Let's wake up Adason, shall we?
I'll throw my questions at you as well, OK?
In your concept drawings the curve was 45*, did you cut them at that? Why not 36* like Keele's?
Do you notice any vertical lobing with the tweeters? in that they do not go full length?
ie; is there a noticable difference when sitting near field or standing near field?
Thanks,
Ron
I'll throw my questions at you as well, OK?
In your concept drawings the curve was 45*, did you cut them at that? Why not 36* like Keele's?
Do you notice any vertical lobing with the tweeters? in that they do not go full length?
ie; is there a noticable difference when sitting near field or standing near field?
Thanks,
Ron
Ron, when it comes to dimensions, I followed them literally.
I am not sure what you mean curve was 45*, Keele's was 36*...
What is "*" for, degrees?
When it comes to the tweeter array, I have not finished them all the way to the floor or all the way to the top, since I do not listen laying on the floor or all the way up in the ceiling. I listen either sitting in the chair or walking around. At those levels, vertical lobing is nonexistent. It measures horizontally and vertically flat at listening height as its supposed to.
I am not sure what you mean curve was 45*, Keele's was 36*...
What is "*" for, degrees?
When it comes to the tweeter array, I have not finished them all the way to the floor or all the way to the top, since I do not listen laying on the floor or all the way up in the ceiling. I listen either sitting in the chair or walking around. At those levels, vertical lobing is nonexistent. It measures horizontally and vertically flat at listening height as its supposed to.
I still like the ns3 from aura. They sound great on their own, and even better in curved array. There are members in the forum which will claim that cheap drivers will only lead to bad sound. Something like "crappy speakers in array will lead to even crappier sound" ... or some bs like that (at the end he puts rather big fullrange in straight array consisting of expensive drivers...blah).
First of all, Ns3 do sound good, even they are cheap. I pretested them before deciding to buy 50, I put 4 of them in parallel, in small cardboard box, which gives 4 ohm, and listening to four per side gave me confidence they will sound good in array. They easily cover 160Hz to 10kHz, which is impressive for midrange, as they are used only.
CBT as I built them only consist of one capacitor for tweeters, otherwise they are biamped. The better electronics I throw at them, the better they sound, convincing me there is no limit how well they will sound. I am experimenting a lot with active crossovers, which are pretty critical for sound quality. Completely hate OPA based junk, either commercial, or self made. Have not decided to go digital yet, but it maybe the future.
Its time you guys start building something, not just speculating...
Damn Adason, you always make me laugh. "
Its time you guys start building something, not just speculating... ".
Yes, the "*" designation was for degrees. The CAD drawing you posted was for 45*, hence my question. I guess you built them at 36*. They look like 36* in the photos.
// is used as parallel.
I've bought 80 of the little Aura NS3 and almost 100 tweeters.
Priced out Baltic Birch 60" x 60" at $55 3/4" sheet. Not a bad price for first class building materials.
I've got Zero data (T/S parameters) on the tweeters, bought them from Zero Cool here on the forums, he has no data on these when he bought them.
I'm going to have to either build the XO by ear or buy some type of measuring device / software to measure the drivers. I'm cheap!
I've been looking for data to determine what the cabinet depth should be. I'm going to just take a guess at 7", as they look square when viewed on end. The VAS of the driver suggests a 1 liter sealed cabinet per driver. Mounting them as close as possible C-C, does not allow for a separate chamber per driver/group of drivers. So 7"x7" should be close enough.
I want to build a center channel also with the same drivers and tweeters, which is why I was asking about the vertical lobing & not having the tweeters go full cabinet length. I won't have enough tweeters to build my center channel if I install the tweeters full cabinet length in the L&R Speakers. So I'm thinking 32 tweeters each, which leaves me some left over for future replacement if needed.
Question about impedances, (Home Theater only application)
I'm going to be powering these with a Pioneer vsx60 elite, is it easier on the Receiver's amps to group the drivers in higher or lower Ohms? Amp is rated 6-16 Ohms.
ie:
1) 6 drivers in // =2.66 Ohms ---> 3 groups of 6 drivers in Series =7.98 Ohms
Q. Does that 2.66 Ohm (per group) present a difficult load? or does the Amp only see the total load once the 3 groups are in series which adds to 7.98 Ohms?
Q. How does the 2.66 Ohms of the group effect the driver SPL?
2) Would it be better to simply // two drivers to present an 8 Ohm load, then figure out the series , // arrangement in the cabinet and try to obtain a 6-16 Ohm total load?
Sorry about the "Dumb" questions, I've read many articles and I'm almost there, but perhaps it's just hands-on experience I'm lacking in understanding the Ohms / drivers in series and // relationships.
I'm having a hard time wrapping my head around this for some reason.
It's hard to know what you don't know, if you know what I mean....
Thanks for the help.
Ron
Its time you guys start building something, not just speculating... ".
Yes, the "*" designation was for degrees. The CAD drawing you posted was for 45*, hence my question. I guess you built them at 36*. They look like 36* in the photos.
// is used as parallel.
I've bought 80 of the little Aura NS3 and almost 100 tweeters.
Priced out Baltic Birch 60" x 60" at $55 3/4" sheet. Not a bad price for first class building materials.
I've got Zero data (T/S parameters) on the tweeters, bought them from Zero Cool here on the forums, he has no data on these when he bought them.
I'm going to have to either build the XO by ear or buy some type of measuring device / software to measure the drivers.
I'm cheap!I've been looking for data to determine what the cabinet depth should be. I'm going to just take a guess at 7", as they look square when viewed on end. The VAS of the driver suggests a 1 liter sealed cabinet per driver. Mounting them as close as possible C-C, does not allow for a separate chamber per driver/group of drivers. So 7"x7" should be close enough.
I want to build a center channel also with the same drivers and tweeters, which is why I was asking about the vertical lobing & not having the tweeters go full cabinet length. I won't have enough tweeters to build my center channel if I install the tweeters full cabinet length in the L&R Speakers. So I'm thinking 32 tweeters each, which leaves me some left over for future replacement if needed.
Question about impedances, (Home Theater only application)
I'm going to be powering these with a Pioneer vsx60 elite, is it easier on the Receiver's amps to group the drivers in higher or lower Ohms? Amp is rated 6-16 Ohms.
ie:
1) 6 drivers in // =2.66 Ohms ---> 3 groups of 6 drivers in Series =7.98 Ohms
Q. Does that 2.66 Ohm (per group) present a difficult load? or does the Amp only see the total load once the 3 groups are in series which adds to 7.98 Ohms?
Q. How does the 2.66 Ohms of the group effect the driver SPL?
2) Would it be better to simply // two drivers to present an 8 Ohm load, then figure out the series , // arrangement in the cabinet and try to obtain a 6-16 Ohm total load?
Sorry about the "Dumb" questions, I've read many articles and I'm almost there, but perhaps it's just hands-on experience I'm lacking in understanding the Ohms / drivers in series and // relationships.
I'm having a hard time wrapping my head around this for some reason.
It's hard to know what you don't know, if you know what I mean....
Thanks for the help.
Ron
Yes, I am curious too.
Especially about the sound stage.
With the array of tweeters from the bottom to about the middle, is the
soundstage from center to low, especially when standing up?
For rogozhin, should he ever read this, J arrays are generally flown high above
the audience, and are likely not applicable to most home systems.
_-_-
Especially about the sound stage.
With the array of tweeters from the bottom to about the middle, is the
soundstage from center to low, especially when standing up?
For rogozhin, should he ever read this, J arrays are generally flown high above
the audience, and are likely not applicable to most home systems.
_-_-
Awwww, Damn it.
There's a bear in the house now.....,
Thanks Very much Adason, I think I now understand what questions to ask! I really, really appreciate you taking the time to answer.
I have found further reading(s) about line arrays with respect to CBTs . One of the papers I read said that it WAS possible to implement the XOs passively, and active multiple amps was not necessary, However preferred. This has been my goal from the start. Less complexity in the HT is good. My other system is so complex that the Wife unit cannot use it.....shhhh, (kind of a good thing).
Next item to consider is incorporating the tweeter section into the impedance mix. Tweeters are 8 Ohms. All other specs. are unknown.
Question: This is about CBT style speakers. Not straight arrays.
If the tweeter array starts at the floor level, and is 2/3 the line length, will the floor reflection only add SPL near the floor/seated positions? I would GUESS so. As my design will be used for Home Theater only, standing height listening is of low importance.
Same question as Bear, just asked differently.
Please comment on my thoughts.
Ron
There's a bear in the house now.....,
Thanks Very much Adason, I think I now understand what questions to ask! I really, really appreciate you taking the time to answer.
I have found further reading(s) about line arrays with respect to CBTs . One of the papers I read said that it WAS possible to implement the XOs passively, and active multiple amps was not necessary, However preferred. This has been my goal from the start. Less complexity in the HT is good. My other system is so complex that the Wife unit cannot use it.....shhhh, (kind of a good thing).
Next item to consider is incorporating the tweeter section into the impedance mix. Tweeters are 8 Ohms. All other specs. are unknown.
Question: This is about CBT style speakers. Not straight arrays.
If the tweeter array starts at the floor level, and is 2/3 the line length, will the floor reflection only add SPL near the floor/seated positions? I would GUESS so. As my design will be used for Home Theater only, standing height listening is of low importance.
Same question as Bear, just asked differently.
Please comment on my thoughts.
Ron
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Roger Russel, formerly of McIntosh, makes what appears to be an excellent line array (I haven't actually heard it). He makes the point that shading is no good because you end up trying to get most of the sound out of a smaller quantity of drivers, each of which are 3 inch... But also, the great thing about a line array should be how it works with the acoustics of the typical listening room. Russel's may be the only one that does this right (in my opinion). Google his name and read what he has to say about this.
Others with their variations such as curved enclosures and shading may just be shooting in the dark - not seeing the bigger picture. How a speaker interacts with room acoustics is much more important than winning the phase game for example, which is impossible anyway unless you are in an anechoic chamber, with your head in exactly the right place. Even then it's not perfect, and you've still got inter-aural crosstalk.
If I can sell my OB's, I may well build what Russel has (since I can't afford the $19,000 or so he charges, plus shipping). The Peerless TG9FD10-08 3 inch he uses is available at Madisound (virtually identical) for $22 per (minus 10%+ discount on these quantities). It has perhaps the most correctable frequency response of any 3 inch driver I know of, usable from 30HZ to 16kHZ, and less cavity effect from too much surround suspension protrusion relative to many other drivers (Dayton for ex.), well vented flat spider and pole piece, has the shorting ring on the pole piece, rubber surrounds (you DO NOT want foam surrounds, they will deteriorate badly over time)... The only potential drawback with this driver is that Peerless production has move to China about 2 years ago (according to Madisound), so I'd order 2 first, and verify that the new facility is doing them right, before ordering 50ish. Separate tweeters will blur imaging unless the xover is above 6kHZ. Any EQ done passively will subtract from system efficiency a LOT, do it actively ahead of poweramps.
Others with their variations such as curved enclosures and shading may just be shooting in the dark - not seeing the bigger picture. How a speaker interacts with room acoustics is much more important than winning the phase game for example, which is impossible anyway unless you are in an anechoic chamber, with your head in exactly the right place. Even then it's not perfect, and you've still got inter-aural crosstalk.
If I can sell my OB's, I may well build what Russel has (since I can't afford the $19,000 or so he charges, plus shipping). The Peerless TG9FD10-08 3 inch he uses is available at Madisound (virtually identical) for $22 per (minus 10%+ discount on these quantities). It has perhaps the most correctable frequency response of any 3 inch driver I know of, usable from 30HZ to 16kHZ, and less cavity effect from too much surround suspension protrusion relative to many other drivers (Dayton for ex.), well vented flat spider and pole piece, has the shorting ring on the pole piece, rubber surrounds (you DO NOT want foam surrounds, they will deteriorate badly over time)... The only potential drawback with this driver is that Peerless production has move to China about 2 years ago (according to Madisound), so I'd order 2 first, and verify that the new facility is doing them right, before ordering 50ish. Separate tweeters will blur imaging unless the xover is above 6kHZ. Any EQ done passively will subtract from system efficiency a LOT, do it actively ahead of poweramps.
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very good point about the shading, I share the same opinion, plus I am lazy, wireing all mids same is lot easier...I think I commented on this before
however, I prefer tweeters there, since they are smaller than midranges, and tighter together
and I use CBT with the sub (actualy two subs..), I have not heard Rogers array, but I read numerous times how during demonstration his array (or perhaps the equalizer) clipped and sounded like drivers were bottoming out, so the demonstration was a failure
you can't seriously expect great bass out of 3" fullrange Bob...
however, I prefer tweeters there, since they are smaller than midranges, and tighter together
and I use CBT with the sub (actualy two subs..), I have not heard Rogers array, but I read numerous times how during demonstration his array (or perhaps the equalizer) clipped and sounded like drivers were bottoming out, so the demonstration was a failure
you can't seriously expect great bass out of 3" fullrange Bob...
I wonder why he uses the TG9FD (fiber glass cone) rather than the TC9FD (paper cone) which has a higher frequency response to 20 kHz, handles more power, and is less expensive ($12 ea)? The equalization to the IDS25 is the key and to get 30 Hz out of the little Vifa is going to take a lot of stroke. I have always wanted to build a copy of this array.
Without shading network, the speaker is quite similar to a straight line array. Exhibiting rapid variation and undulation of sound pressure with position and lobing.
Shading is much more important then curving. Curving is used to avoid beaming. I think it's unfair to call this speaker a Keele line array. They are vastly different in regards to the polar response.
Shading is much more important then curving. Curving is used to avoid beaming. I think it's unfair to call this speaker a Keele line array. They are vastly different in regards to the polar response.
The TG9FD has a more correctable high end response, and the glass fiber cone material is allegedly better somehow (resolution?). Yes, Roger Russel has about 20dB of boost peaking at about 30HZ, relative to 200HZ, and a slight lift at the very high end. He published a "how to build" article on it back in about 2005 where he shows the EQ graph.
I thought I unswered that already...let me draw a picture so we are absolutely clear here
I have noe intention of being rude, but what I wrote is the fact. It's well documented.
I don't see a big problem of a title being off, but it's ok for people to know that this isn't a Keele CBT design. I'll leave at that. The papers are out there for people to read and find out for themselves.
Hi Bear, here is a little picture a draw to demonstrate where is good coverage by tweeters. You said they go only to the half of an array, no they go to 2/3rds. There is 16 midranges and tweeters go to ~mid No 10. Picture better 1000 words.
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