Recent content by phofman

IMHO USB is way more compatible with current and future host devices than firewire. Technically both interfaces are just transferring data anyway, good audio devices have conversion master clocks on their sides. Well engineered (especially multichannel) USB2 highspeed devices use the packet...

Yes, if the ADC distortion component to the combined distortion is negligible, compensating (i.e. adding distortions of opposite phase) on the DAC side only works OK. The problem is when the ADC distortion is not negligible, while being also compensated on the DAC/generator side . Then the...

Separating DAC and ADC distortions from the combined loopback measurement is by principle not trivial. The standard way is using a steep notch filter on the ADC side which suppresses the DAC distortions before the AD conversion. REW supports measuring the notch filter params and compensating its...

@redmountain : how is clock master determined in your "firewire stream"?

@redmountain : what REW buffer size do you use?

But that's not related to some differential mode, but simply averaging the vector distortions of the two channels (each a bit different) improves the resultant distortion, statistically.

It's always perfect cosine to the fundamental sine, IMO just a different phase shift between the channels as that simple equation yields.

IIUC the subtraction can suppress only common-mode artefacts in both channels which is not harmonic distortion.

Maybe it's like this: sin(x) - sin(x-0.001) = 5.×10^-7 sin(x) + 0.001 cos(x) IIUC that 1mV subtracted signal is cos(x), i.e. phase shifted by pi/2. The channels are slightly phase shifted against each other at that frequency - to be expected for real-world HW, they cannot have identical...

Quite a few people use REW on linux with no major issues. Me - Mint Mate, Xorg. Since REW is plain java - do java GUI apps run OK on your installation? Do you have a reasonable set of fonts installed? Perhaps Wayland vs. Xorg?...

IMO much easier (and technically viable) is to precisely fine-tune the gain in the digital domain. It's very unlikely a HW would surpass the precision the digital gain offers. IMO ADCiso has no advantage in precise gain alignment - it has input amplifiers just like any other ADC. 10-turn pots -...

I played with the virtual symmetrical mode not in REW, but directly in linux audio chain https://www.diyaudio.com/community/threads/virtual-balanced-in-out-from-regular-soundcard-in-linux-results.326747/ (the principle is identical). The results were good, but it required calibrating the...

Perhaps your AVR's AUX1 input uses different DSP setting than AUX2?

Perhaps https://forums.steinberg.net/t/windows-11-update-23h2-just-installed-has-crashed-the-asio-driver/971904/11 ?

IME the requirement for a GUI software on a headless server is quite common. E.g. I needed to convert LyX files to PDF automatically on a headless server. I have always used Xvnc (part of TightVNC, debian package tightvncserver) with good results. If access to the GUI is actually needed, any...