ARTA - Laser
Hi Tamas,
I think there is no problem. Have a look on the definitions in the manual.
I dont know this method you call "known SPL method". There are some other methods introduced by Mark Ureda and Withold Waldman based on curve fitting.
Do you mean this methods or am I totally wrong?
Yes you can use the laser as any other sensor but not at the same time (at the moment). You should get it for the price of a good microphone (500-600 €).
Regards
Heinrich
Hi Tamas,
I think there is no problem. Have a look on the definitions in the manual.
I dont know this method you call "known SPL method". There are some other methods introduced by Mark Ureda and Withold Waldman based on curve fitting.
Do you mean this methods or am I totally wrong?
Yes you can use the laser as any other sensor but not at the same time (at the moment). You should get it for the price of a good microphone (500-600 €).
Regards
Heinrich
Hi Heinrich,
What do you mean with no problem and definitions???
I was thinking on the "Known SPL" method used by the cheapo TSP measurement hard- and software WT-3 sold by Part Express (Dayton)
German site:
www.intertechnik.de
I also find the dual gated response quite good, but a more useable soultion would be for quick live measurements the method used by SMAART (fppo) or SAT (smoothFFT) or Praxis(FLEX window)
As you see each has its own fantasy name, but they are the same.
They are using 9-12 different time window sizes for different frequency bands and do the FFT for each and display the end result in one graph.
With this method you get quite good smooth response curves at HF and still get detailed LF data...
Tamas
What do you mean with no problem and definitions???
I was thinking on the "Known SPL" method used by the cheapo TSP measurement hard- and software WT-3 sold by Part Express (Dayton)
German site:
www.intertechnik.de
I also find the dual gated response quite good, but a more useable soultion would be for quick live measurements the method used by SMAART (fppo) or SAT (smoothFFT) or Praxis(FLEX window)
As you see each has its own fantasy name, but they are the same.
They are using 9-12 different time window sizes for different frequency bands and do the FFT for each and display the end result in one graph.
With this method you get quite good smooth response curves at HF and still get detailed LF data...
Tamas
You can use a combination of resistors if you want exact values.
However I think you can use different value resistors and adjust the values in your set up ( computer input when calibrating ).
I am about to make an input box myself but have not yet read the set up details closely. Read up your instructions again. Maybe the values you have are fine.
However I think you can use different value resistors and adjust the values in your set up ( computer input when calibrating ).
I am about to make an input box myself but have not yet read the set up details closely. Read up your instructions again. Maybe the values you have are fine.
I’ve redrawn the diagram . I’m looking through the application note.
I think that R1 must be = R3 and R2 = R4.
A formula is given to calculate the variable ‘r’ with different resistor values.
The 27 ohm resistor is not mentioned. Maybe I have to go back to the ARTA user’s manual.
Note that both channels must see the same source resistance.
The L channel measuring the mic output will see R5 ( = 715 ohms ) + Z out of preamp assumed to be 100 ohms. This is totally = 815 ohms.
the other voltage dividers will each be 910 ohms parallel 8.2K .
This is about 819 ohms. That is within 0.5 % of the mic measurement setting.
So if you change any resistors you will have to make sure this relationship is maintained.
I think that R1 must be = R3 and R2 = R4.
A formula is given to calculate the variable ‘r’ with different resistor values.
The 27 ohm resistor is not mentioned. Maybe I have to go back to the ARTA user’s manual.
Note that both channels must see the same source resistance.
The L channel measuring the mic output will see R5 ( = 715 ohms ) + Z out of preamp assumed to be 100 ohms. This is totally = 815 ohms.
the other voltage dividers will each be 910 ohms parallel 8.2K .
This is about 819 ohms. That is within 0.5 % of the mic measurement setting.
So if you change any resistors you will have to make sure this relationship is maintained.
Attachments
Transit USB measurements
For those using the M-Audio Transit USB I measured the following parameters today.
Z in = 12 K ohms
Z out = 68 ohms
Measured using 100 Hz sine. Maybe there is a decoupling cap at the input / out that might require a higher frequency for accurate results ?
Can anyone verify this ? I'll repeat this at 1Khz later. No time now.
For those using the M-Audio Transit USB I measured the following parameters today.
Z in = 12 K ohms
Z out = 68 ohms
Measured using 100 Hz sine. Maybe there is a decoupling cap at the input / out that might require a higher frequency for accurate results ?
Can anyone verify this ? I'll repeat this at 1Khz later. No time now.
I opened my Transit USB !
R out is a 47 ohm resistor and Cout is 10uF .
I couldn't figure out how the input circuitry is . It measures just under 11k ohms with a DMM at the input terminals and seems to have a 10uF at the input. So around 5 k ohm is about correct I guess ( assuming R-C-R ).
This makes my external box design a bit more involved.
TOOLMOX looks nice. Yes , surely not for a beginner.
R out is a 47 ohm resistor and Cout is 10uF .
I couldn't figure out how the input circuitry is . It measures just under 11k ohms with a DMM at the input terminals and seems to have a 10uF at the input. So around 5 k ohm is about correct I guess ( assuming R-C-R ).
This makes my external box design a bit more involved.
TOOLMOX looks nice. Yes , surely not for a beginner.
ARTA MessBox
It seems that measurement equipment is an ongoing topic.
If you are interested in a PCB solution of the ARTA MessBox here you will find all the necessary informations (layout etc.):
http://www.mini-cooper-clubman.de/html/messung.html
Please feel free to use it however you want.
Regards
Heinrich
It seems that measurement equipment is an ongoing topic.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
If you are interested in a PCB solution of the ARTA MessBox here you will find all the necessary informations (layout etc.):
http://www.mini-cooper-clubman.de/html/messung.html
Please feel free to use it however you want.
Regards
Heinrich
ARTA PCB MessBox
... now with a link to an english page
http://www.mini-cooper-clubman.de/html/hifi_measurement.html
Regards
Heinrich
... now with a link to an english page
http://www.mini-cooper-clubman.de/html/hifi_measurement.html
Regards
Heinrich
Might want to post the box info and associated links here....
http://tech.groups.yahoo.com/group/arta_users/
http://tech.groups.yahoo.com/group/arta_users/
ARTA 1.5
Hi folks,
ARTA 1.5 is coming in a few days.
What's new:
ARTA 1.5
- recording of impulse response (PIR) with external pulse (trigger for shot capturing)
- automatic ISO 3382 parameter estimation
- ISO 3382 parameter estimation in 1/1 and 1/3 octave bands with graphical and table presentation
- estimation of acoustical spatial parameters (IACC, LF and LFC)
- delay for phase adjustment in FR2 window.
- 1/1 octave SPL RTA noise rating (NR,NC, PNC, RC, NCB)
- 1/3 octave SPL, specific loudness, loudness in Sone and loudness level in Phon
- saving/loading all overlays in FR2 window
- export of wav in floating point format also
Eliminated bugs:
- overlay refreshed after recording in PIR window
- directivity pattern from gated response
STEPS 1.5
- Integration of overlays
Have a look on ARTA's homepage during the next days: http://www.fesb.hr/~mateljan/arta/download.htm
Regards
Heinrich
Hi folks,
ARTA 1.5 is coming in a few days.
What's new:
ARTA 1.5
- recording of impulse response (PIR) with external pulse (trigger for shot capturing)
- automatic ISO 3382 parameter estimation
- ISO 3382 parameter estimation in 1/1 and 1/3 octave bands with graphical and table presentation
- estimation of acoustical spatial parameters (IACC, LF and LFC)
- delay for phase adjustment in FR2 window.
- 1/1 octave SPL RTA noise rating (NR,NC, PNC, RC, NCB)
- 1/3 octave SPL, specific loudness, loudness in Sone and loudness level in Phon
- saving/loading all overlays in FR2 window
- export of wav in floating point format also
Eliminated bugs:
- overlay refreshed after recording in PIR window
- directivity pattern from gated response
STEPS 1.5
- Integration of overlays
Have a look on ARTA's homepage during the next days: http://www.fesb.hr/~mateljan/arta/download.htm
Regards
Heinrich
Hi Heinrich,
Thanks for the heads-up on ver. 1.5. I’ve been using Arta software for a few months now and I’m seriously thinking of purchasing a license, because it really is a delight to have such a great software interface to make acoustic and electrical measurements. I’m using the M-Audio Audiophile 192 sound card, which has great specs and compliments the fine performance and features of Arta.
Having said this, I would really like to ask you a question regarding the measurement of cone displacement.
I note that there is an application note on this subject that describes the use of a laser-based instrument that interfaces with the Arta software. I also note that other manufacturers of similar software use this type of instrument to make these measurements. But this type of instrument is a little too expensive for the likes of me and I wondered if you felt it possible to derive the displacement curve from say the near-field SPL response of a driver. I thought of this idea some years ago when I had the good fortune of having access to LinearX’s LEAP 5 simulation software, which shows the cone acceleration curve looking exactly the same as the SPL curve when both are displayed on a logarithmic vertical scale. So it seems intuitive to me that SPL and cone acceleration are linked by some physical constants. As a result of this observation, it has always stuck in my mind that cone displacement can very simply be derived from the acceleration curve if it’s divided by omega squared (2PiF)^2.
Do you think this could be done simply with the use of a calibrated microphone and a data entry field in Arta to enter a few pertinent parameters or am I way off base with this idea ?
Best regards
Peter
Thanks for the heads-up on ver. 1.5. I’ve been using Arta software for a few months now and I’m seriously thinking of purchasing a license, because it really is a delight to have such a great software interface to make acoustic and electrical measurements. I’m using the M-Audio Audiophile 192 sound card, which has great specs and compliments the fine performance and features of Arta.
Having said this, I would really like to ask you a question regarding the measurement of cone displacement.
I note that there is an application note on this subject that describes the use of a laser-based instrument that interfaces with the Arta software. I also note that other manufacturers of similar software use this type of instrument to make these measurements. But this type of instrument is a little too expensive for the likes of me and I wondered if you felt it possible to derive the displacement curve from say the near-field SPL response of a driver. I thought of this idea some years ago when I had the good fortune of having access to LinearX’s LEAP 5 simulation software, which shows the cone acceleration curve looking exactly the same as the SPL curve when both are displayed on a logarithmic vertical scale. So it seems intuitive to me that SPL and cone acceleration are linked by some physical constants. As a result of this observation, it has always stuck in my mind that cone displacement can very simply be derived from the acceleration curve if it’s divided by omega squared (2PiF)^2.
Do you think this could be done simply with the use of a calibrated microphone and a data entry field in Arta to enter a few pertinent parameters or am I way off base with this idea ?
Best regards
Peter
Measuring Displacement with STEPS
Hi Peter,
you are on the right track. If no laser is available one can use:
- simulation software for the calculation of displacement (e.g. AJ Horn: http://www.aj-systems.de/indexe.htm). Combine measured data (via CSV-Export) and displacement in XLS
- connect the second LineIn to LineOut and use sensitivity [mV/mm] calculated by simulation software (e.g. AJ Horn)
For some more details have a look on the Visaton webpage: http://www.visaton.de/vb/showthread.php?t=14154&highlight=klippel+light
It's in german language but with a lot of pics
Regards
Heinrich
Hi Peter,
you are on the right track. If no laser is available one can use:
- simulation software for the calculation of displacement (e.g. AJ Horn: http://www.aj-systems.de/indexe.htm). Combine measured data (via CSV-Export) and displacement in XLS
- connect the second LineIn to LineOut and use sensitivity [mV/mm] calculated by simulation software (e.g. AJ Horn)
For some more details have a look on the Visaton webpage: http://www.visaton.de/vb/showthread.php?t=14154&highlight=klippel+light
It's in german language but with a lot of pics
Regards
Heinrich
ARTA MessBox
... pcb's for ARTA MessBox are available again
http://www.mini-cooper-clubman.de/html/hifi_measurement.html
Regards
Heinrich
... pcb's for ARTA MessBox are available again
http://www.mini-cooper-clubman.de/html/hifi_measurement.html
Regards
Heinrich
im a bit cofused... TSP measurement LIMP
Hi all,
I have done some TSP measurements recently wit some speakers, and I've got VERY different TSP date with the added mass and the closed box methode....
Anybody can explain this?
I try to attach a compressed folder with one measurement...
Thanks,
Tamas
Hi all,
I have done some TSP measurements recently wit some speakers, and I've got VERY different TSP date with the added mass and the closed box methode....
Anybody can explain this?
I try to attach a compressed folder with one measurement...
Thanks,
Tamas