If you were to build an enclosure that was flat to 20hz for 2 18s what alignment would you use. The drivers have 22mm xmax.
Sealed if size and money are an issue and good output is required.
OB if size and money are an issue and only moderate output are required.
Front loaded horn if size and money are not an issue and very high output is required.
OB if size and money are an issue and only moderate output are required.
Front loaded horn if size and money are not an issue and very high output is required.
I have a single 15 with 22mm Xmax that is flat to 20hz in my room
And I think it has “good” output.
Depends on what your idea of good output is but with 2 x 18s sealed I would think that you would be happy with the output
I usually try and aim for an overall Q of around 0.57 -0.6
And I think it has “good” output.
Depends on what your idea of good output is but with 2 x 18s sealed I would think that you would be happy with the output
I usually try and aim for an overall Q of around 0.57 -0.6
There is no mention of constraints or expectations so it's something of an open ended question anyway. And no, a single 15" would not satisfy me in a flat to 20Hz system, at least not sealed.
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Expectation and the goals is always key. My sub outputs more than a SVS PB13 ultra. Or about the same.
Some people think that’s a lot of bass. Others don’t.
I would say I’m at a point that when my second sealed 15 is built, I have enough.
Many enthusiasts would think that’s a puny system. But I think it’s fine.
Lots of systems can be flat to 20hz at low output.
When I say flat to 20hz I’m talking about maybe around 115db across the range for it to be satisfying enough for me.
Some people think that’s a lot of bass. Others don’t.
I would say I’m at a point that when my second sealed 15 is built, I have enough.
Many enthusiasts would think that’s a puny system. But I think it’s fine.
Lots of systems can be flat to 20hz at low output.
When I say flat to 20hz I’m talking about maybe around 115db across the range for it to be satisfying enough for me.
There is no way a single 15" will do 115dB @ 20Hz at the LP in my room, or many others I've built systems for, unless it is nearfield. I agree 115dB at 20Hz would be adequate for many people.
Flat to 20 Hz in a real room is hard, not the 20 Hz part (you do have to include the room gain and speaker placement), but the flat part, given inevitable room resonances. One can EQ out some of the affect of the peaks but dips are hard to deal with.
With only 2 woofers one has to chosoe whether 2 separate woofers to deal better acoustically with room issues, vrs doing one push-push woofer so as to gain the significant reduction in box panel load from the active force cancellation is a hard choice.
Personally i would chose 2 woofers with 15” drivers in them — actually i would 1st use 4 woofers with 2 x 10” in each. Sealed and use the EQ to move the response down if needed — same EQ as for helping with the peaks. Much easir to do wit DSP as it will have capability to move the time response to get the best response ou tof 4 woofers with different locations.
dave
I don’t have that now. With one. That’s more or less impossible. But I think I’ll be nearly there with 2.
And if not satisfied I’ll pull the 15s and replace with some 18s and pick a driver that will work in same enclosure size.
I can push about 110db I think with one. I’ll have to check
It’s pushing 1000w in a 140litre enclosure with around 25mm Xmax so my 15 beats a lot of 18s in some respects. But there is always better out there
To be honest I’m going to be experimenting with bigger woofer less Xmax as for music I’m needing more midbass and better integration.
Good point. 2 woofers in opposite locations should be a good starting point.
It’s all the nulls that really create problems. EQ can’t really sort cancellations. I have Dirac and it’s good but has limitations.
I’m flat to 20 apart from the huge 40 to 55hz 20db dip. Lol.. That’s what the second sub is for.
Sometimes it’s not about more output as much as it’s about making sure all frequencies within 2 db of each other. You need to be hearing everything equal and clean. Least amount of EQ boost possible.
Unless your wanting to literally bring the house down, 2 x 15 or 18 inch strategically placed with a room correction system such as Dirac or a mini dsp should make for a satisfying experience. Depending on taste and room size.
I can’t forget that some people like ridiculous amounts of bass. Or have huge rooms.
I haven’t heard a system in a house that could do what my JL audio could do on my car. Obviously a different environment.
If your after more output than finesse. Build a sealed 18 with big Xmax, shove it on a corner and give it 1500w. Should do ok.
Or build 2 and shove them in opposite corners and give them 1500 each. Best of both worlds