Titanic 10" T/S HELP!!

[gregm]

Hi all--

I've had a Titanic 10" Kit for a while, and I started tinkering with it. First thing I did was measure the T/S with Speaker Workshop and the Wallin Jig. I got wierd results, Fs=40Hz and Qe=0.65 in free air. I contacted PE, sent back the old driver, and they sent me a new one. I tested it when I got it. Basically the same results. This concerns and confuses me. I've got some B3S's and NSB's that come pretty darn close to the published T/S.

I'm testing it with an output level equal to the max output of my soundcard (+4 dBu). The Wallin Jig has a ~8 Ohm series resistance, for those not familiar with it.

Do I need to test at a higher level? A lower level? Anybody out there with a 10" Titanic that you've measured the T/S on?

Anybody in the Portland,OR/Vancouver,WA with a test setup who's willing to double-check my measurements?

I really want to make sure that I'm not doing anything wrong, and then I'll decide how I want to deal with PE. Shipping from Portland to Dayton ain't cheap, especially for a 10" sub. And I've done it once already...

Thanks all--

Greg

[shawn_a]

I've got a MkIII sitting here staring at me that I've tested but the data was corrupted during a computer issue I was having. If you have the MkIII which I think you do, I will measure it up and post the results for your comparison.

shawn

[shawn_a]

Re = 3.02 Ω
Fs = 37.5 Hz
Qes = .46
Qms = 4.76
Qts = .42
Le = 2.33 mH
Vas = 20.5 l
Dd = 193 mm
Sd = 292.5 cm^2
Bl = 12.81 N/A
Cms = 170.5 µm/N
Kms = 5866 N/m
Mms = 105.8 g
Sens = 89.8 dB (2.83V/1m)
Eff = .227%
Rms = 5.23 Ω

These measurements were taken on the WT2 software v1.04. The ambient temp is 62˚F so I don't think that's a factor. I do wonder if the specs for the Titanic were derived using a larger signal than the WT2 can currently supply.

shawn

[gregm]

Both versions of the Titanic I had (old one and new replacement) were Mk. III.

Those numbers are pretty close to what I have (my Qes is higher). But like I said I was testing with an output level of ~1.2Vrms. With an 8Ohm series resistor, that means the driver should have been seeing ~0.4Vrms.

It'll be a few days before I get a chance to test again, but I'll try in with a higher drive level and some attenuators so I dont destroy my sound card.

Anybody from PE know the test conditions for measuring the Titanic Mk. III 10" T/S?

--Greg

> Re = 3.02 Ω
> Fs = 37.5 Hz
> Qes = .46
> Qms = 4.76
> Qts = .42
> Le = 2.33 mH
> Vas = 20.5 l
> Dd = 193 mm
> Sd = 292.5 cm^2
> Bl = 12.81 N/A
> Cms = 170.5 �m/N
> Kms = 5866 N/m
> Mms = 105.8 g
> Sens = 89.8 dB (2.83V/1m)
> Eff = .227%
> Rms = 5.23 Ω

> These measurements were taken on the WT2
> software v1.04. The ambient temp is
> 62ËšF so I don't think that's a factor.
> I do wonder if the specs for the Titanic
> were derived using a larger signal than the
> WT2 can currently supply.

> shawn