Altec 414 in sealed enclosure..

[Barossi]

Hi,

does anybody knowns the best volume for the 414 in a sealed enclosure? I will use them from up to ~75Hz. The Klipsch corner horn will manage the deep bass. Any ideas? What about open baffle for the 414? Does anybody have the TS-Parameter for the 414 16 Ohm on hand?

Greetings Barossi

[vuki]

Hi,

my 414Z's measured with Clio have following T/S parameters:
Fs 37 Hz
Qm 2,9
Qe 0,34
Qt 0,31
Mm 22 g
Vas 178 l
BL 14 N/A


regards,
Vuki

[GM]

Greets!

It depends on how much output impedance (OPI)your SET amp has and what Qtc you consider 'best'. For example, assuming a worst case OPI of 4 ohms and 0.7 Qtc, then ~69 L.

Yes, you can use it on an OB if it's big enough and/or close to a boundary, so perching them on top of corner horns might work.

GM

[GM]

Greets!

Thanks for the info! Do you have Re, Sd, Le?

TIA,

GM

[Barossi]

Hi Vuki,
thanks a lot for the T/S parameters! I spend some time using a very nice simulation tool called AJ-Horn. I would like to build a sealed enclosure with the 414. My dreams are:
2* sealed enclosures each 50 liters between them 1* 806a driver with 511b horn. A bit D'appolito style.

Here's my simulation with 50 l sealed and Vuki's parameters for the 414:



Looks like that this box has a very nice rolloff at ~60-70 Hz. I will then add a Klipsch corner horn!

Greetings Barossi

[vuki]

Re is 11,4R, Sd is ca. 500cm2 and Le at 1kHz is 3,28mH
Here is Altec 414Z in Petite Onken in room RTA measurement. Room is 4,8x6x4m, distance to mike is 2m. Huge peak at 40Hz is room mode.

[IMG][/IMG]

[GM]

Greets!

Thanks for the info! FYI, when I 'do the math' though, the numbers don't work out at all. BL calcs between 16.9317-17.0515 N/A and Mms 36.78-37.3 grams depending on the po/c used, too far off for them to be reasonably accurate.

GM

[GM]

Greets!

Unfortunately the numbers still don't calc 'close enough' based on 500cm^2 Sd and 11.4 ohms Re. BL calcs between 15.8874-16 N/A and Mms 33.6-34.08 grams depending on the po/c used. Wish I could offer some possible reasons for this, but my knowledge of CLIO is limited to that it's very accurate when everything's properly calibrated.

GM

[vuki]

Hi,

I used Sd 530cm^2. Are you sure 414's have Sd 500cm^2 ?

[GM]

Greets!

Based on -8C, -8E published Vd/Xmax: 11.8"^3/0.15" = 78.66"^2 = 507.5216 cm^2, though an old data sheet I have lists the -B at 78"^3 = 503.2248 cm^2, so this would be the 'window' IMO. I only used 500 cm^2 because it's what you listed. At 530 cm^2, BL calcs between 16.8406-16.9597 N/A and Mms 37.76-38.3 grams depending on the po/c used, so still too far outside the 'window'.

What po/C are you (it?) using? Based on experience, my 'window' is po =1.20997-1.21 kg/m^3, C = 342 - 344.424 m/sec unless spec'd otherwise.

GM