ARTA

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I don't know the right way connecting amplifier output to audio card line input. Is it necessary connecting both input and output return when testing?

Probably. However, you should be careful to note if your power amplifier has a floating "ground" on the output that's not common to the input connection.

The testing setup should be similar to Figure 1.4 of the ARTA manual, but you should probably incorporate a voltage probe as per Figure 1.5. Power amplifiers can hazard the input of your soundcard if not padded correctly.

I suggest to read everything in Section 1.2 of the manual thoroughly.

http://www.artalabs.hr/download/ARTA-user-manual.pdf

Dave.
 
Probably. However, you should be careful to note if your power amplifier has a floating "ground" on the output that's not common to the input connection.

The testing setup should be similar to Figure 1.4 of the ARTA manual, but you should probably incorporate a voltage probe as per Figure 1.5. Power amplifiers can hazard the input of your soundcard if not padded correctly.

I suggest to read everything in Section 1.2 of the manual thoroughly.

http://www.artalabs.hr/download/ARTA-user-manual.pdf

Dave.
Thanks for answer.
I know the reason not connecting the floating "gnd". to GND.
I have see what ARTA manual say about amplifier out interface,but testing some amplifiers in the real world sometimes i have troubles .
 
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Ivo. Thanks for the answer. It is as I had suspected, but was about 40% sure I was wrong. :) Nice to get confirmation and know what to look for.

The 24 bit USB card is the USB-2 from Sound Devices. Expensive and built like a tank. We use their audio and video recorders at work.
 
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Get into the Spa mode and over at the left in the "Gen" field select "Jitter test." (It will scale the J-Test signal frequency based on the Fs that you have selected.)
The signal will then output on your soundcard directly or you can save it to a .wav file using that selection on the Generator drop-down menu.

Dave.
 
Hi,
I'm using STEPS to measure THD, ASIO drivers, and I'm achieving consistent results (loop back shows me residuals similar to the audio card specifications) but one detail is bugging me: Even setting the correct bit depth on ASIO control, the configuration window on steps shows 16bits depht and it's blocked, I can't change that.

Why does it occur? The use of the ASIO driver turns this setting not relevant?

Tks in advance for some enlightenment on this matter.

Regards,
 
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I got into this problem as well. Looks like a little innocent feature.
I can't look it up, still in holidays, but it's something like you should deselect the asio driver, thus the bit depth setting un-freeze, set the desired value, and now select the driver again.
And it might well be dis-regarded anyway, when in asio..
Ciao, george
 
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ASIO bit depth is determined by soundcard Asio control panel, although in some cases control panel has no ability to change the bit-depth. ARTA always check for best possible bit-depth and changes it to float 32 bit format. It is shown in ARTA bit-depth check box, but in STEPS the check box is only grayed. Sorry for thic non-consistency.

Ivo
 
Thank you, Davey and Pano.
 

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Maybe you just have a really clean PCI bus. :)

FWIW, I don't see any 60Hz or harmonics using this new Lenovo laptop with its tiny, hot running PSU. On my ancient Dell laptops with a big brick PSU, there is always a little 60, 120, 180 Hz. But not on battery. Overall noise floor isn't much different, tho.