Hi,
I'm thinking to dedicate one room as amp building/modding and rehersal, and I had an idea on how to place a pair of speakers to hear music.
Imagine one corner of the room and place a single wooden board at 45° with gaskets on its sides: isn't it a TL with triangular shape and the lenght of the floor-to-ceiling height? Will it work?
If it works, with straight walls it would be quite simple to be built.
With 90° walls and 45° baffle, the section of the "cabinet" will be the baffle width squared and divided by 4.
Ceiling is 273 cm, that it's a quarter wavelenght of 31 Hz, so that should be the Fs of the speaker, correct?
Is there a full range, cheap speaker that can fit the requirements?
It will be something I would like to play with during the winter, to be able to build it in 2022.
Thank you in advance,
Kind Regards
I'm thinking to dedicate one room as amp building/modding and rehersal, and I had an idea on how to place a pair of speakers to hear music.
Imagine one corner of the room and place a single wooden board at 45° with gaskets on its sides: isn't it a TL with triangular shape and the lenght of the floor-to-ceiling height? Will it work?
If it works, with straight walls it would be quite simple to be built.
With 90° walls and 45° baffle, the section of the "cabinet" will be the baffle width squared and divided by 4.
Ceiling is 273 cm, that it's a quarter wavelenght of 31 Hz, so that should be the Fs of the speaker, correct?
Is there a full range, cheap speaker that can fit the requirements?
It will be something I would like to play with during the winter, to be able to build it in 2022.
Thank you in advance,
Kind Regards
If your transmission line is an open ended, straight pipe of constant cross-sectional area, you can use the classic equation, f = v / (4 x L)
L = length in metres
v = velocity of sound (344 m/s)
f = resonant frequency of driver in Hz
Inserting your L of 2.73 m does, indeed, give f = 31 Hz
L = length in metres
v = velocity of sound (344 m/s)
f = resonant frequency of driver in Hz
Inserting your L of 2.73 m does, indeed, give f = 31 Hz
Open ended/sealed at both ends = 1/2 WL resonator, so ~34400/2/273 = ~63 Hz Fp: Resonances of open air columns
Or leave a gap at the floor for 1/4 WL and adjust as required to tune it exactly to Fs empirically as the pioneers recommended, though only most beneficial if driven with a high impedance; otherwise tune to best overall in room response.
Or leave a gap at the floor for 1/4 WL and adjust as required to tune it exactly to Fs empirically as the pioneers recommended, though only most beneficial if driven with a high impedance; otherwise tune to best overall in room response.
Yes, if constructing a pipe with a single open end near the floor, shorten the length accordingly and calculate the new driver resonant frequency required, using my formula.
As GM says, you won't get the optimum result without tweaking, but it may be good enough for uncritical listening in your work/rehearsal room.
As GM says, you won't get the optimum result without tweaking, but it may be good enough for uncritical listening in your work/rehearsal room.
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That's very interesting, boswald: SOLO Eckbox | Visaton
Open at the top rather than the bottom - or so I imagine!
Open at the top rather than the bottom - or so I imagine!
Attachments
FWIW, I did quite a few of these simple corner horns for small rooms, dorms, apartments, using whichever end faced a ceiling or floor had no inhabitants or vented each end for when there was both and over time it turned out folks seem to prefer top vented, so have no doubt that's a major reason why the BIB horn has been so popular.
For sure, my best overall performing subs has been driver at floor, vent at ceiling.
For sure, my best overall performing subs has been driver at floor, vent at ceiling.
The Eckbox is closed, as the B200 has a higher Qts.
But depending on what driver you choose, you can do whatever it requires with this idea.
If you are willing to go multi-way, have a look at the Allison Three, mounted woofer at either floor or ceiling, it works quite well, in all but the tiniest rooms. It need not have a full box, if well fitted.
But depending on what driver you choose, you can do whatever it requires with this idea.
If you are willing to go multi-way, have a look at the Allison Three, mounted woofer at either floor or ceiling, it works quite well, in all but the tiniest rooms. It need not have a full box, if well fitted.
What range had it? What is the benefit of the vent at ceiling?
Boswald, I'd go for a fullrange, maybe with a big speaker (12-15").
What I've seen is that all mentioned speakers have wooden cabinet with no walls as part of it.
I'm trying to imagine how to shape a vertical horn that then becomes horizontal horn: use the full height of the room (horn up-down) for the first part of the horn plus a wall for the second part of an horizontal horn (horn left-right).
Sure. Load it in the corner for maximum gain. Sealed baffle has certainly been used… exactly as you describe.
dave
dave
Thanks AllenB!
I had to admit it took me a moment to understand it wasn't a Picasso's naked girl but the deflector at the ceiling, but now that I can see it, it's really nice and simple. I like it!
I had to admit it took me a moment to understand it wasn't a Picasso's naked girl but the deflector at the ceiling, but now that I can see it, it's really nice and simple. I like it!
Thanks Dave!
is it something you'd suggest to do, or too difficult to correctly seal baffle and walls around? Can it be done in drywall, or it is not still enough?
...can the corner between the walls and the ceiling used as well? I've bought a new house with a kitchen/livingroom area that is 12x4 meters, and I could use the upper corners for this kind of speakers. They will need to point at around 1 meter from the floor at 350mm from the wall, so approximately "loose" 173 cm in 350 cm, that should be pointing down 30°. Will it work, or better to keep the FHXL for that area?
OT:
is it possible to buy just the stuffing for the FH? I would like to be sure to use the right one!
During my active DIY audio 'career', recordings were mostly ~ -24 dB/40 Hz same as prosound with a few down to ~32 Hz, so this was the range for most with the last 'stereo' pair being ~16 Hz for a full range pipe organ CD.
The WLs are so long that at my fixed 120 Hz XO, the driver, vent, corner combo was basically an LF infinite array, so in the lower mids down to cutoff it came closest to a live concert's high pressure cocoon that for some of us is what goes a long ways towards making HIFI/HT a 'is it live or is it Memorex' front row seating experience that I was fortunate enough to be raised in.
Unfortunately, unless it's really large it will only deflect HF, so unless you want max amount of it to comb filter with the driver, don't recommend using it.
Better to make an inverted taper going all the way to the ceiling with triangulated notches on each side big enough to at least [crudely] maintain, if not actually continue, its flare factor [conical, expo/whatever], frequency [horn cutoff [Fc], i.e. normally don't want to audibly 'pinch' it; so for corner loading, design a full size horn and only use an 1/8th WL long 'slice' out of it or as much as your ceiling height, room volume [terminus/mouth] will allow.