Highest quality AES-EBU

[20hertz]

I wish to implement the highest quality AES signal i can acheive. Unless a USB converter like the Legato exists i think I need a desktop with direct AES out [ to big for laptop].

What options should i look at?

Thanx

 

[catastrofe]

I use a Lynx AES16e in my Mac Pro. I believe this is also what Chris uses.

 

[The Computer Audiophile]

Hi 20hertz - Yes, I use Lynx AES16 and AES16e cards. They have many advanced options that I thought I wouldn't use but have since taken advantage of many of the options. Another card I've heard great things about is the RME HDSP AES-32. These two cards are expensive but offer high quality.

 

Right now the absolute highest quality can be obtained using a Merging Technologies Mykerinos card. The cards are several thousand dollars and require Pyramix mastering software to play audio. I have one here but the complete consumer solution is not commercially available at this time.

 

Cheaper options do exist like the ASUS Xonar Essence STX. This is a really nice card for less than $200.

 

[20hertz]

There is an interesting thread re Lynx cards on the Asylum. The Mykerinos looks good but the price is just out of reach at present. I am not a fan of USB but the Legato looks well thought out to me, but no AES. I plan to assemble a complete server so starting from scratch.

Thanx

 

[Urs]

You could also think about a laptop + firewire ExpressCard + Weiss INT202 firewire interface

 

A Lenovo T500 with an Intel SSD is both: powerful and completely silent

The ExpressCard should have a TI chip

 

[20hertz]

I have considered this option, it well be the cheapest and easiest, despite the high cost of Weiss. Does firewire offer a decoupling electrically from the computer? Are there great firewire cards? Thanx for your help.

Mike

 

[Suteetat]

I think the only way you can electrically decouple the couputer from DAC is by using Toslink. Firewire and USB would still be electrical signal. Alternatively Weiss Chiron digital cable convert spdif to some sort of optical signal via glass fiber or some kind of fiber optic then at the other end is converted back to spdif again so it would be the only kind of spdif connection that decouple electrically and not using toslink.

 

Cost of Weiss NT202 firewire interface is not actually that bad if you look at the cost of high end AES/EBU digital cable. They can run around $2000+ or more per meter. Siltech firewire cable are available at $1000 and $1800.

Of course I am not saying that they are the best since I never heard them.

 

I think Weiss recommend any firewire card that has Texas Instrument chips.

 

 

[manisandher]

Yesterday, I managed to find some time to compare the SQ of the Weiss AFI1 (firewire) interface with the RME AES-32 (PCI) card. All listening was done with the PMII in Master mode, i.e. the wordclock was not being derived from the signal being carried in the AES cables. Although I couldn't use exactly the same AES cable for both devices (the RME requires a 25-pin D-sub breakout cable, the Weiss doesn't), I did manage to use the same type of cable - 110 Ohm Sommer cable.

 

The first thing that struck me was how different the two devices sounded. The Weiss sounded sharper, more upfront and had more 'ambience'; the RME way more mellow, laid back and had a darker background. Although the difference itself was obvious, which one was actually better was not. I'm sure many people would opt for the Weiss - my inclination was more towards the RME.

 

But I really wanted to understand what could be causing such a big difference in sound between the two. So I tried changing a few things... and then stumbled on something that really surprised me.

 

You see, the RME has two settings for the peak-peak voltage of the AES signal: 5V/professional and 2V/consumer. (Incidentally, these voltages fall within the AES-3 specs of between 2-7V.) And low and behold, I could pretty much simulate the difference I was hearing between the Weiss and the RME, the 2V setting sounding very similar to the Weiss.

 

So, what is going on here? A few possibilities:

 

1) The 5V setting is increasing the SNR.

2) The PMII is reacting differently to the two AES voltages.

3) The RME card is struggling to provide a true 5V signal at high (MHz) frequencies and is happier outputting a 2V signal.

 

Any thoughts?

 

Mani.

 

[earflappin]

Mani, interesting experiment. Hopefully someone expert in this area can weigh in with comments. BTW, have you ever tried an Antelope DA to provide AES noise isolation for your Model 2? The Alpha DAC sound quality is definitely improved (it is not subtle) when using such a device in the signal path.

 

20hertz, based on recent experimentation with my Lynx AES16 versus the Legato I think you are likely to get the lowest jitter/lowest noise AES output from a computer server using a well designed outboard async USB (or firewire) to AES converter. Why? They use better clocks, power supplies and provide galvanic isolation. I suspect a big reason why the Merging soundcard sounds so much better than the Lynx is that they have done a better job of addressing these issues.

 

Elsewhere on this site and on other forums it has been stated that Berkeley will be coming out with an async USB-to-AES converter later this year. Of course there is the Weiss firewire-to-AES/SPDIF converters. Also, the new Antelope Zodiak Plus (est price of $2500) will do async USB-to-AES, as well as having its own high quality DAC.

 

If you elect to go with a Lynx or RME AES sound card then I would recommend an Antelope DA to provide noise isolation, unless you are sure your DAC is immune from incoming noise.

 

 

[manisandher]

"... I think you are likely to get the lowest jitter/lowest noise AES output from a computer server using a well designed outboard async USB (or firewire) to AES converter."

 

Well, this is exactly what the Weiss AFI1 is... and I'm not sure it sounds better than the PCI RME AES-32. I actually prefer the latter (when set to its 5V/professional AES output) right now.

 

I'm not sure the clock has mcuh to do with things either, in my case at least - I have the PMII set to Master, so its [high quality] clock, sitting right next to the DAC chips, is doing all the work.

 

Incidentally, the RME has a transformer isolated wordclock input and also has transformer-balanced & ground-free AES inputs/outputs. Would the Antelope DA provide any improvement here? I may just have to try one and find out!

 

Cheers,

Mani.

 

[hifitubes]

What is the test to determine of the DAC is noise free?

 

In my case, with my bad motherboard, with the DAC hooked up I could hear EMI or power noise instantly at the speakers, on the couch 8ft away for that matter. Many live with small amounts of hum sometimes or powerline noise with our tube amps etc. so what if we do hear a small change in the inherent sound signature, should we freak? I would advise freaking out if you have noise like I did with that motherboard.

 

At best we talking about sticking your ears right up to your drivers and turning on your PC (then your DAC etc.) and listening for noise, or....

 

are we implying there is contamination only during music playback which affects fidelity?

 

Interesting find Mani; it surely has to do with the voltage as you have observed. I have only in the past used an EMU 1616M which had no such switches for the digital i/o, only +4 vs. -10db for the analog i/o.