Joined the passive subwoofer club

lovinthehd

lovinthehd

Audioholic Jedi
After his tirades aimed at me, meh, no missing ol' mikey and his various idiotic postings.
 
Verdinut

Verdinut

Audioholic Ninja
The box that I have is 23”x23”x23” and has a 6” round port that is about 22” long. You are correct about the driver it’s the Ultimax 15-22. I would really appreciate your thoughts and would enjoy if you could share the frequency response charts for the tuning it has now and if I could get close to a .20hz f3 or a little lower I would be happy but I understand that I’m limited with how low it can go due to box size. Thanks so much for offering to help. If I left any information out just ask.
The size of your box limits the low frequency response. The info that Parts-Express supplied to you is exact.

If you want a better LF performance, you would need an internal net volume of at least 10 cf. The 11.1 cf specified by Parts-Express on their site is the optimum net volume for your driver. The laws of physics are not flexible.

Parts-Express say that with the 11.1 cf net internal volume, taking into account the space taken by the driver, the bracing and the pipe., you could get an F3 at 17 Hz. I can confirm that their info is exact: Box tuning at 15.9 Hz with one pipe duct of 6" diameter and 22.25" long. Should you want to build a bigger box, the volume taken by the Ultimax 15-22 is 0.61 cf.

Final note: The polyfil should be glued to the panels
 
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AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
Ha ha. Looks like ole Mike was just pulling my chains. He got me good this time. :D

So anyway, Mike called me and was laughing his head off. :D

He'll be coming back to the forum soon.
 
ryanosaur

ryanosaur

Audioholic Spartan
Ha ha. Looks like ole Mike was just pulling my chains. He got me good this time. :D

So anyway, Mike called me and was laughing his head off. :D

He'll be coming back to the forum soon.
Boy who cried wolf, much?!
I want my gif-liquor back!
 
CajunLB

CajunLB

Senior Audioholic
Ha ha. Looks like ole Mike was just pulling my chains. He got me good this time. :D

So anyway, Mike called me and was laughing his head off. :D

He'll be coming back to the forum soon.
Well that’s a relief. Was it a miscommunication or did Mike set you up?
 
Shanman

Shanman

Audioholic
The Crown amps high pass filter doesn't go low enough to be useful for protection below tuning for a ported sub.

You'd need to add sufficient dsp like in the form of a minidsp or similar. This is the one advantage of the Behringer amps that included such dsp....

Otherwise I've enjoyed my several XLS amps for use for subs or mains....
Splain and/or remind me something Chris. As you know, back when the Snell plate amp failed, I tried a few different amps to passively re-power the ported sub. I tried the Crown because I liked the crossovers built in, but ultimately went with an Outlaw 2200 with my Denon AVR-X3300 providing LP crossover control . Am I missing something, or should I also have some sort of HP limiting to protect the sub?
 
CajunLB

CajunLB

Senior Audioholic
The size of your box limits the low frequency response. The info that Parts-Express supplied to you is exact.

If you want a better LF performance, you would need an internal net volume of at least 10 cf. The 11.1 cf specified by Parts-Express on their site is the optimum net volume for your driver. The laws of physics are not flexible.

Parts-Express say that with the 11.1 cf net internal volume, taking into account the space taken by the driver, the bracing and the pipe., you could get an F3 at 17 Hz. I can confirm that their info is exact: Box tuning at 15.9 Hz with one pipe duct of 6" diameter and 22.25" long. Should you want to build a bigger box, the volume taken by the Ultimax 15-22 is 0.61 cf.

Final note: The polyfil should be glued to the panels
With the box and port that I have where would you set the high pass? Btw got the Dayton dsp amplifier back in service. I somehow pinched and cut my input rca. That being said I now have 20/25/30 hz options not sure what the slope is though.
 
Replicant 7

Replicant 7

Junior Audioholic
He owes me a bowl of “primo” cause I smoked an extra bowl for my fallen Audiohomie.
Well since Louisiana just made having less than, is it 2 ounces of weed just a fine. I can definitely see that happening coming Your way very soon!! ;)
 
CajunLB

CajunLB

Senior Audioholic
Well since Louisiana just made having less than, is it 2 ounces of weed just a fine. I can definitely see that happening coming Your way very soon!! ;)
I’m clowning around but I’m prescibed medical THC oil and it works fantastic for several of my ailments.
.
 
Replicant 7

Replicant 7

Junior Audioholic
I’m clowning around but I’m prescibed medical THC oil and it works fantastic for several of my ailments.
.
I'll be by your way in a few days! I got something for you!! :) plus I want to checkout your new sub!!
 
Replicant 7

Replicant 7

Junior Audioholic
Pretty sure if I pulled this on my buddies, they'd make it real for me....and then be sad..hopefully
Not if it really happened, than they found out you really was dead. And when they walked back in your room and found you sitting up. It does happen you know. No pulse no heartbeat they pronounce you dead. The orderly comes to get you to go put you on ice and all of a sudden you sit up!!! :) It was my neighbor that I found died. Found him dead in his bathroom two Thursdays ago. Not a good thing to walk in on. But yeah he is dead, heart or something. Poor dude was bent over his head was on the toilet seat right hand was in the toilet blood all over his toilet. Looked like he was trying to sit down on the edge of the tub, right next to the toilet, small bathroom. His walking cane was standing up in front of his toilet bathroom laboratory was running over with water. He was cold. Thing is I saw him that morning sitting outside on his front porch. Just about everyday like clockwork 8am till 5 pm he would be in and out sitting on his front porch. I called 911 took them over 15 minutes to get to the address. Here's the thing about that, city Police station is like 1 1/2 miles from where I live. Anyways poor fellow I wasn't happy about the way they threw that old fella to the dogs. Had two Sons and I can count on one hand the times I've seen anyone go visit their father. Someone should have been staying with him. Just a sad sad thing in my book.
 
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Verdinut

Verdinut

Audioholic Ninja
With the box and port that I have where would you set the high pass? Btw got the Dayton dsp amplifier back in service. I somehow pinched and cut my input rca. That being said I now have 20/25/30 hz options not sure what the slope is though.
What is the exact net internal volume of your box, taking into account the volume taken by the driver and the space taken by the pipe? With that info and a confirmation of the pipe length, I assume that there is an elbow in your duct, I would be able to calculate the approximate tuning frequency.

The high pass filter should be set at a frequency which is not to be lower than the box tuning frequency. Below the tuning frequency, the sub is no longer loaded and therefore unprotected from cone displacements in excess of its maximum safe limit (Xmax). I'm surprised that the Parts-Express rep did not talk to you about high pass filtering. Did he mention what would be the box tuning frequency after the modification?

As for myself, I have never used high pass filtering on any woofer that I used. I don't play music or movies at very high SPL, so the question never occurred in my mind.
 
CajunLB

CajunLB

Senior Audioholic
Par
What is the exact net internal volume of your box, taking into account the volume taken by the driver and the space taken by the pipe? With that info and a confirmation of the pipe length, I assume that there is an elbow in your duct, I would be able to calculate the approximate tuning frequency.

The high pass filter should be set at a frequency which is not to be lower than the box tuning frequency. Below the tuning frequency, the sub is no longer loaded and therefore unprotected from cone displacements in excess of its maximum safe limit (Xmax). I'm surprised that the Parts-Express rep did not talk to you about high pass filtering. Did he mention what would be the box tuning frequency after the modification?

As for myself, I have never used high pass filtering on any woofer that I used. I don't play music or movies at very high SPL, so the question never occurred in my mind.
Parts express told me it’s about a 25hz tune. I also rarely listen louder than -20 so I shall experiment with high pass off then 20/25hz if think or hear that I need it. Got to say though I never saw that driver move so much when it was sealed and there is definitely more spl under 35hz witch is what I wanted so I’ll be happy and satisfied when it’s buttoned up.
 
lovinthehd

lovinthehd

Audioholic Jedi
Splain and/or remind me something Chris. As you know, back when the Snell plate amp failed, I tried a few different amps to passively re-power the ported sub. I tried the Crown because I liked the crossovers built in, but ultimately went with an Outlaw 2200 with my Denon AVR-X3300 providing LP crossover control . Am I missing something, or should I also have some sort of HP limiting to protect the sub?
I don't recall why you didn't use one/need one, but if you haven't needed one so far you probably don't need one now. Some ported designs can benefit from a protective hpf below their tuning point, tho depends on your use (as to what levels/frequencies) somewhat too....
 

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