my tuning freq......part 2

[jonnybusa 10+ year member]

OK.......I got all kinds of help on trying to figure out my tuning frequency of my box, and couldnt figure anything out w/ the formula's I got from some members.

Well, the moderator @ "realm of excursion" finally told me the formulas wont work on my snailshell box for some reason.....I guess its because the port is most of the box.

So now I ask if anyone knows how, at all, I can figure out the tuning frequency of a snailshell box. its loud as hell, but I would kinda like to know some things about it as well.

Pic............

so you can kinda see the internals of the box, and how the port is actually most of the box.

Anyone have a clue????

thx

Click to read more...

 

[sku 10+ year member]

Play a tone sweep and note which frequency(s) move the cone the least.

 

[Death By Bass 10+ year member]

Play a tone sweep and note which frequency(s) move the cone the least.

also, measure the impedance.... the point where the impedance peaks, would be the tuning frequency...

however, this may not work too well...

but, worth a try anyway //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[jonnybusa 10+ year member]

also, measure the impedance.... the point where the impedance peaks, would be the tuning frequency...
however, this may not work too well...

but, worth a try anyway //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

****.....I'll try the 2 above ideas, but thought there was just another formula to use. Maybe I'll just try out a few more boxes to get it a little louder......just wanted to get some info to build on, to make changes w/ the new boxes I make.

I dont wanna just make another snailshell, and just change the port size or layout......prolly just a waste of time and MDF.

 

[Immacomputer 10+ year member]

Actually cone control and impedance won't be very good measurments of the tuning.

If you want a rough estimate, measure the length of the red line on your enclosure:

Come back with that and I'll tell you about what it's tuned to. This will be pretty rough though and won't be exact. The enclosure is very similar to a horn/tl enclosure and it does not work the same way as a ported enclosure. Although this design is different, it's still very similar and still involves quarter-wave theory.

 

[Thnking 10+ year member]

It's a transmission line with an increasing vent area, as opposed to a decreasing vent area used in a standard transmission line.

There is no simple formula to plug numbers into. There are going to be multiple resonances...your best bet is either to read up on transmissins lines (a lot of time and complicated math), or just build a more simple box, like you're suggesting.

 

[Death By Bass 10+ year member]

Actually cone control and impedance won't be very good measurments of the tuning.
If you want a rough estimate, measure the length of the red line on your enclosure:

Come back with that and I'll tell you about what it's tuned to. This will be pretty rough though and won't be exact. The enclosure is very similar to a horn/tl enclosure and it does not work the same way as a ported enclosure. Although this design is different, it's still very similar and still involves quarter-wave theory.

its not 1/4 wave, its way too short, hence my reasoning that its actually acting just like a ported box... as I pointed out on the Nolte Audio forum, and got all my posts deleted... lol

some poor guy was doing like 140dBs with two 15's or something

 

[jonnybusa 10+ year member]

its not 1/4 wave, its way too short, hence my reasoning that its actually acting just like a ported box... as I pointed out on the Nolte Audio forum, and got all my posts deleted... lol
some poor guy was doing like 140dBs with two 15's or something

well, I tried to contact nolte, and got no responses. I love this box.....even recently hit 145db on a tl w/ it, just wanna see if changes in freq will give a little more. I'd rather do another snailshell because w/ only around 1600rms watts going into my XXX 15, I doubt a regular ported box will get me above, or even to 145db. w/ such low power.

 

[Immacomputer 10+ year member]

its not 1/4 wave, its way too short, hence my reasoning that its actually acting just like a ported box... as I pointed out on the Nolte Audio forum, and got all my posts deleted... lol
some poor guy was doing like 140dBs with two 15's or something

While it may be short, the idea is still based on quaterwave and line theory. It also has similar characteristics of a ported enclosure though. I'm pretty sure an enclosure like this won't have a steady turning frequency but rather one that changes with the frequency. I think the lowest point though would be the line length but that doesn't mean it won't play lower as the vehicle cabin will have a large effect on that as well.

 

[jonnybusa 10+ year member]

While it may be short, the idea is still based on quaterwave and line theory. It also has similar characteristics of a ported enclosure though. I'm pretty sure an enclosure like this won't have a steady turning frequency but rather one that changes with the frequency. I think the lowest point though would be the line length but that doesn't mean it won't play lower as the vehicle cabin will have a large effect on that as well.

ok.....so is the red line i have to measure the center of the port throughout???

i have black elec tape outlining the port from the outside, so i can measure what you need me to.

thanks

 

[Immacomputer 10+ year member]

Basically, but it's more than just what you might consider the port. Measure starting from the left of the sub magnet and get it down the middle of the line.

Again, this will NOT give you an exact and really though, the tuning doesn't even matter since it's already built. Why are you worrying about it so much?

 

[bk12321 10+ year member]

well, I tried to contact nolte, and got no responses. I love this box.....even recently hit 145db on a tl w/ it, just wanna see if changes in freq will give a little more. I'd rather do another snailshell because w/ only around 1600rms watts going into my XXX 15, I doubt a regular ported box will get me above, or even to 145db. w/ such low power.

I wouldnt really call 1600 low power for a xxx15, or even in general if we are talking about daily drivers

 

[jonnybusa 10+ year member]

Basically, but it's more than just what you might consider the port. Measure starting from the left of the sub magnet and get it down the middle of the line.
Again, this will NOT give you an exact and really though, the tuning doesn't even matter since it's already built. Why are you worrying about it so much?

I'm only worrying because I want to maybe make changes on my new box depending on what this box's specs are. I mean, this box helped hit 145db, and sounds incredibly quality wise......now how do I make a change for the better, of which change do I even make on a snailshell?? I figure if I can get a frequency, then knowing how, I can change the freq on the next snailshell I build.....make sense??

 

[jonnybusa 10+ year member]

I wouldnt really call 1600 low power for a xxx15, or even in general if we are talking about daily drivers

well, wen I posted my specs of my system, peeps on here gave me **** saying I was under powering the sub, and the amp was basically ****

so thats why I said "only 1600 watts"

 

[Immacomputer 10+ year member]

I'm only worrying because I want to maybe make changes on my new box depending on what this box's specs are. I mean, this box helped hit 145db, and sounds incredibly quality wise......now how do I make a change for the better, of which change do I even make on a snailshell?? I figure if I can get a frequency, then knowing how, I can change the freq on the next snailshell I build.....make sense??

There is much more to a properly designed horn/tl hybrid enclosure than just the frequency of the line. I'm not even sure what that enclosure really is. Did you design and build it yourself?