macbook optical out to spdif....

well.. just buy some optical cables.. then plug the outs and ins into each other from the macbook to the spdif device you want to send/receive audio to/from. that's pretty much all there is to it.
you may have to switch your audio in/out to digital in the sound control panel if you want to hear the system sound out of the digital btw.

as an example, i've connected to a presonus central station this way, and it just works as advertised. the difference in sound when you compare to the analog output of a mac is quite startling.

First, let me say that I'm new to Mac, and I don't quite "get it" yet, but I've really struggled with this Optical I/O.

This is too bad, since the only reason that I bought it was to record music. Here is what I've learned.

You have to configure the Audio devices from a control panel that is in the Utilities folder within the Applications folder on the Hard Drive.

Within this Control Panel you can configure the use of this device, along with the Microphone input and the Built in Speaker Outputs. This Panel lets you select something called an Aggregate Device, which as best I can surmise is an integrated view of I/O for this port, but I can't quite master its use.

After a few weeks I was able to get the input working. I take a Digitial COAX S/PDIF signal out of a Behringer Digital mixing board using a Digital COAX cable (has RCA type plugs) that I bought a a local Best Buy.

You have to convert S/PDIF into optical by a conversion box. When I bought the Mac, they told me that I could find these converters at any Radio Shack. This has NOT proven to be true. I tried local Radio Shacks, Best Buys, Comp USAs, etc. and I even had some of them tell me that no such device existed.

Fortunately, there are many web sites where you can find this, and I used a place Called RAM Electronics from New Jersey. I bought a converter and a cable that had the standard square TOSLINK cable out put. I bought a cable that had the square connecter on one end and the mini TOSLINK connecter on the other. The Mini connector is what you need to input into your Mac.

After another week or two of figuring out how to get Logic Express to recognize the input, I was able to play guitar and record into the MBP by this path. I'd rate that figuring all this out was about on par with learning how to use a new expansion card and application on and Windows machine. However, IT WAS ABSOLUTELY NOT ANY EASIER, and this was a big disappointment for me. I was looking forward to the mythical easy of use of the Mac, and did not find it.

Regarding the use of this port for output, I have not been able to figure that out yet. I discovered too late that the adapter I bought from RAM was a uni-directional converter, which didn't convert back from the optical signal to the S/PDIF digital. I went back to the web site and got a device which is bi-directional, and it just showed up this week. I've tried it, but I am not getting a signal out of the Mac, at all.

I guess I have another week ahead of me to try and figure this out.

The sound, when listened to via headphones is clean. The plug ins and effects work well. I just need to figure out how to drive the output, and then I'll be a happy camper. If anyone can help with that, I'd be much obliged.

Hope that helps.

if somebody tell me it work,i would love to know
where and what i bought(adapter,optical converter
etc) to make it work,
thx

The Fostex COP-1 (about 85USD from Sam Ash) has long been the most cost effective black box around for bidirectional conversion of optical/coaxial. Supports 24 bit and high sample rates, and even AC3 streams. You'll still need to purchase the appropriate cables though.

Once hooked up bidirectionally, set the properties for built-in audio in Audio-MIDI Setup for "digital" in and out, and clock externally. Be careful as some older cheap DAT machines only transmit clock when actually playing and not while idling. Also, avoid using built-in audio in an aggregated device with anything else. It can be problematic.

I have gotten the optical in AND out working on my MacBook Pro C2D laptop.

What you said above about the need to create an "aggregate device" in the Audio MIDI utility above is true. I also found the process counter-intutive, but followed the instructions from a previous post on the forum that was great!

I think the salespeople were speaking of the 1/8"in jack adapters for the TOSLINK cables. I got my cables and adapters at the Apple Store here is San Francisco.

I was connecting optically using the RME FireFace 800 using the TOS connectors on the back of the RME. I also found it a little confusing to get everything working. For me, getting the input from the mic/RME into Logic took some time, but I got it worked out. It is definitely possible to go optical in and optical out.

I did not hear any difference between the optical or firewire in terms of sound quality or latency. They both sound great with unnoticable latency to me. I do have the I/O set at 64 samples and it works great on this machine. I never have more than one mono mic input at a time. I avoid latency causing plug-ins during recording.

I actually went switched back to putting the RME FF800 on a FIreWire800 bus once my Nitro PC ExpressCard firewire 800 card came off backorder. Seemed much more robust than the very delicate optical connections. I had already broken and replaced one optical cable in just two weeks of work. There are several posts on the board about how fragile the 1/8" optical connector is.

I would be curious if anyone thinks the optical is superior in some way over fire wire, or if once the signal is digital it really makes no difference.

I can say my brand new set up if FABULOUS. Fast, rock-solid stable and sounds amazing.

John Dee


MacBook Pro Core 2 Duo 2.33 - 2 GB RAM - 160 GB HD - 30" Cinema Display Mac OS X (10.4.8) Logic Pro 7.2.3 - RME FireFace 800 - LaCie "Rugged" 100 GB 7200 RPM FW Drive

John

If you could send me a pointer/link to the post that helped you figure this out, I'd be much obliged.

When I look at the control panel for the aggregate device, the volume sliders are at zero, and I can't adjust. Something must be overridding te settings, but I don't know what.

I'm glad to know that at least someone figured it out, it gives me hope.

I'd rate that figuring all this out was about on par
with learning how to use a new expansion card and
application on and Windows machine. However, IT WAS
ABSOLUTELY NOT ANY EASIER, and this was a big
disappointment for me. I was looking forward to the
mythical easy of use of the Mac, and did not find
it.

The reason that you have not found this easy is because
you have chosen (unknowingly of course) to do the most
difficult way of getting sound into your Mac. The optical
input sounds like it would be a great way to go. It really is
not since you are using the Macs A/D and D/A converters
which are not as good as, well, as, anybody's.
What you should do is get a dedicated audio interface,
preferably firewire. The RME Fireface 400 sounds like
it would be good for you. They are a company that makes
high quality audio electonics.

Regarding the use of this port for output, I have not
been able to figure that out yet. I discovered too
late that the adapter I bought from RAM was a
uni-directional converter, which didn't convert back
from the optical signal to the S/PDIF digital. I
went back to the web site and got a device which is
bi-directional, and it just showed up this week.
I've tried it, but I am not getting a signal out of
the Mac, at all.

This would not even be an issue if you had a
dedicated interface.

I guess I have another week ahead of me to try and
figure this out.

How much is your time worth. This week could be turned
into a few minutes. The Mac is easier to work with, you just
have to know a few things ahead of time.

The sound, when listened to via headphones is clean.
The plug ins and effects work well. I just need to
figure out how to drive the output, and then I'll be
a happy camper. If anyone can help with that, I'd
be much obliged.

That is what an interface is for, It has preamps for boosting
the incoming signal and at the least has a headphone amp
so you can listen with headphones. You will want to get some
kind of power amp eventually to listen to your output, in the
meantime you can always bounce your material to an AIFF or
MP3 and listen to it in iTunes.

I have gotten the optical in AND out working on my
MacBook Pro C2D laptop.

What you said above about the need to create an
"aggregate device" in the Audio MIDI utility above is
true. I also found the process counter-intutive, but
followed the instructions from a previous post on the
forum that was great!

This feature was designed for when using more than
one external device to make them appear in Logic
as one device, which is what Logic will only work
with. As you found out it can be used with internal audio
as one of the devices but that is not the best way to go.

I would be curious if anyone thinks the optical is
superior in some way over fire wire, or if once the
signal is digital it really makes no difference.

Digital is digital

you are using the Macs A/D and D/A

converters

Sorry, this is incorrect. (stayed up too late)
This signal is already digital. Though
the part about using a dedicated interface
is correct. These I/Os were not originally
intended for this purpose.

Well, I've solved my problem, and this one can't be laid to blame on the Mac, but only on me.

I picked up the instructions for the bi-birectional converter and found out that there is a hard to notice slider switch that allows you to turn off the bi-birectional function. Sure enough, it was turned off on mine. I won't bother to speculate why they added this feature. Nonetheless, when I switched to bi-directional the signal meters on my board came to life and the monitors were filled with sound.

So for now, I'm all set, able to both record and play through the optical device, and I'm looking forward to figuring out how to use Logic Express.

Thanks for responding, each answer gave me something to think about, which is never a bad thing.

Here is the link to the discussion that straightened me out, but I think you already got this far...

http://discussions.apple.com/thread.jspa?messageID=1307777&#1307777

I believe the sound level controls are "supposed" to be grayed out with an optical/digital interface on the Apple. The sound levels need to be controled by the device -- probably propietary to each device.

I have to use the mixer software that came with my RME FireFace to adjust the sound levels. What is the software interface for your device?

John Dee