I am a little confused about something here. This dac appears to have only a USB input, right?
It seems like quite a handicap to compare that with the usual digital inputs of analog coax or optical... |
I would have to agree with Trebejo. |
Excellent question / observation regarding the dac's input choice.
db Audio Labs purposely chose not to include the interfaces suggested for very specific technical and MOST importantly, sonic reasons! Basically, for all the interfaces you suggest, some form of circuitry, albeit a chip or discrete componentry, must be included which connects to each of those interfaces and provides an I2S output signal which in turn provided to the dac chip.
So, in essence, each and every interface that you suggest (as well as the USB interface) must output an I2S signal to the dac. Typically, some sort of switching is used to select the respective I2S signal the interface desired. In order to optimize the I2S connectivity to the dac chip, the I2S data signal lines MUST be treated as RF transmission pathways and laid out accordingly. This is seldom if ever done in audiophile consumer products. But, we do it this way with the Tranquility design. In other words, audiophiles desiring numerous interface inputs as is what is typically seen from other dac products, more often than not, prevents optimal RF layout as the I2S signals must traverse the switching necessary thereby adversely affecting the overall sonic capability of those dacs period. So, less inputs makes RF layout manageable leading to better sound.
We also recognize a multiplexer could be used rather than switching. However, multiplexers are not without their own attended problems. As they too impede layout in their own right.
Another thing to consider when adding interfaces, since they are often in the form of some dedicated interface chip and are likely to require some clocking, i.e. an oscillator, for their operation. Those oscillators give rise to the potential of interfering and intermodulating with the oscillator that is in use for the interface selected. Obviously, this like switching, gives RISE to the potential for jitter and usually does, without exception!
dB Audio Labs selected to use USB because there is no correlation between the clock and the audio data. “Jitter”, as properly defined, requires that there is some sort of clock associated with the data. Absent that, there is NO jitter.
SPDIF includes data correlated with a clock thereby allowing for jitter to occur (not as good).
Firewire does not include data correlated with a clock and thereby does not give potential for the rise in jitter nor does USB (much better).
It should appreciated that both Firewire and USB have more than enough bandwidth necessary for the transfer of digital audio data.
However, there is one major distinction between Firewire and USB that is typically overlooked by audiophiles. That is to say, a dac manufacturer who decides to include a Firewire interface on their dac must provide, or be in the business of providing, developing and/or maintaining a Firewire device driver for EACH operating system, (Windows and MAC) for their digital product. And while some boutique manufacturers many be capable of doing such, there is obviously an intended cost to the consumer. Moreover, there exists the potential for a customer to have, for at least some brief period of time between operating system upgrades, for their dac to become inoperable as their current driver could be incompatible as a new version of their operating system is rolled out.
In contrast, USB dacs typically make use of those drivers found in both the Windows and Mac operating systems. USB specifications and standards require this! So, as long as the dac meets the “USB 1.1 / 2.0 standards”, you are golden. And yes, the Tranquility dac meets these standards!
So, rather than spending our time developing and maintaining Firewire drivers, we’ve selected USB connectivity for inclusion in the Tranquility design and put our efforts into developing the balance of necessary circuitry, e.g optimization of transmission paths, power supplies, dac optimizations, I/V stage, analog output stage, parts selection, etc..
We hope that you consider each and every one of these salient points we’ve outlined when selecting your own personal digital to analog converter. We obviously have, as from the foregoing explanations outlined above.
And that is why you only see a single solitary USB input on the Tranquility DAC ;-)
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Yes, well, there are a gazillion music-computer tools that use firewire, and another gazillion that use usb.
The firewire kind is used by the pros.
The usb kind is used by the folks that shop at radio shack.
The reason, plain and simple, is that firewire piggybacks well while usb does it very poorly; firewire impacts the cpu far less than usb; usb can freeze your computer, firewire can basically never do that.
So why is usb more popular than firewire? Probably because one was promoted by Apple and the other by Microsoft.
I'm simply going to say that of all the serial interfaces, usb is among the most compromised and DEFINITELY not the one you want to use with an instrument that is simultaneously expensive, high-performance and meant to be long lasting.
I don't mean to rain on dbaudiolabs parade, but if there are people out there that are just getting started and wondering what is what, you can do well by simply avoiding usb for anything expensive, high-performance or long-lasting.
IF there was going to be a single input to your dac, it should be coaxial or optical. It should not be firewire for the reasons listed in the post above, although if it were, it might possibly be OK; it should not be usb, at the very least, for the reasons I have given here.
I am under the impression that there are audiophile reasons as well for not relying on usb, such as those in this article,
http://www.stereophile.com/digitalprocessors/cambridge_audio_azur_dacmagic_da_converter/index3.html
which basically states, among other things, that you have to think long and hard about how you are going to connect your computer to that USB cable.
A properly designed DAC (and you can certainly find them for hundreds of dollars less than the one being reviewed above) will not force you to do any such thinking about what your computer is doing on the other side of that optical/coax digital input cable; in fact, it might not even require you to turn on a computer at all. :) |
A lot of competition for less money.♫ |
We understand why some posters could think USB connectivity may not be "audiophile approved". That's why we wrote the VERY thorough technical overview (posted earlier in this thread) for everyone to realize how USB connectivity could actually be a phenomenal sounding choice when it is designed and implemented correctly.
But, there are still some detractors that are skeptical, so here's some more food for thought to ponder and consider - It was recently announced "USB DAC Wins Stereophile's Overall Product of the Year!". Hmm, could Stereophile actually be on to something with their most recent assessments and accolades about USB connected DACs too?
And, from the outset, our inherent mission when we created the Tranquility design was - The true measure of any DAC design and its "inherent technology" comes down to HOW IT SOUNDS as compared the actual master tape!
It is our professional opinion that any given type of DAC solution that has the ability to give audiophiles better space rendition, portray the fragile high frequency harmonic overtones more accurately and subsequently sound more real, should "win the day" as the better DAC. This is how we would like to be "measured" by the audiophile community.
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Steroephile, that's the best you've got to offer as proof USB is better than firewire. You should be able to offer better proof than that, Gordon Rankin and Steve Nugent do.
Personally, I'm trying to make the jump to computer audio. I am intrigued by your DAC, but in reality, how does it differ from the Music Streamer Pro and M2Tech hiface at a fraction of the cost. |
Hi Clio09,
The post about Stereophile's top award to a USB dac was mentioned to demonstrate that we are not alone in our findings about USB's potential and mention the fact that other serious audiophiles have also found that some particular USB connected solutions can sound amazing. BTW: Were you aware that the DAC that Stereophile awarded uses Gordon Rankin's technology?
As far as the "proof" you want, we will stick by our personal mantra ; The superiority of ANY dac design should actually be "measured" by it's end SONIC GREATNESS or lack thereof, period. Anything other sort of analysis-methodology, other than how the product actually sounds, is just conjecture and speculation that holds very little merit for a true music lover. If the DAC design sounds as good or even better than some of the best digital in the world, cost no object designs included, then the "proof" has been met.
Per your question about the Music Streamer Pro and m2Tech hiface, we think that both are great "budget" offerings at their respective price points. Comparatively, the Tranquility DAC was NOT designed as a "budget" offering that was just built with "off the shelf parts" or budget connectors or budget power supplies or with budget level output stages.
In comparison, the Tranquility has MANY proprietary circuit refinements that took years of research and development leading to proprietary optimizations incorporated within. We are proud to say we've found optimizations that no one has ever even considered in any DAC, at any price! Top level passive components, capacitors, custom designed power supplies and regulation, custom discrete output stages along with all of the proprietary optimizations to boot! All of this was done in a quest to create a digital solution that offers a whole new level of sonic greatness.
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Please note the $500 off introductory sale will be ending at the end of this year, Dec 31st. |
dB Labs,
Can you explain how you go from USB input to IIS (I2S) without introducing timing or clock information?
For background, here's the Wikipedia overview of I2S:
"I2S, also known as Inter-IC Sound, Integrated Interchip Sound, or IIS, is an electrical serial bus interface standard used for connecting digital audio devices together. It is most commonly used to carry PCM information between the CD transport and the DAC in a CD player. The I2S bus separates clock and data signals, resulting in a very low jitter connection. Jitter can cause distortion in a digital-to-analog converter. The bus consists of at least three lines:
1. Bit clock line
2. Word clock line (also called word select line or left right clock)
3. And at least one multiplexed data line"
There is both a bit clock and world clock line in the specification. How do you take a USB digital feed, ignore the associated clock info from the computer (which is poorly controlled and introduces jitter if used) and add in the clock info needed for IIS (I2S) going into the DAC?
You act like USB is great since you can just take the data stream and ignore the high jitter in the poor clock signal from the computer. But not so fast. You still need clock info to be associated with the data for the DAC to make sense of it.
How do YOU solve this problem? How is your solution better or comparable to what others have done? |
Hi Cedunlap,
Sure we can explain the I2S area within the dac and USB's inherent timing/jitter advantages.
In a nutshell, USB interconnectivity does NOT carry timing from the computer, it just carries a "start of frame" signal to let the dac know when to start and buffered packets of music data. So, unlike other connection schemes (SPDIF), you do NOT have jitter induced at the transport or through the USB cable (which is a HUGE improvement comparably...when USB is done correctly). Then you are at the receiver portion of the DAC itself where the timing (and potential jitter may happen). A local oscillator approximate to the receiver provides the timing for the dac process. All of the potential timing issues are related to this area alone (when done right). The choice of the oscillator itself, the way that oscillator is configured, optimized, connected and powered will determine how much jitter is then introduced. With EXTREMELY careful optimization it can really good compared to most other digital solutions, especially SPDIF. There has been so much mis-information about SPDIF being "the best connection" as compared to USB that I think it's about time we really sit down and re-analyze how this came to be. It's just not the case. Then again, there's allot of USB dacs done wrong. Could that be why so many think SPDIF was superior?
So, in essence, jitter is never at zero in the entire solution (as you alluded). It is just down to one singular area (which SPDIF can never even hope to emulate comparably). Once this area is extremely optimized the jitter is managed much better than most other digital solutions.
Of course we like to still point out that the actual proof comes from the sound improvement in any connection scheme. Anything other type of analysis other than an actual true improvement in sound quality is just utter speculation, hype and tech-babble! As compared to other digital solutions, the Tranquility DAC captures and conveys the very elusive harmonic cues much closer to an analog solution. There is a naturalness that most digital struggles to convey particularly in the treble region. This is our "proof" as compared to most other digital solutions. The sound improvement itself. |
I'm a little late to the party here, sorry to bump an old thread...but I just gotta. I know this is wordy, complain to my editor.
I had the chance to audition this device through a system I'd heard before with vinyl...and was simply amazed that the sound was coming from a computer's USB. I have never experienced any computer-fed d/a convertor that was worth a long listen, and because of the past experiences didn't even bother with the expensive convertors.
There was almost no reason to throw many thousands of dollars at a device strapped to a dirty pig of a source. Like the days of early Home Theater PCs, there was always some disappointment. My enthusiasm simply didn't exist for standard computer handling of music for high-end listening enjoyment.
My initial reaction was that the sound I heard simply couldn't be coming from the MacMini. Cymbals shimmer through their sustain, overtones and air rendered so well...the sound-stage was remarkable. The liveness or immediacy was tangible...vague terms, I know. Best I can do. The Tranquility DAC seems to make magic previously reserved for product many, many times its price.
It has been over a month since the audition, but I am still stunned and cannot wait until the next time...when I'll bring some recordings I've made live along with a few other items. Some of these are 96/24 rates off an Alesis recorder.
I've known Eric Hider for over ten years, since I calibrated an old Sony RPTV for him. He's been on a continuous path for the perfect hifi, and has never EVER been as excited over any product...not in my memory. Of all the cheap tricks and tweaks he's turned me onto...this unit is the most ground-breaking.
Enough to draw him into this wild and crazy marketplace...in the worst economy we've seen in forever.
I consider him trustworthy to the extreme, ethical, enthusiastic, and honest. He is a friend of mine, but that wouldn't get in the way of an honest review...ever!
I haven't been motivated to get into digital music servers for serious listening until now. Lucky I've been loading my CDs into the laptop iTunes with every play, though, at some near future point that work will be rewarded.
Cheers,
John |
"A properly designed DAC (and you can certainly find them for hundreds of dollars less than the one being reviewed above)..."
If only all of those silly people who have spent a bit of money on digital playback realized that it was possible to get a "properly designed" DAC for only a few hundred dollars! After all, those measure perfectly, right? Actually, wasn't digital sound perfect at the outset? |
In case anyone is interested, it now looks like this Tranquility has won a digital shootout between the Ayre QB-9, the new PS Audio memory player/DAC and a couple other lesser dacs. This comparo was posted over at AC. Here's the link - http://www.audiocircle.com/index.php?topic=75402.100
Tom |
Once I decided to sell my ModWright Transporter and move into using a computer, basically as a source, I had to decide on a PC or Mac. I ended-up chosing a Mac Mini with 4GB of Ram, replaced the standard internal h. drive with a SS Drive and saved all of my music on an external W.D. Fire Wire Drive in .aiff. I then decided to try The Tranquility DAC and the db Audio Labs USB Cable.
DB Audio Labs offers a 30 day trial of the Tranquility DAC and USB Cable for a reasonable restocking fee of $75.00. Once I received the DAC I called Eric Hider, owner of db Audio Labs, and he spent an hour with me optimizing the Mac Mini to ensure maximum musical performance from the system. Talk about great customer service!
I now have approximately 20 hours on the Mac Mini/Tranquility System and I am extremely pleased with the sound. The new system has darker backgroung than did the ModWright Transporter and the music really sounds as if a Turntable were being used as my source. I am very happy and I understand from other owners that the sound will continue to improve as I get more hours on it. I certainly will not be sending the Tranquility back!
I will try to post more details about this system after I achieve 100 hours or so of time on it.
Ken |
I bought a Tranquility DAC a few days ago. Not only was it shipped promptly, but Eric called me today (saturday) and spent over an hour helping me set up my Macbook Pro for optimum playback. I have been playing my system since then and heartily recommends Eric and all the products he sells. He has went over and above what I expected quality customer service to be. Thanks again, Eric. |
Pure music makes a download that you can use with your MAC computer and this seems to be the best way to go. |
