I’m very much enjoying a simple box with a pair of the MA SOTA drivers but now I’m looking to downsize my main system and the Tysen/FAST system piqued my interest.
The Alpair 5.3 looks like a little detail monster so that is my choice for the mid/high portion
For the bass I’ve always liked the look of the SB15SFCR39-8 from SB Acoustics (https://doc.soundimports.nl/pdf/brands/SB Acoustics/SB15SFCR39-8/SB15SFCR39-8.pdf) A pair in an opposed side firing,push push design but sealed. This might be nice as they have a lovely deep roll off for tuneful lows In a sealed box.
Am I nuts for going sealed? Will the Alpair 5.3 keep up? What sort of positioning in the room should a Tysen have with its side firing woofers? I’m used to much larger speakers 15/10/1.4CD inch drivers, but have lost WAF. I know the A5.3 is renowned for detail so I’m wondering what sort of picture will this design can paint?
Any thoughts would be greatly received.
The Alpair 5.3 looks like a little detail monster so that is my choice for the mid/high portion
For the bass I’ve always liked the look of the SB15SFCR39-8 from SB Acoustics (https://doc.soundimports.nl/pdf/brands/SB Acoustics/SB15SFCR39-8/SB15SFCR39-8.pdf) A pair in an opposed side firing,push push design but sealed. This might be nice as they have a lovely deep roll off for tuneful lows In a sealed box.
Am I nuts for going sealed? Will the Alpair 5.3 keep up? What sort of positioning in the room should a Tysen have with its side firing woofers? I’m used to much larger speakers 15/10/1.4CD inch drivers, but have lost WAF. I know the A5.3 is renowned for detail so I’m wondering what sort of picture will this design can paint?
Any thoughts would be greatly received.
Attachments
A5.2/3, or a MAOP 5.3 is an excellent choice for midTweeter and is next for Tysen (if it makes V3).
Crossing below the baffle-step of the side mounted woofers means that they are operating omnidirectional (4π radiation) and as such it makes little difference what direction they fire.
I like sealed, what we used in Ellipsa (by do i miss SDX7), but a driver that works well sealed is hard to find, i will have a look at the SB. Sealed allows for EQing as low as the power you have and the excusion limits are not pushed too hard.
Disucussion of the LS60 has, finally, really slammed home the advantages of push-push and the sensibility of mountint them on the side. Monitor Audio has also taken the same idea and turned it inside out. Both the KEF & the MA have custom designed woofers for the application.
https://hometheaterreview.com/monitor-audio-concept-50-made-sound-waves-at-munich-2022/
Note that active makes for much easier XO, a passive, as always, is the harder task, getting something like a miniDSP just to sort out the direction to go with a passive or even an active analog XO.
dave
Crossing below the baffle-step of the side mounted woofers means that they are operating omnidirectional (4π radiation) and as such it makes little difference what direction they fire.
I like sealed, what we used in Ellipsa (by do i miss SDX7), but a driver that works well sealed is hard to find, i will have a look at the SB. Sealed allows for EQing as low as the power you have and the excusion limits are not pushed too hard.
Disucussion of the LS60 has, finally, really slammed home the advantages of push-push and the sensibility of mountint them on the side. Monitor Audio has also taken the same idea and turned it inside out. Both the KEF & the MA have custom designed woofers for the application.
https://hometheaterreview.com/monitor-audio-concept-50-made-sound-waves-at-munich-2022/
Note that active makes for much easier XO, a passive, as always, is the harder task, getting something like a miniDSP just to sort out the direction to go with a passive or even an active analog XO.
dave
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I’ve already seen several excellent in depth reviews of the LS60, and aside from the obvious issues of long term serviceability that has long plagued the active subwoofer niche, it certainly looks very interesting indeed, but doesn’t seem to leave a lot of room for a DIYer to fiddle with - except for maybe magic power cords😵
As I’ve been un-moved by far more expensive passive speakers by several well known high end UK builders - even for that matter an earlier pair of passive LS50 UniQ - I’d love to hear a pair of these. As many of us have experienced, and professional reviewers have been relating since well before YouTube, there can be synergy between certain combinations of amplifiers and speaker systems / drivers.
As I’ve been un-moved by far more expensive passive speakers by several well known high end UK builders - even for that matter an earlier pair of passive LS50 UniQ - I’d love to hear a pair of these. As many of us have experienced, and professional reviewers have been relating since well before YouTube, there can be synergy between certain combinations of amplifiers and speaker systems / drivers.
There are other steps. Equalising the existing speaker is something that is often overlooked, some assume it should just work in their room.. some speakers are just not EQed properly to begin with. Some are EQed to deal with acoustic shortcomings that need better attention.
taking queues from the LS60 brings up some technical questions
The SB15SFCR39-8 is 84.7mm from the back of the faceplate to the back of the magnet. Happily they are not vented and can be butted up magnet to magnet. I like to use 12 or 15mm ply (sometimes they come in at the same price 😲) and heavy bracing. So 84.7x2=169.4mm minimum cabinet width, minus 24mm ply leaves an internal width of 145.4mm. The Alpair 5.3 faceplate is 100mm in diameter and the minimum box width to accommodate the SB15SFCR39-8 is roughly 170mm. So I’ll have 70/2=35mm either side of the faceplate to play with.
1. Does magnet to magnet cause any issues?
2. Is 145mm internal width going to cause any sound reflection issues, or other audible issues?
3. Do I have to produce a heavy roundover on the front panel for best integration?
The SB15SFCR39-8 is 84.7mm from the back of the faceplate to the back of the magnet. Happily they are not vented and can be butted up magnet to magnet. I like to use 12 or 15mm ply (sometimes they come in at the same price 😲) and heavy bracing. So 84.7x2=169.4mm minimum cabinet width, minus 24mm ply leaves an internal width of 145.4mm. The Alpair 5.3 faceplate is 100mm in diameter and the minimum box width to accommodate the SB15SFCR39-8 is roughly 170mm. So I’ll have 70/2=35mm either side of the faceplate to play with.
1. Does magnet to magnet cause any issues?
2. Is 145mm internal width going to cause any sound reflection issues, or other audible issues?
3. Do I have to produce a heavy roundover on the front panel for best integration?
We have always put something between, and could adjust the brace to get the perfect fit. It will take more precison since you will not have that option.
dave
The woofer mounts from one side, one driver pressed into place… at least that is what i understood from the white paper.
dave
dave
Mounted in a 300mm deep cabinet an online calculator gives the baffle step frequency as 386Hz. So crossing at 300-350Hz would make the woofer output omnidirectional. Does that figure look correct? Also will the Alpair 5.3 be able to keep up
crossed above that frequency?
As to the SB15SFCR39-8, all I can offer is that it’s rated at 10mm ‘linear coil travel point to point’ is 10mm. I guess this is SB speak for Xmax?
Thanks for all the other input on the LS60. The dual concentric voicecoils of the woofers is a stroke of genius and gives the daintier cabinet width.
Are there any more thoughts on the questions in post #5?
Yes the lack of xmax detail is weird. I’m not too clever with design specifics. Other than the max oddity, can anyone see a problem running the SB oval sealed in this design? Before I order that is 😁
Just found out that SBA make a 4ohm version as well. Which is preferable, 2x8ohm drivers wired as 4ohm, or 2x4ohm drivers wired as 8ohm? I have about 6 amps to play with if that helps
Passive XO? You want the sensitivity of the woofers 2-4dB more sensitive than the midTweeter.
If that does not decide you, then look to the amp you are using, then parallel makes more sense if it doesn’t care.
In Tysen we used 2 x 4Ω in series, un the big MTM we used 2 x 8Ω in parallel.
dave
If that does not decide you, then look to the amp you are using, then parallel makes more sense if it doesn’t care.
In Tysen we used 2 x 4Ω in series, un the big MTM we used 2 x 8Ω in parallel.
dave
I know that having very shallow speaker cabinets is not advised. Will having a narrow cabinet of say 150mm internally cause issued for the mid/woofers or sound?
I can widen it to 170mm internally at the cost of the somewhat 'sexier' narrow baffle but sound should trump visuals.
I can widen it to 170mm internally at the cost of the somewhat 'sexier' narrow baffle but sound should trump visuals.
Thanks Dave. Are there any sort of guidelines on depth issues?
I've found some great aluminium profile with a 40mm radius that'll take care of the wider baffle looks so a 175mm internal width leaving 30mm between magnets. I had a thought about adding something to the magnets to spread the rearward output of the woofers. Imagine a cone like they put on your dog after the vets! One on each magnet where it meets the basket should scatter the rearward wave quite well. What do you think?
I've found some great aluminium profile with a 40mm radius that'll take care of the wider baffle looks so a 175mm internal width leaving 30mm between magnets. I had a thought about adding something to the magnets to spread the rearward output of the woofers. Imagine a cone like they put on your dog after the vets! One on each magnet where it meets the basket should scatter the rearward wave quite well. What do you think?
Sorta of. With the hornish PAWOs, the addition of a 20mm supraBaffle largely fixed the issue.
In Ellipsa, we had no issues.
There is possiby an issue with The Hawking Memorial Obelissk. The Jordans have gone, i need someone to takeon the project of adding an sB. Free cabinets, you supply A10.3/p/11ms. You have to come get them.
http://wodendesign.com/downloads/HawkingMemorialObelisk-0v81-090418.pdf
dave
In Ellipsa, we had no issues.
There is possiby an issue with The Hawking Memorial Obelissk. The Jordans have gone, i need someone to takeon the project of adding an sB. Free cabinets, you supply A10.3/p/11ms. You have to come get them.
http://wodendesign.com/downloads/HawkingMemorialObelisk-0v81-090418.pdf
dave