Bass,
With all that free time why don't you come down to Costa Rica for a couple of months? I've got a ton of audio projects that I'll gladly share. They range from things like ultra compact OB woofer cabs to testing whether cryo treatment and burnin of speaker cables make any audible difference. As an added bonus el cheapo room acoustic treatments that are better than the expensive stuff.
With all that free time why don't you come down to Costa Rica for a couple of months? I've got a ton of audio projects that I'll gladly share. They range from things like ultra compact OB woofer cabs to testing whether cryo treatment and burnin of speaker cables make any audible difference. As an added bonus el cheapo room acoustic treatments that are better than the expensive stuff.
Hi
You know, you could also build a horn for your driver.
I lean towards them myself.
If you want to try one, I’ll take a whack at some specifics for you since you’re a fellow Illiniosian who who’s prone to make saw dust.
You want to scare your self, a proper horn is how.
Cheers,
Tom Danley
How about the sox eh, man!
You know, you could also build a horn for your driver.
I lean towards them myself.
If you want to try one, I’ll take a whack at some specifics for you since you’re a fellow Illiniosian who who’s prone to make saw dust.
You want to scare your self, a proper horn is how.
Cheers,
Tom Danley
How about the sox eh, man!
A horn that would reach 27~25 Hz in corner loading has already been designed (you designed it), and while it's practical for pro sound use, for the performance gains in a small room like that, it's almost too big. This is subjective, I know, but it would take up almost 5-10% of any normal room! Unless you are planning on generating a DIY Tapped Horn, which would be something to see, just in general. I don't know if practicality would be one of BassAwdyO's concerns but he could just take a look at people who have done two LABHorns in their listening room and decide if he can part with that kind of square (or cubic) footage.
Thanks for dropping by Mr. Danley,
Yes, I would like to scare myself!!!
I actually had been considering building a horn for this driver in the past, but got sidetracked somewhere(probably around the design phase).
I definately am one fellow Illinoisian who will make some sawdust... and alot of it I may add(and probably not clean it up for, a little while).
What kinda size are we looking at here? Labhorn size seems acceptable. Bigger, might not go into my living room, but It could definately take up some space out in my 2 story 24'x24' garage!
MDF has also been on sale pretty cheap lately also. $12.99/sheet sure beats the typical $21.99 they had been asking for it.
Yes, I would like to scare myself!!!
I actually had been considering building a horn for this driver in the past, but got sidetracked somewhere(probably around the design phase).
I definately am one fellow Illinoisian who will make some sawdust... and alot of it I may add(and probably not clean it up for, a little while).
What kinda size are we looking at here? Labhorn size seems acceptable. Bigger, might not go into my living room, but It could definately take up some space out in my 2 story 24'x24' garage!
MDF has also been on sale pretty cheap lately also. $12.99/sheet sure beats the typical $21.99 they had been asking for it.
OK so here's something VERY strange....
I can bottom out the sub easily at 30hz
Is WinISD just that far away from accurate on it's excursion calculator? it says with 1200watts I should be at right around 24mm one way @ 30hz... instead I'm past 34mm one way which it predicts at over 2500watts. Either WinISD is whack, or adire seriously under rates their amps... in either case I am scared for the life of my driver and I have employed drastic EQ cuts below 40hz.
If adire is under rating the amp by that much I'd be scared not only for the driver's mechanical stresses, but that the voice coil may fry!!! Of course the thermal rating might be under rated by that degree also, but I dont want to find out.
I can bottom out the sub easily at 30hz
Is WinISD just that far away from accurate on it's excursion calculator? it says with 1200watts I should be at right around 24mm one way @ 30hz... instead I'm past 34mm one way which it predicts at over 2500watts. Either WinISD is whack, or adire seriously under rates their amps... in either case I am scared for the life of my driver and I have employed drastic EQ cuts below 40hz.
If adire is under rating the amp by that much I'd be scared not only for the driver's mechanical stresses, but that the voice coil may fry!!! Of course the thermal rating might be under rated by that degree also, but I dont want to find out.
If it takes less power than simulated, perhaps there is more gain than WinISD predicts. It's also possible that the source itself has stronger than average content at 30 Hz which is effectively like getting more gain.
I can get more excursion than it seems to predict as well in some situations. This is even true with dance music with exaggerated midbass.
I have always suspected that you shouldn't rely totally on simulations to tell you how much power is required to reach xmax.
In your case this is a good thing and you have nothing to worry about. This is better than never getting close to xmax! It would be a waste to spend so much on 34mm xmax and only be able to use half of it!
Now this is getting silly - be suspicious of the accuracy of a computer simulation system before something like this!
That's like Bill Gates worrying he is going to spend all his money before he retires!
If you can't safely run a 1kw driver with 34mm xmax, then there is no hope for you!
There is no reason to think this.
Adire website:
Running a 1kw driver with a 1.2kw amp is very safe from a thermal point of view. You can easily use an amp rated at twice the thermal rating of the driver without cooking the driver as long as the continuous level is not running constantly four hours on end.
Knee jerk reaction perhaps?
I recall you saying you didn't need a rumble filter and now you want to cut back below 40 Hz?! You have designed an extreme EBS, hence you are giving up some midbass in order to handle more subsonic bass. If the midbass is starting to disapoint, then perhaps what you want is higher tuning. An EBS loses midbass output as the gain from the port is so far below the midbass.
I can get more excursion than it seems to predict as well in some situations. This is even true with dance music with exaggerated midbass.
I have always suspected that you shouldn't rely totally on simulations to tell you how much power is required to reach xmax.
In your case this is a good thing and you have nothing to worry about. This is better than never getting close to xmax! It would be a waste to spend so much on 34mm xmax and only be able to use half of it!
Now this is getting silly - be suspicious of the accuracy of a computer simulation system before something like this!
That's like Bill Gates worrying he is going to spend all his money before he retires!
If you can't safely run a 1kw driver with 34mm xmax, then there is no hope for you!There is no reason to think this.
Adire website:
Running a 1kw driver with a 1.2kw amp is very safe from a thermal point of view. You can easily use an amp rated at twice the thermal rating of the driver without cooking the driver as long as the continuous level is not running constantly four hours on end.
Knee jerk reaction perhaps?
I recall you saying you didn't need a rumble filter and now you want to cut back below 40 Hz?! You have designed an extreme EBS, hence you are giving up some midbass in order to handle more subsonic bass. If the midbass is starting to disapoint, then perhaps what you want is higher tuning. An EBS loses midbass output as the gain from the port is so far below the midbass.
Here's the strange thing though paul....
Doing a 10-100hz sweep I turn it all the way up. At 10hz xmax isnt reached, at 20hz the sub comes VERY close to XMAX, a bit above 20hz it goes beyond Xmax. I turn it down. Excursion INCREASES up to about 30hz and then starts to decline once again to a safe amount for full power once again at ~40hz. Now Maybe something's wrong with my soundcard or the signal generator and the reference level is going up and down, but something funky is going on here. Looking at the waveform of the soundcard output it shows no clipping through the entire sweep.
It seems like the excursion curve is resembling a BR although at this point I'm only using it as a sealed box. Maybe something funny is going on inside the box with those holes?
Doing a 10-100hz sweep I turn it all the way up. At 10hz xmax isnt reached, at 20hz the sub comes VERY close to XMAX, a bit above 20hz it goes beyond Xmax. I turn it down. Excursion INCREASES up to about 30hz and then starts to decline once again to a safe amount for full power once again at ~40hz. Now Maybe something's wrong with my soundcard or the signal generator and the reference level is going up and down, but something funky is going on here. Looking at the waveform of the soundcard output it shows no clipping through the entire sweep.
It seems like the excursion curve is resembling a BR although at this point I'm only using it as a sealed box. Maybe something funny is going on inside the box with those holes?
"I was looking at tuning right around 16hz in 6 cubic feet, but with a single passive it doesnt seem possible as the highest tuning allowed is 13hz."
I believe the diaphragms are just MDF, so you could thin it.
But I'd just get the second one.
"Remember a PR is a driver minus a motor, hence the output from the PR will have compression related to increased suspension stiffness with excursion."
Also remember that the suspension spring is in parallel with the air spring, which is stiffer than the suspension for any Vb less than Vas.
This reduces the total effective nonlinearity.
"1. Tuned that low it is likely to sound terrible for music, loose and sloppy and you can't stuff a PR like you can a port."
Actually the lower the tuning, the closer a vented/PR system's behavior is to a sealed systems in all respects. At Fb = 0 they're the same.
"2. For HT the group delay is going to be so high that when you see the dinosaur step here on the video you'll hear, rather feel, the footstep like it was 10 or 20 meters further away. While it may feel cool and go unnoticed, it still won't be accurate."
This has never been found to be the case in tests designed to show audible differences caused by group delay.
"For someone worried about port noise, you sure didn't concern yourself with air moving freely in your cab."
While ports have high air displacements and velocities, their much lower from the drivers and PR's because of the much larger areas.
"You can easily use an amp rated at twice the thermal rating of the driver without cooking the driver as long as the continuous level is not running constantly four hours on end."
Maybe seconds on end.
As Dan Wiggins said here
http://forum.carstereos.org/showthread.php?t=55762
"...the voice coil in a Tumult - 3" diameter an 1.6" long - reaches 200+ deg C in a matter of a second or two with 1000W of power."
And Tom could tell you a thing or two about speaker rated power vs. real power
Just consider what 1000 W does to the thick fan-cooled heating wire in a portable heater, and think about the same power applied to a voice coil confined in a small space, and the speaker all sealed up in a well insulated box.
I'm surprised speakers don't burst into flames with fair regularity.
I believe the diaphragms are just MDF, so you could thin it.
But I'd just get the second one.
"Remember a PR is a driver minus a motor, hence the output from the PR will have compression related to increased suspension stiffness with excursion."
Also remember that the suspension spring is in parallel with the air spring, which is stiffer than the suspension for any Vb less than Vas.
This reduces the total effective nonlinearity.
"1. Tuned that low it is likely to sound terrible for music, loose and sloppy and you can't stuff a PR like you can a port."
Actually the lower the tuning, the closer a vented/PR system's behavior is to a sealed systems in all respects. At Fb = 0 they're the same.
"2. For HT the group delay is going to be so high that when you see the dinosaur step here on the video you'll hear, rather feel, the footstep like it was 10 or 20 meters further away. While it may feel cool and go unnoticed, it still won't be accurate."
This has never been found to be the case in tests designed to show audible differences caused by group delay.
"For someone worried about port noise, you sure didn't concern yourself with air moving freely in your cab."
While ports have high air displacements and velocities, their much lower from the drivers and PR's because of the much larger areas.
"You can easily use an amp rated at twice the thermal rating of the driver without cooking the driver as long as the continuous level is not running constantly four hours on end."
Maybe seconds on end.
As Dan Wiggins said here
http://forum.carstereos.org/showthread.php?t=55762
"...the voice coil in a Tumult - 3" diameter an 1.6" long - reaches 200+ deg C in a matter of a second or two with 1000W of power."
And Tom could tell you a thing or two about speaker rated power vs. real power
Just consider what 1000 W does to the thick fan-cooled heating wire in a portable heater, and think about the same power applied to a voice coil confined in a small space, and the speaker all sealed up in a well insulated box.
I'm surprised speakers don't burst into flames with fair regularity.
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