Scrapwood Bandpass

[SpeakerBoy 64]

We found a huge pile of scrap plywood, and said hey, we could sure use more bass =P

It is ~1.3cuft sealed and the ported section is 12.5 cuft before displacements.

It is an 8ohm aspire audio 10" subwoofer. We are picking up a bash 300w amp by the end of the month.

Tuned to 28hz.

Me in the box....

Inspiration for the project =P

Super sweet port ends.

Catt says: "I do believe that this right here, this is a subwoofer"

Long day =)

I found the bass....yes......in here.....

The first two members of Lurking Skarred

Edited September 12, 2011 by SpeakerBoy

[The Catt 0]

I already love this thing... Lol finishing up today after I get back from my last class!!

[SpeakerBoy 64]

The sub:

Nowhere near enough port area.

Edited September 12, 2011 by SpeakerBoy

[///M5 2,833]

Gonna sound like utter crap

[SpeakerBoy 64]

Gonna sound like utter crap

Ouch, straight to the point eh?

Well, it is a scrapwood box. Nothing teaches like experience =P We are still getting a feel for the tools. The box for the blazer will be the first real test. Til then, it's practice.

We've spent less than a hundo on the whole project, so its not like we lost anything here.

[S.DeYoung 967]

How did you come up with those figures?

[The Catt 0]

Correction: We haven't spent any money at all.. So even if it does sound like crap, at least you can't hear it from your house! xD

[///M5 2,833]

Experience would be to understand what the different volumes of the box will do and tuning. Looks like you forgot that step which is exactly why its going to sound like crap.

[SpeakerBoy 64]

How did you come up with those figures?

I gotta remeasure, I lost my papers. Its 22" x 31.5" x 40" external - 3/4" ply

the chamber inside is 15.5" x 17.5" x 6.5" - 1/2" mdf

Actually I gauruntee it's off, because I rounded when I drew it out.

We can still cut the ports to length; we have four 2.5ft sections to work with. The box is for low low end. If we can get it to peak around 28-30hz, that's perfect.

[SpeakerBoy 64]

Experience would be to understand what the different volumes of the box will do and tuning. Looks like you forgot that step which is exactly why its going to sound like crap.

I have always just learned better by doing something myself and seeing what isn't working right, then adjusting and tweaking it til it is good. This isn't supposed to win any awards, it's us learning. So be nice

Some advice on future projects would be more helpful than telling me what I already guessed about this one.

Other than calculating box size/port length is winISD useful?. Are the graphs accurate? i've heard good things and bad about them.

Edited September 12, 2011 by SpeakerBoy

[///M5 2,833]

Advice:

1) Understand standard 4th order ported before attempting to design a bandpass

2) Design before you build

3) You won't learn by doing if you don't understand what you did

4) WinISD is very useful, even moreso if you've read the Loudspeaker Design Cookbook

[SpeakerBoy 64]

Advice:

1) Understand standard 4th order ported before attempting to design a bandpass

2) Design before you build

3) You won't learn by doing if you don't understand what you did

4) WinISD is very useful, even moreso if you've read the Loudspeaker Design Cookbook

I've been looking all over for that book, the Borders by us doesn't carry it; where can I pick up a copy?

[SpeakerBoy 64]

Advice:

1) Understand standard 4th order ported before attempting to design a bandpass

2) Design before you build

3) You won't learn by doing if you don't understand what you did

4) WinISD is very useful, even moreso if you've read the Loudspeaker Design Cookbook

Seeing as we already have most of it built and the ports havent been cut yet, we can still mess with the tuning. we have four 4" sections of pvc pipe, each 2.5' long. I know you know a shitton more than i do about this, so how about throwing us a few tips to steer us in the right direction?

Basically, all we are looking for is stupid low end on our slowed/chopped and screwed collection. Our goal is to peak a tad under 30hz.

[Shogen 325]

Advice:

1) Understand standard 4th order ported before attempting to design a bandpass

2) Design before you build

3) You won't learn by doing if you don't understand what you did

4) WinISD is very useful, even moreso if you've read the Loudspeaker Design Cookbook

I've been looking all over for that book, the Borders by us doesn't carry it; where can I pick up a copy?

AMAZON

[///M5 2,833]

I've been looking all over for that book, the Borders by us doesn't carry it; where can I pick up a copy?

Did you actually search ANYWHERE?

http://www.amazon.com/Loudspeaker-Design-Cookbook-Vance-Dickason/dp/1882580478/ref=sr_1_1?ie=UTF8&qid=1315855920&sr=8-1

Basically, all we are looking for is stupid low end on our slowed/chopped and screwed collection. Our goal is to peak a tad under 30hz.

The a 4th order BP is stupid and one that is poorly designed is asinine.

[SpeakerBoy 64]

I don't have a debit card

So buying online isn't an option as of right now. I know I can google it -.-

[SpeakerBoy 64]

I've been looking all over for that book, the Borders by us doesn't carry it; where can I pick up a copy?

Did you actually search ANYWHERE?

http://www.amazon.com/Loudspeaker-Design-Cookbook-Vance-Dickason/dp/1882580478/ref=sr_1_1?ie=UTF8&qid=1315855920&sr=8-1

Basically, all we are looking for is stupid low end on our slowed/chopped and screwed collection. Our goal is to peak a tad under 30hz.

The a 4th order BP is stupid and one that is poorly designed is asinine.

Quite literally, we can still make it a 4th order vented and scrap the bp idea. But what would we be gaining?

[the727kid 1]

Pay cash for a Visa gift card and order the book.

[SpeakerBoy 64]

Pay cash for a Visa gift card and order the book.

I didn't even....what....lol.

Gettin' on it.

[///M5 2,833]

I've been looking all over for that book, the Borders by us doesn't carry it; where can I pick up a copy?

Did you actually search ANYWHERE?

http://www.amazon.com/Loudspeaker-Design-Cookbook-Vance-Dickason/dp/1882580478/ref=sr_1_1?ie=UTF8&qid=1315855920&sr=8-1

Basically, all we are looking for is stupid low end on our slowed/chopped and screwed collection. Our goal is to peak a tad under 30hz.

The a 4th order BP is stupid and one that is poorly designed is asinine.

Quite literally, we can still make it a 4th order vented and scrap the bp idea. But what would we be gaining?

Output and response, but if you can design a 4th order then you'd know that. Add to that you'd gain EVERYTHING since a poorly implemented BP is terrible.

[SpeakerBoy 64]

I've been looking all over for that book, the Borders by us doesn't carry it; where can I pick up a copy?

Did you actually search ANYWHERE?

http://www.amazon.com/Loudspeaker-Design-Cookbook-Vance-Dickason/dp/1882580478/ref=sr_1_1?ie=UTF8&qid=1315855920&sr=8-1

Basically, all we are looking for is stupid low end on our slowed/chopped and screwed collection. Our goal is to peak a tad under 30hz.

The a 4th order BP is stupid and one that is poorly designed is asinine.

Quite literally, we can still make it a 4th order vented and scrap the bp idea. But what would we be gaining?

Output and response, but if you can design a 4th order then you'd know that. Add to that you'd gain EVERYTHING since a poorly implemented BP is terrible.

That's the kind of answer I was looking for =P

We are gonna try it as is, and then as a regular ported. We would go straight to ported, but there just something about going this far with it and changing directions that's no good. Just wanna say that we did both

Are the Radioshack SPL meters accurate enough to use it to compare this BP to the vented, and see what we gained, as well as what effect tweaks have on the box?

[Quentin Jarrell 671]

Who gives a flying fart what it's going to sound like. The only way to keep the industry alive is people like you enjoying the hobby.

It sounds like y'all are having fun playing around with a new setup and wanted to share with everyone. I dont know why anyone would want to scoff at that. And any one mature enough should realize this and be encouraging.

[steveo50 3]

Who gives a flying fart what it's going to sound like. The only way to keep the industry alive is people like you enjoying the hobby.

It sounds like y'all are having fun playing around with a new setup and wanted to share with everyone. I dont know why anyone would want to scoff at that. And any one mature enough should realize this and be encouraging.

i like his answer!

[Freshh 11]

Agreed! Hands on wood working and seeing the results is always fun! What's there to lose?

[CrownVic 15]

Agreed! Hands on wood working and seeing the results is always fun! What's there to lose?

Fingers?