How do you test an AD Converter?

[bigwillz24]

Cause I just hooked up my Apogee Rosetta up to a MOTU MK2408 MKII and I honestly don't hear a night and day increase in the sound I was expecting reading all the glowing reviews of this thing. Maybe I have something hooked up wrong.

[RezN8]

Originally Posted by bigwillz24

Cause I just hooked up my Apogee Rosetta up to a MOTU MK2408 MKII and I honestly don't hear a night and day increase in the sound I was expecting reading all the glowing reviews of this thing. Maybe I have something hooked up wrong.

Oh yeah, well I just put instant coffee in the microwave and went back in time

So what you're saying is you put the Rosetta THROUGH the MOTU?!? To compare I thought you needed to run them independently of eachother.

[RAK]

Yeah, The MOTU has/is doing A/D/A conversion. How are you hooking things up and what are you trying to do?

If your only analog inputs are from the MOTU then I guess you need to hook up something like this to compare:

1: MOTU as A/D converter, connected directly to computer.
2: MOTU Analog Out -> Analog In Rosetta -> Computer. This is assuming the MOTU has an all analog signal path. And does the Rosetta even have analog Ins?

Once you engage the A/D on the MOTU, you're already digital, and Apogee is just passing the signal. You're going to be limited by your weakest A/D converter.

[Soundmind??]

It sounds like you have them in series...output of the Rosetta into the MOTU. If so, you will not be able to hear and compare them properly. To do that, you will need to run them in parallel, and switch back and forth between them. To really be able to compare them may involve other things like the type of sound being used to compare them, the quality of the other gear involved, and other variables. If your signal path has a weak link (monitors, pre-amp, mixer, etc) it may mask the difference. Try running them in parallel and comparing. If there is no difference you can always buy a 2 thousand dollar pre, a similarly priced set of monitors, a goooood microphone, and record numerous tracks, mix and master them, and you will possibly hear a significant difference. Or you can take advice from others in the business who have used all types of gear and can explain these differences. I've done a little of both. I'm not pretending to have vast knowledge of this stuff. In the past three years I've been doing this I've learned two things. 1- and the most important is that you don't let the salesman at the music supply outlet tell you what you need. Two, even highly experienced recording pros will have different opinions on what is best and what stinks, you just have to read, try things, and try to learn what works, and what doesn't. Depending on the complexity of the sounds you intend to record, the MOTU may be sufficient, or you may need higher end converters...which means more expense.

[mentalattica]

I remember a while back Chess (I think, sorry if I'm giving credit to the wrong person) did a comparison, I'll have to find that thread but I believe he ran audio (x amount of times) through different converters. Sounds like a good way to really compare the 2.

[SonicAlbert]

The MOTU has digital I/O, which should be connected to the digital I/O of the Rosetta. That way you can easily compare the conversion on the MOTU versus the Rosetta.

[chessrock]

Just make sure you're going out of the Rosetta's SPDIF outs to the SPDIF inputs of the MOTU.

But like Mentalattica just mentioned, I posted some sample clips I made comparing the Rosetta with a mid-level audio interface, and the differences were very subtle by all objective accounts. First off, you'd have to have a pretty good monitoring setup to hear the differences. And secondly, you'd have to have a pretty nice recording chain and setup to really even appreciate (or take advantage of) what the converter brings to the table.

[bigwillz24]

I guess i better get started on those API clones I'm building. I hate Backorders.

Heres a bad cell phone pic of my new toys. I replaced the 1212M card with the MOTU. I had my last straw with patchmix.

[Massive Master]

Converters usually wind up as an additive thing - As mentioned, you need some pretty freakin' decent monitoring to hear the effect of a single source -

Just like the distortion and lack of focus from tracking too hot... It's rarely obvious with one track. Stack 24 of them together and that distortion and lack of clarity, veiled imaging, non-responsiveness to subtle EQ and bizarre dynamics anomalies stick out like a sore thumb.

Stepping up your tracking converters is going to give each track that subtle advantage that adds up to recordings that are just "bigger" sounding than with lesser units.