help measurin imp in soundeasy

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Jump to Latest
soongsc

soongsc

Member
Joined 2005
ravslanka said:
hi soongsc,

here are the screenshots with yamaha sound card

after calibration of sound card

withoud pulse delay
http://i44.tinypic.com/vo3ihh.jpg

with pulse delay
http://i43.tinypic.com/2ly0i6a.jpg

calibration scopes are these ok
http://i44.tinypic.com/34g0w8z.jpg

and with sampling rate of 96000
http://i44.tinypic.com/htzgw0.jpg

ravs
Click to expand...
Have you looked at the spec sheets of these two cards? I think they are only capable of doing 48KHz full duplex mode sampling. So setting at higher rates in SoundEasy don't really give you any benefits.

The Yamaha card seems to have the signals inverted. So if you wish to use that card, you need to go to the "preference" setting in SE to invert both data and reference inputs.
 
R

ravslanka

Member
Joined 2006
google.com
soongsc said:

Have you looked at the spec sheets of these two cards? I think they are only capable of doing 48KHz full duplex mode sampling. So setting at higher rates in SoundEasy don't really give you any benefits.

The Yamaha card seems to have the signals inverted. So if you wish to use that card, you need to go to the "preference" setting in SE to invert both data and reference inputs.
Click to expand...


hi soongsc,

these both cards are of year 1999-2001.supportig sampling rates of 48000.so shoud i go wth yamaha and start measuring the drivers.is everything ok now.and what is the cause of this probem .did you ever faced such problem.do i need to add an amplifier or use the sc amplifier.

thanks all you guys for all your support.

thanks

ravs
 
soongsc

soongsc

Member
Joined 2005
ravslanka said:
hi soongsc,

should i continue with the present settings ie rectangular window and pulse deay,or return to my previous settings with blackman window type and pulse delay and follow the normal procedure

ravs
Click to expand...
Personally, I always use the rectangular window. I like to let my brains do the filtering than the software. Other window types let you have neat looking cuves. I like to look at as much detail as possible.
 
soongsc

soongsc

Member
Joined 2005
ravslanka said:



hi soongsc,

these both cards are of year 1999-2001.supportig sampling rates of 48000.so shoud i go wth yamaha and start measuring the drivers.is everything ok now.and what is the cause of this probem .did you ever faced such problem.do i need to add an amplifier or use the sc amplifier.

thanks all you guys for all your support.

thanks

ravs
Click to expand...
I think you could probably use either way. Just be careful and not let your amplifier damage the sc inputs. Normal amplifiers have a voltage gain of about 20 or more. Most sc inputs take about 3v p-p (check your sc specs)

I have ran into more problems than most could imagine.:smash: Just had to solve them one by one. But go ahead and see what your driver measurements look like with the right delay setting.
 
soongsc

soongsc

Member
Joined 2005
Well, it will work now. The clock jitter is still evident, but I don;t think it will create too much of a problem.

There is a problem with the way you are adding weight for T/S extraction. Weight should be as close to the vc circle and balanced on that circle as best you can eyeball the portion of the weight. Not sure how your weight is added to the driver.
 
R

ravslanka

Member
Joined 2006
google.com
soongsc said:
Well, it will work now. The clock jitter is still evident, but I don;t think it will create too much of a problem.

There is a problem with the way you are adding weight for T/S extraction. Weight should be as close to the vc circle and balanced on that circle as best you can eyeball the portion of the weight. Not sure how your weight is added to the driver.
Click to expand...


hi soongsc,

iam using a 5rs coin sticking in the middle of the cap with the help of
hard foam based dual sided adhesive tape.

http://i43.tinypic.com/avnbdv.jpg
http://i44.tinypic.com/2qb6bs7.jpg

tweaking with my soundcard .i changed line in line out controller
sigmatel stac9721t with a via based controller.here are the outcomes.please check these screenshots

http://i43.tinypic.com/2eq5gcp.jpg
http://i43.tinypic.com/14348df.jpg
http://i42.tinypic.com/2r6p9ur.jpg
http://i42.tinypic.com/fz4riu.jpg
http://i41.tinypic.com/68hcic.jpg

i think there is still something wrong when adding mass
both measrements are taken vertically.also when you increase the mass on the cone vas changes .so how could we determine the accuracy for vas and what mass should be used.

thanks in advance

ravs


be a vegeterian.man, most destructive creature of the world.
 
L

lhwidget

Member
Joined 2008
ravslanka said:



hi soongsc,

iam using a rs coin sticking in the middle of the cap with the help of
hard foam based dual sided adhesive tape.

http://i43.tinypic.com/avnbdv.jpg
http://i44.tinypic.com/2qb6bs7.jpg

tweaking with my sound card .i changed line in line out controller
sigma tel stac9721t with a via based controller.here are the outcomes.please check these screenshots

http://i43.tinypic.com/2eq5gcp.jpg
http://i43.tinypic.com/14348df.jpg
http://i42.tinypic.com/2r6p9ur.jpg
http://i42.tinypic.com/fz4riu.jpg
http://i41.tinypic.com/68hcic.jpg

i think there is still something wrong when adding mass
both measrements are taken vertically.also when you increase the mass on the cone vas changes .so how could we determine the accuracy for vas and what mass should be used.

thanks in advance

ravs


be a vegeterian.man, most destructive creature of the world.
Click to expand...


Ravs,
The best advice I can offer when using added mass to find Vas;
1) Orient the driver with its axis horizontal (frame vertical)
2) Weigh the mass to the nearest 0.01 gram
3) Support the driver firmly so the frame can't move in reaction to the cone's movement
4) Make sure the mass can't move relative to the cone.
5) Try a test signal level of 1 V(rms) (The higher the the test signal level, the lower f(s) & larger V(as)).


The curves look much better, the only thing I see is the second resonance at about 450 Hz. You might try a sine wave sweep from 200 Hz to 600 Hz. I think you will hear a buzz (or some other anomaly) at about 450 Hz.

A driver the size you are testing isn't real sensitive to being tested with its axis vertical, & unless the double sided tape is acting like a pad between the cone and coin you are probably ok with coupling the added mass securely to the driver's cone.

What voltage was your test signal when you tested the driver?
 
R

ravslanka

Member
Joined 2006
google.com
hi lhwidget,

when measuring the driver i didnt see the cone moving at those signal level.i didnt measure the voltage.should i produce a sine wave of 1khz and measure the voltage on the driver or without driver connected and adjust the outputof the amplifier to obtain 1vrms.and decreasing the sound level in soundeasy.please explain.


" You might try a sine wave sweep from 200 Hz to 600 Hz. I think you will hear a buzz (or some other anomaly) at about 450 Hz"

areyou referring to analog measurements .

thanks

ravs



be a vegeterian.man, most destructive creature of the world.
 
L

lhwidget

Member
Joined 2008
While the MLS signal is running, measure at the amp's speaker terminals, go for about 1 V(rms). It should be the same open circuit or with the driver connected.

I meant that I would do a sine sweep using the analog measurements function just to listen for a buzz, rattle, or other noise indicating a problem.

Sometimes bumps in the impedance curve when using MLS test signals are caused by resonances resulting from problems.
 
soongsc

soongsc

Member
Joined 2005
ravslanka said:



hi soongsc,

iam using a 5rs coin sticking in the middle of the cap with the help of
hard foam based dual sided adhesive tape.

http://i43.tinypic.com/avnbdv.jpg
http://i44.tinypic.com/2qb6bs7.jpg

tweaking with my soundcard .i changed line in line out controller
sigmatel stac9721t with a via based controller.here are the outcomes.please check these screenshots

http://i43.tinypic.com/2eq5gcp.jpg
http://i43.tinypic.com/14348df.jpg
http://i42.tinypic.com/2r6p9ur.jpg
http://i42.tinypic.com/fz4riu.jpg
http://i41.tinypic.com/68hcic.jpg

i think there is still something wrong when adding mass
both measrements are taken vertically.also when you increase the mass on the cone vas changes .so how could we determine the accuracy for vas and what mass should be used.

thanks in advance

ravs


be a vegeterian.man, most destructive creature of the world.
Click to expand...
I've been on business trip to tend the bicycle show for the last few days. But looking at the pictures, I would say the best way to add weight for this case is to distribute the weight along the intersection of the dust cap and cone.
 
R

ravslanka

Member
Joined 2006
google.com
soongsc said:

I've been on business trip to tend the bicycle show for the last few days. But looking at the pictures, I would say the best way to add weight for this case is to distribute the weight along the intersection of the dust cap and cone.
Click to expand...

hi soongsc.

i found it the easiest way .i have to fing an alternative.coins are of fixed weight .no need to measure them again and again as in blue tac or putty.


hi lhwidget,

thanks i will be back with 1v test results .

thanks

ravs



be a vegeterian.man, most destructive creature of the world.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Top Bottom