Here an own measurement, done with the RTX6001, from an genuine 24V laptop SMPS followed by a LM317 regulator circuit bringing it down to 21V. So definitely nothing special.
The RTX input was set to 0dBV:
The RTX input was set to 0dBV:
It needs a bit of rework but one can reach the ~ same level of performance that the RTX..
As with many things these days it is also convergence of technologies, namely that modern LDO regs also have much better HF PSRR.
For example, a low noise SMPS feeding LT3045 is a very effective, ultra low noise combination.
T
Hi Terry,
For sure! You won't get top performance without proper technique and component parts.
You can seal the switcher inside a box and bring out your filtered DC using feedthrough capacitors (old technology) and directly into your linear regulators. That ought to get you there.
-Chris
For sure! You won't get top performance without proper technique and component parts.
You can seal the switcher inside a box and bring out your filtered DC using feedthrough capacitors (old technology) and directly into your linear regulators. That ought to get you there.
-Chris
Implementation is always the hard part. Typically some small detail in the grounding and return current paths is overlooked and injects noise across the system. Split supplies can be the worst since that center tap represents multiple source and return currents. In one otherwise well designed system I had to reroute a connection around a transformer the long way or stray fields were coupled into the system. All of this was well below the spec performance floor but made a difference in the phase noise.
Hi Demian,
Stuff like that isn't normally self evident until you spark a new design up. At least it wasn't several problems all contributing to the mess that is the output. Those designs are best simply simpler to begin again from scratch. That would include most power supplies I run across in "high end" audio equipment. A few will be so bad that all you can do is move on to the next piece.
In a nutshell, I agree with you completely!
-Chris
Stuff like that isn't normally self evident until you spark a new design up. At least it wasn't several problems all contributing to the mess that is the output. Those designs are best simply simpler to begin again from scratch. That would include most power supplies I run across in "high end" audio equipment. A few will be so bad that all you can do is move on to the next piece.
In a nutshell, I agree with you completely!
-Chris
What makes you think there is no DC-DC converter inside the 5V power bank. I'm pretty sure there is in most of them. How else would they keep the 5V until depleted etc.
So in that sense it would not be much different from a SM-PSU.
Ok, I "fixed" this. The RTX firmware has changed such that it broke the interface to the MATAA software. Jens helped me out by explaining some of the details of the firmware change. I changed MATAA's interface to the RTX accordingly, and all is well now.
It looks like the AK5394 is going EOL soon 🙁. Have you had a chance to see if AK5572/4/6/8 are as good in terms of distortion?
That's pretty distressing. None of the replacements are really on a par. Many tradeoffs for lower noise and wider bandwidth. The HF noise corner is much lower on all the others as well.
It's to early to forecast production for a last time buy. How long as the AK5394 been available?
-Chris
-Chris
It's a pity with the AK5394A going obsolete. Not easy to find a good replacement, at least for something as critical as an audio analyzer.
