design. As sensitive as this tweeter is, I was thinking about running a single driver it in the middle of the array, a sort of a MMMMMMMMTMMMMMMMM design. Is this problematic?
I haven't thought much about the crossover yet, it doesn't seem like it would be very tough. I've been experimenting with 1st/2nd order low/high and 2nd/2nd. I'll probably need some other woofer correction, especially if I cross it pretty high, but it seems like these drivers are pretty damn usable for the price.
Let me know what you think.
Greg
For a line array to work as a line array at high frequencies requires drivers to be no more (preferably less) than a wavelength apart, that is about 5/8 of an inch for 16K.
Line arrays generally use special horns that emulate the response of a ribbon driver for frequencies above 1000 to 2000 Hz.
The 5.25 would be OK perhaps to 2000 Hz from a line array standpoint.
Above that, they are quite ragged in response, then roll off anyway.
Line arrays generally use special horns that emulate the response of a ribbon driver for frequencies above 1000 to 2000 Hz.
The 5.25 would be OK perhaps to 2000 Hz from a line array standpoint.
Above that, they are quite ragged in response, then roll off anyway.
Less than a wavelength from diaphram to diaphragm or center to center?
I'll be searching, but any leads on building one of those special horns? Why do so many people (including some old Infinitys) use dome mids and the polycell tweeters considerably farther apart than that? The idea makes sense to me, but it seems like lots of designers seem to skip that rule.
What about putting one very high sensitivity tweeter in the middle of the array? Theoretically, So long as the 5.25" speakers are less than 6.78" apart (2000hz), then the line array shouldn't be "broken", right?
Greg
Centre to centre.
The spacing is only critical for multiple drivers (for example, two mids) which are reproducing the same frequencies. The mid-to-tweeter spacing is not critical because they reproduce different frequency ranges, so there won't be any interference between them. (However, the mid-to-tweeter spacing is important for other reasons related to crossover design etc.)
In theory, it could be made to work. You'll need to design the crossover's phase characteristics to properly integrate the tweeter and mids, as you would for a conventional mid-tweeter layout. Personally, I'd try to keep the driver spacing to 1/4 wavelength or less at the maximum frequency to be fed to the array. You may get away with more depending on the performance of the drivers.
Those drivers look a bit like they were designed to be installed in a console television.
I agree, but the price and frequency response curve seem to suggest that they're a half-step better than that. Plus the distortion curve seems to be at-or-below the going rate for that price range.
What I meant was, there's an old Infinity line array system that used a line of 6 mid-domes and 6 or 7 polycell tweeters, and within each line, the spacing was quite far apart. I wasn't describing the spacing between the mid line and tweeter line.
If I did go with the MMMMMTMMMMM design, I'd be worried about having awful vertical dispersion. If I went with a line of tweeters, I'd be worried about finding a dome (or ribbon) cheap enough to mount 5/8" C-C that could go down to 2khz. Would I be right in assuming that if tweets are spaced 10/8" C-C that I would have comb filtering problems at 10khz and up?
Greg,
Spacing of drivers on "regular" speakers may be arranged to avoid diffraction problems, or make the dispersion better in the crossover region. Sometimes an odd arrangement is chosen that is a compromise allowing the speakers to be used horizontally or vertically.
Your math seems OK, 6.78" center to center sounds right for 2K.
I have built "special horns" for line array use, based on Tom Danley's Paraline design used in his Genisis and Jericho horn and VTC's line array.
The VTC Paraline would be too narrow in vertical dispersion for home use.
The design could be modified to have more vertical dispersion, but a regular conical horn would be far easier for you to build.
Having tried line arrays for home use, I would not advise using them.
A Unity or Synergy horn design will give you pattern control with out all the comb filtering the line will have.
That said, I'm using a simple 2 way with subs for my home stereo, though I'd like a Synergy design, the cabinet depth and difficult crossover have kept them out of my living room.
I norder to keep costs low, use a vertical wide disperson piezo array for treble if you want to cross over low. Something like this : Goldwood GT-1016 2" x 5" Wide Dispersion Piezo Horn Tweeter
The Murphy Corner-Line-Array Home Page
this is an alternate view on the comb filtering. As the troughs are very high Q they should not actually be very noticeable as long as the general high frequency attenuation trend is equalized out. In a real room you get lots of cancellation causing similar comb filtering anyway. You want to use a smaller driver though as the horizontal dispersion of such a large driver won't be good, don't go >3" dia of the radiating surface (some drivers have large surrounds like mark audio).
*After messing around with peizos my conclusion was that they are completly not workable as tweeters due to very uneven frequancy response that would require digital filtering to correct.
this is an alternate view on the comb filtering. As the troughs are very high Q they should not actually be very noticeable as long as the general high frequency attenuation trend is equalized out. In a real room you get lots of cancellation causing similar comb filtering anyway. You want to use a smaller driver though as the horizontal dispersion of such a large driver won't be good, don't go >3" dia of the radiating surface (some drivers have large surrounds like mark audio).
*After messing around with peizos my conclusion was that they are completly not workable as tweeters due to very uneven frequancy response that would require digital filtering to correct.
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Sounds like a project I'm working on in the garage
I used those Sony 5" neo woofers and literally overlapped the frames so they are 5.58" center-to-center. The thin sheet metal frames help although I did cover them with plumbers putty to damp frame ring. The crossover at 4050 Hz at 12dB slope to those Audax 10mm tweeters for 50 cents a pop--all 48 of them. To protect the little tweets, I've used a 24dB/Oct filter at 4,200 Hz and spend my days waiting for the shipment to arrive.
My woofer line is 5 feet 7 inches tall and the tweeter line is 5 feet 8 inches tall. My woofer line hits the one wavelength at 2,420 Hz so I get some beaming there until 4050 Hz when it starts rolling off (Linkwitz-Riley -6dB XO type) I'll also get beaming at 10KHz+ from the tweeter line but such is life.
How do they sound? Well, I don't have the crossover parts yet but 48 tweeters running a test tone at 4,200 Hz will wake up the dead! I ran the 12 five inchers "full range" to break them in and check for leaks (sealed box) After a day or two, they seemed to sound better although they have no high treble. They are loud! They don't change their sound if I'm sitting or standing and have a really "big" sound to them.
Once I get the crossover parts in, I can build the filters and test the 6 foot tall monsters out. Their life is a "garage speaker" and I want to see if the vertical line array overpowers reflections from the cement floor and metal roof.
I went with the Sony 5 inchers since they have rubber surrounds, polypropylene coated paper cones and full metal grills to protect them from garage involved flying liquids, parts etc. The boxes are "PA style" with corner edge hardware, handles in the sides and 1.5" tall rubber bumpers at the corners so not to cave in the grills when/if it falls over. Eventually, a tapped horn sub will take over at around 70Hz to get the party going.
The object of my garage speaker mess is to see if they work decently enough in the acoustic hell of a cement floor/metal roof garage. I'll stack them on top of each other floor-to-ceiling, run them in mono and play a guitar through them. Infinite line array theory anyone?
If I actually like the sound of them and would feel the need to upgrade in a few years, I'd go with 3 to 4" woofers and keep the same tweets. The Dayton Audio 3.5" full range looks like a decent driver to take the place of the cheap 5" Sonys eventually.
After all, stuff a 100K speaker in a garage with a metal roof and it won't sound very good...maybe the line array will work, maybe it won't. Either way I'll have something very durable, takes up the floor space of a sheet of paper, very, very LOUD and the locals think it is the coolest speaker they've ever seen. There is something about a pair of speakers running 24 woofers and 96 tweeters that entertains people.
I'll let the world know how and if it works. One of the DIY'ers built something like it and said it sounded like a "velvet hammer". That free shipping from Parts Express takes a looooong time...
I used those Sony 5" neo woofers and literally overlapped the frames so they are 5.58" center-to-center. The thin sheet metal frames help although I did cover them with plumbers putty to damp frame ring. The crossover at 4050 Hz at 12dB slope to those Audax 10mm tweeters for 50 cents a pop--all 48 of them. To protect the little tweets, I've used a 24dB/Oct filter at 4,200 Hz and spend my days waiting for the shipment to arrive.
My woofer line is 5 feet 7 inches tall and the tweeter line is 5 feet 8 inches tall. My woofer line hits the one wavelength at 2,420 Hz so I get some beaming there until 4050 Hz when it starts rolling off (Linkwitz-Riley -6dB XO type) I'll also get beaming at 10KHz+ from the tweeter line but such is life.
How do they sound? Well, I don't have the crossover parts yet but 48 tweeters running a test tone at 4,200 Hz will wake up the dead! I ran the 12 five inchers "full range" to break them in and check for leaks (sealed box) After a day or two, they seemed to sound better although they have no high treble. They are loud! They don't change their sound if I'm sitting or standing and have a really "big" sound to them.
Once I get the crossover parts in, I can build the filters and test the 6 foot tall monsters out. Their life is a "garage speaker" and I want to see if the vertical line array overpowers reflections from the cement floor and metal roof.
I went with the Sony 5 inchers since they have rubber surrounds, polypropylene coated paper cones and full metal grills to protect them from garage involved flying liquids, parts etc. The boxes are "PA style" with corner edge hardware, handles in the sides and 1.5" tall rubber bumpers at the corners so not to cave in the grills when/if it falls over. Eventually, a tapped horn sub will take over at around 70Hz to get the party going.
The object of my garage speaker mess is to see if they work decently enough in the acoustic hell of a cement floor/metal roof garage. I'll stack them on top of each other floor-to-ceiling, run them in mono and play a guitar through them. Infinite line array theory anyone?
If I actually like the sound of them and would feel the need to upgrade in a few years, I'd go with 3 to 4" woofers and keep the same tweets. The Dayton Audio 3.5" full range looks like a decent driver to take the place of the cheap 5" Sonys eventually. After all, stuff a 100K speaker in a garage with a metal roof and it won't sound very good...maybe the line array will work, maybe it won't. Either way I'll have something very durable, takes up the floor space of a sheet of paper, very, very LOUD and the locals think it is the coolest speaker they've ever seen. There is something about a pair of speakers running 24 woofers and 96 tweeters that entertains people.
I'll let the world know how and if it works. One of the DIY'ers built something like it and said it sounded like a "velvet hammer". That free shipping from Parts Express takes a looooong time...
No joke, I've noticed that the most common comment when others are listening to my system is (after seeing 2 or 3 pairs of spare speakers sitting around) why don't you hook them all up?
Maybe I should work on one of these line arrays that goes floor to ceiling, with some nice 7 foot subs to go with them.
Mmm.. I've gotten that question before.
I think the thought of a line array (the idea of working each individual driver very little) is getting ahead of my budget and ability. I'd bet I could get the impressive dynamics that I'm expecting pretty easily, but doing so without huge peaks/valleys is tougher.
Something I don't understand as much as I'd like is driver placement on baffle. Lets take a simple 2-way. how far apart? centered drivers? I've been letting Jeff Bagby's BSD designer pretty much determine designs so far, but I'd like to know a bit better how woofer-tweeter interaction works.
Greg
I think the thought of a line array (the idea of working each individual driver very little) is getting ahead of my budget and ability. I'd bet I could get the impressive dynamics that I'm expecting pretty easily, but doing so without huge peaks/valleys is tougher.
Something I don't understand as much as I'd like is driver placement on baffle. Lets take a simple 2-way. how far apart? centered drivers? I've been letting Jeff Bagby's BSD designer pretty much determine designs so far, but I'd like to know a bit better how woofer-tweeter interaction works.
Greg
of hints:
The war over vertical line arrays continues
Did a lot of reading on those oddities of the audio world, the beaming/lobing issues in particular. Read about the corner loaded line arrays with all 3.5" drivers running full range and they work well with EQ. I'm sure the microphone shows a classic example of comb filtering on that puppy!
Listened to Keele's presentation on curved line arrays, researched PA line arrays VS curved arrays along with the hows and whys. Read the full report on the "Velvet Hammers" with 5" Foster woofers and the Apex Jr. tweeters crossed at 5 KHz.
In theory, all line arrays--the ones running all full ranges in particular--should sound like scrambled hash. The question I have is they don't... a microphone and a brain with ears attached process differently so I'm making sawdust to check it out.
I will NEVER build another 2-way vertical line array again! As my labor hits the triple digits in hours--I fully understand why people don't build the beasts. It has been entertaining to hear just the 5" woofers running full range, they don't sound right unless you're 2 meters back so they can "mix"? Boosted the bass +6 dB and clipped my 100 watt amp while hammering in remixed Onyx (rap/metal) and shook the floor. None of the woofers got close to their 3mm Xmax even with a clipping amp hitting the little 5 inchers with 30Hz.
These are not speakers to sit back and sip cognac out of a brandy snifter by any means. Plug a guitar into the things, set the amp to +11 and hammer the strings with a wood saw. The 96 tweeters will get hammered with clipping but 90% of the power going to them is burned off with power resistors (attached to an aluminum plate to sink heat out the back) Normal party speakers/guitar speaker/PA use is crank it till it clips then back it off a notch. Eventually it will be teamed with a tapped horn to take over the deep stuff but a dozen or two 5 inchers can take quite a beating without distorting.
Sometimes you just have to raise the pirate flag, make a ton of sawdust and build the things. Tweak it until it sounds the best and pray the metal roof don't rattle, the cement floor does not mess up the sound too bad and push the lawnmower into the nulls to improve the sound. As long as I can get decent sound in a garage, they are loud, durable and protected from flying parts, lubricants and beer foam--I'll be happy. My brandy snifter speakers are in the house--the party speaker vertical arrays complete with handles, grills, bumpers and genuine house paint "finish" sit in the garage.
Speaker beaming can be cured by a liberal application of Jim Beam
Did a lot of reading on those oddities of the audio world, the beaming/lobing issues in particular. Read about the corner loaded line arrays with all 3.5" drivers running full range and they work well with EQ. I'm sure the microphone shows a classic example of comb filtering on that puppy!
Listened to Keele's presentation on curved line arrays, researched PA line arrays VS curved arrays along with the hows and whys. Read the full report on the "Velvet Hammers" with 5" Foster woofers and the Apex Jr. tweeters crossed at 5 KHz.
In theory, all line arrays--the ones running all full ranges in particular--should sound like scrambled hash. The question I have is they don't... a microphone and a brain with ears attached process differently so I'm making sawdust to check it out.
I will NEVER build another 2-way vertical line array again! As my labor hits the triple digits in hours--I fully understand why people don't build the beasts. It has been entertaining to hear just the 5" woofers running full range, they don't sound right unless you're 2 meters back so they can "mix"? Boosted the bass +6 dB and clipped my 100 watt amp while hammering in remixed Onyx (rap/metal) and shook the floor. None of the woofers got close to their 3mm Xmax even with a clipping amp hitting the little 5 inchers with 30Hz.
These are not speakers to sit back and sip cognac out of a brandy snifter by any means. Plug a guitar into the things, set the amp to +11 and hammer the strings with a wood saw. The 96 tweeters will get hammered with clipping but 90% of the power going to them is burned off with power resistors (attached to an aluminum plate to sink heat out the back) Normal party speakers/guitar speaker/PA use is crank it till it clips then back it off a notch. Eventually it will be teamed with a tapped horn to take over the deep stuff but a dozen or two 5 inchers can take quite a beating without distorting.
Sometimes you just have to raise the pirate flag, make a ton of sawdust and build the things. Tweak it until it sounds the best and pray the metal roof don't rattle, the cement floor does not mess up the sound too bad and push the lawnmower into the nulls to improve the sound. As long as I can get decent sound in a garage, they are loud, durable and protected from flying parts, lubricants and beer foam--I'll be happy. My brandy snifter speakers are in the house--the party speaker vertical arrays complete with handles, grills, bumpers and genuine house paint "finish" sit in the garage.
Speaker beaming can be cured by a liberal application of Jim Beam
I can testify to needing lots of EQ and hearing lots of comb filtering.
About four meters away they sound great. About fifty meters away, someone is calling the cops
The box holds two 12" woofers resurrected from my junk box, in isobaric loading. Power is from a STK4191 - about 40 watts/channel and two channels. One runs the half line and the other the two woofers, line level crossover and lots of EQ to get the response in shape. Cheap and nasty, lots of fun but not very faithful so I called her 'Big Bertha'.
About four meters away they sound great. About fifty meters away, someone is calling the cops
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
The box holds two 12" woofers resurrected from my junk box, in isobaric loading. Power is from a STK4191 - about 40 watts/channel and two channels. One runs the half line and the other the two woofers, line level crossover and lots of EQ to get the response in shape. Cheap and nasty, lots of fun but not very faithful so I called her 'Big Bertha'.
I can testify to needing lots of EQ and hearing lots of comb filtering.
About four meters away they sound great. About fifty meters away, someone is calling the cops
I was thinking about full range arrays but decided on two-way to lessen the amount of EQ and comb filtering.
Reading about different types and found that; generally speaking--as long as the line is 70% or higher of the floor-to-ceiling height, it will reflect correctly. I'm going to test the effect in my house since they are at 77% of the height. Stacked on top of each other in mono, they will just fit in the garage so I can test the "infinite line" concept.
As far as your stack of full-ranges go, how does the EQ curve look? Is it a complete mess that requires 1/3rd octave and parametric bands to clean up or just a general boost for the treble and bass with a slight cut at the midrange?
I'm just trying to get an idea of what I'll need to get them decent sounding while I wait for my crossover parts.
I designed a number of the line array systems at McIntosh a few years ago (XRT24, XRT26) Also developed the first no-lobe 3 element THX arrays. Also presented an AES paper on array modeling.
People usually ask about the audibility of lobing with the multi-element arrays. I found you can hear it, specifically on pink noise and if you are fairly close to the system. It is a bit of a swish-swish-swish as you do deep knee bends in front of the system. As you get a little farther back and as you change from pink noise to music it becomes much less audible. You might notice it in the top octave of music that has a fairly continuous treble part (because your going back towards pink noise in effect). But I never found it to be distracting, or even audible for a stationary listener on music.
Some comments: If you are doing a long array, nearly floor to ceiling, then run all your units full strength in a series parallel arrangement. For mid length arrays, say 2 to 4 feet long, I would strongly recommend a level tapering scheme along the array's length, otherwise the frequency response will vary strongly with listener height. If you go shorter, then a progressive crossover scheme (tweeter in the center and additional elements coming into play as you go down the frequency range) is the way to go. In the end you want the array's effective length to grow in proportion to wavelength.
Regards,
David S.
People usually ask about the audibility of lobing with the multi-element arrays. I found you can hear it, specifically on pink noise and if you are fairly close to the system. It is a bit of a swish-swish-swish as you do deep knee bends in front of the system. As you get a little farther back and as you change from pink noise to music it becomes much less audible. You might notice it in the top octave of music that has a fairly continuous treble part (because your going back towards pink noise in effect). But I never found it to be distracting, or even audible for a stationary listener on music.
Some comments: If you are doing a long array, nearly floor to ceiling, then run all your units full strength in a series parallel arrangement. For mid length arrays, say 2 to 4 feet long, I would strongly recommend a level tapering scheme along the array's length, otherwise the frequency response will vary strongly with listener height. If you go shorter, then a progressive crossover scheme (tweeter in the center and additional elements coming into play as you go down the frequency range) is the way to go. In the end you want the array's effective length to grow in proportion to wavelength.
Regards,
David S.
I wish I had a neighbor like you. Dang!
The war over vertical line arrays continues
Did a lot of reading on those oddities of the audio world, the beaming/lobing issues in particular. Read about the corner loaded line arrays with all 3.5" drivers running full range and they work well with EQ. I'm sure the microphone shows a classic example of comb filtering on that puppy!
Listened to Keele's presentation on curved line arrays, researched PA line arrays VS curved arrays along with the hows and whys. Read the full report on the "Velvet Hammers" with 5" Foster woofers and the Apex Jr. tweeters crossed at 5 KHz.
In theory, all line arrays--the ones running all full ranges in particular--should sound like scrambled hash. The question I have is they don't... a microphone and a brain with ears attached process differently so I'm making sawdust to check it out.
I will NEVER build another 2-way vertical line array again! As my labor hits the triple digits in hours--I fully understand why people don't build the beasts. It has been entertaining to hear just the 5" woofers running full range, they don't sound right unless you're 2 meters back so they can "mix"? Boosted the bass +6 dB and clipped my 100 watt amp while hammering in remixed Onyx (rap/metal) and shook the floor. None of the woofers got close to their 3mm Xmax even with a clipping amp hitting the little 5 inchers with 30Hz.
These are not speakers to sit back and sip cognac out of a brandy snifter by any means. Plug a guitar into the things, set the amp to +11 and hammer the strings with a wood saw. The 96 tweeters will get hammered with clipping but 90% of the power going to them is burned off with power resistors (attached to an aluminum plate to sink heat out the back) Normal party speakers/guitar speaker/PA use is crank it till it clips then back it off a notch. Eventually it will be teamed with a tapped horn to take over the deep stuff but a dozen or two 5 inchers can take quite a beating without distorting.
Sometimes you just have to raise the pirate flag, make a ton of sawdust and build the things. Tweak it until it sounds the best and pray the metal roof don't rattle, the cement floor does not mess up the sound too bad and push the lawnmower into the nulls to improve the sound. As long as I can get decent sound in a garage, they are loud, durable and protected from flying parts, lubricants and beer foam--I'll be happy. My brandy snifter speakers are in the house--the party speaker vertical arrays complete with handles, grills, bumpers and genuine house paint "finish" sit in the garage.
Speaker beaming can be cured by a liberal application of Jim Beam
