This is an important question. Absorbtion works best for frequencies with maximum 4 times the wavelength of the thickness of the absorbing material. Since the main concern is to dampen standing waves, which are minimum twice the largest dimension of the enclosure, your layer of absorbing material needs to be quite thick.
A thin layer will not work, longer wavelengths, of the order of the standing waves that may occur in an enclosure, will not be dampened by it.
So if i want to damp around 100hz, as there is a bump in freqresponse i would need to deal with 3.43m long wave, and much thicker layers of dampening. I dont see that happening
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vacuphile said:
I do not know much about tube amplifiers, but I'm fairly certain that "modern amps" are mostly solid-state, and achieve their highest reliability and subjective sound quality at lower power levels. I may be wrong but I think I'm right.
vacuphile said:
Any damping that's added is only expected to clean up the unwanted mid-range reflections within the enclosure. If the damping were to absorb all the bass, there wouldn't be much of a "bass reflex" speaker left after damping !
When it comes to bass reflection, I think one needs to worry more about the room acoustics than the ones within the cabinet, as the latter is predictable (and necessary), while the former is a function of a hundred variables.
Thats the thing, i dont know much about it, is the layout i drawn ok ? If so il go with it, its the "easiest" layout so far
Correct, or to contain insulation, the reason I suggested/recommended it. IOW, why cover a 'blanket' of insulation when all you need do is cover the components?
Also, FWIW I found that taking a 'page' from Bozak's Concert Grand speaker's damping design, 'hanging' a 'blanket' from the top, parallel with the baffle and letting it 'flap in the breeze' is a great solution.
Correct, or to contain insulation, the reason I suggested/recommended it. IOW, why cover a 'blanket' of insulation when all you need do is cover the components?
Also, FWIW I found that taking a 'page' from Bozak's Concert Grand speaker's damping design, 'hanging' a 'blanket' from the top, parallel with the baffle and letting it 'flap in the breeze' is a great solution.
True, but i want to prevent said insulation leak from bass reflex hole into the room and air
. In that speaker with horn you linked kinda makes sense, but i will have just some insulation in size of woofer around it. For array alu tube, thats a different story, but it will be sealed anyway.
OK, cover the vent then.
FWIW, I never heard of any issues with insulation dust being pumped out of the vent until I got on the audio BBs in late '96, but I've nearly always critically damped them with less porous materials tightly stretched over them, so with my sub's reflex vents being a removable panel, had a look-see and if there was any buildup it was too fine/too embedded in it to tell there was any, so TTBOMK it's 'much ado about nothing'.
That said, any down firing I've done, the insulation was contained in a cheesecloth 'ball'/'bag' suspended from the top and since I keep forgetting yours is down firing, recommend you do the same in lieu of any panel mounting.
FWIW, I never heard of any issues with insulation dust being pumped out of the vent until I got on the audio BBs in late '96, but I've nearly always critically damped them with less porous materials tightly stretched over them, so with my sub's reflex vents being a removable panel, had a look-see and if there was any buildup it was too fine/too embedded in it to tell there was any, so TTBOMK it's 'much ado about nothing'.
That said, any down firing I've done, the insulation was contained in a cheesecloth 'ball'/'bag' suspended from the top and since I keep forgetting yours is down firing
, recommend you do the same in lieu of any panel mounting.
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OK, cover the vent then.
FWIW, I never heard of any issues with insulation dust being pumped out of the vent until I got on the audio BBs in late '96, but I've nearly always critically damped them with less porous materials tightly stretched over them, so with my sub's reflex vents being a removable panel, had a look-see and if there was any buildup it was too fine/too embedded in it to tell there was any, so TTBOMK it's 'much ado about nothing'.
That said, any down firing I've done, the insulation was contained in a cheesecloth 'ball'/'bag' suspended from the top and since I keep forgetting yours is down firing
When you say suspended, i think of rolling bunch of glasswool and wrap it around. I bought some gaze, which has less denser holes, but still will hold insulation. I tie one end and other, and there i leave a a bit to be hang, somewhere in middle parallel with woofer. Im thinking of just rolling bunch of gaze and gluing it to the top board of cabinet. Kinda like a giant pendulum inside cabinet
Whatever works! ) I kept the XOs in a separate box to have easy access for tweaks and/or outright replacement with the speaker leads permanently attached at the driver, XO and at the amp to limit the number of connections to just the one.
I think the diagonal inductor maybe kept straight (45* to right side) without any problems. Its flux lines don't cross those from others anyway. The distances look OK.
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Here is the top board, i will do damp pendulum tomorrow, i will go with around 500x500mm or less depending on wool cut. Thickness is 50mm, and i have 300mm backspace.
Im thinking to sandwitch two cuts and wrap it with cheesecloth, you can see density, it will hold it nice.
I also finally found someone to cut alu profile. I borrowed a jigsaw tool from uncle, but that thing vibrates like hell and stroke is as same if not bigger then 40mm, which is depth of profile. Impossible mission if you want precises cut.
Im thinking to sandwitch two cuts and wrap it with cheesecloth, you can see density, it will hold it nice.
I also finally found someone to cut alu profile. I borrowed a jigsaw tool from uncle, but that thing vibrates like hell and stroke is as same if not bigger then 40mm, which is depth of profile. Impossible mission if you want precises cut.
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Hey guys, i found some speakerwires 2.5mm, will this be ok ? I have around 16-18m in total, so i can run 4.5m for both speakers.
Also bought this glasswool, since it was sunday, my options were limited
Alu profile is cut, really nice job they did, i left it at my friend to polish it up and remove scratches markings..
Also bought this glasswool, since it was sunday, my options were limited
Alu profile is cut, really nice job they did, i left it at my friend to polish it up and remove scratches markings..
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