Do you think you could optimise the waveguide for impedance loading the tweeter, and trade off some of the dispersive capabilities in the high end to get a non-CD or more narrow CD, with higher max SPL? BTW, what is the sensitivity of the prototype?
there are many ways to trade off but still maintain CD or at least slowly changing directivity. The extremely wide beam at HF comes at the expense of lowered on axis sensitivity. the same energy is spread wider. Conversely, at the low end the WG narrows the beam and this amplified on axis. The bottom line is that with the computerised shape optimisation the desired trade off can be reached systematically. the flip side is that there is really no one size fits all solution l.
😎
/jk - I know you said tricky, not impossible.
I like the shoutout to VCAD in the whitepaper. Noticing a few companies now marketing the use of "high end computer modelling" in their speaker creations, when its clearly VituixCAD 2. Amazing software once you've got the hang of it.
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Business idea, make it a purchasable software and DIYers would empty their wallets 😉
But maybe that would also help the competition too much 🤔
COMSOL is still cheaper than Klippel NFS. However, it takes 3-4 years to learn COMSOL which is the biggest investment.
3-4 years for you, so even more for most of us 🤣
the coupled 3D - 2D simulation was quite a challenge to set up so that initially restricted the shape to axisym. My plan is to proceed with an elliptic or maybe super elliptic WG using the same technique . That would also be more flexible for choice of CTC and baffle dimensions etc. I have done elliptic WH before for 2pi and a 3rd orth tweeter (will be embedded into a commercial product from a customer of ours)
Now that the technologies for Purifi drivers have been granted patents and the driver lineup been been renamed Ushindi, is there a future plan for a lower cost line-up?
Polymer or stamped steel baskets, more basic motors, polypropylene cones, but retaining perhaps the game changing funky surround?
Polymer or stamped steel baskets, more basic motors, polypropylene cones, but retaining perhaps the game changing funky surround?
Or those of us who just want to play loud. Isn't the Purifi woofer like 84 dB? That means humongous amplification to really blast things. I'd like to see these principles applied to higher sensitivity applications.
I don't think a rework of what is shown here would get so much more SPL just by narrowing directivity, likely a new thing would be needed, maybe these principles incorporated into a compression driver?
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I was thinking more along the lines of lower distortion at the xover point, but I'm assuming the ptt1.3 is going to be more than capable, even in the 1-2kHz cross range.
New PTT10.0X preview data sheet online
https://ptt.purifi-audio.com/shop/p...,6022,6023,6024,6025,6026,6027,6028,6029,6030
https://ptt.purifi-audio.com/shop/p...,6022,6023,6024,6025,6026,6027,6028,6029,6030