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Super-tweeter, super-image, super-sound [message #48731]

Sat, 28 January 2006 18:52

Bill Epstein
Messages: 1088
Registered: May 2009
Location: Smoky Mts. USA

Illuminati (2nd Degree)

I'm sure Bowers and Wilkinson can feel my hot breath on their neck with my design:

I call it "NAUTILUS Pi"

By combining the tweeter baffle with the crossover I can swap resistors and caps with 'gator clips to find the best combination right at the source. Right now I'm digging 16 ohms across and 4.3 uF. That could change tomorrow

What won't change is the heretofore unheard with horns imaging I'm getting with this mount.

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Re: Super-tweeter, super-image, super-sound [message #48732 is a reply to message #48731]

Sat, 28 January 2006 21:18

Shane
Messages: 1117
Registered: May 2009

Illuminati (3rd Degree)

I can't believe it's not stained. And is that Royal Cable I see? I like the open baffle tweeter project, especially being able to change compnents at will.

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Re: Super-tweeter, super-image, super-sound [message #48733 is a reply to message #48731]

Sat, 28 January 2006 21:53

Wayne Parham
Messages: 18787
Registered: January 2001

Illuminati (33rd Degree)

Is that a DX25 on top? Or did you use one of the other models? I think Akhilesh uses an MG27 or another one like that. Some of the models are medium to high efficiency, others are lower.

I guess you must be padding down the compression horn, leaving the woofer and tweeter running full tilt. Is that pretty much how you have everything hooked up?

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Re: Super-tweeter, super-image, super-sound [message #48734 is a reply to message #48733]

Sun, 29 January 2006 04:48

Bill Epstein
Messages: 1088
Registered: May 2009
Location: Smoky Mts. USA

Illuminati (2nd Degree)

That's the DX-25 from a 2Pi kit I had on the shelf. I see there's a PL-27 that goes to 25,000 and costs a few bucks more.
And you're exactly right about the horn and woofer. 1.5 coil on the 2226 and .33uF/16ohms on the 902 horn.
There's a tendency for the 902 to get strident at higher levels that is partially masked by the Vifa. Ron suggested removing the cap and using more resistance. I'll try that but I also know the room is part of it.
Still, with this review sample CD player, which was the catalyst for the tweeter mod, I'm enjoying the best over-all sound ever.

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Re: Super-tweeter, super-image, super-sound [message #48735 is a reply to message #48734]

Sun, 29 January 2006 14:32

Wayne Parham
Messages: 18787
Registered: January 2001

Illuminati (33rd Degree)

What a neat deal.

Vifa makes a tweeter, part number MG27, but I think Parts Express stopped carrying it. Seems like they stocked it before the DX25. If memory serves, it's pretty similar but doesn't have as wide a surround.

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Re: Full Vifa line-up at Madisound [message #48739 is a reply to message #48735]

Sun, 29 January 2006 18:45

Bill Epstein
Messages: 1088
Registered: May 2009
Location: Smoky Mts. USA

Illuminati (2nd Degree)

Looks like PE smartened up and dumped the 80% of inventory that only accounted for 20% of sales.Especially with Ohio's Personal Property tax on business inventories.
I sure wish they'd clearance some Morel's; I really want to try the horn loaded tweet but not at $60 per.
Neither Madisound or Vifa have heard of this "iron law of retailing". I'm scratching my head over the differences between 4 MG series tweeters besides a couple of cycles Fs.

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Re: Full Vifa line-up at Madisound [message #48750 is a reply to message #48739]

Mon, 30 January 2006 09:11

Wayne Parham
Messages: 18787
Registered: January 2001

Illuminati (33rd Degree)

Gotcha, you're probably right.

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Thanks For The Idea [message #48765 is a reply to message #48731]

Tue, 31 January 2006 15:39

FredT
Messages: 704
Registered: May 2009

Illuminati (1st Degree)

Thanks for the idea. I tried it with two tweeters I had on the shelf, a cheap dome and a better quality ribbon. The cheap dome is a $14, 96dB, MCM #53-325 titanium dome. That's the one used in the Bottlehead Straight 8. It has a nasty peak at 3khz, but for this purpose I crossed it over above 10khz, 2nd order, using a 1uF cap with a 0.15mH shunt inductor. Not bad - it adds back just a touch of sizzle I'm accustomed to hearing with domes that aren't horn loaded, but not enough to cause excess siblance or to make the sound too tizzy. The ribbon is the $88, 95dB, Fountek 3.0. This one is really nice. It provides the sparkle I like to hear without a hint of tizz. A good test disk is Patricia Barber's Modern Cool. Early in track 8 there's a brush on a ride cymbal, first in the right channel then in the left - the supertweeter brings this out nicely without any apparent changes below about 10khz.

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Supertweeter Picture [message #48786 is a reply to message #48765]

Fri, 03 February 2006 11:43

FredT
Messages: 704
Registered: May 2009

Illuminati (1st Degree)

I shamelessly stole Bill's idea and built baffles for the Fountek ribbons. Here's one, still unfinished, sitting atop the main enclosure. The present crossover is a 1uF Solen cap with a 0.15mH shunt inductor, but some 1uF Audiocap Theta film & foil caps are on the way to replace the Solen. I plan to spray the baffle Claret Red to match the main baffle.