Question Subwoofer box volume

tannyh

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I'm taking the plunge with some DIY subwoofers but I'm a novice with all of this and looking for some advice.

I've purchased x2 lavoce san214.50 to be powered by an inuke 6000. The plan is to get some cabinets made by Gordy but I'm unsure as to the best size of box to go for.

I'd prefer to go for sealed to keep the box size smaller. Not the best with Winisd but would I stand to lose output below 20hz if I were to go for a compact enclosure - say around 100l?

Thanks in advance!

Tan
 
Those drivers won’t work brilliantly in sealed enclosures, they are really designed for larger ported boxes in mind. UM18s are a better option if you want small sealed cabs.
 
Thanks for getting back to me Liam

I was mainly going by the databass website where the output appeared to be similar for this and the um18s in a sealed enclosure?

I have seen the ported boxes which I know will give me more output but I don't think I can accommodate them.

If I was to go sealed would I lose much output if I went with a smaller cabinet than the databass one which is ~4.5cu ft internal volume?
 
For some reason I thought you were talking about the 18” LaVoce and not the 21. In this case yes as you say equal to the UM18 down low with more midbass. An enclosure of around 100-120l is probably good for this driver. You don’t lose output with smaller enclosures, you just need more power to get there!
 
Well I've gone for an inuke 6000 so not massive amounts of power.

Just a rough check of my calls, If I go for an internal box size of
21.5 * 21.5 * 15

I've worked the volume out to be 113l. Im just confused on how I would accurately calculate how much the bracing elements would reduce this further or is it always a rough guess?

Does wadding also factor into the calculations?
 
You don’t lose output with smaller enclosures, you just need more power to get there!
minor nitpick, even if you have enough amp then you can still lose output due to power compression (or in worst case, melt the thing!). Obviously you need to be driving them pretty hard to do this :)
 
minor nitpick, even if you have enough amp then you can still lose output due to power compression (or in worst case, melt the thing!). Obviously you need to be driving them pretty hard to do this :)
Sorry should’ve been more clear, I meant for minor changes in box volume while staying in a certain range, ie from 100l to 120l. Obviously you may be able to physically fit the driver in a 60l box but the power needed to reach excursion and the thermal issues that would arise from this wouldn’t be ideal!
 
Well I've gone for an inuke 6000 so not massive amounts of power.

Just a rough check of my calls, If I go for an internal box size of
21.5 * 21.5 * 15

I've worked the volume out to be 113l. Im just confused on how I would accurately calculate how much the bracing elements would reduce this further or is it always a rough guess?

Does wadding also factor into the calculations?
With sealed boxes volume is less of an issue than with ported where the tune is affected. As long as each panel is braced every 20cm in any direction you should be good to go. I also wouldn’t factor wadding into the equation.
 
It seems that a box size within the range 100-140l shouldnt provide vastly different outputs. With the lower end of the volume size requiring more power to achieve the same output?

Ok going to go with an internal box size of 21.5 * 21.5 * 15 to make the boxes more discreet.

Thanks for all the help, no doubt I'll have more questions as the build progresses.

Cheers for all the help
 
Yes i have a umik1 already. Not looking forward to delving into REW as it's not the most user friendly😨
 
I'm taking the plunge with some DIY subwoofers but I'm a novice with all of this and looking for some advice.

I've purchased x2 lavoce san214.50 to be powered by an inuke 6000. The plan is to get some cabinets made by Gordy but I'm unsure as to the best size of box to go for.

I'd prefer to go for sealed to keep the box size smaller. Not the best with Winisd but would I stand to lose output below 20hz if I were to go for a compact enclosure - say around 100l?

Thanks in advance!

Tan

Different drivers I know but I went down a similar route - twin 88L Gordy enclosures - and have been very happy with the outcome. I endorse the need for lots of power but I also started with an iNuke 6000 and that's a very good start. I don't think you will be disappointed. Good luck with the build. 🤞
 
Just out of interest @Ringnut what drivers did you go for?
 
I've just gone through your build thread- the finish on your cabinets looks great👍. I'm still pondering on which finish to go for so as to make them more discreet.

Not sure I understood the cable tie method to install the drivers though.
 
Not sure I understood the cable tie method to install the drivers though.

I looped two cable ties between opposing holes in the rim of the driver which then allowed me to lower the driver into the cut-out without trapping my fingers, then I cut the ties and pulled the remainder of them out.
 
just wondering if anyone could give me a hand with eq using REW?

ive attached a copy of the subwoofer measurement that i got on the center channel without the center connected. the response is dominated by 2 peaks and 2 nulls. Is this a response i could potentially flatten?

my room is 6.07m x 4.57m and im sat around 1.8m from the back wall. I'm limited by how far i can move my seating position forward due to the position of the fireplace.

i have an mdat file with various other measurements of the front 3 without the subwoofer in an mdat file if these are of help?
 

Attachments

  • subgraphnoeq.jpg
    subgraphnoeq.jpg
    68.2 KB · Views: 94
ive zipped my mdat file of rew sweeps with a timing reference if theyre of any use
I'm still getting to grips with REW so not sure ive done all the measurements right but any pointers would be great -
 

Attachments

  • firstest.zip
    5.8 MB · Views: 46
Measurements look ok. What's your crossover set to? You seem to have a huge overlap between mains and subs.

Is it just the single sub? If so only placement will resolve/move that null at 40Hz. It's pretty narrow though so it might be the least worst option.

What's the difference between "sub no main" and "sub no main and no eq"?
 
Thanks for having a look Conrad, glad to hear the measurements look ok as configuring rew using my Intel nuc was painful.

Crossoverer is set to 80hz. I turned off Dirac for the sweeps as I thought this should be done after setting up the subwoofer. Similarly Im not sure I calibrated the levels of the front 3 to measure 75db before measuring. Is this what you mean regarding the overlap??

Just a single sub in the front right corner. The sub no main was with some filters set on my inuke from initially fiddling. Seems it's the same overall shape merely broadening the peaks.

Is this about the limit of what I'm likely to achieve with eq?
 
This is what I mean by overlap:

integration.jpg

The main looks good, it rolls off and, other than a couple of peaks, it's following an 80Hz crossover.

The sub though, that's still rising through 200Hz and is still as loud as the main at 280Hz. That doesn't sound right.

Did you measure the sub on the LFE channel?

Dirac sub no main looks better but I guess that's Dirac pulling the sub down.

What filters do you have in the inuke?
 
No I measured the sub on the center channel with the center disconnected. I see what you mean regarding the overlap- although would this not be resolved when I carry out my Dirac calibration?

The only filter I have on the inuke is the shelf filter for below 20hz - no other filters have been used for the sub no eq reading.

The graph you've attached appears to look better than the one I've attached, is this because of the limits you've used on the graph??
 
@tannyh Looking at going down the same route as you, LaVoce 21's, in a 131L~ sealed box, did you end up getting the boxes done by Gordy?
 
Yes I did. Id be as specific as you can with your design. I wanted boxes for downward firing subs which I didn't communicate, meaning the threaded inserts for feet were on the wrong side- my own fault entirely
 
Yes I did. Id be as specific as you can with your design. I wanted boxes for downward firing subs which I didn't communicate, meaning the threaded inserts for feet were on the wrong side- my own fault entirely

Interesting, any chance you have any photos?
 

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