ps two 1.5" holes drilled in the front. slide some dark grey sched 80 pvc pipe (1" id ) \for the ported test
OK, then not ~aperiodic enough, which means not enough damping applied, so historically, fine tuning any type vent is to 'critically' damp it, i.e. ~transient perfect (no 'hangover'/'boom').
I cut out the original inset back. Added a frame and replaceable panel (solid wood lined with mdf on both sides, smaller vents, its getting there.
The rectangles come out to 12.25sq inches, I'm covering the opening with aquarium filter sponge (fine,open cell foam) The denser the material the foam better it sounds, memory foam was too dense
So no array of 21 x 0.9" holes as you previously mentioned, but two rectangular resistive vents instead?
I think I'm a little confused. It must be an age thing!
GM seems to be following but, after all, he's the expert. 🙂
I think I'm a little confused. It must be an age thing!
GM seems to be following but, after all, he's the expert. 🙂
Definitely in my case, but 'assumed' from these posts that he decided to just test with (dual?) vent(s) and didn't like the results, hence now trying large slots to experiment with aperiodic Vs all the tedious hole drilling.
I'm currently taking the opportunity to enjoy the combination of aperiodic bass and concrete a floor (my listening room is almost a cube with a wooden floor), the aperiodic vent is a rectangular hole with a perforated steel "grill" to add resistance, it seems to work as well as lots of drilled holes.
I should have said 'mostly' backed with felt cloth instead of 'partially'. Just something to note if experimenting. I'd be inclined to go for 'completely' covered in the first instance.
My aquarium sponge is working fine, but before I cut it and permanently ruin it. I was thinking of trying out felt, then though... what about Tyvek fabric as a vent cover. It's used to breaks up drafts (and sound from drafts), allows for air penetration, waterproof, cheap, and very thin. Fold it over as many times as needed to get the desired density.
Might even be usefull as speaker mesh.
Vertical surfaces sitting near the floor/wall runs a risk of cat peeing on it, tyvek might be a good permanent solution to protect the woofer
Might even be usefull as speaker mesh.
Vertical surfaces sitting near the floor/wall runs a risk of cat peeing on it, tyvek might be a good permanent solution to protect the woofer
Tyvek is new to me, but the 'soft structure, fabric like finish' variety may be suitable for your purposes - you can but experiment.
It's probably the wrong thing to do but I went with poly fill and fiberglass. FG paper backing makes it much easier to line the walls. I cut fishnet stockings and stapled it above/bellow the port which made it a lot easier to stuff a dense and even layer of PF over the port. (I didn't want to pull apart layers of FG and get it everywhere so PF for everything other than the the 5 squares of FG.
Dialogue sounds much better on it
Weirdly, my box is louder at 80-90hz than the original larger ported enclosure was. Db response is the same at 140hz for both. Original enclosure was 66db at 45hz, this one is doesn't hit 66db at 60-65hz.(I didn't test it any proper way, or with a quality mic but did it consistently on both enclosres.
Dialogue sounds much better on it
Weirdly, my box is louder at 80-90hz than the original larger ported enclosure was. Db response is the same at 140hz for both. Original enclosure was 66db at 45hz, this one is doesn't hit 66db at 60-65hz.(I didn't test it any proper way, or with a quality mic but did it consistently on both enclosres.
Do you regard this as a satisfactory outcome, or will further experimentation follow?
No this is great, thank you everyone.
The goal was to replace a too tall enclosure without losing sound quality. The new one fits and sound better. It's the 1st DIY that will be used for its entended purpose.