Starting up a new system

[cmason16]

Well I am about ready to make the plunge. My planned system will be:

 

Mac G5 Power PC (already own it)

Lynx AES16

Custom cable (20 feet long) from Redco Audio

AES16 feeding a Benchmark DAC1 USB (already own it)

 

I am working on voicing the living room in accordance with Jim Smith's book "Get Better Sound" and will be using a Intel MacBook based real time analyzer (either FuzzMeasure or RoomEQ) along with my ears. My system is set up for home theater with a Sony DA5200ES reciever. I may switch my Rotel RSX 1065 back in once I get it worked on. Mourdant Short speakers. Not the ideal based on Jim Smith's book, but what I have. I will look at changing out components once I have these working at their best.

 

I initially started re-ripping my CDs to Apple Lossless, but my switch to AIFF since I am not that far along. I will be starting off with a 500GB Lacie drive for file storage.

 

So the questions I have from reading here and other places are:

 

Any pointers regarding the Lynx set up for feeding the DAC1 USB? The clock discussions have me a bit confused.

 

Options other than the Lynx that would work with an Intel based MacBook? I ask this since Apple may not be releasing the next version of OS-X for PowerPCs. But the above should still work fine for several years and by then who knows what the hardware market will have.

 

One thing I am looking into (I have access to some of the Apple engineers) is if there is a command line ability to set the Audio Midi Setup. If I can get that working I could set up a single mouse click script that would switch itunes from sample rate to sample rate. I am also looking into the possibility of an Audio Unit plugin for iTunes that would enable auto sensing and setting of the sample rate. From Apple Core Audio developer documentation it should be possible, but then I am not a developer either.

 

Look forward to comments on my two questions and feed back on the sample rate conversion effort.

 

Till later,

 

Chuck

 

 

 

[Roseval]

Any pointers regarding the Lynx set up for feeding the DAC1 USB? The clock discussions have me a bit confused.

As far as I know, the DAC1 has no connection for word clock so it will sync to the SPDIF input.

 

Before you spend 600,- on a sound card, anything wrong with the USB input of the Benchmark?

There are 2 brands often mentioned when talking top PCI sound cards, Lynx and RME, check http://www.rme-audio.com/english/hdsp/hdsp9632.htm

 

[tfarney]

I think that set-up will sound great, but I think it would probably be just as great without the soundcard and the custom wire. Got an Airport card in your G4? Plug an $80 Airport express into the wall behind your system, run an optical cable to a DAC and give it a listen. If it doesn't sound as good or better than your cdp, you can always return the AE and go the expensive route. The odds are very good, though, that it won't buy you much, if anything.

 

Tim

 

[cmason16]

Thanks for the comments,

 

I currently am using airtunes to transmit to an airport express that feeds the DAC via optical. The Airport limits out at a 96 sample rate. I checked and the MAC audio drivers for ALL outputs on the built in audio max at 96. No issues at all what I have now, but I guess I am a closet audiophile, I just have to hear what the HRX from refrence recordings sounds like. To do faith to the quality of the materiel I need to take it up a noch. Just wish I could swing a Berkley DAC, oh well maybe later.

 

One question - I have read a bit here about the sampling rate in regards to frequency that a human can hear. I thought the sampling rate is the number of times per second that the audio source is sampled and a digital "copy" in 0s and 1s of that moment in time is recorded. The lower the sample rate the less total information when compared to live. Although I have not heard just what sample rate the human ear / brain runs at for comparison. We "see" at about 4,000 dpi (I think), what do we hear at? So just what is sample rate? My stupid question of the hour.

 

From my reading of the DAC manual it appears that I do not need to worry about the clock issue. I just need to get the AES16 to output on a single XLR 110 ohm cable. I did pickup that my G5 Quad 4 with 16Gig of memory can support the AES16e, which would also work in an Intel Pro if I go there in the future.

 

Hopefully someone drops me some info on the AES16 configuration process if there is something not obvious in the install manual.

 

Till later,

 

Chuck

 

[Mr.C]

The plugin for itunes sounds like a great addition if you ever find one. The Weiss Vesta (firewire to xlr) would work with a MacBook Pro, or one of the last generation macbooks. Chris also mentioned a usb to spdif converter by Musical fidelity I believe, that would fit the bill for 24/192. As mentioned earlier, the DAC1 will receive the timing dictated by the lynx clock, so maybe you could be a little more specific in your question if you are still confused.

 

As a side note, how does the dac in your receiver compare to the dac1?

Also, is the sony receiver your primary amp? If so, you might notice more sonic improvement by upgrading there rather than buying the $700 lynx card (I'm thinking a used or new rotel rb-1080 or something along those lines). Or does it sound good as is? my 2 cents anyways.

 

[Roseval]

Our audible range is 20 – 20.000 Hz.

Mathematically a sample rate of two times the highest frequency is sufficient to reconstruct the analogue signal. Include some headroom (filtering) and you need 44.100 samples (per channel) to cover the audible frequencies.

 

 

[cmason16]

My Apple contacts are looking into the ability to use terminal commands to set Audio Midi Setup. This enable the process to change sample rates to be greatly simplified, down to a one button click. I should have some feedback this week.

 

The auto sensing should be doable via an AU to iTunes, but I do not know if I have the time to come up to speed on writing it.