I'll be building a pair of Spirit Winds by Jeff Bagby as soon as the kit arrives. These will be in honor and memory of him!
For WAF reasons, namely, my wife hates speaker stands, I've got to build them floorstanding. No bookshelves on stands in this house. So Im thinking the side and back panels will be longer, reaching to the floor, and the original dimensions will be there by means of a false floor inside the speaker cabinet. The baffle will be the original size, to deal with the 5 degree slant, and then will connect to a straight, flat piece that goes down to the floor or a base. It will be veneered, but I figure I can get the veneer to go over the 5 degree joint on the front pretty easily.
My sort of general question is, is this a good idea, or it will it just ruin the whole thing? And any tips or suggestions? Has anyone seen this or something similar done? Have pics?
For WAF reasons, namely, my wife hates speaker stands, I've got to build them floorstanding. No bookshelves on stands in this house. So Im thinking the side and back panels will be longer, reaching to the floor, and the original dimensions will be there by means of a false floor inside the speaker cabinet. The baffle will be the original size, to deal with the 5 degree slant, and then will connect to a straight, flat piece that goes down to the floor or a base. It will be veneered, but I figure I can get the veneer to go over the 5 degree joint on the front pretty easily.
My sort of general question is, is this a good idea, or it will it just ruin the whole thing? And any tips or suggestions? Has anyone seen this or something similar done? Have pics?
I think you'll be fine. The false compartment will also allow you a place to position your xover.
I would advise damping the elongated walls on the inside, as I made a soundbar with unused cavities, and they ended up ringing to the music played because there was no damping inside. In my case, stuffing was all that was needed, but maybe an adhered foam sheet might be all that is required.
Later,
Wolf
I would advise damping the elongated walls on the inside, as I made a soundbar with unused cavities, and they ended up ringing to the music played because there was no damping inside. In my case, stuffing was all that was needed, but maybe an adhered foam sheet might be all that is required.
Later,
Wolf
If you fill the bottom cavity with dry sand or similar the speaker will be rooted to the floor. I have also seen similar cavities used for helper (sub)woofers.
dave
dave
I was also thinking, damp the bottom part, at least partly with sand, and put a space for the crossover above it just under the speaker part itself. The sand will dampen the speaker as the unused part may resonate. And a brace on the bottom of the cabinet itself (under the normal bottom of the speaker) may also help to avoid that.
You could reduce the cabinet depth and use the available volume. I don't know the design well enough though. With floor stander cabinets always be beware of the vertical modal resonance and use some kind of volume damping (e.g. a piece of egg crate foam on a bracing panel) just below halfway the cavity. Move the reflex port to a position under that damping and it will have less port resonance.
Yes. Effective cavity damping on the port resonance frequency will reduce the port resonance output because the stimulus will be lower in level. Transmission loss through acoustic foam on frequencies of about 600-800Hz isn't great, but it's there. But you have to believe that port output is audible of course 😉
+1 on the angled bottom panel.
I personally don't like BR, so I would look at increasing box volume and running it sealed if there was extra volume that could be used.
I personally don't like BR, so I would look at increasing box volume and running it sealed if there was extra volume that could be used.
You can fight it, but if the aspect ratio gets too large the BR turns into an ML-TL and the tuningis no longer correct.
Foam is a poor damping material.
dave
Thank you all for the excellent tips. I had not thought of adding bracing to the cavity, that is a great idea, and not too difficult, so I definitely will.
As far as Damping, Im going to look into this. Im kind of hoping it doesn't have to be sand, just because, well, sand... I mean what else could I use? No kitty litter either, we have a cat and I dont need him using my speakers as, you get the idea. Maybe some sound treatment I could stick to the walls instead? If I do use sand how far do I have to fill it?
Regarding using the additional volume to reduce depth or other dimensions, could definitely work, but I'd rather not, the design alteration gets beyond my knowledge. I would rather keep it as close to the original design as possible while addressing my WAF issue.
The angled bottom that's been suggested, by this I think you're referring to my false floor that I mentioned in the first post. I've got to wrap my head around this. Try and digest it. I dont have the speaker plans yet, I guess they come with the kit. Give me a bit to process all this and I may see about working that in.
Really, thank you for these suggestions guys, exactly what I was seeking with this thread!
As far as Damping, Im going to look into this. Im kind of hoping it doesn't have to be sand, just because, well, sand... I mean what else could I use? No kitty litter either, we have a cat and I dont need him using my speakers as, you get the idea. Maybe some sound treatment I could stick to the walls instead? If I do use sand how far do I have to fill it?
Regarding using the additional volume to reduce depth or other dimensions, could definitely work, but I'd rather not, the design alteration gets beyond my knowledge. I would rather keep it as close to the original design as possible while addressing my WAF issue.
The angled bottom that's been suggested, by this I think you're referring to my false floor that I mentioned in the first post. I've got to wrap my head around this. Try and digest it. I dont have the speaker plans yet, I guess they come with the kit. Give me a bit to process all this and I may see about working that in.
Really, thank you for these suggestions guys, exactly what I was seeking with this thread!
Last edited:
Maybe the tuning wasn’t correct anyhow. Bass tuning always is a shot in the blind if you don’t know the room and position of speakers and ears. And a reflex in a tube form enclosure has been done before, with succes.
As for foam I don’t follow your statement. I could throw all kinds of absorption characteristics here which clearly prove it wrong. A lot of anechoic rooms have been constructed with foam wedges. It can be a fine damping material. The right foam is as good as mineral wools. What better materials you can think of? Apart from aramid fibers there aren’t a lot.