I'm thinking to build one of those distributed sub system things a la Geddes style.
Whole system is currently a 2.1 (2.8 if we pull the trigger on the idea).
80% music, 15% movie, 5% game, a very agreeable SWMBO and fairly loud listening (we party a bit).
So far I am considering the following components:
Minidsp 2x4 HD (1)
ART Cleanbox (2)
Sinbosen FP10000Q 4 channel amp (1)
Dayton Ultimax UM10-22 (8) each in 1 cuft sealed, wired two per channel all series to present 8 ohms to each amp channel.
This would supply each driver with ~675 watts, just over what they will be happy with but a ~15hz highpass should at least keep excursion in check.
I haven't found a driver that would do better in a 1cuft sealed enclosure than the UM10.
So my questions are these:
Does this configuration look feasible?
Is there a better driver out there for small sealed enclosures in this implementation?
TIA
Whole system is currently a 2.1 (2.8 if we pull the trigger on the idea).
80% music, 15% movie, 5% game, a very agreeable SWMBO and fairly loud listening (we party a bit).
So far I am considering the following components:
Minidsp 2x4 HD (1)
ART Cleanbox (2)
Sinbosen FP10000Q 4 channel amp (1)
Dayton Ultimax UM10-22 (8) each in 1 cuft sealed, wired two per channel all series to present 8 ohms to each amp channel.
This would supply each driver with ~675 watts, just over what they will be happy with but a ~15hz highpass should at least keep excursion in check.
I haven't found a driver that would do better in a 1cuft sealed enclosure than the UM10.
So my questions are these:
Does this configuration look feasible?
Is there a better driver out there for small sealed enclosures in this implementation?
TIA
Good question. I would say yes and no. The amp would reside in a rather large under staircase closet. The closet is not completely acoustically isolated so a quiet fan option may still be used. Worst case the amp could be located in the unfinished basement below.
I guess that could be a third question.
Is there another non-bank-breaking amp option that I should be considering?
I'd also consider the Behringer NX series. A pair of NX6000D would do DSP duties and have ample power output.
They, too, need silent fans, but are easy to modify.
Chris
They, too, need silent fans, but are easy to modify.
Chris
The Behringer options are also on my radar. One amp chassis is the main reason for looking at the FP10000.
Ah, but the DSP + Art Cleanbox x2 adds several more boxes.
IIRC, the NX series amps have enough gain to be driven direct from HiFi equipment.
The Behringer amps will also get you a warranty, which is nice.
It's your call, but if it was mine I'd go for 2x NX6000D.
Chris
IIRC, the NX series amps have enough gain to be driven direct from HiFi equipment.
The Behringer amps will also get you a warranty, which is nice.
It's your call, but if it was mine I'd go for 2x NX6000D.
Chris
For 80% music I would go with Dayton Reference series:
"RSS265HO-4" - it models 9.8 liter (0.346 cu ft) with Qtc=0.7
Undeniable small size advantage.
Less output below 50hz. 2-4 db less. May never notice this.
Probably the lower distortion design driver? Might notice this more than output?
Less expensive.
Nicer looking IMO.
I thought I had compared UM10 to this but it seems to be closer than I realized.
Nice suggestion Will P. Thanks for that.
Less output below 50hz. 2-4 db less. May never notice this.
Probably the lower distortion design driver? Might notice this more than output?
Less expensive.
Nicer looking IMO.
I thought I had compared UM10 to this but it seems to be closer than I realized.
Nice suggestion Will P. Thanks for that.
Makes little sense to me but I guess there are factors not obvious in post #1.
The multi-sub concept starts working with 2 subs, gets better with 3, and tops out at maybe 4.
I haven't made up my mind if a mixed bass is better or stereo bass is better. Prolly mixed. In which case, you don't need so many amps and the exaggerated power is a common exaggeration on this forum.
Instead of one or two great subs (read: 6 cu feet), you seem to want 8 dinky little ones none of which go low. Makes no sense to me.
While there's a certain simplicity in making 8 identical boxes that appeals to the engineering mind, it is heterogeneity in the real world that makes for great bass and the Geddes approach (spread of locations around room for subs) is exactly that.
B.
The multi-sub concept starts working with 2 subs, gets better with 3, and tops out at maybe 4.
I haven't made up my mind if a mixed bass is better or stereo bass is better. Prolly mixed. In which case, you don't need so many amps and the exaggerated power is a common exaggeration on this forum.
Instead of one or two great subs (read: 6 cu feet), you seem to want 8 dinky little ones none of which go low. Makes no sense to me.
While there's a certain simplicity in making 8 identical boxes that appeals to the engineering mind, it is heterogeneity in the real world that makes for great bass and the Geddes approach (spread of locations around room for subs) is exactly that.
B.
Dayton Reference series is designed for sound quality.
I have (32) of the "RSS265HO-4".
They provide the most cone area per box volume. You can install (2) opposed in a box (12.5" x 12.5" x 14") with Qtc=0.7
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It's the law of diminishing returns. Things don't start getting worse with 5+ subs, it's just that the improvements get smaller.
I'd say the amplifiers being discussed are appropriately sized - they certainly won't be the limiting factor here, and that's a Good Thing.
So what if they won't go low anechoically? They're going in a room, and EQ is part of the plan (as it should be).
FWIW, here's a couple of curves:
Simulated:
At listening position:
That's for an 8" driver in a sealed box, and I'm using one per side.
While the simulations suggest I wouldn't have much LF extension, after I cut down the 40Hz mountain and 70-80Hz hump, my final LF rolloff happens around 10Hz - a much more impressive figure.
I don't really see the argument for using a bunch of different subs in the same room. It's just another layer of complexity to unwrap.
Kevmoso, it's occurred to me that you could run the entire thing off 1x NX6000D. Put the voicecoils in series, and then put 4x cabs in series-parallel on each channel. The amp would be working at 4ohm/ch and putting out around 450w/sub. You'd lose some DSP control, though, since you'll only be able to process 4x subs at a time.
Chris
Other responses have addressed many of the reasons I am thinking of this path.
The Harman study, https://www.harman.com/documents/multsubs_0.pdf suggests that up to 5000 subs can be beneficial. lol
4 may be a practical sweet spot but why build 4 when you can build 8 for twice the price?
The factor that I maybe should have included in my original post is that I do not want two or even one small refrigerator size sub in the room. I can stash 8 or even more tiny subs all over the place.
4 dual opposed rss265s has me pretty intrigued at this point.
I may be wrong, but i think to do the multisub thing correctly you need to have independent control (phase, level and eq) of each of the subs. You will gain a little output by adding extra subs but not necessarily smoother bass throughout the room.
One simple way to assure smoothest bass throughout the room (the whole room, not just the LP) is to have all the subs identical, with identical EQ, identical phase , identical delay and placed in a grid pattern on the floor so that their acoustic reflections off the walls continue the grid pattern and spacing distance. Sub-to-sub distance is to be less than the 1/2 of shortest wave length (HPF frequency; for 80Hz that is 7ft max between subs).
For room with dimensions 21ft x 14 ft the pattern would be (6) subs in 2x3 subs pattern, 7ft between subs, 3.5ft from each sub to the closest wall.
Another way to get smoother bass is to use Double Bass Array which is using the same pattern but placed vertical on the front wall. At the back wall the same subs pattern but with inverted signal (180 deg phase) with added delay based on room depth so most of the subs sound waves to get cancelled - similar to active bass trap.
Every time the number of subs is doubled - the output SPL goes up by 6dB.
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I wish it was that simple. Not sure I'm qualified to respond to this so hopefully someone with more experience will chime in to say why this won't really work for everyone. Mr. Geddes has spent a good portion of his life devoted to studying and researching this topic so with all due respect I will probably follow his setup.