AD/DA Converters

[JLM]

This is probably a newbie question but I am unsure when it comes to this area of digital recording. I know that ultimately everything from the mic source to the converter you use will affect sound quality. How do D/A and A/D converters work into the overall picture?

Right now I own a MOTU 24i which is just their standard 24 input A/D converter hardware. Am I correct in that each input on the MOTU contains one A/D converter? If this is true then I would assume that the converters on the MOTU are pretty cheap since I know that it runs close to $2000 to buy a unit that contains only 2 A/D converters from Apogee.

I'm also confused in how I would hook such a unit up to my existing setup. Would the Apogee take the place of my MOTU or would I keep the MOTU and just place the Apogee (or any other nice A/D converter) into the signal chain? I'm confused. Obviously this is really a pro area that I won't be in for awhile but I'd still like to learn more about this topic. Thanks.

 

[Middleman]

How do D/A and A/D converters work into the overall picture?

There are poor convertors and great convertors which can affect the final result. To make it more confusing great convertors sometimes are surrounded by poorly designed supporting circuits which degrade the performance and thus sound. Then there are great convertors and great designs. These generally start around $1000.

Midrange and lo end conversion have artifacts and over or under frequency emphasis. These can throw off your mixing results but you can learn these characteristics over time and compensate. They become a pain however and drive most to buy better gear.

Am I correct in that each input on the MOTU contains one A/D converter?

Yes

If this is true then I would assume that the converters on the MOTU are pretty cheap ...

Yes

Would the Apogee take the place of my MOTU ...?

If you can afford them you will hear the difference and not want the Motu.

Obviously this is really a pro area that I won't be in for awhile but I'd still like to learn more about this topic.
Gearslutz.com debates high end convertors all day long every day. There is a wealth of information there.

 

[Bowisc]

I find that the actual conversion in these boxes isn't so much the problem, but rather, the analog I/O. This is where most consumer boxes fail. Also, some interfaces may sound great at one sampling rate and not another. An example is the MOTU HD192: sounds sweeeet at 44.1, but it sucks at anything above that, IMHO. Okay, maybe 96K is "okay" but it shines at 44.1 in my opinion.

I've been using a Motu 828mkII for over a year now. I upgraded my DA to a Benchmark DAC1 three months or so later... and heard a lot of improvements on that end. So now, I've upgraded the AD to an Apogee Rosetta 800.

I marvel at what I've been missing, sonically.

Not that the 828 was/is horrible for the average consumer, which is the market they are going after. But as your hearing develops, you will want equipment that will work better for you, and not against you. If you're hearing isn't developed, it wouldn't matter much what gear sits in front of you, to a certain degree of course.

 

[JLM]

Hey, thanks for the great responses Middleman and Bowisc. That definitely answered some of my questions there Middleman. I'll check out Gearslutz to learn more.

 

[OneArmedScissor]

I've been using a Motu 828mkII for over a year now. I upgraded my DA to a Benchmark DAC1 three months or so later... and heard a lot of improvements on that end. So now, I've upgraded the AD to an Apogee Rosetta 800.

That's cool. I was wondering about the Rosetta 800. It looks like a really good deal for the money. Apogee also has the AD-16X and DA-16X, which I would imagine are as good as it gets or close to it, but that would cost like twice as much, just for similar units. That looks to me like the point of diminishing returns for your money, so the Rosetta 800 seems like the happy medium.

So can you just use the X-FireWire card to use it as a stand-alone interface with a computer? That's the way I understand it, but I just wanted to check.

 

[Bowisc]

That's cool. I was wondering about the Rosetta 800. It looks like a really good deal for the money. Apogee also has the AD-16X and DA-16X, which I would imagine are as good as it gets or close to it, but that would cost like twice as much, just for similar units. That looks to me like the point of diminishing returns for your money, so the Rosetta 800 seems like the happy medium.

So can you just use the X-FireWire card to use it as a stand-alone interface with a computer? That's the way I understand it, but I just wanted to check.

Yes, you can use it as a stand-aline FW interface. Neat huh? I hear that the routing software will be very useable as well.

Once the cards are out, I plan on getting another Rosetta 800, so I can have 16 channels of pristine I/O.