Alpair 12...Solstice building questions!

[Urchinn]

Just ordered my Alpair 12's from Madisound (they seem pretty nice over there!). On February 12th, my AudioKarma members and I will be building a beta version of the Solstice speaker design. Anybody know if there is supposed to be some baffling material inside the Solstice? Insulation, or wool, or felt, or whatever. Please feel free to give me your thoughts here. There will be about 20 people attending this build...and not a single one of us has built their own speakers. Yup, I'll provide alot of photos when this all goes down.
Thanks...Tony

[skeeter99]

Originally Posted by Urchinn

Just ordered my Alpair 12's from Madisound (they seem pretty nice over there!). On February 12th, my AudioKarma members and I will be building a beta version of the Solstice speaker design. Anybody know if there is supposed to be some baffling material inside the Solstice? Insulation, or wool, or felt, or whatever. Please feel free to give me your thoughts here. There will be about 20 people attending this build...and not a single one of us has built their own speakers. Yup, I'll provide alot of photos when this all goes down.
Thanks...Tony

Very cool! I was talking with Scott and Dave about beta testing those cabinets! I can't speak directly about the baffling but I'm sure one of those two will chime in. Congrats and as you said, LOTS of pics

EDIT: I just looked, where on AK is the thread? I couldn't find it searching.

[vinylkid58]

Originally Posted by Urchinn

There will be about 20 people attending this build...and not a single one of us has built their own speakers.

[Urchinn]

I guess I should also mention that although nobody has experience with speaker building, at least 6 of these Audiokarma people can fix their own tube amps, restore turntables, etc. A very knowledgeable bunch. Also, we are meeting in an old factory which has an amazing woodworking office on the first floor...owned by a master carpenter...with restored Altec Voice of theTheater speakers in the corner. A very congenial place to assemble a Solstice! Don't worry, Skeeter, I may be a newbie in the full range world, but you gotta start somewhere. I will post tons of pics, and report how the fabled Alpair 12 break-in goes. Perhaps I should have gone with the Super Pencil design...but half the beauty of audio equipment is design. Why not the triangular looks of the Solstice?

[skeeter99]

Originally Posted by Urchinn

Don't worry, Skeeter, I may be a newbie in the full range world, but you gotta start somewhere. I will post tons of pics, and report how the fabled Alpair 12 break-in goes. Perhaps I should have gone with the Super Pencil design...but half the beauty of audio equipment is design. Why not the triangular looks of the Solstice?

Well I'm a total newb with speaker design too so its all good! Still have yet to build my first set I'm the "picture police" on most of the forums I'm on so I'm all about taking and sharing pics. I really learn visually and less from reading a spec sheet so I'll definitely be following your progress

The SuperPensil design is fantastic looking and probably what I'll end up building but the Solstice sure did look nice! Can you give us some details on what you're using for materials/finish/etc? And who gets to take them home once you're done?? LOL!

Scott

[planet10]

Did Scott or i get you the plans (i remember us talking about your effort)... my brain is a bit foggy from a couple rounds of the "plague".

I ask because this info is in the plans -- and i haven't yet expanded the planset beyond the basics. Solstice is volume filled with polyfluff similar to a pensil or a TL/ML-TL

dave

[Urchinn]

Scott sent me the plans...but I don't remember any "polyfill" info (the plans are currently with my friend/carpenter. Where do you buy polyfill, and how much should you pack in there? Any info would be great.

[planet10]

The detail is in the notes (if not contact me directly, cause i'll have a bit more complete set here). Polyfill, polyfluff, dacron wool is usually had at a cloth or craft store.

Tease the specified amount out as evenly as possible and fill the top 2/3rds. From there you will need to adjust to suit -- when we did Pensil7 we ended out pulling out about a 1/3rd but found no need to fill the remaining volume. The spec is to be considered a starting point.

dave

[Urchinn]

Okay, I've got the beta plans back. I see the notes about dacron filled from the top of the cabinets to "just below the driver." One question: If filling the top, how do you get the polyfill to stay put? Presumably it must be anchored to the top part of the cabinet somehow or it would fall to the bottom of the cabinet. Does that make sense? Thanks.

[chrisb]

Originally Posted by Urchinn

Okay, I've got the beta plans back. I see the notes about dacron filled from the top of the cabinets to "just below the driver." One question: If filling the top, how do you get the polyfill to stay put? Presumably it must be anchored to the top part of the cabinet somehow or it would fall to the bottom of the cabinet. Does that make sense? Thanks.

Plastic window/door screen mesh from the local hardware/building supply.

Be sure to fabricate with back panel removable to allow for adjusting levels of fill.


Will you be incorporating panel bracing as is generally "suggested" in Dave & Scott's plans? I frankly wouldn't build any enclosure these dimension without at least front to back vertically oriented bracing, if not side to side as well - as per below. While not the same style of enclosure as the Solstice, this bracing format would still work.

Cut lots of larger diameter openings with hole saws and align the bracing to side of center line.