28 Days Later

[kees52]

I did sim the visatons wideband speaker 3.3 inch. FRS 8 M high force factor (big magnet).

I did want to make a BLH with it, but do not now if a qts of 0.49 is to high
for a BLH, it looks so it is. Speaker is so cheap, it works also in a synergy
I did see. It is so that the speaker is very close is to the throat, and give to 3 Khz output, maybe a little to close.

regards

 

[Flaesh]

beautiful pic!
kees52, can you post input page screen?

 

[GM]

I did want to make a BLH with it, but do not now if a qts of 0.49 is to high for a BLH, it looks so it is.

No, it takes a 2.0 Qts to have no BW to box load, at 0.49 Qts a ~36-431 Hz box loading BW is doable, though such a long path-length may prove impractical. It maybe better to raise Qts a bit to shrink this BW a bit.

GM

 

[Beau]

No way you will get the taps in that close to the throat, need to go further out and that will kill your top end response.

 

[Patrick Bateman]

An externally hosted image should be here but it was not working when we last tested it.

Gento SP99023A, $2

Thiele Small (measured vs published)
fs) 201.9 vs 333.8(!)
qts) 0.73 vs 1.17(!)
qms) 3.0 vs 4.93(!)
qes) 0.96 vs 1.54(!)
re) 3.64 vs 3.56
le) 0.25 vs 0.26

horn bandwidth (guesstimate) = 202-420hz

The measurements from Parts Express are so far off, it really makes me wonder if they measured a different driver. (2" Paper Cone Midrange Tweeter 4 Ohm 289-127) I have a whole box of these (for two bucks, why not?) and the consistency from driver to driver was very good, within about 3%.

My WT2 died, and I bought a DATS. It looks like my measurement of the Gento, that I did with my WT2, was incorrect. Here's what I'm getting with DATS:

Thiele Small (published vs measured)
fs) 201.9 vs 207.3
qts) 0.73 vs 0.8
qms) 3.0 vs 3.16
qes) 0.96 vs 1.07
re) 3.64 vs 3.5
le) 0.25 vs 0.1

So either I measured a bad one (I have a whole box) or my previous measurement was bad. It looks like the published measurements are pretty accurate.

 

[sethalump]

Go figure, the top google hit for this random driver marked "GENTO SP99023A" that I purchased a bunch of years ago..... and I run into you. Apples fall only so far.

Thanks for saving me from having to bust out that DATS thing (that I've never opened)

Either way... even more reason to fart around with building some speakers + CAD practice + warm up the CNC machine.

 

[Patrick Bateman]

Go figure, the top google hit for this random driver marked "GENTO SP99023A" that I purchased a bunch of years ago..... and I run into you. Apples fall only so far.

Thanks for saving me from having to bust out that DATS thing (that I've never opened)

Either way... even more reason to fart around with building some speakers + CAD practice + warm up the CNC machine.

Ha! Just stumbled across this post.