Can I skip the crossover?

[xboxsamurai8]

I'm wondering if you could run a (Tang Band W3-1878 3" fullrange) without a low cut.

Here are the response graph and specs: http://www.parts-express.com/pdf/264-902s.pdf

I am planning to do this in a single driver ported box with QB3 alignment with an Fb=105 Hz, and an F3=128.7 Hz, just to clear anything up.

[Wolf]

Sure you can, but don't expect prodigious bass or output potential without one.

Later,
Wolf

[xboxsamurai8]

Sure you can, but don't expect prodigious bass or output potential without one.

Later,
Wolf

How does a lowcut help low end output?

[Sydney]

Relieved of the task of attempting to reproduce bass - the small driver doesn't hit excursion limits.
Just to maintain a desired SPL: Dropping frequency in half requires 4x the volume of air be moved - that means more excursion per driver and/or more drivers required.

[Wolf]

How does a lowcut help low end output?

I sort of meant that you can't have both. Wasn't as rhetorical as I thought...

It will keep the driver from overexcursing, therefore allowing more clean output other than what is cut. I know it has 4mm of Xmax, but that does not mean it's capable of subwoofer realizations, so if you have no low-cut, you'll be limited in the amount of output you can achieve before it starts to unload or complain.

I've used several of TB's offerings, and can't really complain about what they can do on a no-filter setup, but output and bass will be limited.

Later,
Wolf

[xboxsamurai8]

Relieved of the task of attempting to reproduce bass - the small driver doesn't hit excursion limits.
To maintain a desired SPL dropping frequency in half requires 4x the volume of air be moved - that means more excursion or more drivers required.

Are you talking about the fact that this speaker is in a ported box?

[Sydney]

Porting a cab does affect the excursion vs SPL curve, BUT it doesn't overcome the displacement requirements particularly below box tuning.

[lunchmoney]

How does a lowcut help low end output?

What he meant was that yes you can run it full range, but don't expect much bass out of it... and you're likely to encounter significant distortion when it attempts to hit bass notes, which will cause distortion across the entire range of the speaker...

So you're definitely better off high passing it and using a sub... not just for clean bass, but for clean mids and highs too.

[xboxsamurai8]

I sort of meant that you can't have both. Wasn't as rhetorical as I thought...

It will keep the driver from overexcursing, therefore allowing more clean output other than what is cut. I know it has 4mm of Xmax, but that does not mean it's capable of subwoofer realizations, so if you have no low-cut, you'll be limited in the amount of output you can achieve before it starts to unload or complain.

I've used several of TB's offerings, and can't really complain about what they can do on a no-filter setup, but output and bass will be limited.

Later,
Wolf

Ok got it, I was thinking of adding a 130uf capacitor in series with the speaker but the impedance of the speaker raises around the 150 Hz area that I want to started cutting at, would it be better to have a impedance eq or just raise the order of the cutoff?

[xboxsamurai8]

Porting a cab does affect the excursion vs SPL curve, BUT it doesn't overcome the displacement requirements particularly below box tuning.

So would you recommend using these in a seal cabinet?

[Sydney]

I'm guessing ( from a cursory peak at the T/S specs ) that it could be used in either sealed or vented.
A simple sealed does offer more tolerance of driver variation and tight motion control at the expense of a slow rolloff with less bass extension. A vented will get lower with a sharper cutoff but it's a design that requires tuning to work optimally.
That said I have run similar 4" vented tuned to 77Hz BUT I used a HP filter to block stuff below 77 Hz.

M.A. Step 1 & 2 would be to model it ( with thermal and displacement limited curves ) AND get feedback from those who have actual experience with this driver.
Either way I would count on cutting bottom bass to this driver as it is makes a better mid than bass driver.
Those bottom 2 octaves are tough.

[xboxsamurai8]

I'm guessing ( from a cursory peak at the T/S specs ) that it could be used in either sealed or vented.
A simple sealed does offer more tolerance of driver variation and tight motion control at the expense of a slow rolloff with less bass extension. A vented will get lower with a sharper cutoff but it's a design that requires tuning to work optimally.
That said I have run similar 4" vented tuned to 77Hz BUT I used a HP filter to block stuff below 77 Hz.
Step 1 & 2 would be to model it ( with an thermal and displacement limited ) curves AND get feedback from those who have actual experience with this driver.
Either way I would count on cutting bottom bass to this driver as it is makes a better mid than bass driver.
Those bottom 2 octaves are tough.

So I guess I'l stick with my ported design(It's tuned) and just add a highpass in the mix, thank you.

[Sydney]

That should work fine.