Does external clocking make an audible difference?

[The Marrvel]

Due to the limitations of the digital input of my macbook, I'm unable to use my API A2D as the master clock. I'm still able to record using the A/D of the API but the macbook is clocking everything.

If I were to purchase an interface that would allow me to use the A2D as the master, would I even notice an audible difference between that and the macbook internal clock?

[Drumrecording]

Yes! I use a Big Ben. This Big Ben clock the ProTools HD3 Accel System. When I switch to the internal ProTools Clock I hear a muffled sound.

Try it!

[glissando]

yes in general, but I'm not familar with the API clock. I assume it's a decent build.

[theblue1]

Clarification needed: are you running the A2D's analog outs into the MB?

Because if you're sending from the A2D's digital outs into the MB, the MB is presumably deriving embedded wordclock from the A2D.

With regard to whether you'll hear a difference, it's entirely possible -- under certain circumstances.

The most likely result, the experts[1, 2] us, of slaving a given converter to an external source is increased jitter in the slaved converter. However, since you're not apparently using the MB's converter at that point, the increased jitter in the MB converter would presumably not be an issue during tracking. (At least if I've had enough coffee this morning. ) Keep in mind, that if you're using multiple converters in tandem that you must have one master and slave other converters to that master source (which could either be one of the converters or a dedicated clock source like the Big Ben, Timepiece, etc).

Here's Dan Lavry on the notion of slaving to an external clock in order to 'improve' the sound: Will clocking MOTU 828 mkI to Mytek Stereo192 improve DA of 828?

[Alex Specht]

Originally Posted by The Marrvel

A/D of the API but the macbook is clocking everything.

Seems that you are not actually clocking the API off the Macbook, rather the Macbook it automatically adjusting to what its being fed (via SPDIF with optical adapter i assume).

An interface with WC, AES would theoretically make for a more stable clock sync between devices.

Or you could try to send the output of the Macbook into the spdif input of the API and see if it will actually sync to the Mackbook.

Are you seeing the "external sync" light of the API coming on?

[The Marrvel]

Originally Posted by theblue1

Clarification needed: are you running the A2D's analog outs into the MB?

No, I'm using digital. The A2D spdif output is being converted through an M-Audio CO2 coax/optical converter into the optical input of the Macbook. The folks at API already told me that the Macbook's built-in soundcard won't be able to set the A2D as the clock source and that another interface will have to be used. I just don't want to spend money on a brand new interface if using the API as the clock source won't really improve the sound.

After viewing the links that you sent me, I gather that perhaps it won't improve?

[heyman]

Marvel, the nice thing about your setup is that it is portable. Take your rig into a dealer and try out that big ben.. See if it makes a diffrence. That way you havent spent dime one to test it out.

[John Eppstein]

Originally Posted by heyman

Marvel, the nice thing about your setup is that it is portable. Take your rig into a dealer and try out that big ben.. See if it makes a diffrence. That way you havent spent dime one to test it out.

You're missing the point of the question - he already has a clock source, which he can't use. He needs a new INTERFACE, not a new clock - with the current setup he couldn't use the Big Ben anyway.

To the OP - yes, you need to buy a REAL interface instead of the onboard generic crap.

[Butcha]

Any firewire interface that can be clocked off the A2D should work. I am not completely clued in regarding what is available, but you should be able to pick up an mbox or mbox equivalent fairly cheaply.

[Slikjmuzik]

Originally Posted by John Eppstein

You're missing the point of the question - he already has a clock source, which he can't use. He needs a new INTERFACE, not a new clock - with the current setup he couldn't use the Big Ben anyway.

To the OP - yes, you need to buy a REAL interface instead of the onboard generic crap.

Eppstein's right, minimally you need an interface with a Spdif input which takes in the digital information as well as spits out a clock source at the same time which the interface should offer the option to clock to the Spdif input. Even more ideal is if the interface had a Wordclock input and output (BNC).