Speaker design challenge: 105db 20 - 20k at listening position

Status
Not open for further replies.
This is a future upgrade project, for both music and home theatre. My goals are:

*105 db peaks at listening position (115 at 1m) without a little extra output in reserve if possible
*20Hz - 20k response
*room interaction is a critical factor so I would count out a conventional floorstander with monopole subwoofer - controlled directivity and polar response desirable
*I prefer a relaxed sound that is a little more forgiving than an ultra high resolution that makes typical recordings sound bad

How would you approach this challenge? What would be your design?
 
Some inspiration

http://www.dnaudio.com/index.htm/
http://www.legacy-audio.com/2004/whisper.html
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.


http://ldsg.snippets.org/HORNS/unity2.html
An externally hosted image should be here but it was not working when we last tested it.


I've been considering some kind of combination of some of the following ideas:

- large coax drivers like Adire HE12
- point source arrays with 4 mids in formation around a central tweeter in a waveguide - similar to Legacy Audio with their Helix and Whisper speakers
- dipole from 30 - 200 Hz
- open baffle midrange
- CD horn (is it possible to get this sweet sounding?)
- unity horn clone
 
paulspencer said:
This is a future upgrade project, for both music and home theatre. My goals are:

*105 db peaks at listening position (115 at 1m) without a little extra output in reserve if possible
*20Hz - 20k response
*room interaction is a critical factor so I would count out a conventional floorstander with monopole subwoofer - controlled directivity and polar response desirable
*I prefer a relaxed sound that is a little more forgiving than an ultra high resolution that makes typical recordings sound bad

How would you approach this challenge? What would be your design?


105dB for 20Hz is asking doe a large room.
 
105dB for 20Hz is asking doe a large room.

My current system achieves this easily with a pair of sealed subwoofers. In vented boxes they could approach 120db. This is the easy part. If you want more bass, you can easily add more subwoofers, and there are benefits in smoothing in-room response. However, you can't do this at the top end! It seems to me that the treble is the difficult part ...
 
That would be AU $928, almost double the cost of the SS ring radiator! I'd never spend that much on a tweeter, even if merely for the added stress of "what if someone damages it........"

"nice compression driver?"

hmmm ... I heard a HE10 (Adire) and the treble was awful! When it approached anything above "moderate" output, it became very harsh. At low output it was not bad. Next do a hifi dome tweeter it was very ordinary.

I would still like to know if it's possible for a CD to actually have a sweet sounding treble like that of a hifi dome tweeter ... or is it expensive to get one that will sound like that?
 
did this and failed

I did something like this with two ht10 and two vented 15 B&C subs powered by two hefty bad a## poweramps.It tured out the he10 tweeter was the weak link and soon had to be replaced.I used the threaded BMS 4540nd as a replacement and had to tweak the crossover heavily. The 4549nd will keep up but works better in a larger horn than inside the beta cx10 used in the ht10. It also have a large bump in the 2-6k area and thereafter a dip and then slowly rising to 114db at 20k. In other words nice for a CD horn with a high corossover point or with a eq cirquit on the crossover.
Maybe a pa driver such as a phl to cover 200-5k?
 
what compression drivers have you heard?

The "nice" ones have extended top end and are very detailed/great sounding drivers....the not so nice ones have no top end(usually 10-13khz max) and details get lost or non-existant
 
The Seas Millennium can do 105dB/1m in full space at 2K when driven to Xmax. Add 6dB for half space (on a baffle) radiation and another 6dB for the contribution of the midrange with a 2K LR4 crossover. That gives you 117dB/1m which meets your design goal with 2dB to spare.
 
The Heil AMT - big ones, dipoles with the old soft diaphagms, crossover around 1.8K with 4th order electronic crossover, no problem doing 105db at 5 meters, better than very expensive compression drivers and horns and no super tweeter needed.
 
Status
Not open for further replies.