So you are buying headphones now? Thats a relief. Headphones are a much better idea then all this OB nonsense. You've come to your senses finally
(just joking)Fair pointView attachment 1093154
So you are buying headphones now? Thats a relief. Headphones are a much better idea then all this OB nonsense. You've come to your senses finally
Sometimes I'm wondering how far one should go: are things getting too big and complicated? Why not just build a small full range magnetic driven bookshelf? But in the end, I really enjoy the information on this forum and spending hours of woodworking, testing, etc. Futhermore, the idea that one is building its own driver (esl panel) still gives me a big sense of joy, especially the moment after 100+ hours of implementing, when I carefully open the volume knob and sound is coming from the new panels.
@kazap: very impressive.....
Btw, these are the recommended ranges by Calvin:
4 Ohms version of Dayton RS-180: Qts=0.46, Qes=0.59
8 Ohms version of Dayton RS-180: Qts=0.31, Qes=0.42
All other params fall in the reccommended ranges. So Qts of the 4 ohms version seems to fit better, so I guess the 4 ohms version would be the best option?
Btw, these are the recommended ranges by Calvin:
- diam: 16-18cm
- fs ~35-40Hz
- Qts ~0.4-0.5
- Qes ~0.45-0.6
- Vas ~20-30L
- Xmax >4mm
4 Ohms version of Dayton RS-180: Qts=0.46, Qes=0.59
8 Ohms version of Dayton RS-180: Qts=0.31, Qes=0.42
All other params fall in the reccommended ranges. So Qts of the 4 ohms version seems to fit better, so I guess the 4 ohms version would be the best option?
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If you're not trying to use the natural response/roll-off of the driver as a significant part of the design, I don't think it's of as much concern if it has lower Qts. Active EQ will serve the same function as the higher Qts driver in a passive design.
If you're not trying to use the woofer all the way to its resonance, even more so.
As an example, the Linkwitz LX521 uses:
Seas U22REX/P-SL with a Qts of 0.29
Seas L26RO4Y with a Qts of 0.27
If you're not trying to use the woofer all the way to its resonance, even more so.
As an example, the Linkwitz LX521 uses:
Seas U22REX/P-SL with a Qts of 0.29
Seas L26RO4Y with a Qts of 0.27
The 8ohm has more wire on the coil with a stronger motor for free. If you are going to use amps with good dampening and current drive Id be looking at the 8ohm wired in parallel. Especially if you are pushing freg up into the midrange and dont want the driver resonating away after the ESL has moved on....
Maybe look at all the specs? Load http://www.loudspeakerdatabase.com/Dayton/RS180 4ohm in one tab and 8ohm in another and flick between.
It looks like the 8ohm coil increases Bl and that changes the associated Thiele/Small parameters on the left, making the driver more able to be controlled by a grippy amp and less wobbly?
Also if the wings are perpendicular the helmholzresonator is also more "efficient" and not desireble.
So they shall be tapered and also angeld approx 45deg or more. I have studied that in combination with Quad electrostats. The goal was to move the -3dB point at low frequencies with 10 Hz by increasing the efficiency. And it is absolutey possible by extending the baffle size.
So they shall be tapered and also angeld approx 45deg or more. I have studied that in combination with Quad electrostats. The goal was to move the -3dB point at low frequencies with 10 Hz by increasing the efficiency. And it is absolutey possible by extending the baffle size.
Hi,
the tapering lowers the base Fs of the driver a bit. You can expect 2 to 5Hz lower.
Qtc also rises slightly. Efficiency drops slightly too ... but using 6+ drivers it doesn't play a role.
It introduces a slightly increased chamber resonance at the upper bandwidth range though.
A sheet layer of damping material should deal with that issue.
The almost tiny crossectional dimensions ensure the resonance falls outside above the intended working range.
Apart from the fact that more parameters improve than worsen in this special application, the tapering serves a esthetical reason also.
Since the sides 'disappear' even when the system is looked at from a slight angle, the appearance is even thinner, lighter, less boxy, more open baffle like.
jauu
Calvin
the tapering lowers the base Fs of the driver a bit. You can expect 2 to 5Hz lower.
Qtc also rises slightly. Efficiency drops slightly too ... but using 6+ drivers it doesn't play a role.
It introduces a slightly increased chamber resonance at the upper bandwidth range though.
A sheet layer of damping material should deal with that issue.
The almost tiny crossectional dimensions ensure the resonance falls outside above the intended working range.
Apart from the fact that more parameters improve than worsen in this special application, the tapering serves a esthetical reason also.
Since the sides 'disappear' even when the system is looked at from a slight angle, the appearance is even thinner, lighter, less boxy, more open baffle like.
jauu
Calvin
Mostly since you are considering the Dayton drivers, I'll voice my opinion here.
1) I am in 100% agreement with Calvin about the smaller drivers being much preferred. There's a 'sluggishness' with the larger ones.
Even as I failed to see it in measurements properly, it's audible. (my guess? test procedures, given no anechoic chamber..
)
2) Question: Does EQ-ing a driver lower simulate adding moving mass to the cone or..?
1) I am in 100% agreement with Calvin about the smaller drivers being much preferred. There's a 'sluggishness' with the larger ones.
Even as I failed to see it in measurements properly, it's audible. (my guess? test procedures, given no anechoic chamber..
)2) Question: Does EQ-ing a driver lower simulate adding moving mass to the cone or..?
Hi thanks a lot for all the replies and good explanations of the effect of the tapering "wings". I already bought 12 Dayton RS-180-4 drivers, and I think I have a OB desing now to implement. It has a front baffle of 22 cms width, the panel will be 155 cms tall, like my electrostats, and depth of the "wings" will be 18 cms. These wings will be angled inwards. I add bracing to make the construction stiffer.
I think these sheets of damping material will be attached to the inner surfaces of the side "wings"?
Thanks again!
Any suggestion about which damping material would be suitable to dampen the slightly increased chamber resonance? I guess I can measure the camber resonance and as the cabinet is almost ready I can test it soon. I will post some photos soon as well. It was a quick built, but it looks nice to my eyes Hope sound quality wise it will be an improvement too.
I have some 9mm sheep whool felt left over from flooring insulation. Would that be suitable to dampen these low / mid frequencies?
Any suggestion about which damping material would be suitable to dampen the slightly increased chamber resonance? I guess I can measure the camber resonance and as the cabinet is almost ready I can test it soon. I will post some photos soon as well. It was a quick built, but it looks nice to my eyes
Hope sound quality wise it will be an improvement too.I have some 9mm sheep whool felt left over from flooring insulation. Would that be suitable to dampen these low / mid frequencies?
The most effective place to place sound absorbing material is where the air speed is highest! This is contradictory or contrast to what 99% of speaker manufacturers do when they place padding to the wall of the box.... almost useless!! The air speed is close to zero in midrange but at high frequency (tweeter frequency) it could work. but woofer and subwoofer????
There is some very few speaker engineers in the world that I have stumbled across: Carlsson and Sven Tyrland who made etensive measurements during his time at the Technical university of Chalmers developing what will become the Stridbeck TL6 (I have hade those monsters beginning of 1990 and later as subwoofers for ESL 63). They wrapped the insulation around the basket of the drivers! Other high end speaker i have seen they fill the cabinet with 100% of damping material. The most elegant way is of course to keep all the damping as close to the cone itself!
There is some very few speaker engineers in the world that I have stumbled across: Carlsson and Sven Tyrland who made etensive measurements during his time at the Technical university of Chalmers developing what will become the Stridbeck TL6 (I have hade those monsters beginning of 1990 and later as subwoofers for ESL 63). They wrapped the insulation around the basket of the drivers! Other high end speaker i have seen they fill the cabinet with 100% of damping material. The most elegant way is of course to keep all the damping as close to the cone itself!
Hi,
since this style of bass cabinet is so tiny a small sheet of damping material almost fills the complete space left by the drivers ;-)
Putting the stuff on the inner side walls is nearly the same as covering the basket and nearly the same as filling up the whole space.
With the ESL MK2 where the drivers are mounted from inside to the front panel, I couldn't even mount the drivers through the backside slot, but had to use the bottom opening to slide-in and -up the drivers into their position.
Heck, the thing is so small I even had to design a way to fix the driver to the front panel wo using the mounting holes in the basket front.
jauu
Calvin
since this style of bass cabinet is so tiny a small sheet of damping material almost fills the complete space left by the drivers ;-)
Putting the stuff on the inner side walls is nearly the same as covering the basket and nearly the same as filling up the whole space.
With the ESL MK2 where the drivers are mounted from inside to the front panel, I couldn't even mount the drivers through the backside slot, but had to use the bottom opening to slide-in and -up the drivers into their position.
Heck, the thing is so small I even had to design a way to fix the driver to the front panel wo using the mounting holes in the basket front.
jauu
Calvin