Dayton WT3 Speaker Tester

[Pano]

Great minds think alike.

[vinnie]

Hi, I just received my WT3 and first I wanted to test some 15" car woofers I had laying around.
The spec sheet that came with the driver says that mms is 126g, so to measure vas I started with adding 100g in the middle of the cone, driver standing horizontal. Now I got the msg that the added weight was to small, so I added more and more....and more, until the added weight was 344g.
As you can see in the attached file, WT3 says that this driver has a mms of 392g.
I also tried with the driver standing vertical, then mms is measured to 402g.
This driver has a very stiff rubber surround, could that throw off the results? Spec sheet says Cms is 217.7 Um/n
Im gonna try and make a test box and see if it gives different results.

BTW, this is a dual voice coil, and Im measuring both at the same time, connected in series.

[Loren42]

Originally Posted by vinnie

Hi, I just received my WT3 and first I wanted to test some 15" car woofers I had laying around.
The spec sheet that came with the driver says that mms is 126g, so to measure vas I started with adding 100g in the middle of the cone, driver standing horizontal. Now I got the msg that the added weight was to small, so I added more and more....and more, until the added weight was 344g.
As you can see in the attached file, WT3 says that this driver has a mms of 392g.
I also tried with the driver standing vertical, then mms is measured to 402g.
This driver has a very stiff rubber surround, could that throw off the results? Spec sheet says Cms is 217.7 Um/n
Im gonna try and make a test box and see if it gives different results.

BTW, this is a dual voice coil, and Im measuring both at the same time, connected in series.

The optimal goal is a shift of 25% of the Fs of the driver to measure Vas.

Typically 30 to 100 grams is al you need, but never more than the mass of the original cone.

Also, errors for Vas are not uncommon nor represent a big problem in the end.

Doing both added mass and closed box Vas testing is a good tact. Just make sure there are no leaks in the box. Even so, leakage past the driver's vent will affect the results slightly.

[doug20]

Originally Posted by hasselbaink

Concerning Dayton WT3 and Windows Vista ! ! !

I know some of you might have had problems running WT3 on Vista (which is a piece of sh*t software if there ever was one). The manufacturer Dayton has added instructions for vista and sound settings must be according to specifications for each USB port. Now, as I've metioned: Vista really stinks up my computer so I decided to get rid of some of the bandwidth wasting services/features and disabled a lot of them. So my PC ran more or less acceptable, however when I installed WT3 the unit would work just about long enough to calibrate then show a garbled graph. I would unplug the unit then re-attach it, calibrate and 5 seconds later = garbage. This caused me no end of grief since the unit would work for a few minutes then crash. Actually the graph would end up looking like it was measuring the wrong codec (soundcard).
As I have hinted the problem is the performance tweaks on Vista. Anyone having issues with the WT3 should make sure that all services that have anything to do with audio or USB should be running. What I did, was I created a new account exclusively for speaker measurement and turned on most of the services by running the services.msc command. Finally WT3 works - Don't make the mistakes I did!

Perhaps this topic merits it's own thread. I let the admin decide.

Best
Kris

I have never had an issue with Vista. Sorry to read about yours.

I know I had to make sure I set my recording to 2 channel 41K bit but that was it.

[Kjeldsen]

Originally Posted by planet10

Mike,

You have to be very careful making a statement like that. T/S parameters aren't scalar numbers, they are at least f(V) curves in 2-space.

Indeed. I remember som DIY'ers in a danish forum, also claiming that manufactur spec's was wrong by a fair margin. But, when a pro-engineer joined the discussion, and giving advice on how to measure correctly, suddenly the DIY'ers came close to the official specs.

[theAnonymous1]

PCM2900B
TPA6111A2
LMV358

That's all I'm sayin'.

[theAnonymous1]

Anyone else with a WT3 upgrade to the V2.0 software? It now includes a "rub and buzz" test feature along with LCR measurment functions.

[fatmarley]

Originally Posted by theAnonymous1

Anyone else with a WT3 upgrade to the V2.0 software? It now includes a "rub and buzz" test feature along with LCR measurment functions.

I haven't used the "Rub & Buzz" test but I've found the LCR tests very handy to check parallel or series resistors and for unwinding or winding inductors. I think it's good practice to measure components, even if the value is printed on the side.