Asus Essence STX Extension Oustide The Case?

[5th element]

Originally Posted by Raj1

Because any modulation is imposed on the output. Of course if you're only playing with sine waves, carry on as you are and have fun.

Supply modulation? This is simply an extension of inductive distortion as described by Self and is visible with sine waves. People seem to like throwing the old 'we listen to music, not sine waves' as some kind of way of proving something wrong, but this has little to do with it. Music is, at the end of the day, simply lots of sine waves added together. One can simplify things for the measurement process and analyse the system using only one frequency at a time, or they can go to the extent of measuring with multi-tone stimuli, but the end results will end up being the same.

The point is that if the supplies and the surrounding decoupling and layout were insufficient then you would see this in the measurements.

Some of us like overkill without 5 inches of wire, especially for analogue.

Good luck modding the Xonar then.

[Raj1]

Originally Posted by 5th element

Supply modulation? This is simply an extension of inductive distortion as described by Self and is visible with sine waves. People seem to like throwing the old 'we listen to music, not sine waves' as some kind of way of proving something wrong, but this has little to do with it. Music is, at the end of the day, simply lots of sine waves added together. One can simplify things for the measurement process and analyse the system using only one frequency at a time, or they can go to the extent of measuring with multi-tone stimuli, but the end results will end up being the same.



Good luck modding the Xonar then.

When you've performed those measurements in 1Hz increments between 20Hz and 15KHz, and then with multiple sine waves at the same time drop me a line.

[marce]

Qusp, it was just to show the one of the new packaging styles for mosfets, IR have some very interesting packages as well, it was nothing to do with the electrical specifications. Over the last decade component packaging has evolved, pushed by the requirements for more in less space, and the requirement to get the heat away from the actual chip. The new packaging is designed to reduce the junction to case thermal resistance allowing for more efficient removal of heat from the die. One of my favorite MosFet packages is this:
http://www.irf.com/technical-info/appnotes/an-1035.pdf
With the right design with a metal case you can arrange the layout so that the case becomes the heatsink, much easier for automated production than TO-220s.
With a digital to analogue system and the right equipement you can feed a controlled set of step frequencies and automaticly monitor the waveform, and also a controlled mix of frequencies, often done when CS101 tests have to be carried out.

[SoNic_real_one]

Originally Posted by Raj1

When you've performed those measurements in 1Hz increments between 20Hz and 15KHz, and then with multiple sine waves at the same time drop me a line.

Fourier says that we don't need to... But maybe you know more math than the rest of the world.

[5th element]

Originally Posted by Raj1

When you've performed those measurements in 1Hz increments between 20Hz and 15KHz, and then with multiple sine waves at the same time drop me a line.

I don't think you understand what's going on here. Electronic devices aren't like loudspeakers, they don't show peculiar resonances at unusual frequencies. One does not need to perform sine wave distortion measurements at every conceivable frequency to prove that a design or device has no intrinsic problems. Sure, you need to perform enough measurements to be able to reveal certain trends, like rising distortion with rising frequency, due to the diminishing effect of feedback, but beyond that it's largely pointless to increase the step sizes. The same goes for doing it with multiple sine waves.

Now electronic devices do show resonance issues with high speed circuits, but this occurs at very high frequencies, much higher then you're ever going to encounter within audio work. Of course you could purposefully design in resonances within the audio band using certain filters, but why would you want to do that? And on top of that you'd be aware of it as you put it there in the first place.

[Raj1]

Originally Posted by SoNic_real_one

Fourier says that we don't need to... But maybe you know more math than the rest of the world.

Nope, it's just that I think the dynamics of complex passages are not easily represented by the kind of measurements we tend to rely on. But hey, that's an argument that cannot be reasoned out as far as I am concerned.

[phofman]

Originally Posted by Raj1

Nope, it's just that I think the dynamics of complex passages are not easily represented by the kind of measurements we tend to rely on. But hey, that's an argument that cannot be reasoned out as far as I am concerned.

If the complex passages are band-limited to fs/2, then fourier holds no matter how complex they are.

[wushuliu]

I'm sure this thread will spiral into tangential inanity regardless, but the important mod to be done on the ST/X cards is replacing the clock - Vanguards are available on ebay. It is a substantial increase in sound quality. This has been covered elsewhere on the web with a lot of positive feedback.

From what I have read elsewhere, power supply mods are not as beneficial.

[marce]

Any real proof! or just listening?

[wushuliu]

Listening. It's very evident. Nothing subtle about it.