hi i have some new beta 8a waiting for a project.
Unhappy about my home cinema sistem ( Cambridge audio tower , center, bookself for back + hk avr ) i m thinking to build 3 equal speakers for front.
I thinked 2 possible solution:
ribbon like fountek ( from 1500 2000 hz ) or a fullrange like dayton or fostex ( from 500 hz ) + beta 8 reflex
The problem is that i dont like how the beta 8 sound from 1500 2000 hz ( i love just for punch).
I need a solution to combine that can handle low freq and keep an high efficency ( 95 db of beta 8a ).... should i keep the beta 8 in their boxes ?
Unhappy about my home cinema sistem ( Cambridge audio tower , center, bookself for back + hk avr ) i m thinking to build 3 equal speakers for front.
I thinked 2 possible solution:
ribbon like fountek ( from 1500 2000 hz ) or a fullrange like dayton or fostex ( from 500 hz ) + beta 8 reflex
The problem is that i dont like how the beta 8 sound from 1500 2000 hz ( i love just for punch).
I need a solution to combine that can handle low freq and keep an high efficency ( 95 db of beta 8a ).... should i keep the beta 8 in their boxes ?
So what have you got so far for this design? Crossover point, filter, box size and reflex tuning?
http://www.eminence.com/speakers/speaker-detail/?model=Beta_8A
All looks pretty straightforward to me, as it goes. Not that I like your tweeter choice at all. 😀
http://www.eminence.com/speakers/speaker-detail/?model=Beta_8A
All looks pretty straightforward to me, as it goes. Not that I like your tweeter choice at all. 😀
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first of all, i have 4 of this speaker, was for my car, but i grow up 😛 and i change car and ideas about.
So why not use 3 of this for build 3 equals speakers for my living room?
Many people dont like fountek ribbons and the dispersion is a little bit poor ( in a home cinema where people are widely sitted in sofa isnt so nice ); so i was thinking about fostex fullranges: with a reflex solution they can handle 200 500 hz without any problem, they can cover a wide range without any crossover and phase problem on the speakings frequencies, they have a nice efficency.... and last they are cheap... 40 50 euro each.
I can realize a bookself solution, with 2 different chambers... i was thinking to use also concrete and made a millled form ... and high tickness wood...
just many ideas... but i need tips 🙂
some throubles in my mind: different power size ( 8a can handle more than 200 w ), different style of sound....
p.s. sorry for my english
So why not use 3 of this for build 3 equals speakers for my living room?
Many people dont like fountek ribbons and the dispersion is a little bit poor ( in a home cinema where people are widely sitted in sofa isnt so nice ); so i was thinking about fostex fullranges: with a reflex solution they can handle 200 500 hz without any problem, they can cover a wide range without any crossover and phase problem on the speakings frequencies, they have a nice efficency.... and last they are cheap... 40 50 euro each.
I can realize a bookself solution, with 2 different chambers... i was thinking to use also concrete and made a millled form ... and high tickness wood...
just many ideas... but i need tips 🙂
some throubles in my mind: different power size ( 8a can handle more than 200 w ), different style of sound....
p.s. sorry for my english
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What are you unhappy about with your current speakers? The Beta 8 are a PA driver and hence require a big box and don't get down that low. But they will go loud. So if more bass is what you are after they are not the right choice.
the problems of my actual setups are mostly in the center: same series of tower but smaller in liters and in speakers size, poor bass definition, voices are not so defined.
Towers have the same problem of mid high ( same tweeters ) but low resp are ok, just ... undefined and confused. Globally the system definition is... low, the speakings are confused, the audio scene is not so clear and fresh, present... seem somewhere far behind a cover.... I dont need a very low freq from my center ( i have sub also ), but i need more a defined and fresh audio scene expecially with low volume...
Towers have the same problem of mid high ( same tweeters ) but low resp are ok, just ... undefined and confused. Globally the system definition is... low, the speakings are confused, the audio scene is not so clear and fresh, present... seem somewhere far behind a cover.... I dont need a very low freq from my center ( i have sub also ), but i need more a defined and fresh audio scene expecially with low volume...
I really don't have time to design a FAST speaker from scratch. 😀
But all is not lost with something more conventional. I knew I'd seen an Eminence Beta 8A in a commercial design. Tekton Design M-Lore:
Tekton Design Lore-M
Tekton Design M-Lore Loudspeaker Reviewed
An earlier version with a similar Eminence Alpha 8A below. It's enough to know it works well. The rest, as they say, is just technique. 😎
But all is not lost with something more conventional. I knew I'd seen an Eminence Beta 8A in a commercial design. Tekton Design M-Lore:
Tekton Design Lore-M
Tekton Design M-Lore Loudspeaker Reviewed
An earlier version with a similar Eminence Alpha 8A below. It's enough to know it works well. The rest, as they say, is just technique. 😎
Attachments
i thinked also a tweeter array like 2 XT25SC-90/04 VIFA 1 INCH TWEETER and do a more conventional solution
That's not conventional at all. Aren't you going to take the impedance rather low? 😀
It's actually not easy to do this. It's going to need a loud tweeter.
TQWT-
First, take a look at this home-theater oriented design using the Beta 8a:
Fusion-8 Alchemy - Fusion Series - Waveguide Speaker Kits DIY Sound Group
19 liter reflex cabinet, good to 70 Hz or so (you'll want a sub or three), high efficiency horn tweeter crossed at 2500 Hz. Since you already have the Betas, you would have to see if Erich would provide just the waveguide, compression driver and crossover. The box design is available from the site.
The crossover point is higher than you would like, but it was done by a very respected designer, and I'm sure was chosen to help match the directivity of the tweeter to that of the Beta in the crossover range. The speaker has been very well received.
Or, you do as I did and could choose a different compression driver and waveguide and do it yourself. I'm using the Beta's with a Faital Pro HF100 / STH100 top end, and bi-amping with a MiniDSP. I designed a small MLTL enclosure using Martin King's worksheets (internal dimensions 8.5 in wide x 7.5 in deep x 30 in tall, 3" dia x 3" long port located 8" from the bottom, driver as high as possible in the box, horn sitting on top). The bass is pretty good to 60 Hz or so, I filter below 50 in the MiniDSP. Still playing with crossover configurations. If you need a passive crossover, I'm NOT the guy to turn to for help!
I'm fairly pleased so far, but I'm a novice at x-over design and a long way from done. At some point I'll upgrade to a MiniDSP 2 x 8 (or 4 x 10) and add some woofers to take over the bottom end, leaving the beta working from maybe 150 to 2000.
Bill
Fusion-8 Alchemy - Fusion Series - Waveguide Speaker Kits DIY Sound Group
19 liter reflex cabinet, good to 70 Hz or so (you'll want a sub or three), high efficiency horn tweeter crossed at 2500 Hz. Since you already have the Betas, you would have to see if Erich would provide just the waveguide, compression driver and crossover. The box design is available from the site.
The crossover point is higher than you would like, but it was done by a very respected designer, and I'm sure was chosen to help match the directivity of the tweeter to that of the Beta in the crossover range. The speaker has been very well received.
Or, you do as I did and could choose a different compression driver and waveguide and do it yourself. I'm using the Beta's with a Faital Pro HF100 / STH100 top end, and bi-amping with a MiniDSP. I designed a small MLTL enclosure using Martin King's worksheets (internal dimensions 8.5 in wide x 7.5 in deep x 30 in tall, 3" dia x 3" long port located 8" from the bottom, driver as high as possible in the box, horn sitting on top). The bass is pretty good to 60 Hz or so, I filter below 50 in the MiniDSP. Still playing with crossover configurations. If you need a passive crossover, I'm NOT the guy to turn to for help!
I'm fairly pleased so far, but I'm a novice at x-over design and a long way from done. At some point I'll upgrade to a MiniDSP 2 x 8 (or 4 x 10) and add some woofers to take over the bottom end, leaving the beta working from maybe 150 to 2000.
Bill
That's very interesting, Bill. Jeff Bagby is a good designer and an occasional visitor here. But my sort of diyaudio is not really about building kits. What do you learn from that?
I wouldn't say his crossover is low at all though. With a more conventional tweeter, this whole thing is actually going to be easier with a higher 3.5kHz crossover point IMO.
The 20L reflex box is what I would expect from the Eminence data. These high efficiency speakers inevitably sacrifice bass extension, but in Europe we don't have living rooms the size of aircraft hangers, so not an issue really.
But I'm waiting for Mordor to come up with some filter and tweeter ideas. It's his idea and he's taking on the work and inevitable tweaking. FWIW, there are two filter approaches that I can see. Second order and third order. The high efficiency Troels TQWT- approach may be hard to implement with a regular sort of tweeter, which adds an interesting element of trial and error.
The Eminence Beta 8A is a mere 0.49 Le inductance and has quite a nice natural frequency response, so should sound good on small filter values. It's really the high tweeter efficiency requirement that is hardest here. 🙂
I wouldn't say his crossover is low at all though. With a more conventional tweeter, this whole thing is actually going to be easier with a higher 3.5kHz crossover point IMO.
The 20L reflex box is what I would expect from the Eminence data. These high efficiency speakers inevitably sacrifice bass extension, but in Europe we don't have living rooms the size of aircraft hangers, so not an issue really.
But I'm waiting for Mordor to come up with some filter and tweeter ideas. It's his idea and he's taking on the work and inevitable tweaking. FWIW, there are two filter approaches that I can see. Second order and third order. The high efficiency Troels TQWT- approach may be hard to implement with a regular sort of tweeter, which adds an interesting element of trial and error.
The Eminence Beta 8A is a mere 0.49 Le inductance and has quite a nice natural frequency response, so should sound good on small filter values. It's really the high tweeter efficiency requirement that is hardest here. 🙂
at the end seem that neocd35h could be some of the best solutions for this project in terms of efficiency, fastness and simplicity😱
this is also better in terms of bandwith and dispersion: http://www.europe-audio.com/document.asp?document_id=2408&link=datasheets\fountek\neocd3.pdf
but how will sound... ? how the low dispersion will influence the result
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I have no idea how they will sound. Troels reckoned they didn't integrate well:
TQWT-
Definite maybe though. You can filter the eminence bass to either 2.5 or 3.5 Khz crossover for sure. Whatever suits. I think you can do a tiny bit with level too. Maybe 2-3dB quieter with heavier bass coils. 🙂
Troels mentioned the JBL LE26 cone tweeter worked well in a waveguide. I don't know its efficiency, but the Monacor HT22/8 and the Visaton TW70 are both quite loud. 89 and 90dB 1W/1m respectively. Good sounding units. I use them both.
I wonder if these are fittable in a Monacor WG300 waveguide: 7100-waveguide
I suppose we'd have to know how loud a JBL LE26 is. That was easy. Looks like about 94dB:
JBL LE26 tweeter-
TQWT-
Definite maybe though. You can filter the eminence bass to either 2.5 or 3.5 Khz crossover for sure. Whatever suits. I think you can do a tiny bit with level too. Maybe 2-3dB quieter with heavier bass coils. 🙂
Troels mentioned the JBL LE26 cone tweeter worked well in a waveguide. I don't know its efficiency, but the Monacor HT22/8 and the Visaton TW70 are both quite loud. 89 and 90dB 1W/1m respectively. Good sounding units. I use them both.
I wonder if these are fittable in a Monacor WG300 waveguide: 7100-waveguide
I suppose we'd have to know how loud a JBL LE26 is. That was easy. Looks like about 94dB:
JBL LE26 tweeter-
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S7,
I cited JB's design as an example of a how the Beta has been used and (by reputation) used well. You'll notice that I didn't buy the kit, precisely for the experience of trying working it out for myself.
You need a high-efficiency tweeter? Compression drivers have that covered!
Bill
It was a good link, Bill. Thanks. I know exactly what Jeff did there with the 2.5kHz filter and the horn driver, but we must respect his copyright, eh? 🙂
So yes, that is one approach if the horn driver or similar is easily available in Italy.
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