Hey Folks,
I would do this myself but I don't have access to a windows computer right now and I need to make a decision in the next day or so.
I'm looking at the RSS315HE-22 dayton subwoofer.
https://www.daytonaudio.com/images/resources/295-291--dayton-audio-rss315he-22-spec-sheet.pdf
I've tried having a play with hornresp (I actually managed to make it work on my mac), but have had no luck with WINISD.
It looks like a very small sealed box, ~25L gives a Q= .7, but it reaches max displacement really quickly.
My biggest issue is that I don't know how to model a bass boost for a sealed system in hornresp.
I've tried playing with a ported box, and ~80-90L gives a good response, but the port ends up being very very long to reduce port velocity below 17m/s.
Could someone have a quick bash at modelling this and seeing what an optimal design would look like?
I tried searching on the forums for previous modelling and didn't find much if any!
I'm looking for <100L Box with decent response down to 20hz.
I know I'll need a heap of wattage to make this happen. A 105dB Max output would be perfectly acceptable for me.
A small(ish) box is the main priority.
I will have DSP available.
Thanks for your time, even if it was just giving this a quick read.
Thanks!
I would do this myself but I don't have access to a windows computer right now and I need to make a decision in the next day or so.
I'm looking at the RSS315HE-22 dayton subwoofer.
https://www.daytonaudio.com/images/resources/295-291--dayton-audio-rss315he-22-spec-sheet.pdf
I've tried having a play with hornresp (I actually managed to make it work on my mac), but have had no luck with WINISD.
It looks like a very small sealed box, ~25L gives a Q= .7, but it reaches max displacement really quickly.
My biggest issue is that I don't know how to model a bass boost for a sealed system in hornresp.
I've tried playing with a ported box, and ~80-90L gives a good response, but the port ends up being very very long to reduce port velocity below 17m/s.
Could someone have a quick bash at modelling this and seeing what an optimal design would look like?
I tried searching on the forums for previous modelling and didn't find much if any!
I'm looking for <100L Box with decent response down to 20hz.
I know I'll need a heap of wattage to make this happen. A 105dB Max output would be perfectly acceptable for me.
A small(ish) box is the main priority.
I will have DSP available.
Thanks for your time, even if it was just giving this a quick read.
Thanks!
Greets!
T/S max flat:
Vented net volume (Vb) (L) = 20*Vas*Qts'^3.3 = 50 L
Vented box tuning (Fb) (Hz) = 0.42*Fs*Qts'^-0.96 = ~28.3 Hz
F3 (Hz) = Fs*0.28*Qts^-1.4 = ~26.6 Hz
Yes, extremely long as in TL long with 2x Vb (100 L) dropping Fb = ~21 Hz, lowering vent mach and factoring in only needing ~120 W/105 dB/20 Hz/2 pi it still needs a 'critically damped' 5" i.d. dia. vent x 31.1"/79 cm long, ergo ideally needs a single 15" or dual 12" passive radiator(s).
T/S max flat:
Vented net volume (Vb) (L) = 20*Vas*Qts'^3.3 = 50 L
Vented box tuning (Fb) (Hz) = 0.42*Fs*Qts'^-0.96 = ~28.3 Hz
F3 (Hz) = Fs*0.28*Qts^-1.4 = ~26.6 Hz
Yes, extremely long as in TL long with 2x Vb (100 L) dropping Fb = ~21 Hz, lowering vent mach and factoring in only needing ~120 W/105 dB/20 Hz/2 pi it still needs a 'critically damped' 5" i.d. dia. vent x 31.1"/79 cm long, ergo ideally needs a single 15" or dual 12" passive radiator(s).
Attachments
GM's numbers are pretty much bang on when sim'd in WinISD. This isn't much of a surprise. 😉
Here's a pic. Vent is 3" diameter x 11.5" long for ref.
jeff
Thanks gents.
Jeff, that seems a very reasonable vent size and frequency response. Especially when you add in some room gain around the 20hz mark.
How is the vent not stupidly long like I (and GM) found?
Are you able to see how much power it takes before xmax limit?
Cheers!
Jeff, that seems a very reasonable vent size and frequency response. Especially when you add in some room gain around the 20hz mark.
How is the vent not stupidly long like I (and GM) found?
Are you able to see how much power it takes before xmax limit?
Cheers!
How much EQ do you have?
It will work in 25-50 itres sealed and get you into the mid 20s F10, a good measure of where it will go in room.
I prefer sealed + EQ for subwoofers (ideally you have at least 2).
A 50 litre vented alignment tuned a bit lower than GM suggests gives a more damped response. 25 Hz in the sim below.
dave
It will work in 25-50 itres sealed and get you into the mid 20s F10, a good measure of where it will go in room.
I prefer sealed + EQ for subwoofers (ideally you have at least 2).
A 50 litre vented alignment tuned a bit lower than GM suggests gives a more damped response. 25 Hz in the sim below.
dave
It'll be full digital.
I assume a vented alignment would require a HPF. Probably either option to be honest.
The plan is to have 2 of them, in a 6m x 9m living/dining room. They'll both be within 2m of the sitting position, in different corners/room positions.
I was thinking sealed pushed to f10 at about 25hz, then adding a modest EQ boost of 6dB + room gain would actually pull it down pretty neatly to close to 20hz. But vented would also work very similar.
This is for 50/50 Music & movies. My biggest issue is size of enclosure and I'm just trying to make the best compromises I can.
Much too small as even the 5" needs fairly serious damping to get it down to ~20 m/s.
That is where i went with mine. It may well be more complex than that. Your room is pretty large, ceiling?
You may well not need a ot of lift, but room modes, even after you get the 2 subs placed so that they have the smoothest response you will likely still need a bit of tweaking here & there.
dave
@vinylkid58
Not according to HR in my #2 post.
edit: @ 310 W requires a 7" dia. x 136 cm/53.54", i.e. as I assumed, a TL length vent and after what has been posted since, really ought to make these a proper MLTL tuned down to where he wants/needs it.
Not according to HR in my #2 post.
edit: @ 310 W requires a 7" dia. x 136 cm/53.54", i.e. as I assumed, a TL length vent and after what has been posted since, really ought to make these a proper MLTL tuned down to where he wants/needs it.
Last edited:
True, but he asked for 'optimal', so started with the basics like I always do.........