Of Macs and Optical.

[garyi]

Guys my deliberations over a new mac continue and I am interested in the optical out facility of the mac, here are the specs:

Data Format: in=S/PDIF out: S/PDIF
Connector Type: Toslink optical
Sample Rates: External Clock 3skHz, 44.1kHz, or 48kHz, internal clock 16kHz to 96 kHz
Bits per sample: 16 or 24
Signal to noise ratio: external clock mode Greater than 130db, internal clock mode less than - 110db
Total Harmonic Distortion: External clock, less than 0.000001 percent, internal clock mode less than 0.0003percent

It uses a sony/phillips digital interface

It also has analog inputs/outputs.

So firstly I hopoe someone can make sense of that lot! What I need to know is the following. If I were to use the mac as a source for software replay would it be OK?

Secondly, would I be able to, or require a DAC to run the music into the back of the hifi?

Thirdly, distance could be an issue, the mac is approximatly 6 metres of wire away. Can either interconnects from a dac out put go that far, or the ooutput from toslink to Dac go that far?

This is all serious questions so anyone that could shed some light!

Also I think long term the music would become harddrive based on a adedicated unit, in uncompressed format. What is important to remember here is that I have more records than CD and 70% of my listening is done on the black stuff, so the digital software replay needs to be great, not seminal!

 

[michaelab]

Yes, you could connect it to your hifi directly as it has analog outputs (might need an adapter if it's a headphone style output socket).

You could also connect it to a DAC with a TosLink (optical) cable. The digital format is S/PDIF (Sony Philips Digital InterFace) which is the standard. Running a TosLink cable over 6m may not be possible. I don't know if they make them that long but even if they did I believe the losses over that length would be too great. You could certainly run analog interconnects from a DAC near your MAC over 6m though.

If you're thinking of a DAC you obviously would need one with a TosLink optical input.

If you used the Mac in conjunction with a decent DAC then the quality would be very good. Using an optical connection to connect the two minimizes the transfer of RF noise from the Mac to the DAC (and the rest of your system).

Michael.

 

[joel]

Gary,
If you wanted to use the TOSLINK, then you would need a DAC somwhere else in the chain.
If you plan to buy a G5, it does have analogue outs. On the G5, this is a single 3.5mm stereo mini jack. What you need is a stereo mini-jack --> L/R RCA cable (I don't know if this would work into Naim, sorry). this should enable you to plug the G5 straight into you preamp (we run the audio outputs of the G5 and G4 here into a Behringer mixer - and it works just fine).
Buying a better PCI soundcard (midiman, terratec etc) should give you better quality - this is what I do at home. Works very well.
HTH

 

[nsherin]

You can also buy adaptors that can convert Co-ax to Optical and Optical to Co-ax for about £15 from Maplins. I use a Co-ax to Optical adaptor between my CDP (which is Co-ax only) and MD (which is Optical only).

 

[garyi]

I currently have analoge output on my G4 to the hifi, its not bad but not great.

My hope is the optical route, assumption beinge that the specs for the analoge side has more distortion rated.

Joel.

I won't be considering a 'better' sound gcard for the mac, the mac sound is generally very good, and there isn't a lolt available for mac as a result of this.

The G5 also has PCIx slots which sould like they arn't gonna have a lot available for them right now!

I'm off into central london for a shufty. (Holiday this week, yippee)

One other thing. When all is said and done, I don't think I am going to be getting the quality available from my Naim CDi, my assumption is that a DAC should not be offering anything to the sound, rather converting the signal with as little loss as possible? If that is the case what should I look for on a DAC, are they available in a small, hid out of the way stylee, and at resonable cost. Let say 200-300 quid tops. ALso would there be specs on the dac I need to match with the Apple (Yes I understand that toslink would be essential)

 

[joel]

Originally posted by garyi

I won't be considering a 'better' sound gcard for the mac, the mac sound is generally very good

This is true. The quality is "good enough" for pro video (what we use it for) out of the box, albeit with the right software.
The m-audio cards do have mac drivers and are very popular with the mac audio community I believe. M-audio also do DACs, and FwIW, some interesting looking firewire DAC solutions that should be within budget.
www.m-audio.com

I think the pcix slots are backwards compatible. But you would want to check that out first.

 

[dominicT]

Gary

I am about to buy an i-Book to archive most of my music and to compliment my Wadia transport and DAC. I will be using the i-Book as a transport with the Wadia DAC so thought that I would drop you a line.

You can of course use the analogue output but in my experience there is a significant upgrade to be made by using a DAC. You have two ways of achieving this. Either take the optical out of the MAC to a DAC, alternatively, buy an external soundcard (which is actually a DAC but called a soundcard).

Working on the basis that you buy at worst a G4 then you will have a USB port that will allow you to upgrade the soundcard with an external soundcard unit. This will enable you to bypass the internal soundcard and possibly get a better result for your budget. You will be able to borrow an external DAC from any reputable pro-audio dealer (Joel suggests M-Audio and I would agree) and also borrow a DAC from a hifi shop (or mate) and compare them.

A consideration about buying an external soundcard for your MAC is to buy one with a digital out. This means that you have more options for future upgrades ie buy an external (hifi) DAC. You would still use the external soundcard and use its digital output into the digital in of the Hifi DAC. This is the route that I have gone down.

The MAC has a firewire port and you could buy a firewire external soundcard. This will facilitate a long cable run far better than a co-ax cable run.

You made the statement "my assumption is that a DAC should not be offering anything to the sound, rather converting the signal with as little loss as possible?" I would not agree with this statement - I have found significant differences between both hifi DACS and soundcards. Have a listen and see what you think. I also suspect that the MAC with an upgraded soundcard or by useing an external DAC could give your Naim a run for its money. My MAC/Wadia would certainly beat it (based on my actual comparisons - I bought Wadia over the Naim).

Let us know how you get on.

Dominic

 

[garyi]

Thanks Dom.

I have now bought the G5, and look forward to the fun I might have with it!

My finace is now saying she prefers a 'proper' CDplayer for cd play back, but I would still like to look at this as a serious contender. I will keep you all posted.

 

[joel]

Gary,
I think you'll have a lot of fun with the G5.
Analog is cheap and easy until you find a better solution.
Looking forward to hearing how you get on.