Fireface vs. Lynx AES16

[johniboy]

Hi!

 

I was wondering whether anyone could share his/her experience with comparing the digital output of a Fireface 400 (or similar firewire 2 spdif converter) to a high end soundcard like the Lynx. In several threads people were writing that keeping the soundcard out of the computer helps to improve the sound quality (computers are a dirty environment, etc). But did anyone do an A/B comparison? Is there a difference on the spdif digital out and if yes, how big is it? The price difference between the fireface 400 and the lynx is not that huge... Is there a way to improve the shielding of a soundcard inside the computer?

 

[PeterSt]

I have always been telling that no matter what you would do, with XXHighEnd nothing could be done to disturb sound. However, it appeared to me that this counts for the output of the (passed through SPDIF) of the Fireface, and certainly does not count for a PCI interface.

 

I must honestly tell that I am talking about 100% cpu useage or very heavy I/O, but a PCI interface just won't dig that. Crackling appears or sound may temporarily stall (like a few tenths of a second), and there is no way I ever experienced such a thing with the Fireface (800).

 

Notice that the crackling (vinyl like) is a mild form of sound degradation, and one degree less wouldn't exhinit crackling, but sure would degrade sound nevertheless. You can translate this into "don't use 100% CPU but a bit less, and crackling may not happen, but it still won't be good".

 

Hope this helps.

Peter

 

[johniboy]

You are probably right. Before i started to build a dedicated pc for music (and used a cheapo soundcard) I also noticed the crackling at high cpu loads. now, with my slimmed down dedicated dual core cpu it never happened again. The sound is already very good... the question is can it get better by taking the spdif connection outside the computer? How large are the differences between digital outputs of different cards (pci or firewire) anyway? Usually these tests are not performed in audio magazines. They usually test the analog outputs of the cards.

Any other on-hand experiences?

 

[PeterSt]

What I know is that using the SPDIF from the motherboard just sounds like cr*p, although it will depend on the motherboard and chipset I guess. It should be jitter impeeded.

 

Much will depend on the strength of the signal, the quality/length of the cable and such, and one thing an outboad soundcard does is taking away those "distance problems". For example, a 10 meter SPDIF coax really sounds bad, but a 10 meter Firwire + 1m coax is just OK. So it's not only the quality of the transmitter, but also the functional means of solutions.

 

Peter

 

[Tog]

Try a Mac

 

 

yours, tog

 

[PeterSt]

But that depends on your tooth paste, don't you think ?

 

[bordin]

The new RME Fireface UC (USB) looks very nice. It does 24/192.

 

The compact Fireface UC has been uncompromisingly optimized for highest performance under Windows and Mac OS. Based on a newly developed RME Hammerfall core the Fireface UC provides revolutionary ultra-low latencies even with multiple channels. It uses two different firmware versions with different transfer methods to remove current restrictions of typical USB audio interfaces. The unit's operating mode Win or Mac can be changed directly at the unit at any time. Under Mac OS the Fireface's MIDI ports are class compliant, the operating system therefore automatically uses the included MIDI driver.

 

Under both Operating Systems the available latencies are simply sensational. The smallest buffer offered under Windows has 48 samples, under Mac OS X 14 samples. With this RME provides a performance previously not available from USB audio interfaces.

 

 

[johniboy]

and another interesting soundcard! costs 900 EUR in Germany so its even cheaper than the other firefaces. it even has a micro preamp. would be great to listen to its digital output. ;-)

 

[bordin]

Hi johniboy,

 

I'm finding information about the Lynx16 and the FFUC. The Lynx is 1/2 price of the FFUC, given I need only the digital output for playback capability only. So, it would allow spending on a precision word clock module such as Black Lion Microclock.

 

[kana813]

Saw this on another forum:

 

"The RME Fireface products have a rather poor clock design relative to well designed audiophile products (although this design does give them excellent flexibility when used for their primary purpose, as a recording interface). They use a digitally synthesized clock frequency, which is adjustable over a wide range, rather than any kind of fixed clock. The specification for jitter RME gives is

[barrows]

I own a Fireface 400, and have listened to it extensively as both a firewire to SPDIF converter, and as a Firewire DAC from its analog outputs (balanced). The sonic performance in both cases is rather disappointing. My system sounds a lot better playing CDs directly from my transport into the same DAC used with the FF.

1 nS is a lot of jitter, as mentioned, audiophile DACs generally have below 300 pS of jitter, and the better DACs perform at less than 100 pS of jitter. My understanding, from speaking with digital designers I trust, is that a DDS is a poor way of generating a clock frequency: RME uses this method because it allows them to have a highly adjustable clock, allowing the FF products to sync up with many different sources. This flexibility comes at the price of high jitter, hence RME's specification of

[bordin]

Thanks kana813 for information.

 

"They use a digitally synthesized clock frequency, which is adjustable over a wide range, rather than any kind of fixed clock." I came across the following article (RME ads 2005).

 

RELATED TECHNOLOGY Against the clock Unusually for a soundcard or audio interface, the Fireface doesn’t derive its digital internal clock from a quartz crystal. Instead, the Fireface uses a unique Direct Digital Synthesizer (DDS) to generate a more stable clock, with greater precision and flexibility than the quartz crystal offers. Controls for the DDS can be found as part of the Fireface Settings Control software (under the DDS tab). In most situations you’ll want to leave this set at 44.1kHz or 48kHz, but situations can arise whereby it is desirable – or even essential – to change the sample rate. Strange sample rates are often encountered in the video industry or, alternatively, you might want to retune your DAW to match different continental instrument tunings – orchestras in Prague, for example, play at A=438Hz rather than 440Hz.

 

http://www.soundworks.dk/RME-PDF/music_tech_Fireface_800.pdf

 

Below is extracted from the FF400 User's Guide, page 60.

 

But word clock is not only the 'great problem solver', it also has some disadvantages. The word clock is based on a fraction of the really needed clock. For example SPDIF: 44.1 kHz word clock (a simple square wave signal) has to be multiplied by 256 inside the device using a special PLL (to about 11.2 MHz). This signal then replaces the one from the quartz crystal. Big disadvantage: because of the high multiplication factor the reconstructed clock will have great deviations called jitter. The jitter of a word clock is typically 15 times higher as when using a quartz based clock.

 

The end of these problems should have been the so called Superclock, which uses 256 times the word clock frequency. This equals the internal quartz frequency, so no PLL for multiplying is needed and the clock can be used directly. But reality was different, the Superclock proved to be much more critical than word clock. A square wave signal of 11 MHz distributed to several devices - this simply means to fight with high frequency technology. Reflections, cable quality, capacitive loads - at 44.1 kHz these factors may be ignored, at 11 MHz they are the end of the clock network. Additionally it was found that a PLL not only generates jitter, but also rejects disturbances. The slow PLL works like a filter for induced and modulated frequencies above several kHz. As the Superclock is used without any filtering such a kind of jitter and noise suppression is missing. No wonder Superclock did not become a commonly accepted standard.

 

The actual end of these problems is offered by the SteadyClock technology of the Fireface 400. Combining the advantages of modern and fastest digital technology with analog filter techniques, re-gaining a low jitter clock signal of 11 MHz from a slow word clock of 44.1 kHz is no problem anymore. Additionally, jitter on the input signal is highly rejected, so that even in real world usage the re-gained clock signal is of highest quality.

 

I'm not sure whom to believe. ;-)

 

 

 

"The specification for jitter RME gives is

[bordin]

Thanks barrows.

 

I had a chance to audition my friend's Lynx AES16e against my Juli@ card and M-Audio Firewire Solo in his system. The Lynx won hands-down !!

 

My friend's reference transport is his Linn Genki, heavily modified i.e. Superclock 3, OPA627BP, caps mod (Blackgate+Oscon), Phython PSU x2 (seperate digital & analog sections) & AES digital out installed.

 

This transport sounds the best I've ever heard ! The Lynx can get around 80% of the Linn. I've compared the C.E.C TL2 against the Linn and found similar results. Choose the Linn ! The player is cPlay, BTW.

 

I don't know whether the PSU, the Superclock, the caps or all of them that make the Linn transport sound so fantastic ! It is very balanced and detailed, simply more musical.

 

I wish I could find a computer transport at that level but still haven't found one yet. The Fireface 400 seems to be a good choice unless it doesn't do things right.

 

[untangle]

I own the RME FF400 and have used it as my reference for months.

 

I have listened to the Lynx soundcard many times. Regrettably, esp for this conversation, not on my reference system. (I'm a "Mac guy.") Properly set up, I believe it to be it is a reference-class component.

 

Here are some observations:

 

1. The RME is easy to set up and get good results. RME drivers are solid, as is the management software. Firewire works like a dream, already embodying the features and performance that seems to elude USB systems. My system is relatively immune to what's happening on my Mac Mini. I can run other app's and listen at the same time.

 

2. DDS in the RME products is an optional feature, not an intrinsic part of operation. The default is OFF. I can't think of a reason why an audiophile would use it. It's a pro thing.

 

3. All digital products that I have encountered have benefited by quality clocking, usually (but not always) in the form of a word clock. I am well aware of the theoretical implausibility that an external word clock could better and internal crystal. But theory simply doesn't jive with my experience/ears. I would very much recommend the FF400 owners try a quality word clock. The same goes for Lynx owners. As 'they' say, the difference is not small.

 

4. Scaler jitter specs are not very helpful. Not all jitter is equally audible. The distribution of the jitter is a far more useful diagnostic than a single metric.

 

For the record, my signal chain is Mac Mini -> (via firewire) -> FF400 -> (via AESBU) -> Berkeley DAC -> (via XLR) -> Goldmund Monoblocs -> eFicion F300's. The FF400 is fed timing via a custom word clock. The BADA has a custom master clock and custom single-ended analog output stage. I use 'Play' to feed the music.

 

[EDIT] I run the RME, all clocks, and the BADA analog stage from battery. [/EDIT]

 

 

[cfmsp]

Untangle,

Can you please explain more about your custom master clock in the BADA?

 

I can only infer (from your choice of word 'master clock') that you are using the BADA to drive the clock in the Fireface.

 

If so, quite a few people might be interested in your approach.

 

thanks much

Clay

 

 

[untangle]

By 'master clock,' I meant the clock that actually drives the DAC chip. In the case of the BADA, this clock operates at a frequency of 25.5760 MHz.

 

As I was unable to find an off-the-shelf oscillator with requisite performance (10 PPM, 15 pF, etc.) and form factor (HC-49/U), I had 500 pieces fabricated in China.

 

I then asked Oritek Audio to design and implement a low-phase-noise clock circuit (similar in concept to a Superclock, but tighter specs). This piece is then installed as a battery-powered daughter-board in the BADA.

 

The results are exceptional.

 

For the RME, I use a custom Oritek word clock, designed in a similar manner and operating in the standard freq's (44, 48, ..., 192). Also battery powered. Works great.

 

Driving the RME from the BADA clock would be possible (after suitable freq-dividing), but would likely not improve this architecture dramatically.

 

I drive the RME using a third battery.

 

Bob

 

 

[cfmsp]

 

 

That's quite a lot of customization.

 

thanks for sharing,

clay

 

 

 

[hifitubes]

Bob's success with the RME device seems to gel with my interpretation of this:

 

"The actual end of these problems is offered by the SteadyClock technology of the Fireface 400. Combining the advantages of modern and fastest digital technology with analog filter techniques, re-gaining a low jitter clock signal of 11 MHz from a slow word clock of 44.1 kHz is no problem anymore. Additionally, jitter on the input signal is highly rejected, so that even in real world usage the re-gained clock signal is of highest quality."

 

The jitter spec (prior to quoted para) is probably with internal clock on RME, no? What RME is saying is that they can sync to external clocks with a very high degree of accuracy now...?

 

Bob, I also assume you meant you are using S/PIDF output on the Fireface; I don't see an AES/EBU output on those units.

 

thanks,

hifi

 

[untangle]

1. I'm not positive what the RME docs are alluding to, but the comments are relevant to sync'ing the internal clock with an external one - whatever the source (SPDIF, AESBU, or word clock).

 

2. I drove the Alpha DAC via a (software-selectable) AESBU signal transmitted out the RCA (and into the Alpha's XLR).

 

Cheers,

 

Bob

 

 

[Bob Stern]

An interesting aside is that Bob W. ("untangle") found that the BADA uses a 25.5760 MHz clock regardless of audio sample rate. This implies that the BADA DAC uses asynchronous sample rate conversion to convert all sample rates to 192 KHz.

 

This would eliminate the possibility of synchronizing the clock of the S/PDIF converter or sound card to the BADA clock when playing 44.1, 88.2 or 176.4 sample rates.

 

[manisandher]

If true, this would explain why there is no wordclock output from the BADA... which is a shame.

 

IMHO, a wordclock output would have been a better solution to containing jitter than having to resort to ASRC (if indeed that is why ASRC is done). This especially true when you consider that so many people use a Lynx card (with which to feed the BADA)... which of course has wordclock I/O!

 

Mani.

 

[untangle]

The lack of WC-out on modern (high-end consumer) DAC's is indeed unfortunate.

 

Given the Pacific Microsonic roots of the BADA team, I suspect that their decision was market(ing)-driven:

 

1. Few consumer upstream components have WC I/O.

2. Cost issues

3. Messaging issues (...if your jitter-rejection scheme is so good (it ain't), why do you need WC-out...)

4. Nobody else does it

 

IMO and IME, clock management holds the best promise for further sonic breakthroughs in digital. (And many assumed truths don't pan out in listening tests...)

 

Bob

 

 

[hifitubes]

I guessed you might have been using AES/EBU over RCA like the EMU cards allow, but was sure.

 

I have decided to go the Lynx route. I was going to use a battery powered MOTU limited to 96kHz, but had independent word clock i/o and AES i/o which is only found on Weiss AFI-1, Konnekt x32, and the Mac only ...uh can't remember the name.

 

I can't go USB DAC now because my vinyl playback is likePureVinyl but on Windows and I need ASIO to do realtime monitoring of my input (to pally digital RIAA in Samplitude). I have tried with hiFace and Musiland devcies and they don't allow this.

 

SO, I'm going run a Macroclock (modded BLack Lion audio Microclock) distributing word clock independently to a Mytek ADC 192 and the Lynx, then ffed my DAC via AES from Lynx. The Mytek and "Macroclock" will run on battery.

 

Sorry to hijack your thread, but I'm excited to have finally settled on my "upgrade".

 

cheers

hifi

 

 

[untangle]

sounds like a plan, hifi. (enjoy!)

 

the black lion is excellent kit.

 

so is pure vinyl.

 

bob

 

 

[hifitubes]

Thanks! It was feeling convoluted going the MOTU route, and those units have reliability issues according to Black Lion (they won't mod them any more) so a new 775 dollar unit would be needed. I don't need a Firewire card now, and I don't have to dive into something (MOTU) I am unsure about.

 

I hear over and over how external cocking will just make things worse. If you use proper terminations/cables it should work. BLA wants to sell their clock, but they seem pretty honest to me. Jitter performance improves with external clock according to them, and they use $30K devices to analyze what is spit out the transport/DAC. And it seems to gel with what recording industry professionals experience.

 

If I could have something like a USB DAC or HiFace transport, I would probably use it, but as I sadi, I'm sort of stuck because I need ASIO to do digital RIAA on Windows with Samplitude. Now I'll be able to try 192kHz too.

 

wish me luck - I may have quest5ions too as I have never used a Lynx, just EMU devices & M-Audio.

 

hifi