There is brands out there suggesting a 8" woofer as better from the basic version due it aluminum reinforced basket.
And my question is what is the criteria for a woofer so to need reinforced basket?
It supposed that the advantage is elimination of resonance, but from the other hand, one 8" woofer at 70 to 90W I do not know how prone it is regarding resonance effect?
And my question is what is the criteria for a woofer so to need reinforced basket?
It supposed that the advantage is elimination of resonance, but from the other hand, one 8" woofer at 70 to 90W I do not know how prone it is regarding resonance effect?
Basket resonance can be a source of coloration, specially with thin stamped frames. If you knuckle the frame of such a woofer you will hear a distinct ringing sound. Applying rope caulk of something similar material to the frame can dampen those resonances, you can find lots of tips on Google...
Equally important is the reflection caused by those types of frames -especially the ones with small openings - restricting free air flow from the back of the driver, and reflecting air waves back to the cone. What you can do there, is to glue small felt pads (3-4 mm thick, cut to the shape of the supporting part) to the INSIDE of the supporting parts of the frame, those can reduce,- but not completely eliminate- the effect.
Reinforced cast frame basket are less prone to these kinds of problems, but of course they cost significantly more.
Equally important is the reflection caused by those types of frames -especially the ones with small openings - restricting free air flow from the back of the driver, and reflecting air waves back to the cone. What you can do there, is to glue small felt pads (3-4 mm thick, cut to the shape of the supporting part) to the INSIDE of the supporting parts of the frame, those can reduce,- but not completely eliminate- the effect.
Reinforced cast frame basket are less prone to these kinds of problems, but of course they cost significantly more.
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Would you consider this pictured woofer that has ideal design as a metallic common type?
To be honest, my woofers needs new foam surrounds, but I am making second thoughts of getting something more wiser designed.
From the other hand this is a Philips made in Belgium and today things are different with all this manufacturing in Asia.
And I have nothing against Asia, but it supposed that engineering makes the difference in sound and I have doubts that generic woofers could have the a wider bass response as this speaker does.
Basically my woofer is designed for operation in sealed cabinets, and even if I look for replacement in the specifications it is not mentioned if a specific woofer is designed for open or sealed cabinets.
To be honest, my woofers needs new foam surrounds, but I am making second thoughts of getting something more wiser designed.
From the other hand this is a Philips made in Belgium and today things are different with all this manufacturing in Asia.
And I have nothing against Asia, but it supposed that engineering makes the difference in sound and I have doubts that generic woofers could have the a wider bass response as this speaker does.
Basically my woofer is designed for operation in sealed cabinets, and even if I look for replacement in the specifications it is not mentioned if a specific woofer is designed for open or sealed cabinets.
Attachments
Damp the fundamental
I think a possibility exists to damp the fundamental resonance acting in way assimetrico and casual pseudo with some type of damping action on the basket
I think a possibility exists to damp the fundamental resonance acting in way assimetrico and casual pseudo with some type of damping action on the basket
Couldn't find any data on that particular Philips woofer, but by the size of the magnet I would suggest a closed box of about 20-30 liters. It is very likely a highish Qts design with low Fs, so it is well suited for sealed boxes. Yes it is your typical "cheap stamped frame", so it could benefit from damping and applying absorbing pads.
Kiriakos,
very wise decisions about the Philips drivers. they are almost irreplaceable. usually very high sensitivity and good quality sound (paper cones, coils and magnets).
if you want leave them behind, I suppose they are working, and design or choose a new speaker for DIY. State your objectives like vintage look or sound, sealed, size of frame/cone, 2 or 3WAY and internal volume or dimensions (int. or ext.) for the interested speaker application.
very wise decisions about the Philips drivers. they are almost irreplaceable. usually very high sensitivity and good quality sound (paper cones, coils and magnets).
if you want leave them behind, I suppose they are working, and design or choose a new speaker for DIY. State your objectives like vintage look or sound, sealed, size of frame/cone, 2 or 3WAY and internal volume or dimensions (int. or ext.) for the interested speaker application.
applying absorbing pads.
I think both possible also to apply an arm to stop the magnet that are an oscillating mass .
Perhaps also a shaped plan can be adopted .
I could be is very difficult discover woofer resonance for by theoretical only a measure in a closed box with an accelerometer climbed on on one of the arms.
System is a mass coil and damper but too coplex to define . To change resonance, perhaps is possible attach by glue
a varius mass on arms of the basket
I think both possible also to apply an arm to stop the magnet that are an oscillating mass .
Perhaps also a shaped plan can be adopted .
I could be is very difficult discover woofer resonance for by theoretical only a measure in a closed box with an accelerometer climbed on on one of the arms.
System is a mass coil and damper but too coplex to define . To change resonance, perhaps is possible attach by glue
a varius mass on arms of the basket
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