Sorry, I haven't had much love for PE lately and their site has taken all the joy out of shopping at PE. I am also spoiled, I can go see Meniscus on my lunch break.
PETT traffic is way way down. Remember the days when threads would scroll off page 1 in 4-5 hours? Now the 1st page shows threads from 3 days ago. We tried to warn them, but they've got a peculiar problem with any web design feedback. Life goes on!
But Chahly - Stahkist don't want speakers that look good, Stahkist wants speakers that sound good!
@rjj45 said:
PETT traffic is way way down. Remember the days when threads would scroll off page 1 in 4-5 hours? Now the 1st page shows threads from 3 days ago. We tried to warn them, but they've got a peculiar problem with any web design feedback. Life goes on!
They will either wise up and make the needed changes, or go the way of the Dodo. Don't recall ordering a single thing since they messed up their site.
Well, they do (still) have one of the slowest servers in the Midwest. I think the business model has changed in the past 10 years. That they highlighted a speaker design using an off-the-shelf crossover in a last sales flyer tells me a lot.
This sim was for a rectangular flat open baffle. Might be fun to see what an H-frame does. Generally I prefer the flat baffle to get away from the cavity resonances and have move flexibility in the x-o point.
@jhollander said:
This sim was for a rectangular flat open baffle. Might be fun to see what an H-frame does. Generally I prefer the flat baffle to get away from the cavity resonances and have move flexibility in the x-o point.
Would a U frame be a sufficient compromise between the Flat baffle and H-Baffle, goes lower than flat with hopefully lower cavity resonances?
Thanks Craig and John. When I am comparing for resonance in the graphs, its the blue squiggles? What is the yellow squiggle - did not understand Equiv circular baffle with omni source.
The cavity resonance must be calculated based on the cavity dimensions. It is not shown on any of those graphs. The blue trace is the predicted dipole response. You add that to the driver's IEC response, like you would add a diffraction response model.
John's models are top to bottom: 24" H frame, 12" U frame, 24" U frame.
Notice how the response of the 24" H frame and the 12" U frame are identical? Both show 100 dB at 30 Hz at xmax. Their dipole peak is at 200 Hz, so you can low pass them at 200 Hz and maintain constant directivity.
The 24" U frame, by contrast, can hit 100 dB at 25 Hz at xmax. However its dipole peak is only at 100 Hz meaning a lower crossover point.
In John's first sim a few posts up, the 24" wide flat baffle can has an even higher dipole peak (~300 Hz) but gives up another 5 Hz of bass extension.
None of this takes into account the cavity resonance which may or may not force an even lower crossover point.
Comments
how do you even find the deal of the day?
Does it matter?
Yes, sometimes it does...
Sorry, I haven't had much love for PE lately and their site has taken all the joy out of shopping at PE. I am also spoiled, I can go see Meniscus on my lunch break.
I have not even perused PE's site since the change, and I had a list waiting to hit 'buy'. POOF! gone.
InDIYana Event Website
Yep, not a fan of the new site. Wonder if their sales show the love?
PETT traffic is way way down. Remember the days when threads would scroll off page 1 in 4-5 hours? Now the 1st page shows threads from 3 days ago. We tried to warn them, but they've got a peculiar problem with any web design feedback. Life goes on!
They will either wise up and make the needed changes, or go the way of the Dodo. Don't recall ordering a single thing since they messed up their site.
It's now called the "Daily Deal" and it's in a teal colored banner about a 1/3 of the way down on the front page.
I still buy from them, don't see what the big fuss is about. Things change.
Well, they do (still) have one of the slowest servers in the Midwest. I think the business model has changed in the past 10 years. That they highlighted a speaker design using an off-the-shelf crossover in a last sales flyer tells me a lot.
Speaking of off the shelf crossovers...
...and OFFER EXPIRED before 8:30 AM. But when you go to the product page there are 142 in stock still listed at the special price. WTF?!?
They're just F'in with us now.
I think so, Tom.
Dotd. Might work open baffle. Or for pro use. Models well in a isobaric 10cf box tuned to 20 hz. (But at that point there are better choices.)
https://www.parts-express.com/Peerless-FSL-1830R06-08-18-Professional-Paper-Cone-Subwoofer-8-Ohm-264-1482
Hey John Hollander, how does that 264-1482 model in ABCDipole on a 24" wide flat baffle?
It doesn't have the prettiest backside, does it?
Not bad 100 dB 2pi at 35 Hz.
U Frame? H Frame? Does ABC baffle calculate for OB?
Super tempting for OB design, but jeez, my shelves are overflowing as it is....
This sim was for a rectangular flat open baffle. Might be fun to see what an H-frame does. Generally I prefer the flat baffle to get away from the cavity resonances and have move flexibility in the x-o point.
Would a U frame be a sufficient compromise between the Flat baffle and H-Baffle, goes lower than flat with hopefully lower cavity resonances?
H frame would have less cavity resonance as half the wing depth is in front and the other half is in back.
I had good results with a pair of beyma 12BR70's in a modified H frame (3 way with coaxial)
Craig's right the H frame is a better compromise. U frame gives the best bass loading in the same depth at the sacrifice of the cavity resonance.
H frame with 24 inch depth, U frame with 24 inch depth and 12 inch depth
Thanks Craig and John. When I am comparing for resonance in the graphs, its the blue squiggles? What is the yellow squiggle - did not understand Equiv circular baffle with omni source.
The cavity resonance must be calculated based on the cavity dimensions. It is not shown on any of those graphs. The blue trace is the predicted dipole response. You add that to the driver's IEC response, like you would add a diffraction response model.
John's models are top to bottom: 24" H frame, 12" U frame, 24" U frame.
Notice how the response of the 24" H frame and the 12" U frame are identical? Both show 100 dB at 30 Hz at xmax. Their dipole peak is at 200 Hz, so you can low pass them at 200 Hz and maintain constant directivity.
The 24" U frame, by contrast, can hit 100 dB at 25 Hz at xmax. However its dipole peak is only at 100 Hz meaning a lower crossover point.
In John's first sim a few posts up, the 24" wide flat baffle can has an even higher dipole peak (~300 Hz) but gives up another 5 Hz of bass extension.
None of this takes into account the cavity resonance which may or may not force an even lower crossover point.
Thanks Craig - found the dipole peak frequencies and the 100 DB points.
For the cavity resonance, is it measurable or how do you find it and fix it?