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I dont know this wood, but In OB vibrations are small there is no box, I could use the cheapest or real wood if funds allow.
Vibration is definitely a factor in OB, as there is little to no bracing to dampen or break it up.My approach has been to separate the bass units from the midrange and tweeter. Easily done when using GR research OB bass.For the midrange/tweeter baffle, a sandwich construction can be a good idea.My baffle is made of steel, to which a 30 mm baltic birch board has been glued, with a 2 mm layer of non-hardening marine glue.The midrange drivers are mounted in the birch board, not the steel front baffle./The Priest
Anyone use, or considered using Panzerholz 'wood' for OB baffles? It seems to have amazing qualities that reduce the transmission of unwanted vibrations.
If I put my ear to the main baffle I can quite easily hear the mid range driver playing its music. My main baffle is 55mm void free birch.I guess this means the main baffle is vibrating along and will eventually re-emit those vibrations to fog the SQ. It may be less than a box but in the quest for ultimate SQ would contribute. I live by the saying that in sound quality, everything matters.Equally the 15" bass driver will be transferring its vibrations to the mid range driver. OB builders have chosen various alternatives to alleviate this effect which include the use of separate 'isolated' baffles for each driver and mounting drivers from their magnets. I was hoping to explore the option of a vibration 'free/adsorbing' baffle.
I have used Richlite to control speaker cabinet resonances, it works very well. Richlite is similar to Panzerholz, both use a phenolic resin with the Richlite having thinner layers. Richlite is made in Tacoma, WA.All sizes and thicknesses up to huge is available, as an example a 30" x 60" x 1" thick is $316.95. It also is available in 1/2" - 2" thick sheets. Sample sets are $35.https://richlite.com/Depending on your location you may find Richlite at eco-builders or high-end counter top suppliers.
Bear in mind that resonance and vibration are two distinct things. Although intertwined when it comes to loudspeakers, resonance is an aural thing and vibration is a mechanical one. One can certainly cause the other and nothing is immune... all things resonate at some frequency, the key with speakers is to keep it outside audible range. Vibrational energy cannot be "drained away" as I've seen written way to many times. It can be converted to some other form, heat being the most common, but not the only possibility. I didn't take away a lot from Science class, but do remember that energy is neither created or destroyed.Box resonance issues are certainly reduced with open baffle, but construction materials can still audibly resonate. Generally speaking, dense and, to some degree, flexible or malleable are good bets to mitigate unwanted resonance. I think we tend to think in terms of "more is better", and particularly in the audiophile arena, more money spent means better result. I don't know if Panzerholz would make a good open baffle construction material or not, but like many things it's not a panacea where "one size fits all" nor does it have magical properties that will make our lives better somehow. To me, that's where the theoretical discussions go off the rails.
This a prob, do you had used rubber rings tô install the drivers ?It cán be used felt rings also.
I am very much liking the qualities and price of this. Can you tell me how it machines and cuts. Many of these exotic materials rapidly dull power tools such as routers.
Richlite is hard...really hard. It will dull HSS quickly, carbide somewhat less fast. Just like anything else hard, cutting will reduce tool edge life...no free lunch. I have a 1" piece here I experimented with and it was surprisingly difficult to get through saw. Perhaps different tool geometry would work better, but I doubt it will ever cut "like butta".I imagine Panzerholz would be similar.
I use options of cork, felt and rubber rings on the drivers. On these vintage drivers they were often built in at time of manufacture. Here is the Altec 416 15" driver with cork gasket.