[tdogzthmn]

I was curious if anyone is running a super tweeter with their Omegas.

I had been reading about the Fostex T90A bullet tweeter and curious about what it might do with my Junior 8XRS speakers.  Coming from 2-way speakers I've notice a bit less air around cymbals and other metallic instruments and thought a super tweeter might help the upper octaves.

[FullRangeMan]

Never heard about it, they need xovers or capacitors.
Tweeters are not suited to match quality FR as Omega imo.

[DaveC113]

Worth a try imo.

I use T500s, they are a bit pricey but match/blend seamlessly. T90 will be good but not quite as neutral, maybe some metallic overtones from the Al diaphragm, but they will sound great on cymbals . I'd start around .47 uF for the cap value, and lower the capacitance rather than add an attenuator if it's too loud, add .1 uF caps in parallel if it's too soft. Halving the capacitance will reduce the SPL 6 dB.

I'd go with Jupiter copper foil caps, or Clarity ESA if Jupiter is too expensive. You could do .47 ESA and add .1 Jupiter too. You can also get really cheap film caps for testing first, then get better caps later.

You can also try up or back firing the tweeter, but if you can get a seamless result on-axis it's the best way to go imo.

Good luck!

 

[FireGuy]

I was curious if anyone is running a super tweeter with their Omegas.

I had been reading about the Fostex T90A bullet tweeter and curious about what it might do with my Junior 8XRS speakers.  Coming from 2-way speakers I've notice a bit less air around cymbals and other metallic instruments and thought a super tweeter might help the upper octaves.

I have seen a thread here addressing this enhancement.   Personally,  I wouldn't want to alter Louis' design.  For me their presentation is organic and pristine.  There's nothing I miss in it's designed freq range.  High end is just fine and I miss nothing.   If you believe adding a super tweeter is intriguing by all means...  IMO you might as well go with a traditional xover design and add (usually) the extra $$ to properly power them.

[Elizabeth]

My thoughts about higher than 20,000hz..
I would think about what happened at the US embassy and the high frequency attacks..
Then the fact a LOT of digital gear generates huge HF trash..
So IMO unless you are using exclusively turntable only..
And no digital gear.. Or digital gear which has a clear effort to block the self created digital HF trash from the signal path.
So...
I would avoid anything attempting to communicate to dogs, cats, birds, bats and dolphins.

Also, you would need to know if your gear can actually PASS a signal over 20,000hz? Some components block it. other go right up to a measured 100,000hz..

[FullRangeMan]

Then the fact a LOT of digital gear generates huge HF trash..

Mainly compressed formats as MP3, there is a lot of jitter on treble.

[pstrisik]

I use supertweeters.  These are SB Acoustics Satori beryllium tweeters I picked up.  Purchased a pair of black plastic project boxes, used teflon caps from ebay, and binding posts.  Made the "baffles" out of red oak from Lowe's.  Inside, I have the positive leads from the binding posts and from the drivers with aligator clips which clip securely to the leads on the caps.  This allows easy changing of them.  Pictures below.  I also have a pair less elegantly constructed using vintage Pioneer beryllium ribbon tweeters and a pair of baffles with vintage Yamaha beryllum tweeters that can swap with the Satoris on the project box.

I have them amped separately with 25 watt Temple Audio Bantam Gold.  I use Roscoe's method of changing cap values for the roll off and output level to some degree, though the Bantam has a volume control. 

In discussions with Louis, he encouraged having the tweeters not point forward.  I have them pointed upwards.  He said forward would affect the point source advantage of the Omegas. 

They provide high end improvement when I'm using my Inspire SEP tube amp and when I use the Nelson Pass designed, but kit built ACA monoblocs.  However, I acquired a First Watt J2 and found I don't need them at all.  Using them degrades the sound, probably by providing too much high end frequency.  If I were to use them with the FW, I would change the cap value to have them roll off even higher. 

Satori:

 


Yamaha:

[DaveC113]

Domes and ribbons without waveguides won't work out as well on-axis as the dispersion pattern is very different. Horn tweeters match dispersion pattern better but any tweeter would also need to match timbre or it will sound off. It isn't easy to get drivers to match seamlessly, hence the whole single-driver thing I'm not a huge fan of up/back firing drivers personally but it can work.

Reducing cap value to attenuate a tweeter is a decades-old technique afaik...

[doggie]

I tried the T90a with my old pair of Super Alnico floorstanders and could never really get them dialed in. I used one high quality cap(tried many values) and an lpad to adjust them but if anything they detracted from the sound. I was using a First Watt amp also.

It is pretty hard to improve upon one of Omegas Alnico speakers.

[DaveC113]

I tried the T90a with my old pair of Super Alnico floorstanders and could never really get them dialed in. I used one high quality cap(tried many values) and an lpad to adjust them but if anything they detracted from the sound. I was using a First Watt amp also.

It is pretty hard to improve upon one of Omegas Alnico speakers.

I tried the 96H and it never worked out either, it just sounded too different from the Omega driver.

I agree it's hard to improve upon the Omega drivers by adding a tweeter.

[MttBsh]

For many years I have been using a pair of Cain & Cain Abbys. I love the sound these single driver speakers put out but they are somewhat bass-shy so I added a pair of subs at the back of the room to fill in the low end and a pair of Fostex T900A tweeters next to he Abbys to bring out more sparkle up top. The sound from this setup leaves nothing to be desired, at least for my tastes.

[guf]

I tried the T90a with my old pair of Super Alnico floorstanders and could never really get them dialed in. I used one high quality cap(tried many values) and an lpad to adjust them but if anything they detracted from the sound. I was using a First Watt amp also.

It is pretty hard to improve upon one of Omegas Alnico speakers.

same, same, same...

but i'm going to try again.

[DaveC113]

The T900 and T500 have Mg diaphragms and this may be key to having the drivers match well. Unfortunately, both are expensive.

[ohenry]

If extending the high frequency is the goal, try a T90a with a 0.22uF uF cap.  With the small caps, the T90a seems to not add volume, just extension.

I've tried 0.47uF and 0.33uF caps and the Fostex interfered with the Bozak CG speaker's high frequency output.  The frequency overlapping wasn't a good thing. 

So, I can't tell you how the silver bullets will integrate with your Omegas, but if you are missing a sparkle here and there, it may be worth a gamble.  I like mine when they are adequately harnessed.