How good of a DAC is the Logitech Transporter

Okay Rich fair analysis, I am curious with the thought, when I spoke to a tier 2 Logitech technical rep. they mentioned the only difference in sound would be 96/24 domain. As a Electrical Engineer, I follow your process of elimination and trust your integrity as a end user and the real world with the associated in-out circuitry that you based your test on.

Again thank you for your support on this issue.

Hi Audiogalore,

I'm not surprised he said that, he's probably a support tech answering the phone (I have no idea), however even engineers who are not audiophiles like yourself, don't understand the reasons why these differences occur. I know some very bright non-audiophile engineers, that don't understand why more expensive cables and interconnects sound better then cheaper ones, and some of them can't even hear the differences.

The Transporter was specifically designed to satisfy us audiophiles, according to the original company Slim Devices which was bought out by Logitech a few years ago.

If you go to the Logitech website take a look at the specifications of each.

The only thing that I could ascertain from the Transporter specs are as follows:

Word clock input for synchronization with an external clock
Linear-regulated power for all clock paths
Dedicated high-precision crystal oscillators (no PLL, no resampling)
Standard IEC-958 (S/PDIF) or AES/EBU encoding
Optical connector: TOSLINK 660nm
RCA connector: capacitor-coupled 500mVpp into 75 ohms
BNC connector: transformer-coupled, 500mVpp into 75 ohms
XLR connector: 4.7Vpp into 110 ohms

So, if Word Clock synchronization, lower jitter, larger linear regulated power supply, higher signal to noise ratio, a 110 ohm XLR digital output, a larger and heavier chassis, and the ability to upgrade the power cable, all doesn't make a difference according to Logitech, than I'm not sure why they are charging $1600 more for the ability to use a 24Bit/96khz DAC, which I don't even like. This is all tongue and cheek of course.

I've been an audiophile for over 25 years, and I am absolutely positive of my impressions, and I actually believe that you would bet on me instead of that Logitech Technician. The simple fact that you could appreciate the weaknesses of your squeezebox, tells me that you too will also enjoy a Transporter just like I do, especially through the 110 ohm digital output.

I have some really nice gear, there is no way that I would ever have thought that I would be using a Logitech Transporter as my Digital front-end source. I'm telling you..... Faaahgetaboutit...., it wasn't even close, the Transporter destroyed the Squeezebox.

I will also tell you that as more high-end companies start focusing on Digital Streamers, then I will probably upgrade to one of those products down the line. Right now its, Linn, Soolos, Logitech, Sonos and the PS audio which isn't even available yet.

Rich

Rich you are absolutely right not because I am a Engineer certifies me an expert on the sound of ones and zeros. As matter of fact trial and error is the best test. Example and proof is your total demonstration that we all testified today and that alone is money to the bank.

I guess my dilemma is that I do not have balance inputs on my Melos 333 line pre-amp. and I know there will be some degradation taking balance out of the Transporter directly to my Power amp. I believe this month Absolute made mention of same.

We all know as we speak there are changes being made to the next generation digital and that eventually Red book CD as we know it will die. At present after numerous research on digital front end the transporter is the closest to getting it right.

Audiogalore Quote: "I guess my dilemma is that I do not have balance inputs on my Melos 333 line pre-amp. and I know there will be some degradation taking balance out of the Transporter directly to my Power amp. I believe this month Absolute made mention of same."

Yeah, I'm still here!

You don't have a dilemma. I believe that the Absolute Sound Article that you are referring to was talking about using the Analog Outputs of the Transporter, (either balanced analog out or unbalanced analog out) which implies that you will be using the Internal DAC of the Transporter and therefore, if you were to go directly into a power amplifier, then you would be forced to use the digital volume of the Transporter which can trump bits and cause a loss of resolution.

From what I gathered from you, this is not what you will be doing. You will be using the 75ohm SPDIF Digital Outputs of the Transporter to your external Tri-Vista DAC, then to your Melos 333 Preamp using your analog RCA Cables. So, you will be able to put the digital volume all the way up on the Transporter (so not to lose any bits of resolution) then you will be using the Analog Volume Control on your Melos Preamp. You will not be losing anything except the difference between a 110 ohm digital cable (because your DAC doesn't support this) and a 75 ohm digital cable, as well as the difference between a fully balanced Preamp/Amp setup, but you don't have that now, so you won't lose anything.

I was using a 110 ohm AES/EBU Digital Balanced Out Cable (which is a single Digital Cable) from the Transporter to my external DAC, not a Balanced XLR Analog out. The digital cable that you will be using is a single 75 ohm Digital SPDIF Cable.

Does that make sense?

Rich

Thank you for the correction, I some how lost track of myself and started to thinking about the internal DAC and got ahead of myself. I really meant to to say the digital output of the transporter. Rich I have been doing this wacy hobby too long approx. 35 year it known as a "senior moment". You are correct the downside of the TRI-VISTA it as minimum inputs/outputs, oh well that is the Brits for you!