Cantilever BOSS Build

markymiles

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So finally thought I'd give it a go and lifted my sofa ready to take measurements etc. I guess that's the end. Shame. :D

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Thought of doing a Cantilever Boss ?
 
A full riser BOSS would still be OK, or as Stoke mentioned a Cantilever.. Failing that, new sofa ;)
 
Which one ?. I'm not getting a new sofa just so I can do a boss LOL.

Yeah I'll have alook at other options. I don't really fancy raising my sofa that much though for a full riser. Ok in a dedicated room, think it would look a bit odd in a lounge.

Will see what this cantilever business is. I do get TR from my NF subs which are right behind the sofa back, but fancied trying a BOSS out which seem better and easier to Eq.
 
OK so had a look and Cantilever will work :smashin:.

Only slight issue is exposed drivers, the cats have already chewed through a network cable behind the sofa.
 
You could try boxing them in a bit, just leave a gap to they remain open baffle
 
I think one of the guys over on the AVS did just that, I think it was 3 sides and covered in speaker fabric to tidy it up.
It’s somewhere in that thread, not sure where though, it’s a long thread!
 
Ok so after a couple of weeks mucking around doing other things decided to have a go. Ordered a sheet of ply, unfortunately no driver available today to deliver it. So have to wait a week. Gives me time to order anything I need.

As they are just sat there currently as NF subs and all wired up can't think of anything I need other than feet. So go for these Hudson ones or something cheaper?


Which ones of these have been tried and tested size wise? Don't want to scrimp but also don't want to waste money..... I have loads of squash balls cut in half, when I thought they made a difference to my kit. Would they work if I used enough of them or not strong enough?
 
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I've tried the squash balls Mark. Even filled them with silicon to firm them up. These didn't work out. So I ended up with dogs balls from pets at home, £1. a pop.. Same size as the Hudson's too (once cut in half). They hold weight yet are spongy.

 
I'm using the pets at home balls with my Boss, they do seem to compress a fair amount even with 9 in place. Looking at the design weight for the Hudson's they quote 60-100lb for 4 feet for the big foot , so even with 8 it barely covers a full grown adult and a small chunk of sofa. Either way the Boss seems to work very well 😁. Makes me wonder would it be more responsive with more feet spreading the load.
 
Thanks chaps. Will get some of those then. As they are in packs of 6 might as well get 12.
 
Ok that's me ready for the ply tomorrow :)

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As I clearly have lots, is there any issue with using plenty. I was going to go with 12 but can go up to 24 if need be. Seems like the drivers need to be surrounded at the back with say 4 each as that's where the movement is.

Also the clearance isn't going to be that much underneath if the surround is below the board. Gives me more momentum to have lots of balls as they then won't compress as much.
 
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Are you using inner tubes with your build?, I found with just the half balls in place the inner tube was actually lifting the platform up, when weight went on the platform it was causing excursion on the drivers, I ended up putting some 10mm thick timber on the floor for the balls to contact with giving me around 40mm clearance from the floor.

The balls do seem to compress a fair bit on mine. Would be good to see how much the Hudson dome compresses vs the sponge balls.
 
Are you using inner tubes with your build?, I found with just the half balls in place the inner tube was actually lifting the platform up, when weight went on the platform it was causing excursion on the drivers, I ended up putting some 10mm thick timber on the floor for the balls to contact with giving me around 40mm clearance from the floor.

The balls do seem to compress a fair bit on mine. Would be good to see how much the Hudson dome compresses vs the sponge balls.

Post #83

 
No I am not going to bother with inner tubes. I get the improvement, but a stage too far for now.

Over thinking it as usual, I can always add more balls if needed. I am going to go with 14 to start with on a three seater. I'll add some timber for under the balls too to get more height if needed.
 
I used additional spacing as the rubber feet squashing and the small enclosure for the driver formed by the inner tube was putting pressure on the driver and with just me standing on the platform I could see lots of excursion on the driver, with the 10mm timber to raise it up this pretty much stopped the excursion issue. As your not using tubes then I don't believe clearance would be an issue.
 
Cheers. Rain almost stopped play but just managed to do what I needed.

I think the balls add comedy value. Need to paint around the edges black but other than that done. Just waiting for the glue to dry.

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Ok count me as a convert. As it turned out I didn't seem to have any black paint so thought I'd better give it a go instead. :smashin:

I was wondering if the cantilever effect may not be so effective. I needn't have worried. I lowered the power on the inuke to around 200w, and wound the attenuator to min. Already had the flat eq settings (-4db hs12 20hz) entered on the inuke, no idea if needed anything else. Loaded EOT start obviously. Cautious volume to start with.

Bloody hell. Not had anything like this. I think the last tone is 10hz? It was actually doing something effective that low. All tones felt really natural. Really really impressed. So much better than NF subs and also shakers I have tried in the past.

Only really need to get the volume right then that's it. Thanks to @paulst10 whose thread sparked interest to give it a go.
 
Good to see another convert!, Added tubes to mine today :eek: certainly ramps up the intensity, Saving private Ryan beach scene (with BEQ) is incredible :D

Question about attenuation, as the NX manual is unclear, I have mine set to 3 o'clock as per the instructions in said manual.
What does it actually do ?

Thanks
 
Good to see another convert!, Added tubes to mine today :eek: certainly ramps up the intensity, Saving private Ryan beach scene (with BEQ) is incredible :D

Question about attenuation, as the NX manual is unclear, I have mine set to 3 o'clock as per the instructions in said manual.
What does it actually do ?

Thanks

The attenuation knob just attenuates the input signal, ie reduces it. Ideally I think it should be set at fully clockwise as this is leaving the signal intact. You then adjust the gain in the dsp settings, assuming you have a DSP version. I don't bother doing this to be honest, and just use the knob as a volume control which is easier than having to play with the DSP. At fully open and zero gain my subs are louder than my speakers so a reduction is needed somewhere. Like you I've ended up around 3:00.

The aim of the exercise is to get the loudest you can without clipping, but I get a little bit lost with gain structure.

Coming back to the BOSS. I do find the sofa is a bit wobbly just by people moving around a bit. This sensitivity is useful for the subs but a bit annoying every time someone moves. Not sure if different feet would make any difference.
 
Ideally I think it should be set at fully clockwise as this is leaving the signal intact. You then adjust the gain in the dsp settings, assuming you have a DSP version
No that is not right, if you do that the signal will clip on the way in (if the max output from the upstream device is more than the input sensitivity of the inuke)
 
No that is not right, if you do that the signal will clip on the way in (if the max output from the upstream device is more than the input sensitivity of the inuke)

Yep as I thought, I get a bit lost with gain structure. Felt sure I had read that somewhere. Is the upstream device likely to clip the inuke though. I don't know the input sensitivity off the top of my head but I thought that being PA amps they were expecting a higher input signal anyway?
 
the inuke has consumer style input sensitivity when no attenuation is applied (~0.8V iirc) via the gain knob so it's almost certain you'd need to attenuate, for example a marantz or denon AVR can produce something like 7V (so about 18dB too much)
 

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