Flex Your PCD Mettle:

[Pete Schumacher]

Re: Flex Your PCD Mettle:

sounds like a fun and exciting opportunity. also sounds like they cancelled your position prematurely

*best of luck!

and I look forward to what you see port wise for this thing with that internal volume

Thanks. By the way, I was born in Lawrence!

[jayhawk785]

Re: Flex Your PCD Mettle:

sounds like a fun and exciting opportunity. also sounds like they cancelled your position prematurely

*best of luck!

and I look forward to what you see port wise for this thing with that internal volume

[Pete Schumacher]

Re: Flex Your PCD Mettle:

last day at work--i've always hated when i give my notice and they actually make me work it. Love it when companies pay you the two weeks and send you on your way

I was notified back in March 2010 that my position was no longer needed, and was given an 11 month severance package. A few months later, they hired me back for a contract stint with another internal group. That ended last August. In November, they called me back again. That stint ends tomorrow, and the severance picks up again.

Now, it's on to full time speaker building and audio work in general with Vapor. May even be "repping" Arte Forma gear soon. Been dreaming about doing this next phase for most of my adult life. I'm both excited and apprehensive for obvious reasons, but I'm teaming up with some very gifted folks and have very high hopes.

Wish me luck!!! ;)

[jayhawk785]

Re: Flex Your PCD Mettle:

If you have EQ available, you can port even that smaller enclosure and extend the bass into the upper 30s with the right tune (as Zilch mentioned).

Without EQ, you won't be reaching into the 40s, and you have to be careful of tuning too high and getting a peaky bass response.

When I get home from my last day at work here, I can run a sim on the posted TS specs and see what happens.

that'd be fantastic.

per the eq recommendations, is that completely in lieu of a passive crossover?

adding a couple mini dsp's to do it is what I'd be doing instead? I'd be completely out of my element there, I can follow directions and handle the woodworking side--but the crossover design and tweaking is over my head.

I could cut open the bottom and add another chamber for another cubic foot or so, it wouldn't set these guys up to high. they'll be behind a screen so im not overly concerned that they look living room worthy

last day at work--i've always hated when i give my notice and they actually make me work it. Love it when companies pay you the two weeks and send you on your way

[Pete Schumacher]

Re: Flex Your PCD Mettle:

Pete, I've already created the boxes--my concern is the port/no port at this point. I created them about as large as I could with maintaining the baffle width of the PE box.

My interior volume is 1.77604cu ft. Slightly larger than a PE box. I'll try to find the winisd file for the 3012lf driver, but even then id like input on what you guys think in terms of port no port with that box size.

If you have EQ available, you can port even that smaller enclosure and extend the bass into the upper 30s with the right tune (as Zilch mentioned).

Without EQ, you won't be reaching into the 40s, and you have to be careful of tuning too high and getting a peaky bass response.

When I get home from my last day at work here, I can run a sim on the posted TS specs and see what happens.

[jayhawk785]

Re: Flex Your PCD Mettle:

I don't have the modeling software handy at the moment, but a guess, looking at the numbers, you'd need a cabinet of roughly 3cf, with a port tuning around 42Hz, which should give you F3 in the mid 40s. You could probably get away with a 3" diameter flared port. Port length? That's a guess I couldn't make with any confidence.

Zilch talked about using an EQ to handle the low end in the knockdown cabinet. If you don't want to use EQ, then a larger cabinet is definitely in order, as in a floor standing tower with the same footprint as the knockdown cabinet.

Pete, I've already created the boxes--my concern is the port/no port at this point. I created them about as large as I could with maintaining the baffle width of the PE box.

My interior volume is 1.77604cu ft. Slightly larger than a PE box. I'll try to find the winisd file for the 3012lf driver, but even then id like input on what you guys think in terms of port no port with that box size.

[Pete Schumacher]

Re: Flex Your PCD Mettle:

Pete, that's basically my question--what's the right sized cabinet, and should it be ported or sealed? There's really no definitive answer, short of people using the parts express knockdown... which is around 1.6cuft.

And as far as porting, there doesnt appear to be anything suggesting for certain that it should or shouldnt be.

thanks for all the responses guys--appreciate it.

I don't have the modeling software handy at the moment, but a guess, looking at the numbers, you'd need a cabinet of roughly 3cf, with a port tuning around 42Hz, which should give you F3 in the mid 40s. You could probably get away with a 3" diameter flared port. Port length? That's a guess I couldn't make with any confidence.

Zilch talked about using an EQ to handle the low end in the knockdown cabinet. If you don't want to use EQ, then a larger cabinet is definitely in order, as in a floor standing tower with the same footprint as the knockdown cabinet.

[jayhawk785]

Re: Flex Your PCD Mettle:

The 3012LF should have no problem reaching into the 40s in the right sized cabinet.

Fs: 37Hz
Qts: .32
Vas: 3.8cf

Factor in the coil resistance, and Qts moves up, allowing even lower F3.

Pete, that's basically my question--what's the right sized cabinet, and should it be ported or sealed? There's really no definitive answer, short of people using the parts express knockdown... which is around 1.6cuft.

And as far as porting, there doesnt appear to be anything suggesting for certain that it should or shouldnt be.

thanks for all the responses guys--appreciate it.

[Pete Schumacher]

Re: Flex Your PCD Mettle:

The 3012LF should have no problem reaching into the 40s in the right sized cabinet.

Fs: 37Hz
Qts: .32
Vas: 3.8cf

Factor in the coil resistance, and Qts moves up, allowing even lower F3.

[jayhawk785]

Re: Flex Your PCD Mettle:

I was hoping for 40's/flat-ish to 50 would be nice...




there's the box construction. I have to go get some more mdf tonight --ran out of wood to doublebaffle--had some math issues

So, I should be ok with that volume--do i need to port it or just go sealed with some stuffing?

[fastbike1]

Re: Flex Your PCD Mettle:

How low do you want them to play? Pro drivers don't tend to go too low. Having simmed other pro drivers w/ similar specs, I would suspect you won't get much lower than the high 40's for F10.

Depth isn't too critical as long as the driver fits.

. . . -- using the kappalite 3012lh, do I need to port the box, or will it be fine stuffed/sealed?

. . .
Was a bit worried about depth, but I think they should be deep enough. Is there a necessary amount of clearance needed behind either driver? I think as is i should have 1-2" behind either.


THanks-
steve

[NEO Dan]

Re: Flex Your PCD Mettle:

The roundover looks like it will be the "thing" that determines the distance between drivers, although you can always route into the flat edge of the WG.

[jayhawk785]

Re: Flex Your PCD Mettle:

Hey Super Steve,
You want to build using Z's deluxe crossover, but with Brandon's cab style? You have big round over bits?

I think I have 1.5 and 1.25 inch bits--possibly 1 inch...

But ya basically the same style, with the listed deluxe xover (since I have the parts already on the way)

I'll post a picture of the cabinet progress tomorrow -- not that the square boxes are exciting

[NEO Dan]

Re: Flex Your PCD Mettle:

Hey Super Steve,
You want to build using Z's deluxe crossover, but with Brandon's cab style? You have big round over bits?

[jayhawk785]

Re: Flex Your PCD Mettle:

I've begun building the econowave - deluxes, all speakers/waveguides and crossover parts should be here mon/tuesday.

I started building the boxes, i made them a bit narrower to fit behind my screen.

dimensions are 17wx25.5hx10.5d (double baffle - woofer recessed to second piece, and opening rounded over) -- using the kappalite 3012lh, do I need to port the box, or will it be fine stuffed/sealed?

I've read as much as I can in here and other forums--hoping the boxes will be ok as I've made them. Was a bit worried about depth, but I think they should be deep enough. Is there a necessary amount of clearance needed behind either driver? I think as is i should have 1-2" behind either.

I appreciate any help guys--I never had a chance to know or speak with Zilch and after reading so many threads with his name in it and all the time he's put into this project, I was saddened to hear of his passing.

THanks-
steve