Critical elements for hi-rez music streaming?

Rogerwalk: "I stream the wav files through a network router to a different room where a network player/bridge (Logitech transporter)decodes the WAV files and sends it via S/PDIF cable to a Meridian G68 XXD pre/processor which in turn converts the signal with its 24bit/96kHz DACs into an analog signal for the amplifiers and speakers."

Rogerwalk: ""But going through two cycles of D/A conversion defeats the idea to stay in the digital domain until the processor. ""

Can you explain to me where there are two cycles of D/A Conversion? Because unless I'm missing something in your explanation, I only see one D/A Conversion.

Your connection should be Transporter digital out to your Digital in of your Audio Synthesis DAC-2 and then Analog out of the DAC-2 to your Meridian G68 Analog input, then your Meridian would be acting as a source selector and line-stage at that point, and not performing a second D/A conversion. Furthermore, if you are using digital out of the Transporter then you are bypassing the Transporters DAC. The only D/A conversion that I see in my above example, would be your DAC-2.

Rogerwalk: ""Do you have any insights in the sound limitations that are caused by elements before the transporter? I thought the transporter with digital in and digital out is not likely to negatively influence the sound quality, but the elements before are.""

Yes absolutely, you have everything before the Transporter set up correctly, there should be no sound limitations as far as I can tell in your setup, as long as you have the Digital Volume all the way up on the Transporter.

When you say," the Transporter with Digital in....." above, are you referring to the Ethernet Cable as your digital in? If not then what are you referring to in your above statement when you state, "I thought the transporter with digital in and digital out is not likely to negatively influence the sound quality,......." Do you have a second digital cable into the transporter and if so, then where is it coming from?

Some suggestions would be to try the Internal Transporter DAC on its own then feed the analog out of the Transporter to the analog in on your Meridian and let me know how that sounds, and also try the SPIDF interface on the DAC-2, since the AES on the Transporter is currently non-functioning.

You can use your Forsell/Dac-2 as the reference, although I think your Audio Synthesis DAC-2 is very old, possibly over 12 years old, is this true? If so then it's time for a new DAC Buddy! Unless you like the internal DAC of the Transporter which should out perform much older DAC's.

Let me know what's up!

Rich

Unless the internal AKM DAC of the Transporter simply out of the question, consider a ModWright Truth mod that adds a tube staged output. You can tweak the sound quite a bit by rolling tubes and shorten the signal path in the process.

Thanks, Rich, again for your time to dive into this.
The two D/A conversion cycles occur when the Audio Synthesis DAC-2 converts the digital signal from the Forsell transport to analog, sends it as analog to the Meridian pre/pro which in turn converts EVERYTHING that goes in into a digital signal. The Meridian then converts the digital signal with its 24bit/96kHZ dacs to analog for amlifier/speaker output. There is no analog pass through the Meridian pre/pro.
When I use the Lg Transporter passing the digital signal from the Ethernet cable/network (this is what I called 'digital in') to the Meridian digital input, the only D/A conversion takes place in the Meridian for its analog output.
Re the 'aged' Audio Synthesis DAC-2: Sorry, but age alone is not a reason for lack of performance with Redbook CD material (16bit/44.1kHz). I have "challenged" the old Audio Synthesis with most modern DACs in the price range up to the $4,000 (the original price of the DAC-2) me and there is simply no reason to retire it at this time. The combo Forsell/Audio Synthesis DAC-2 just declassified in my system the ultra-modern highly acclaimed PS Audio PerfectWave transport connected directly with the Meridian pre/pro. I did not test the transporter DAC though (I explained earlier that the XLR port of the transporter was defect).
So what about the influence of the router on the sound? Is bandwidth not an issue for streaming hi-rez audio files to the transporter? What about the optical drives in our PCs? Does it matter? Why does the same CD ripped and played through the transporter not sound as good as when its played on the Forsell/Audio Synthesis combo??

great thread guys. roger, how is life in paradise!?

i am very curious about the router question as it is something i have wondered too. i literally paid like $35 at walmart as i never thought i would use it for audio. now it seems as if it should be an important part of the process but i know nothing about whether it's quality impacts what i am hearing.

i have the same issue with digital conversion, i use a theta casanova which converts everything to digital with no analog pass through. if i was to use an external dac i would need a preamp with a ht pass through. that would solve your problem leaving only one d/a conversion, correct?

Hey Roger and Richard,

"So what about the influence of the router on the sound? Is bandwidth not an issue for streaming hi-rez audio files to the transporter? What about the optical drives in our PCs? Does it matter? Why does the same CD ripped and played through the transporter not sound as good as when its played on the Forsell/Audio Synthesis combo??"

Roger,

I'm following you now, however I'm shocked to learn that your Meridian Pre/Pro doesn't have an analog pass-through.

Bandwidth streaming and buffering can certainly be an issue wirelessly, but if you use a wired ethernet cable, then it should not be an issue.

Optical drives can be an issue if you accidently knock into the side of your computer while you're ripping your CD's, especially with a laptop, otherwise they're pretty solid. I have error correction checked in iTunes importing preferences. I also keep cross fade, sound enhancer, sound check, and equalizer settings all off. I would not be surprised if a high-end CD burner hooked up to a computer would out perform a $50 plastic drawer CD-R Drive. When using digital output on a computer directly into a DAC, you will need to have the master volume on the computer and in iTunes all the way up, as to not trump resolution.

When you run the DAC-2 and the PS Audio DAC, through the Meridian Pre/Pro and it undergoes another A/D then D/A conversion by the meridian, then everything that comes out of the Meridian will have a similar sound to the Meridian. So, I'm thinking that it probably doesn't matter what DAC you use, since they should all sound like the Meridian, however you say the the DAC-2 always wins the DAC battle. I'm not sure why this would be the case, but it is what it is.

I think if you want to take your system to the next level, then you will probably need to purify your 2 channel Analog Signal coming from any "NEW DAC" that you may settle on, and then get some type of Analog Linestage/Preamp with an Analog Home Theater Pass-through.

No wonder you think the DAC-2 is still good, because in my opinion it's acting like a bridge to your Meridian instead of a DAC.
The DAC's that you're trying, like the PS Audio or Transporter are not being able to shine through because the Meridian is acting like a Big Fat Bully!

Yes, Correct Richard, you need a Preamp/Linestage too with a home theater pass-through. The Theta and Meridian are two of the best processors out there, however they need to step aside and let the sunshine through! I'm only saying this because you guys are trying to better your current systems, if you were thrilled with your set-up, then I wouldn't be suggesting additional equipment.

Ok, If Routers and Ethernet cables matter, then I'm just gonna shot myself. I could just see it now, "Bel Canto is proud to announce its new High-End Audiophile Quality, Tubed Wireless-N Router with gold connectors, and battery operated." Or, how about Kubala-Sosna is proud to introduce its brand new line of Ethernet Emotion Category 6 Cables for $2000 per meter."

Roger: ""So what about the influence of the router on the sound? Is bandwidth not an issue for streaming hi-rez audio files to the transporter? What about the optical drives in our PCs? Does it matter? Why does the same CD ripped and played through the transporter not sound as good as when its played on the Forsell/Audio Synthesis combo??""

For one, I think you mentioned the you were using AES 110 ohm balanced for the Forsell/DAC-2 and I know that the Transporter as well as the Squeezebox are weak in the 75 ohm SPDIF Output. There may be other differences, like better power supplies, cabling, and isolation in the other equipment, and possibly a comfort level of a sound that you're used to. Your not using a pure signal, so all bets are off.

The reason I'm comfortable with my findings, has to do with the following:

I've ripped all of my CD's on a MacPro Tower, using Apple Lossless and iTunes, and I have a Netgear Router, and I'm using the Ethernet over Power-line protocol to run the signal wired through my house wiring inside the walls and then into the Transporter using a "cheapo" ethernet cable, then the signal goes Digital out using Kubala Emotion AES/EBU to an MBL 1611F DAC, to an MBL 6010D Preamp, to a pair of MBL 9008A Monoblocks, to Kharma Mini Exquisite Speakers. I use all K-S cabling, I have no power conditioning, nor do I have any room conditioning, I don't have a subwoofer, nor do I have expensive equipment racks, although I plan on getting some next year.

All I can tell you is that the sound that I am getting from this rig, is nothing short of extraordinary. It is probably one of the two best systems that I have ever heard, and I've been doing this for at least 20 years.

I'm going to be a little repetitive here, but I see this question asked a lot, and that is," If the Transporter is as good as your Forsell (or a very good transport)? "...., but the short answer is, Yes, that I have compared it to an MBL 1621A Transport feeding an MBL 1611F DAC, and although the MBL 1621A transport was marginally better it wasn't worth writing home about. I only use the Transporter as a streamer and not as a DAC. I could probably move your speakers 2 inches and it will make a bigger difference. This is why I'm pretty confident to say that I feel that the ripping method that your using, to the router and so on, is not your problem. It's all of the other things that I've mentioned, starting with your lack of an Analog Preamp/Linestage.

FWIW, I think the Squeezebox using its 75ohm SPDIF, is terrible as a high-end streamer, and the same goes for the Transporter using its 75ohm digital SPIF output, however, I seem to be the only one who talks about it. I have never even seen it mentioned in any one of the many Transporter/Squeezebox reviews.

Bottom line is that in my opinion, the Transporter using its 110 ohm AES/EBU digital output as well as an upgraded power cable, is one of the best transports currently available. However, there's not much competition right now, so I expect things to heat up!

About 15 years ago people thought that digital cables didn't matter, but obviously they do. My prediction is that you will be seeing high-end; Routers and Ethernet Cables shortly.

Not Proofread to expedite posting!

Rich