@Mr. Scram - XY for channel separation waveform display
@Dave
Here are observations of various scope behavior before I posted my questions:
1. I played with a friend's 14-bit National Instrument PXI-5122 scope and it was dreadfully slow, even though it was supposed to be sampling at 100MS/s.
2. While we know 8-bit and even 10bit scope noise floor is likely inadequate for audio, even the NI 14-bit scope's noise floor was no better than 105dBV. And that's not anywhere near any 24 192 soundcard at -140 to -150dBV.
3. I already have a 24 192 soundcard running ARTA and it worked pretty well for frequency domain work but for time domain, its <400kS/s sampling means very jagged waveforms on DSO, especially when zoomed in a bit.
4. I also already have a Tek 2247a analog scope - it's a hybrid scope - ADCs for measurements and readouts, analog tube for waveform display, but it has no storage, and when zoomed in to see rise time on higher frequencies, the waveform is barely visible.
The quest to find a scope that can do near-analog waveform displays, give better than 0.5% accuracy measurements (the Tek 2247A is like 15% to my eyes) and can zoom in - live or history mode - to see and measure without squinting. The 24 192 soundcard can do all the frequency domain stuff like FFTs, THD and sweeps but they cannot do good waveforms. Therefore my preference is really to see a waveform better than to measure it better.
Budget is under $5k - the DSOX3014T would be a real stretch as it's a lot more than the DSOX3014A and 3.5x that of the DSOX1204G. The RTB seems to give up responsiveness when it's taxed.
Everyone has valid points and this noob is no closer to a decision. So I am asking for votes to see if the numbers tell a clear picture.
Unfortunately the numbers won't tell you. Small details matter, a lot.
Your need for an X-Y mode is fairly unique. For that why not stick with an analog scope?
I would focus on the low noise audio requirement first, for which the Keysight isn't well suited due to it's software magnified front end.
But it's just one of many (often conflicting) requirements.
For starters, what is your budget? and if you are considering the 3000T it's obviously rather high.
When you have a large budget then other things come into play, like maybe more than one scope for different requirements.
e.g. a general cheap-ish 4CH scope for general daily use + a specialised scope for analog audio performance (could even be a high resolution USB scope) might be a better solution and than s single expensive scope that doesn't do all that you want.