Beach Radio v5! (Sealed 3015LF sub)

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Hey I was gunna, but now I found a use for it lol

Those two Beta 8As are going to be so much louder than the Kappalite in a sealed cabinet that I think you're gonna run out of power on the thing trying to keep up. However, if you model it a vented cabinet with a short vent to increase its passband efficiency (at the expense of extension of course), it might work out quite good.
 
Yeah I know. Because they kept up just fine with 600rms and the two ss15's I had them paired with (300rms each ss15)

But It's all at the cost of size and portability.

Ill see if I can shove a port in there somewhere. But if its too small I'd rather just do sealed as opposed to having a port chuff noise all the time :(
 
...because they'll make the box heavier than it needs to be? :)

So I thought long and hard for a reason not to use the Pyle midranges, besides just a weight increase.

And I have come up with the following reasons not to use them, and just use the beta8's crossed to the tweeters.

-I can bridge the amp and let the passives take care of crossover duty. Still high pass at 120hz via the head unit, or at the amp itself.
-More Volume for the subwoofer enclosure, more output.
-efficiency is the name of the game when running off battery power, and since a horn loaded subwoofer is out of the question, I should really be using a ported subwoofer enclosure for a few more db in the passband. Without the Pyle midranges in the way, and with a little more volume, I can come up with something useful (two 3" ports)


I'm thinking of tuning slightly above 30hz, because A that's the only high pass option I have to protect the sub from over excursion (amp has selectable 15/30hz high pass) and B. a lot of the EDM has content in the 35-40hz range.

I'm going to run some sims and see what tuning I can come up with with the two 3" ports and my current projected enclosure volume. I did some rough calls and I have about 2.41 ft^3 before driver displacement and port tube displacement.

Ohh and the Beta8's will be run sealed in .40 ft^3 enclosures.
 
The basic layout of the box now that I will be crossing the beta 8's right to the tweeters. The waveguide of the tweeters actually separated from the driver, I will try and epoxy them back together

imagevxk.jpg


Started cutting, cut the top 18mm birch baffle and got started on making some holes
imagebpk.jpg


Laying out the midrange spacing
imagezkg.jpg
 
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Yeah I know. Because they kept up just fine with 600rms and the two ss15's I had them paired with (300rms each ss15)

But It's all at the cost of size and portability.

Ill see if I can shove a port in there somewhere. But if its too small I'd rather just do sealed as opposed to having a port chuff noise all the time :(

Project looks fun and it is a good idea to ditch the Pyles but how do you pull that much current from the PDX?

It is rated 600-700watts at 2 ohms, 1/2 that at 4ohms = around 350 and 1/2 that at 8ohms is 175.

Am I missing something?

I would not tune it below 50hz btw.
 
Is a regulated amp (1-4ohms) And the 8ohms is the nominal Re is 5.3 I believe?

The birth sheet on the amp was 692rms. I know that's at 14.4 volts but still higher than rated. So I figured my estimate of 300rms in the passband is fairly close.

Also, if I don't tune close to 30hz, like 35ish, then the speaker could be damaged if someone just blasts the radio and ignores the distortion etc
 
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Also, if I don't tune close to 30hz, like 35ish, then the speaker could be damaged if someone just blasts the radio and ignores the distortion etc

What sort of filtering options does the deck have? You could tune the cab to have a peak at Fb, then set the deck to feed the sub with a signal that's high-passed at or near Fb. This should flatten the passband response and eliminate the possibility of over-excursion below Fb.
 
What sort of filtering options does the deck have? You could tune the cab to have a peak at Fb, then set the deck to feed the sub with a signal that's high-passed at or near Fb. This should flatten the passband response and eliminate the possibility of over-excursion below Fb.

That's just it, I can't set any "subsonic" filter with the pioneer head unit. It will only allow you to high pass the non sub channel. And that is only selectable from 80-120hz I believe.

The alpine PDX amp just has a simple 15/30hz subsonic filter switch on it. So If I'm not going the sealed route I'd have to do the 30hz filter.

I think it was not a problem before because the ss15 throat added some compression
 
Yeah sorry if that wasn't clear. I waiting on getting another sheet of 1/2" Baltic birch.

And I was planning on removing some of the inner liner, where it sort of steps inward. I do not want to ruin the integrity of the outside of the cooler and the built in plastic handles, so I won't really be modding the outer blue plastic too much.
 
No signal current draw at 12V. If it's specified at 14.4, it'll be somewhat proportionally higher at the lower voltage because of switching regulator action. Also, glad to see the Pyles go. They might beam less at top frequency, but by the time you get 100hz above the resonant peak, you'd probaby be at around 500 Hz or so on the bottom... Shame not to let the 8A's handle that, and maybe a few more octaves..
 
Yes, it only matters if the amps are live, but it's important because it means no matter what you're playing, you're drawing at least that much current. It sets a hard upper limit on battery uptime. Throw in head unit load as well. All together you might have somewhere between 5 and 10 Amps. It would be handy to know exactly.
 
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