The 8" SF are here and looked at some sims. I don't see going larger than 22L - 23L.
http://www.madisoundspeakerstore.com/approx-8-woofers/silver-flute-w20rc38-08-8-wool-cone/
I'd like to stick with the Penguin style box, using 5/8" thick ply for the dual vents.
http://www.madisoundspeakerstore.com/approx-8-woofers/silver-flute-w20rc38-08-8-wool-cone/
I'd like to stick with the Penguin style box, using 5/8" thick ply for the dual vents.
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That Silver Flute vented 8" bass cone looks very nice, ODougbo! 
A decision for you is going to be whether to wall mount it (ie Bookshelf), or freestand it with a bigger bafflestep coil away from the wall.
Looks like you just put a gentle notch at 4kHz and the slope is ideal for a simple crossover around 2.5 to 3kHz.
There's something you must know about the 8" woofer, 1" tweeter combination though. On a flat baffle you can get it phase aligned at crossover, but no better. With a bit of time alignment, you can get the phase alignment pretty much as good as you like across the 1kHz to 10kHz range. Being able to recess the tweeter between 3-6cms (more bafflestep needs more recessing) is just ideal, and your Penguin design seems able to accommodate this.
8" woofers also are rather loud, and it can be a struggle to get the tweeter loud enough, especially with the more efficient bookshelf designs.
Hope that helps.
A decision for you is going to be whether to wall mount it (ie Bookshelf), or freestand it with a bigger bafflestep coil away from the wall.
Looks like you just put a gentle notch at 4kHz and the slope is ideal for a simple crossover around 2.5 to 3kHz.
There's something you must know about the 8" woofer, 1" tweeter combination though. On a flat baffle you can get it phase aligned at crossover, but no better. With a bit of time alignment, you can get the phase alignment pretty much as good as you like across the 1kHz to 10kHz range. Being able to recess the tweeter between 3-6cms (more bafflestep needs more recessing) is just ideal, and your Penguin design seems able to accommodate this.
8" woofers also are rather loud, and it can be a struggle to get the tweeter loud enough, especially with the more efficient bookshelf designs.
Hope that helps.
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Power to the Penguin
Thanks Steve, again very happy with the manufacturing of SF woofer (I'm sure the price will jump eventually). They look like "shallow" throw drivers (8" xmax is 5mm), which is suited nicely for the front port idea.
Free Standing. But will move closer as necessary in to wall to increase bass.
I have a stash of the old MDT28/30: 91db, 8ohm, same as woofer, which should be a nice change. I'll start there but willing to try others. I will miss the lightness of the Vifa X25. I'm curious if the newer Morels have better top end than the old generation.
Power to the Penguins! I have a flat pack of scrap wood at the ready, to build test box: 1,375cubic inch, tuned at 50hz. They are easy to build; will take some photos to show the 3 places that need need a fine fit, other than that, router trimming, etc.
xo and xo's point...2,000 - 2,500
Thanks Steve, again very happy with the manufacturing of SF woofer (I'm sure the price will jump eventually). They look like "shallow" throw drivers (8" xmax is 5mm), which is suited nicely for the front port idea.
Free Standing. But will move closer as necessary in to wall to increase bass.
I have a stash of the old MDT28/30: 91db, 8ohm, same as woofer, which should be a nice change. I'll start there but willing to try others. I will miss the lightness of the Vifa X25. I'm curious if the newer Morels have better top end than the old generation.
Power to the Penguins! I have a flat pack of scrap wood at the ready, to build test box: 1,375cubic inch, tuned at 50hz. They are easy to build; will take some photos to show the 3 places that need need a fine fit, other than that, router trimming, etc.
xo and xo's point...2,000 - 2,500
As mentioned in PM, here's the circuit that fixes the phase problems on the 8 ohm Silver Flute vented Woofer on a flat baffle. The 4kHz tank mainly fixes Phase. Sadly it doesn't work with the 4 ohm version.
It needs a special and EFFICIENT +90dB tweeter to make it work, and I had luck with a TW70 and KE25SC by Visaton. Maybe your Morels. Really don't know. You need a tweeter that dips into a saddle below 4.5kHz. This is a surprisingly high 3.5kHz crossover. Long live the Penguin.
It needs a special and EFFICIENT +90dB tweeter to make it work, and I had luck with a TW70 and KE25SC by Visaton. Maybe your Morels. Really don't know. You need a tweeter that dips into a saddle below 4.5kHz. This is a surprisingly high 3.5kHz crossover. Long live the Penguin.
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Thanks for the help with the xo, not my forte
As you see a Morel ~ but placed it high the "tab" can be cut flush with top of cab.
Test box tuned at 40hz, but lots of materiel to trim/cut down (vent strips x 4).
New Pic - Looks the same as the 6.5 woofer, but this is the new 8" in a 1400 cubic inch box.
As you see a Morel ~ but placed it high the "tab" can be cut flush with top of cab.
Test box tuned at 40hz, but lots of materiel to trim/cut down (vent strips x 4).
New Pic - Looks the same as the 6.5 woofer, but this is the new 8" in a 1400 cubic inch box.
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Beware bargains, ODougbo. That's a 4 ohm version of the Morel MDT-30S. It might get tricky on crossover and impedance. Not saying it can't be done, but adds a layer of complexity.
Some very interesting designs to groove over at Tetra Speakers. They use SEAS and Morel which are the "Rolls-Royce" of drivers, IMO. I got there while investigating Tetrahedral designs...
An externally hosted image should be here but it was not working when we last tested it.
Well, why not?
New tweeter pic - going to try a ScanSpeak D2606/92200. The Madisound Speaker Store
Which I just realized looks like a Vifa D27TG that I bought years ago, and never found a home for them, I hope they improved them
On a side note, I'm finding its a whole lot safer to set speakers drivers in, from outside-in with scrap wood, vs. cutting a hole and using a typical 3/8" - 1/2" rabbit bit.
Which I just realized looks like a Vifa D27TG that I bought years ago, and never found a home for them, I hope they improved them
On a side note, I'm finding its a whole lot safer to set speakers drivers in, from outside-in with scrap wood, vs. cutting a hole and using a typical 3/8" - 1/2" rabbit bit.
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Results? Well good I thought the bass would rattle floors; not really.
I was more impressed with the 6.5" SF. Although, not bad for a 1st try.
Again good imaging - I think the high tweeter mounting is the way to go.
I like the new Discovery 1 Tweeter w/chamber, handles more power and goes lower.
The 6.5" and the Discovery tweeter might be a good combination. I would have to flip them and come up with a xo.
I thought the bass would rattle floors; not really.I was more impressed with the 6.5" SF. Although, not bad for a 1st try.
Again good imaging - I think the high tweeter mounting is the way to go.
I like the new Discovery 1 Tweeter w/chamber, handles more power and goes lower.
The 6.5" and the Discovery tweeter might be a good combination. I would have to flip them and come up with a xo.
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