I am going to experiment with Mundorf Angel Hair that I have left over from a previous project, https://www.mundorf.com/audio/en/shop/Damping/MSilence_Angel/
but Mundorf seems to recommend their "Unicorn Tail" variant for lower frequency damping and transmission lines. Not sure which will perform better or if it's needed at all, guess that's why it will be an experiment..
I have not tried that. For damping purposes i usually use cotton felt and acoustic-stuff Scott recommends at least hollow dacron. Zia had the opportunity to they many varieties and there are decided differences in performance.
Onley used felt in his labyrinth, looks to be about 2”. Bailey brought long haired sheep's wool to the table. It works but, moths like it, it sags (mix 50/50 with man-made fluff), IMF/TDL/PMC champion foam (very consistent, i am not convinced it is very effective), and since then much has been tried.
I have samples of two of the more exotic euro fills, both seem to be very very fine fibreglass. Not enuff to do much with.
Many builds do not tease the pluff sufficiently. Acoustastuff is particularly tangled and takes a looonnnggg time.
https://www.madisoundspeakerstore.com/acoustic-damping/dampers-acousta-stuf/lb/
Seems the supply chain issues have pushed its price up (but less than half the price of PE). I have a tote at old prices but shipping to EU? I couldn’t find an EU source.
Because of vagaries in what is available where, the actual spec for the box is somewhat generic, rooms differ, amps differ, tastes differ so it is impossible to narrow things down any further.
I applaud Yves for his experiments. And the ones before, as well as those to come. Sharing knowledge empowers al of us and pushes the art forward.
And by my recent email he has set a new project into action. Still haven’t seen what Scott has coming. Should be interesting, i get the feeling that Scott had to stretch his already vast knowledge a bit further for what is coming ;^)
dave
Onley used felt in his labyrinth, looks to be about 2”. Bailey brought long haired sheep's wool to the table. It works but, moths like it, it sags (mix 50/50 with man-made fluff), IMF/TDL/PMC champion foam (very consistent, i am not convinced it is very effective), and since then much has been tried.
I have samples of two of the more exotic euro fills, both seem to be very very fine fibreglass. Not enuff to do much with.
Many builds do not tease the pluff sufficiently. Acoustastuff is particularly tangled and takes a looonnnggg time.
https://www.madisoundspeakerstore.com/acoustic-damping/dampers-acousta-stuf/lb/
Seems the supply chain issues have pushed its price up (but less than half the price of PE). I have a tote at old prices but shipping to EU? I couldn’t find an EU source.
Because of vagaries in what is available where, the actual spec for the box is somewhat generic, rooms differ, amps differ, tastes differ so it is impossible to narrow things down any further.
I applaud Yves for his experiments. And the ones before, as well as those to come. Sharing knowledge empowers al of us and pushes the art forward.
And by my recent email he has set a new project into action. Still haven’t seen what Scott has coming. Should be interesting, i get the feeling that Scott had to stretch his already vast knowledge a bit further for what is coming ;^)
dave
Ignore the Bradbury stuff there are some charts at the bottom that compare the effectiveness of various damping materials, you can see they all fall off at the bottom, but one that falls off less should be of benefit in a TL/Voigt/Horn
https://www.t-linespeakers.org/projects/tlB/appendix/bradbury/index.html
The data is 2 decades old.
dave
I think that is one of the exotica smples i have. I don’t think it had Mndorf attached to it at teh time i got it.
dave
"What is coming"... Come now.. I haven't finished my SIlbury's yet..
I gasp to think about going back to my sheet-goods supplier for more plywood.. I paid more than $140 a sheet for 9mm meranti & it would be easier to find magical pixies than 18mm BB in the north-east of the US at the moment. Guess thats a good excuse to experiment with open-baffles "enclosures"..Thanks, so as liner/damper for the surface of the area behind the speaker we can use 1/2" (12 mm) F-15 SAE Wool Felt, with a low density of around 2,3 kg/m2, like this one: https://cdn.shopify.com/s/files/1/0810/3769/products/F15N_1-2_2048x.jpg ( https://www.aetnafelt.com/collectio...-industrial-sae-wool-felt-by-the-yard-72-wide )
And for the Silbury that's it. For the FHXL it is needed also to stuff the internal part of the speaker and for that it is needed cotton/wool felt like this one: https://www.planet10-hifi.com/images/40g-acousta-stuff.jpg teased/carded for hours to align the fibers and occupy alot of volume.
Very curious about the new project!
My friend is finally going to finalize the FHXL for the MA11MS and I'm asking him to help me with the Silbury for the MA10.3.
FHXL have been built with 18mm birch plywood, and I would do the same for the Silbury. Is it recommended to use higher width?
Of course I'll apply the new suggested bracing.
FHXL have been built with 18mm birch plywood, and I would do the same for the Silbury. Is it recommended to use higher width?
Of course I'll apply the new suggested bracing.
As for the hole for the MA10.3, I've found this drawing online:
So it is needed to have:
Is it correct? Thanks again
So it is needed to have:
- a hole-through with a diameter of 137 mm;
- a frontal annular cut with a diameter of 165 mm and a depth of 10.5 mm;
- a rear chamfer at 45° (except around the 6 holes to fix the speaker.
Is it correct? Thanks again
Completed the second cabinet and got a chance to listen to the pair for a few hours today.. My first impressions are very positive, these project height and scale commensurate of their ~1.8 m height. I have them about 1 m (to the front face) from the front wall and will experiment with positioning but at more than 120# each (turns out my carbon fiber / epoxy impregnated supply ply is bloody heavy) moving these more than a tweek is a commitment. I intend to get some furniture sliders to aid in the process. With the BLH design, do they benefit from the front-wall boundary? I have not pushed the MAOP 11's yet but there is plenty of detail and low end strength.. With ~5 degrees of toe-in, the central image is defined but not collapsed to a point-source zone; however I find the sweet spot extremely tight. Leaning to one side of the chair develops a strong L or R bias and evaporation of that central image. I have never experienced such a critically tight sweet-spot. My listening spot is 2.5-2.75 from the front baffle in a well damped / defuse room. Any thoughts on boundary placement / sweet-spot expansion would be most welcome, currently I have no stuffing in the horn . Will finish the glue up next weekend and prep the wood for primer..
After 20-30 hours I was impressed with the MAOP 11's in the Silbury cabinet design. Bass extension was good and soundstage was sufficient but there was a terribly narrow sweet spot, shifting my seating position +/- 6" completely destroyed the stereo image and central imaging was mildly disappointing.. At this stage the cabinets were "mostly" assembled with the final side panel held in place with clamps. Mind you, a lot of beefy clamps in every axis I could support with clamps, however placing my hand on the L & R side panel there was an immediately obvious difference in vibrations felt between the glued and clamped panel. I must admit, this was quite a surprise, the "clamped panel" was firmly secured to the cabinet with ample points of contact but goes to show how critical bracing in cabinet enclosure can be. I found adding 50g of well separated Mundorf Angel Hair to the final leg of each horn improved perceived quality. I was a little hesitant to continue the build given the unacceptably narrow sweet spot and weak imaging but pressed on.
Completing the glue up was relatively straightforward as was lining the diver chamber with 1/2" felt.. I put a 45-degree chamfer on the front baffle (given the 38mm thickness I used a 2" chamfer bit which is a little nerve racking). The first 2k epoxy primer has been applied to the completed cabinet, (the rear folded horn exits are a little tricky to paint) and IsoAcoustic Gia II footers have been installed on Al outriggers. Each cabinet weighs in a 112#.
Moving these into my music room I was prepared for a minor improvement on my initial experience; how wrong I was!
My initial impressions from the "clamped" cabinets are a sliver of the fully glued cabinets; the depth and soundstage have expanded significantly, the central images coalesced into a 3D voice with height and presence while the bottom end tightened up and appeared more forceful. Most surprisingly, that ultra-narrow sweet spot for the "clamped" cabinet has blossomed, no longer do I feel the "head in a vice w/ laser beam sound".. If you told me all this was possible with replacing 8+ clamps for some glue I would have said "No way".. The change was immediate and can not be connected to additional hours of driver break in.
I have about 50 hours on these now and am selling my beloved over-the-top GR Research NX Studio's; the MAOP 11 / Silbury is hands down the best audio experience I have had in my room. full stop. The general consensus regarding the break-in period for the MA drivers seems to be 100-200 hours so I have a way's to go and will be doing so eagerly.
The Silburys are big, mine are heavy, finishing can be tricky with the detailed hand sanding of the horn exits, but I enthusiastically recommend this cabinet design to interested parties.. I will continue the filling / sanding process and will be spraying these in either a BMW Alpine White or Ferrari Rosso Corsa in the months to come.. so much sanding ahead of me.
Hey!
I think the beveled baffle has a big impact on the larger sweet spot.
I've noticed that with my builds. Looks like you have a little more toe in now.
Can also affect. Sometimes I try toe in so they cross 2 foot, 0.6m in front of me. There is a lot to test.
Have seen that an extra baffle is used where the element is placed. Type ovoid, oval shaped. Haven't tried this unfortunately.
Congratulations on the successful build. He who seeks finds.
Regards
Leif
Sorry for the newbie question, can I ask you why? I have to say that it looks also better with it.
I'll start building them shortly with MA10.3 speakers for my living room.
Are them like silentblocks? Or can be substitued with silentblocks? How much is the sound improved by them?