I do not think any of this is "super simple" but here's a few other options to consider... and perhaps building a three way.
1) Two drivers that cover 700Hz and up:
Selenium D250-X GW 1" Phenolic Horn Driver 1-3/8"-18 TPI
Tang Band 75-1558SE 3" Textile Dome Midrange
2) For a two way I think a Fast is best using a full range driver and woofer. Pick your poison and enjoy!
Btw, I was at the NY Audio Show and some of the best sound came from tiny little boxes using Mark Audio's $40 drivers - but they were heavily equalized and the total system cost $12,000. They certainly covered 700Hz to 7kHz.
3) And finally, something like this is a possibility tho it would bring your crossover up to about 800Hz... but I bet it sounds pretty good.
Eminence N320T-8 2" Neo Compression Driver 8 Ohm 4-Bolt
1) Two drivers that cover 700Hz and up:
Selenium D250-X GW 1" Phenolic Horn Driver 1-3/8"-18 TPI
Tang Band 75-1558SE 3" Textile Dome Midrange
2) For a two way I think a Fast is best using a full range driver and woofer. Pick your poison and enjoy!
Btw, I was at the NY Audio Show and some of the best sound came from tiny little boxes using Mark Audio's $40 drivers - but they were heavily equalized and the total system cost $12,000. They certainly covered 700Hz to 7kHz.
3) And finally, something like this is a possibility tho it would bring your crossover up to about 800Hz... but I bet it sounds pretty good.
Eminence N320T-8 2" Neo Compression Driver 8 Ohm 4-Bolt
There's also this tweeter from SB acoustics tested by Troels that has the lowest HD levels I've ever seen at 1khz
SBAcoustics-tweeters
If fitted to a shallow waveguide and then equalizing the boost of the guide to flat, you might just get to a 700-800hz crossover range with a steep filter. Won't go very loud, but for a day to day in house speaker, might be just what you ordered.
SBAcoustics-tweeters
If fitted to a shallow waveguide and then equalizing the boost of the guide to flat, you might just get to a 700-800hz crossover range with a steep filter. Won't go very loud, but for a day to day in house speaker, might be just what you ordered.
There is 1/3 octave smoothing in Spec sheet measurements - wiggles in treble are smoothed away. No idea about the sound.
The maximum acoustic output of a 1" diaphragm around 700Hz is very low.
If you listen at a whisper the IM distortion may not be horrible.
I once derived some approximate limits but those notes are packed. But even a 3KHz limit on a 1" dome is pushing it.
I have worked toward "Constant Directivity" since the 1970s.
> constant narrow directivity speaker... is not {easier}.
A constant narrow angle is not terribly hard with a LARGE horn. IMHO much easier than constant broad directivity.
90x90 degree 1KHz up can be done with about a 12x12x12" box. A 1" throat will stay 90 degrees well above your 7KHz goal; and there are tricks I used to go higher.
I once built a very tight 35x30 900Hz-up horn to throw a small patch of speech across a very large room. (Booth to stage talkback) Face was about 2 foot across, horn was over 3 feet long. At 30 degrees, throat size was not a limit for high freq directivity.
I have pencilled a horn 60 deg at 250Hz and 30 deg above 500Hz, 4 foot mouth 8 feet long. A 4" cone would easily hold the pattern to 7KHz. At the face it would sound funny. From 40 feet away it should sound stunning. The real goal is to throw sound 4,000 feet to annoy some neighbors. (But they are not worth 4 sheets plywood and a fat 15".)
Neither of these would be at ALL pleasant living-room speakers!!
"Broad" pattern in a single driver conflicts with power output requirements.
The "conventional" multi-way systems do different things but tend to be reasonable compromises on ALL requirements.
The game-breaker would be many drivers in array. You can staple cardboard into a dodecahedron, put a 4" cone in each face, and get 360 degrees every way. It doesn't suck bad. It sucks some in interference between drivers. (And doing it in wood would be a woodworker's nightmare.)
Remember that most packaged music has been mixed/mastered on rising-directivity monitor speakers. The "Constant Directivity" goal has merit, but more in the abstract than real-world.
I think that the recently developed bending-mode-radiator (BMR) drivers can break the rules you set forth above. You can use them in a small enclosure from 700Hz and up, or OB/nude as low in frequency as power input allows (1.5k?). At high frequencies the off axis performance (at least in the front hemisphere, by my measurements of one model) is close to CD (close enough for me). Not a high SPL compression driver on a horn, but that is not what I am after.
See attached pic for an example (this is 'nude' e.g. driver in free air) of response at 0-30-60-90 degrees off axis and the on-axis distortion (at maybe 1W input power). I am using this as the tweeter in an OB loudspeaker project that I have started to build.
Attachments
........or 24 in an array?....is what i was thinking! Cheap enough
Oh yes it could be interesting, better 48! Probably a bit light on low end but could be worth a try.
This is in the same family as the one I posted about, above, with my measurement. But this one has a very low sensitivity of 80dB/W, and correspondingly low power handling of 10W, 20Wmax. But yes, BMR's have very good off-axis response at the high end (for a 2" diameter driver) while having healthy Xmax (this one has 2.5mm).
But this one has a very low sensitivity of 80dB/W, and correspondingly low power handling of 10W, 20Wmax.
Yes it was the main concern i expressed about dynamic behavior. With a bit of a search it could be possible to find one more suitable.
Which ref is the one you posted CharlieLaub?
Yes it was the main concern i expressed about dynamic behavior. With a bit of a search it could be possible to find one more suitable.
Which ref is the one you posted CharlieLaub?
This one:
Tectonic Elements TEBM46C20N-4B BMR 3" Full Range Speaker 4 Ohm
I used that one in a center channel speaker as a mid/tweet. Nice......but not as nice off axis as the small 2" i mentioned....since we were talking directivity.
The 3" worked great in the CC application though. Crossed it at 250hz to a pair of designer series 4" woofers in a horizontal MTM. Took the design principle from Cambridge
The 3" worked great in the CC application though. Crossed it at 250hz to a pair of designer series 4" woofers in a horizontal MTM. Took the design principle from Cambridge
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