Ratshack Budget Subwoofer

[bickeler]

Hi all I thought I'd do little write up of my budget HT sub.

The drivers are the old Ratshack 15"s I picked a pair up for 35 off ebay.

I borrowed a PE tester and these arent anywhere near what the specs from RS say.

RS claimed a qts of .81 or something outlandish these are barely .40
maybe it's from use I dont know.

I plotted a sealed box with the .40 qts and a VAS of 12 and got a 4.5 cu ft box with an f3 of 35hz.

Not earth shakingly low but more than enough for HT.

The amp was scavenged from a 150w 12" KLH sub cost was 20 dollars used.

The rest was wood 3/4 Baltic Birch about 2 sheets of 4x3 ft .
Cost was about 30 including glue and screws.

The bafle is double thick 3/4 Birch. Sides are 1" MDF(The MDF came free hehe from old speaker racks.)

Total cost so far is well under 90 dollars.

Here a construction pic

Thats not the baffle thats the internal brace

[bickeler]

Here is the finished product

[bickeler]

And another

[bickeler]

one more

[woody]

Where did you get baltic birtch that cheap?

[bickeler]

Home Depot I live in Upsate Ny wood is fairly cheap here.I know when I went to NYC the prices were double from up here.

[CarlosT]

WOW...you certainly are frugal...

So how's it sound? Is it a sealed box? Is one of the drivers a drone? Looks like a hobo's Paradigm...

[bickeler]

It's sealed.No drone wired in parallel they are 8ohm drivers.

Thanks for the critique,actually it's not finished literally.

The baffle and top you are seeing are raw wood.

And I still need to countersink the woofers(I don't own a router and my 8" 2ways in another thread I did with a razor and chisel definitely not an easy task doing 2 15s.) and make a grill.

Sounds very good not too boomy with a lot of low bass for only a 150w amp.

I could compare this to any sub I've seen or heard for under 700 and they wouldnt hold a candle to this.

Sounds very accurate too listening to some old JP recordings where the bass is very subtle it does extremely well.

[ßart West-VL.]

Great!

I happen to have four of those drivers in my garage and have been wondering what the best sub for HT would be for a long time.
Would you mind posting the measurements you made, please?

In all honesty, I think the subs should play lower for HT. But that's not important if you're happy with them the way they sound now.

Bart.

[bickeler]

Here's what I have on the 15" Polycone foam surround RS woofer

150 watts rms

Qes .43

.Qts .40

VAS 11.96 Cu ft

SPL 91.2 1w@1m

Xmax 4.8mm

FS 24hz

8ohms nominal impedance

DC 6.2ohms impedance

I can't find the model numer its 40-1XXXXX lol I had it somewhere

Not as bad as I was originally led these drivers to be.I had passed on pair on clearance years ago.

anyway that should be enough to design a box it was for me.