The TH18 is basically a 101dB/2.83V box. It's also 305 liters (net).
The ODTL design I provided is a 98dB/2.83V box that is 164 liters (net). So that makes it 2dB less sensitive, in a box that's just over half the size of the TH18. Hoffman's Law and all.
Efficiency at low frequencies is not only dependent on box size, but the "order" of the design. A 4th order BP occupying the same volume will have the same (or less) efficiency at low frequencies. A 6th order BP will be a little more efficient, but will also have a narrower bandwidth.
IMO bandpass boxes are decent if they're done right. Emphasis on "done right". ALL of the output of the box is through the vents, so cookie-cutter design techniques based on lumped-mass modeling are likely not going to cut it, because they don't take the driver's varying inductance (and its effect on the upper part of the passband. Then there's the question of ensuring that the vents are large enough to minimize compression effects, and choosing the best box geometry to minimize out of band vent resonance effects. They have be used correctly in a full-range system (cutoff frequency for the LP filter will be different compared to a vented box, because bandpass boxes already have a "built-in" LP filter). Then there's the question of what happens at high power with all of the heat generated by the driver trapped in the box.
Witness the "Enigma", a 4th order BP design I did many years ago. The result was "Ok", not exceptional. Well, I rebuilt the design a little last year (using FR tests and more advanced modeling techniques), and it sounds so much better. It's currently in use in my brother's bar, providing bass for the bar's background audio system. People like how it sounds, and it only took 15 years for me to get it right, LOL.
The FBT Pro MaxX 15sa looks like a decent design. And it's powered, not passive, which can be a plus. Note however that it's 5dB down at 50 Hz (based on the published FR chart), so that's somewhat stretching the term "subwoofer" a little
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(on the risk of derailing this thread)
Yup, confused me too.
As was the suggestion that the design relied on "non-linear behaviour". I've had that conversation before on the ROAR thread - why would anyone want to build a subwoofer (or **ANY** speaker for that matter) that relied on NON-linear behaviour at higher SPL levels for its performance? Does anyone actually want a speaker that sounds different, depending on how much SPL its producing? That's usually something we're trying to minimize or avoid in our designs.
In any case, the "directionality" of the ROAR (and the suggestion that this depends on SPL) can be easily be quantified by FR measurements at different angles and different SPL levels. Where are the measurements?
Anyway, not saying any more on this subject - I really don't want to derail the OP's thread.
according to Tune-Bot's chart, modern (near "square" bass drums in the 26" diameter might tune in the mid 40's for the batter head: tune-bot
I have a 26x14 Ludwig steel marching bass drum and that size is recommended (in marching work) to tune to A2 (55Hz) on the low end. With a heavy -thick head, I've seen RTA show 23Hz content for a brief while (in a very small room)
Death metal and other high speed double pedal work seems to have the kick drum tuned higher than the floor tom for intelligibility and timing "clicks" rather than thuds.
John Bonham's kick seemed tuned pretty high - that and good ol' four string bass guitars should lighten the PA stack load
I have a 26x14 Ludwig steel marching bass drum and that size is recommended (in marching work) to tune to A2 (55Hz) on the low end. With a heavy -thick head, I've seen RTA show 23Hz content for a brief while (in a very small room)
Death metal and other high speed double pedal work seems to have the kick drum tuned higher than the floor tom for intelligibility and timing "clicks" rather than thuds.
John Bonham's kick seemed tuned pretty high - that and good ol' four string bass guitars should lighten the PA stack load
Well, that's with roomgain etc. That SP level can easily be reached but I'm very sure you need a lot more than that.
That won't help you. That's very subjective and down to the person describing it. Unless you know the one describing the sound very well, the impressions you get from 'how does it sound' will vary vastly from your perception because, well, it's subjective and different how everyone feels and on top of that, the wording of the description will (mis?)lead you to the one or other side. So either you know the one very well, or the one discribes both things, which means the standards it becomes judged by and the wording and phrases are within the same dimensions. If they describe just one of them, take that with a pinch of salt. Not because they're lying but because the lack of comparability.
Well, what subs do you have now? I think that's a very important thing to know to suggest anything that's supposed to be better (or gives the reason why you have to EQ the sub that low).
No. THs produce various distortions, long decay times and a high group delay. That is resulting in psychoacoustic effects, long GD is sometimes percieved in going lower, 'fatter' but in acoustics there's no such thing as free lunch, in other words, they also sound 'muddier' at the same time. You also don't know the settings of the DSP with EQs, xo frequencies and filter characteristics and low cut.
The cubo got a peak at 60-70Hz, they are louder there, that's why they are percieved as 'deeper'. The Cubo and the Tham both got their own sound, the Tham more neutral (well, if you could use that word at all). If you like it, fine, go for it. If you want a clean reproduction, it's probably better to look for something else.
I like horns but what you are describing is definitely not a horn subwoofer. Your idea of the ideal subwoofer fits perfectly to a bunch of plain ported 18" subs. They are much smaller, so much better to handle and transport. In the space you put 2 cubos you can put 3-3,5 18" subs. These will have a lower group delay, will be able to be crossed over higher (if needed) and will sound cleaner. It's always better to get more membrane surface and have more headroom, your subs will live much longer and sound better, remember, there's a thing called power compression.
Yes, ofcourse, because you were comparing just one sub. It looks impressive if you compare a TH with a single BR sub. Compare 2 Cubos with i.e. 3 BR ones and you'll notice the Cubos aren't that impressive anymore. And if you realize you can get 3-4 Thomann The Box 18/500 drivers for the price of a single 18HP1060, the Cubos become outperformed in every single discipline.
Yeah it’s a shame the ROAR are so big otherwise that would be interesting.
Ah I haven’t the FR chart for the FBT, I’ll forget that idea then.
Freddi: yeah that’s about what I thought to be honest. I don’t think the fact I’m having to boost 35hz drastically has anything to do with the tuning and fundamental of my drummers kick drum. Although I wish he would get rid of his kick port and go back to using a front head without a whole, made my life much easier, sounded so much better.. I think it’s down to my subs not moving enough air to achieve the sound I would like..
What if I give you an idea that might help everyone understand my goals a little more..
There’s a PA company that gets called in to do a lot of the bigger festivals I play at, I see them 10+ times a year , they use 2 QSC KW181s per side and 2 KLA12s per side, with 2 K12s as centre fills.. now the rooms the festivals are held in are massive, they are literally arenas, on place especially could hold 10k, the might not be full 2,000 people maximum, likely less.. but that’s all they use, and talking to the engineer last year, that’s all they have!! . Now personally I would say there massively underpowered and nowhere near enough boxes for that kind of job, but they do it fine.. personally I don’t like the sound of QSC KW181, I find it lacks and real definition and punch.. I’m not feeling the kick drum In my chest as I walk past the font of the stage. Though that could be down to the engineer more than the speakers.
So for big gigs the PA is normally supplied and for little gigs I don’t take subs there’s just no need.. I need something for venues ranging between 150 to 800 people max.. and I know that a kw181 can do that size ok, so I’m looking for something with the same kind of output as a kw181 Or better preferably.. I don’t really care what size speaker it is as long and I can get a good deep thud in the chest at least halfway down a large room.
I’ve considered 2x12 or 2x15 BR ... a single 18 either hornloaded or other. As long as I can get 40hz to 90hz at a good SPL, then I’ll be happy...I’m not too overly concerned how musical the box sounds because 90% of the time it will only be used for kick drum and quite music playback before and after gigs... I tend to highpass the bassist at 80hz sometimes higher anyway because it becomes overwhelming.
The power amp I’m thinking of using is 1200w RMS @ 4ohm .. per speaker, it’s all I can afford right now, so as much output as I can get out of a box with that kind of amp power, hence the horn loaded idea.
And like I said my maximum size limit is 24” W 25” D 40”H.. I also don’t mind useing several smaller boxes like several 12”.
????
Sorry I know I’m asking the impossible really but I’m really suck with size / weight at the moment, in the future if it’s not so much of an issue I’d have several TH18s per side and be very happy.
Ah I haven’t the FR chart for the FBT, I’ll forget that idea then.
Freddi: yeah that’s about what I thought to be honest. I don’t think the fact I’m having to boost 35hz drastically has anything to do with the tuning and fundamental of my drummers kick drum. Although I wish he would get rid of his kick port and go back to using a front head without a whole, made my life much easier, sounded so much better.. I think it’s down to my subs not moving enough air to achieve the sound I would like..
What if I give you an idea that might help everyone understand my goals a little more..
There’s a PA company that gets called in to do a lot of the bigger festivals I play at, I see them 10+ times a year , they use 2 QSC KW181s per side and 2 KLA12s per side, with 2 K12s as centre fills.. now the rooms the festivals are held in are massive, they are literally arenas, on place especially could hold 10k, the might not be full 2,000 people maximum, likely less.. but that’s all they use, and talking to the engineer last year, that’s all they have!! . Now personally I would say there massively underpowered and nowhere near enough boxes for that kind of job, but they do it fine.. personally I don’t like the sound of QSC KW181, I find it lacks and real definition and punch.. I’m not feeling the kick drum In my chest as I walk past the font of the stage. Though that could be down to the engineer more than the speakers.
So for big gigs the PA is normally supplied and for little gigs I don’t take subs there’s just no need.. I need something for venues ranging between 150 to 800 people max.. and I know that a kw181 can do that size ok, so I’m looking for something with the same kind of output as a kw181 Or better preferably.. I don’t really care what size speaker it is as long and I can get a good deep thud in the chest at least halfway down a large room.
I’ve considered 2x12 or 2x15 BR ... a single 18 either hornloaded or other. As long as I can get 40hz to 90hz at a good SPL, then I’ll be happy...I’m not too overly concerned how musical the box sounds because 90% of the time it will only be used for kick drum and quite music playback before and after gigs... I tend to highpass the bassist at 80hz sometimes higher anyway because it becomes overwhelming.
The power amp I’m thinking of using is 1200w RMS @ 4ohm .. per speaker, it’s all I can afford right now, so as much output as I can get out of a box with that kind of amp power, hence the horn loaded idea.
And like I said my maximum size limit is 24” W 25” D 40”H.. I also don’t mind useing several smaller boxes like several 12”.
????
Sorry I know I’m asking the impossible really but I’m really suck with size / weight at the moment, in the future if it’s not so much of an issue I’d have several TH18s per side and be very happy.
Okay, that explains everything.
If you are talking about the Blackline X115 or SXF115.. Yes and no. They will both sound cleaner but they are not tuned deep enough, they are made for high spl. So they will reach the spl of the tham 18 but they are not going low enough. Also, they are expensive.
in what way? because of their shape the Martin's waste truck pack space, low frequency(?) a Martin single 15 has a low frequency cutoff of 70hz in a stack of three you get to roughly 60hz but from there up to 250 hz you get usable spl the MkIII two 15 is different but far larger.
Yes, it shows they go deeper and reach the same spl. You need more power though.
here's a little something (sorry if this seems to confound this issue at hand "compact efficient subs")
but to me is a key issue with respect to "chest thumping kick sound"
Tech Talk: Building Directional Subwoofer Arrays - ProSoundWeb
but to me is a key issue with respect to "chest thumping kick sound"
Tech Talk: Building Directional Subwoofer Arrays - ProSoundWeb
You probably don't know the placement of the subwoofers is much more important than how much max spl etc it can produce. Please watch this video:
YouTube
Edit: That works also on lower number of subs.
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