Ok. Say I attached a string to the middle of the panel, pulled it straight out then let it go. In this mode, the panel will resonate in and out until it is damped.
This is a default mode and it figures into the transient response of the panel. It is activated by various actions.. not the least of which where the box is blown up like a balloon at lower frequencies. This happens over a wider band, but energy tends to migrate toward the natural resonance frequency.
This is a default mode and it figures into the transient response of the panel. It is activated by various actions.. not the least of which where the box is blown up like a balloon at lower frequencies. This happens over a wider band, but energy tends to migrate toward the natural resonance frequency.
But a bending panel resonance depends on stiffness, dimensions, weigth, inner damping and suspension "holding" structure and not (so much) on sound propagation in the panel itself - if I am not completely wrong...
@AllenB @stv Yes, 100% agree. Consider AllenB experiment using a 1m panel. Once you let go the string, it will oscillate at its resonance frequency. The wavelength of that oscillation will be 2m. With the speed of sound somewhere around 3...5 km/s (typical number for wood, corresponding to stiffness and density), the resonance frequency will be around 1.5...2.5 kHz. Yes, there will be damping and "smearing" of the oscillation, but the basic argument of post 1745 is still valid.
If you want to see the speed of sound in action for that mode, suspend a large sheet of plywood by the edges and broadband activate it with an impulse by shooting a high speed projectile at the middle of it while watching with a high frame rate camera. You'll see the ripples like a pebble in a pond.
However walk up to it and push the middle in with your finger and it bends cleanly. The high speed of sound actually helps a lower frequency resonance act as a simple lumped parameter affair. The mass of the panel and it's compliance, but the speed of sound in the panel doesn't get involved per se.
However walk up to it and push the middle in with your finger and it bends cleanly. The high speed of sound actually helps a lower frequency resonance act as a simple lumped parameter affair. The mass of the panel and it's compliance, but the speed of sound in the panel doesn't get involved per se.
@AllenB It seems you're referring to the propagation of an impulse on a very large 2D surface (one where the fixed edges are so far away that there won't be any meaningful resonance). Something like this:
This has nothing to do with the resonance of a finite-size panel of a loudspeaker box, as considered in my previous comments. I don't think the propagation of the ripple wave on very large panel (or a pond) helps with improving the bracing or damping the OSMC box in any way, but please feel free to start a new thread if you think it's worth it (and let us know about it).
This has nothing to do with the resonance of a finite-size panel of a loudspeaker box, as considered in my previous comments. I don't think the propagation of the ripple wave on very large panel (or a pond) helps with improving the bracing or damping the OSMC box in any way, but please feel free to start a new thread if you think it's worth it (and let us know about it).
My crossover parts have arrived, it was nearly £2k including some extra stuff not included in the parts list which I have attached for reference. It will be a few months before I can comment on the sound.
Beautiful. Look forward to seeing them come together!
Happy Friday -
Happy Friday -
Very cool! Have fun and can’t wait to see your progress!
Wow I didn't think the crossover parts would be that expensive - @maximax77 Did you use "audiophile" capacitors, etc? I think I am correct in understanding that you that there can be a wide price range for the equivalent value capacitor
One can pay much more for crossover parts, take a look prices for duelund cast capacitors and inductors. I included the parts list so that people can compare with the recommended list in the OSMC doc. However, the price estimate there is now way too low and it would still have come to lower 4-figure if I had chosen those parts. Many part numbers on the doc are now outdated but similar parts are obviously available.
I just hope noone goes down this path with the OSMC. Please!
Would you mind pointing out the details? You could submit an "issue" at https://github.com/mbrennwa/osmcdoc
No, not at all. I just think the cost/benefit ratio of the Duelund stuff is a wee bit off.
Haven’t tried them so can’t comment. But not sure which of the commercial manufacturers are even using them or equivalent.
Alright, this is a copy/paste from duelundaudio website:
"Duelund inductors offer many advantages over conventional coils, such as:
What low inductance? Does that mean they can't deliver the desired inductance value?
🙂
"Duelund inductors offer many advantages over conventional coils, such as:
- Superior sound quality: Duelund inductors feature very low resistance, low inductance, and low distortion, which means they can deliver a clear, natural, and dynamic sound with minimal loss or interference." End of quote.
What low inductance? Does that mean they can't deliver the desired inductance value?
🙂
Hint: I find that highlighting the 'meat' of a query and 'Googling' takes me right to it.