Would forum members chip in $$ for a USB analyzer

[mansr]

2 minutes ago, plissken said:

To do S.I. Eye measurements we are talking about ~$800 for a scope, probes, and break out board.

That doesn't sound right. Such products cost in excess of $10k. What device are you looking at?

[mansr]

8 minutes ago, plissken said:

You're correct. Just looking for a way to just get clear data.

 

I'm assuming that a protocol analyzer isn't going to do anything for anyone.

A protocol analyser will tell you if there are transmission errors or higher level protocol violations. They are useful mainly when developing hardware. If we trust the host and device to be well-behaved and use reasonable cables, an analyser isn't of much use. Granted, there are many USB devices out there that don't quite follow spec, but DACs from reputable vendors are usually fine. Besides, if the DAC is misbehaving, it won't be fixed by inserting some gizmo in the chain anyhow.

[mansr]

3 hours ago, Miska said:

Ethernet?

Ethernet using what protocol? Unless you're using a dedicated link, you need to deal with address assignment, device discovery, etc before you can even think about sending audio data. But you obviously know all that.

[mansr]

7 minutes ago, Jud said:

Re number 2, was poking around and ran across this: http://www.specs-zurich.com/en/high-resolution-oscilloscope-and-spectrum-analyzer-_content---1--1548--259.html

 

I noticed it features a "1 MS/s sampling rate."  So how, if at all, does it affect measurements we want to do if the measuring device is sampling at a lower rate than some of the clock rates we're dealing with?  Use this tool only for measurements where that isn't a factor, I assume?  (I'm supposing the answer to that may well be "Yes, fool."   )

It also has only 18-bit resolution and 100 kHz analogue bandwidth. This is just barely enough for audio signals. If you want to measure digital signals, look elsewhere. For analogue audio purposes, you might as well use a $500 recording interface such as those from Focusrite, RME, and Tascam.

7 minutes ago, Jud said:

So what sorts of audio system measurements would number 2 and number 3 be useful for?

I don't know what you'd use a vector signal analyser for here. Those are typically used to study complex modulations in RF signals.

[mansr]

48 minutes ago, wgscott said:

Wouldn't it be more cost-effective to find someone who already owns the testing equipment to do the tests in exchange for buying them beer for the remainder of their life or something like that?

So we're looking for an octogenarian with a lab?

[mansr]

3 minutes ago, mansr said:

So we're looking for an octogenarian with a lab?

I suppose a golden retriever is close enough to a lab. How old are you, Bill?