Mark02131 - your logic on Toslink would seem to make sense, but it is flawed. The only benefit is galvanic isolation, and you can get this with coax also.
The optical-electrical conversions add a LOT of jitter to the digital signal that is carried to the ASRC chip. It is my least favorite means for digital transmission. Fine for data, but not for real-time timing-sensitive signals.
Steve N. |
Thomasedison - I would keep the DAC-1 or DAC-1 USB in calibrated mode, and change the balanced output jumpers to max output level.
I replace the fuses with 3 amp fast blo. This is sufficient to protect the transformer and board, but maybe not the chips on the board. Chips are cheap, but transformers and boards are more expensive. This does seem to make a difference. You can also try the silver fuses in fast-blo.
A good power cord also makes a world of difference. I have one custom-made for my Spoiler DAC and I use this one on my DAC-1's. It is over $1K and silver though.
Steve N. |
Mhfun -
1) because the jitter is not almost nothing IME. I mod the DAC-1 and DAC-1 USB, so I get to hear them both frequently on my reference system. (The DAC-1 USB is a significant improvement over the DAC-1 IMO, particularly the USB input) I can plainly hear these differences. The only explanation that I have is their system must not be very resolving or other sibilance is masking the jitter if they cannot hear the difference. There are other things that they say they cannot hear, so I believe this is a reasonable explanation. I have found that even many famous magazine reviewers systems are sub-par, so this is not unexpected.
2) The Pace-Car is only similar in function to only one other reclocker, and that is the Genesis Digital Lens. This one also stores the data in a FIFO memory and clocks it out with a totally isolated, independent clock. The difference is that the Genesis is designed to work only with CD's of a limited length. The memory in it will eventually overflow, so it cannot be used with computer and long playlists for instance. The Pace-Car does not overflow.
The other reclockers that you mention are primarily ASRC, or asynchronous sample rate converters, similar to what is done in the DAC-1, Bel Canto and others. They change the data stream using various chips that upsample the data to a higher resolution. This asynchronous process does reduce jitter significantly depending on the chip used, but I have yet to encounter a chip that has complete immunity to the incoming jitter. Also, the quality of the clock used to drive the ASRC chip is critical. A $2 oscillator is not sufficient to get inaudible levels of jitter. A Superclock, Tent clock etc.. is required IMO.
The other way that other reclockers work is to use multiple levels of PLL or phase-locked-loops. Each PLL locks onto the incoming stream and reduces jitter a little. After passing through several of these, the jitter can be reduced significantly, but there is always some sensitivity to incoming jitter. The clock quality again is very important too, this time of every stage. If there are 4 PLL's, then you need 4 Superclock4's for instance. This can get really expensive.
Another difference with the Pace-Car is that is also has I2S output. If you have a DAC that can accept this interface (DAC-1 can be modified), this is a more direct route to the D/A chip and reduces jitter even more compared to the typical S/PDIF input.
Steve N.
Empirical Audio |
Audioengr - I also stream my music via PC iTunes to an Airport Express, toslinked into my Benchmark DAC-1.
1) May I ask what is the reason to use Pace-Car reclocker while Benchmark DAC1 already has UltraLock that claim to reduce jitter to almost nothing?
2) How is your Pace-Car compare to other reclocker devices such as Audio Alchemy DTI, Meridian 518 or Monarchy DIP 24/96? |
Thanks, Mark. I already own the coax cable, so I'll try that first.
Steve, would you keep the Benchmark's volume in 'calibrated' or 'variable' mode?
Would replacing the stock fuses make a difference? |
I would use XLR first any maybe compare to see what sounds best.
Jax2,
I agree the more steps along the path the more chances to signal derogation. I think light pipe is less suspetable to problems than electrical signals and can cary 8 channels of 24/96 audio, thats a lot of room if you are only using it for 2. one way you convert digital to electrical signals the other to light. We always use fiber in high end computers to large disk arrays because it a better, faster medium than electrical signals.
|
Thanks for all of your advice, guys. I have decided to get a Trends UD-10.1 USB converter for now. I will use my iBook laptop attached to an external hard drive. I will go
Mac iBook >Trends USB converter > S/PDIF cable > Benchmark DAC-1 > analog out > Musical Fidelity A5 Integrated > speakers.
Down the road I will either mod my existing Benchmark DAC or upgrade to a USB DAC, but for now this looks like the best way to improve my sound greatly for just $150.
The only question I still have is what cable format to from USB converter to Benchmark DAC. I can use my existing Stereovox HDXV S/PDIF to BNC cable
or
I could use an XLR cable between the two.
Any feedback on that? |
Toslink is a digital interface and is not audio it is pure digital read off the disk converted to "light pipe" and shipped out, thats it, only data ready to be read by a down stream device. I did not say it was an audio signal, did I? I'm not sure what you're trying to say. The signal has to carry timing and content, and you are converting it from one language to another, and then back to yet another when it reaches the DAC. I don't know that much about this stuff, but my experiences suggest to me that every stage of the road from one point to the next may effect the outcome, and that it's best to do as few conversions as possible. Are you suggesting that because it is not an audio signal that it is not vulnerable to any degradation/errors in transport and conversions? Marco |
Hey Jax2,
Toslink is a digital interface and is not audio it is pure digital read off the disk converted to "light pipe" and shipped out, thats it, only data ready to be read by a down stream device.
Mark |
Juanitox - you dont have to trust me, although I wish you would.
I rely mostly on posts on the forums - customer feedbacks for advertising. I sell all of my products word-of-mouth. No advertising to speak-of. My advertising budget for the year is about $250. Even with this, I have had a 5 month backlog all year.
I post on these forums mostly to dispell misinformation and prevent people from making bad choices.
Steve N.
Empirical Audio |
agree with KANA , this french flying saucer based on the airport express is the best source i ever own (includes audio aero, wadia, dcs stuff..)
it sounds simply like a very good vinyl player..
and don't trust guys like Steve who are just here to sell their products in every post about pc audio , here and on audio asylum. not a very honest point of view.. |
If you can swing the coin, I'd go with one of Steve's routes over the simple converters. A good friend whose ears I respect heard a demo of the PaceCar at a show and was very impressed. If you have to go with a less expensive option for now, most definitely do not use the Airport express if you want decent sound for sitting down and listening. I've tried to make the AE sound good with several different DACs, but alas, you are limited by the unit itself and the conversion circuitry within the unit that gives you the S/PDIF (toslink mini) assuming you're going for the best sound from the stock unit. I have never been able to get sound I wanted to sit down and listen to from the AE (stock) - if it's background music you are after, it's as good a solution as any and you probably don't have to spend any more. In any case, if you are looking for the best sound from a $200 investment in what you already have go with a decent converter and your Benchmark. Just my opinion.
Marco |
TomEdison - the Modded DAC-1 would probably be more smooth and listenable IMO.
Most unmodded gear has sibilance as well as jitter. Eliminating the sibilance is probably more important than reducing the jitter. However, both are needed to achieve a really fatigue-free sound with the best clarity.
BTW, nice invention, the lightbulb, but they are quickly becoming relics.
Steve N.
Empirical Audio |
Steve,
Which would give me better sound:
PC>Airport Express>Pace-Car>unmodded Benchmark DAC-1
or
PC>USB>supermodded Benchmark DAC-1(w/ additional mod to add USB)?
Anybody:
Since either of the above would be done 'down the road', what would be better for now:
PC > $150 USB/Toslink Converter > Benchmark
or
PC > Airport Express > Benchmark?
Any Recommendations for a $100-$200 USB/Toslink Converter? |
Kana13 - you've got to be joking right?
This will never compete with a Pace-Car. I dont care how good the clock is. I also do a mod to the AE called the Off-Ramp Wi-Fi. Same thing as the French company, new clock, new power supply, new S/PDIF output circuit. It's not even remotely close to what the Pace-Car does. I have only sold a few of these. I dont even try to sell them anymore. Pace-Cars is what sells because they are amazing.
Steve N. |
Marco and Jax2: I know the Mac platform is solid for USB out. I have an old Mac iBook I could use for that config, or I could buy Windows Vista and stick with my PC. I want to stick with iTunes. I've read that Foobar and ASIO are too much of a headache. Would iTunes for PC w/ Vista equal iTunes on a Mac for USB out? Marco and Jax2 are one and the same. I know, it seems magical, but they're both just me. I did not mean to imply in any way that the Mac platform was inadequate. I use Macs exclusively for over ten years now. I only meant I would use the USB rather than the internal toslink option given the choice. As far as an inexpensive converter for your Benchmark, if you can find a used Waveterminal U24 that'd be a nice option...My friends Edirol seems to do a decent job...I think it's a UA25. As far as the two platforms, I just know Mac works: OSX hasn't given me any major headaches, is almost impervious to viruses, worms and other evil attachments, works brilliantly in all the graphics software I rely upon for my work, and streams music just fine with nary a hiccup.It has a very instinctual interface, which seems to get better all the time. I've used an iBook and that works perfectly well for streaming music, as I'm sure a MacMini would. Either way, if you plan on using the new Mac operating system, Leopard (10.5.X), make sure you have at least a gig of RAM in whatever box you choose, and that your hard disk is a large one (the newer MacMinis are a bit more versatile in that regard I guess - someone correct me if I'm wrong there). Like Vista, or so I'm told (I steer clear of PC's if I have a choice), Leopard is a memory hog requiring 512mb of RAM just to run the OS. OSX also runs smoother and faster if you leave about a third of the boot disk free (hence larger drives are better for Leopard). Marco |
If you want to transform the AE into something world-class, then try this
http://www.db-system.ms/frame-airport.html |
Thanks for all of your responses so far.
Audoiengr: Thanks Steve, for answering my first question. It's good to know that iTunes Windows XP to Airport Express is the same quality (however low) as Mac iTunes to Airport Express.
The Pace-Car at $1400 is pretty steep for me at this time. If I were to eventually invest that much, how would that compare with getting my Benchmark modded to accept USB?
Right now I'm interested in a $200 upgrade. I could get a Trends Audio or equivalent USB/digital converter and go
PC > Converter > Benchmark
Marco and Jax2: I know the Mac platform is solid for USB out. I have an old Mac iBook I could use for that config, or I could buy Windows Vista and stick with my PC. I want to stick with iTunes. I've read that Foobar and ASIO are too much of a headache. Would iTunes for PC w/ Vista equal iTunes on a Mac for USB out?
And would a $200 USB/Toslink converter be better than sticking with wireless to Airport Express. Either one would end up in my unmodded Benchmark DAC-1
Can the Mac Mini be used instead of an Airport express for wireless use? If so, is there any advantage to sound quality over an iBook wireless to AE? |
Folks, it's Mac, not MAC. A shortened form of Macintosh, not an acronym. MAC is something else (Media Access Control, as used in the term MAC address). |
The data stream from the AE is identical whether it is PC or MAC. The audio quality is the problem - very jittery. You can get decent "background music" with a glass Toslink, but that's all IMO. If you want to transform the AE into something world-class, then I recommend this:
http://www.empiricalaudio.com/frPace-Car.html
Steve N.
Empirical Audio
Manufacturer |
The MAC mini has an optical output that is fantastic and plugged into a good DAC is all you need. Personally, I would not allow the S/PDIF conversion to be done inside a computer. If you use the Toslink on the MacMini or their towers or laptops then the conversion is being done in noisy electronic environment of the computer. I would bet you'd get an audible improvement by taking that conversion outside of the computer, as it would be with a USB DAC, USB Converter, or better still, a device like Empirical offers that goes direct to I2S which is the native language of the DAC chip. Marco |
I find that the MAC is just all around better when it comes to dishing out the music. The MAC mini has an optical output that is fantastic and plugged into a good DAC is all you need. Also the Transporter is a nice solution.
I tried using a PC/XP with an M-Audio audiophile192 card using s/pif out to my MDA1000 but it sound was dull and did not sound right. I have never heard a PC sound really really good and I don't know why I really wonder about the Microsoft O/S and drivers.
|
Do yourself a big favor and take the Airport Express out of the equation. Yes, either get a USB converter, or get a USB DAC (which essentially puts the converter in the box). I've tried getting good sound from an AE but could not (flat, narrow soundstage, and not very engaging). I did not like the HagUSB device I tried out. I liked the Waveterminal U24 very much, but their not available anymore. Check out the offerings at Empirical Audio. He also does some mods to the Benchmark that may interest you. Love your light bulb idea...and the movie projector thing, well you rock dude! Keep up the great work! Marco |
