- Joined
- Nov 11, 2004
- Posts
- 2,926
- Likes
- 534
[size=16.0pt]KingRex UC-192 Review[/size]
[size=14.0pt]What is it?[/size]
The KingRex UC-192 is a USBBridge. Made in Taiwan by KingRex Technology Co., the Bridge is externally powered by a wall wart power supply and includes a 5 foot USB 2.0 hi-speed USB cable. Input to the bridge is via USB with SPDIF output via coax and AES/EBU using the new Mini-XLR connector and I2S output via Ethernet connector. Included in the Spartan packaging is a mini cd with instructions and drivers for Windows, along with the aforementioned items. No drivers are required for Mac. A Warranty card fills out the included items offering coverage for 1 year and exchange for a new product in the first month. Shipping back to KingRex is responsibility of the user with return shipping back covered by KingRex. Pricing is set at a very reasonable $189.
[size=14.0pt]What do it does?[/size]
Using a grammatically backwards phrase coined by my boy when he was young, lets see what, exactly, the KingRex UC -192 does. The UC-192 plugs into the USB 2.0 port of the computer and converts the USB signal to SDIF and outputs via RCA coax out or AES/EBU. Or it converts to I2S. The latter is a rare input on today’s and yesterday’s dacs. The Northstar, PS Audio, and Wyred 4 Sound dacs have this input on some of their models. I am sure there are more Dacs with it and not sure of how the connection is done. Ethernet’s RJ45 connector is just one way of connecting I2S. As for a coax SPDIF, pretty much every dac made has one of these connections. Yes there are exceptions but it is the most common interface for Dacs. And the AES/EBU format is also included and found on many dacs, especially in the pro area. Though with the UC-192’s mini XLR output, you’ll need to find a cable with that and a regular XLR to make the connection to most AES/EBU ports.
KingRex does not mention what chip is used to run the code required to translate the USB stream to the outputs, but we do know that it is using the Adaptive isochronous method of controlling the bit stream. This means the Computer is controlling the timing of the stream to the USB device using its master clock. Typically the USB device must derive the master clock via some sort of frequency synthesis but the specs for the UC-192 indicate the inclusion of a high quality 12 MHz clock on board. Perhaps this clock helps to keep jitter lower than would otherwise be possible by synthesizing the clock for the USB bus. All of this is important because while all the bits are coming over the USB bus in bit perfect fashion, the timing is critical to ensure low jitter. In computer audio small variations in timing cause jitter which, depending on how much and where it manifests itself in the audio band can cause the resulting musical experience to be: noisy, bright, hazy, not in focus, or any number of audio adjectives we use to describe when something just does not sound perfect. The adaptive method of implementing USB to Spdif conversion is used by lots of manufacturers in many different formats and price ranges, from the simple $25 converters limited to 44khz and 48khz/16 bit to $1200 96khz/ 24 bit. Many Dac manufacturers also use this methodology to connect via USB to your computer.
Asynchronous is the other method used by a smaller but growing number of manufacturers where the master clock is not the computer but is actually on the USB device. This control of the stream allows for more precise timing and hence lower potential jitter and its promised advantages. In theory, the jitter can be made lower via this method but you will get all sorts of opinion on which sounds better. In fact, Dave Clark of Positive Feedback Online came out with his pronouncement of a preference for the adaptive methodologies over asynchronous to his ears in a recent overview comparison of bridges.
Now that we have the somewhat technical stuff out of the way let’s move on to the rest of what it does. The UC-192 is a big leap forward in USB / Spdif Converters. We have been limited to 96 kHz and below for most converters anywhere near this price for some time. Now KingRex gives us the ability to stream native files up to 192 KHz and 32 bit resolution. Even though there is not a lot of music being offered at above 96 kHz, there is a need for getting hi-rez data to your hi-rez capable dac. More on that below.
[size=14.0pt]Why do I need it?[/size]
Computer Audio is great but getting the bits from the storage media to the music player and out to your audio system have been a challenge for many. Many computers do not have spdif outputs to go to an external dac. Sound cards for desktops that do offer spdif outputs live in a noisy environment and the dacs on those cards along with the confusing pro audio type software keeps a lot of us from experiencing what great sound is possible from computer audio. Toslink connections from many computers do a good job of filtering the chassis noise of a computer but some do not allow 88 kHz or files above 96 kHz files to pass. USB has become ubiquitous and most computers made in the last few years have the ports meeting the USB 2.0 specs, so hi-rez is possible. From DVD-A rips to upsampling, you now can get good hi rez to your dac for a reasonable price. And even if you just want to hear the standard 44 kHz rips from your cds, the UC-192 will do the job.
[size=14.0pt]The Test System[/size]
Running Springs Haley- power conditioning for the Mac, dac, UC-192, and Amp
DIY power conditioner- power conditioning for the external disk drive
Apple Macbook – 4GB Memory dedicated to playing music
External Disk Drive- 1TB disk connected via Firewire 400 to the Mac
Blue Circle BC-509 – 192 kHz – 24 bit capable dac
Bel Canto EVO4- four channel amp run in bridged stereo mode
SP Technologies Timepiece 2.0 Monitors- speakers
Blue Circle Hat Peed Thingy- Headphone amp with standard outboard power supply
Shure SRH 840 –headphones
Element Cable Titan- XLR cables from dac direct to amp
VH Audio Pulsar- SE interconnects to feed the headphone amp from dac
Copper Flat Cable- Proprietary speaker cables not too dissimilar to Goertz M series
Halide Design Bridge- Async USB to spdif bridge used for comparison
Empirical Designs Coax- Coax cable to connect UC-192 to dac
Wireworld UltraViolet USB cable – used to compare to supplied KingRex USB cable
Test Music
All files are AIFF and range from 44khz to 192khz stored on the external drive, played via Pure Music with memory play and hog mode.
Music
Future Sound of London
Diana Krall
Neil Finn
Arvo Part
Neil Young
Suzanne Vega
Pink Floyd
Andreas Vollenweider
Keith Jarrett
Alison Kraus
Jazz At the Pawnshop
Nils Lofgren
Weather Report
Disclosures
I guess it is best to disclose here that I have no relationship with KingRex other than that I reached out to them to ask for a demo unit to review for Head-Fi. I expect to send it back to them after this review. I also want to point out that this entire post is copyrighted and should not be re-posted anywhere without my permission.
[size=14.0pt]UC-192 Setup[/size]
I use an Apple Macbook for my main system. I use PC in my home office but did not test the UC-192 with the PC. For the Mac, there are no drivers to load or setup. BUT and this is a big but, you must be running OS-X, 10.6.X ( or Snow Leopard) as your operating system if using SPDIF. When I first started to use the bridge I had Leopard on my system. The UC-192 does not work with it. I emailed Christine at KingRex and she had me ship it back to upgrade the firmware and did confirm that it only works with Snow Leopard when you use Spdif. Apparently it does work with older OS with I2S. When the unit came back it was simple plug and play. Pure Music recognized it immediately and gave me the option to select Spdif out as my setting and 192 as my target rate. PM plays all rates natively without need to switch anything. Although when I tried some 88khz files they would not play properly with this setting. I did fix the issue by adjusting the target rate to 176 and then the 88khz files played perfectly. I just made KingRex aware of this and await any feedback on what may be wrong in my setup (I do have power of two set on upsampling but in this case the files were being played natively). All 192 kHz files played fine natively when PM is set for a target of 192. Also any upsampled 96khz files also played fine at 192khz with the UC-192.
[size=14.0pt]Listening[/size]
I have been a big proponent of Toslink for many years. I like the way it isolates noise from a computer environment from getting into the dac. And I am a big proponent of getting the best Toslink you can. I like the glass based ones from Wireworld and Silflex. They are leaps and bounds better than the eBay glass specials and way better than all the plastic toslink cables I have tried. Bass is tighter, definition is better, and way more open.
I am also a big proponent of trying different music players. While I have not tried all of them available for Macs, I am really pleased with Pure Music. In my system it sounds lots better than itunes and makes hearing differences between components and tweaks easier.
Toslink
I used my Silflex Toslink as my base line for the listening tests and used the speakers to get a good feel for the resulting sound quality prior to listening to the UC-192 with headphones. Very good Toslink sounds clean with good definition, instrument placement and depth. It is very quiet and does show the benefit of many tweaks. It has a fairly broad soundstage with good solid bass. The bass area is one where Toslink is the weakest in my opinion. It can sound a bit fat on some recordings although it fills the room nicely. Also decay of reverb, hall ambiance and other cues for depth are reproduced well but not nearly as well as the UC-192.
On my Mac, Toslink has a few limitations. First it cannot play 88khz files and second it cannot play higher than 96khz. It also seems to have some phase issues when playing 44khz or 48khz files with Pure Music’s excellent upsampler.
UC-192
The UC-192 strikes you at first with the width of the soundstage. Really wide is what I first noticed. Weather Reports Tale Spinning Remaster has a song titled Badia which is great for testing space and detail. The UC-192 gives the opening stringed instrument a solid placement way on the right. Detail was very good as was all the reverb trails and placement of the instruments. It was much tighter and more defined than toslink on the bass lines and drums.
The UC-192 rendered Diana Kralls Live in Paris Cd very nicely. Her piano was not overly rich as it was in comparison with toslink. I never realized how toslink was romanticizing the sound a bit. And bass again was tighter and gives a better definition of the hall ambience. Her voice was more focused than with Toslink with a bit more detail. Voice reproduction was also very good on Alison Krauss and Suzanne Vega cuts. Alison’s voice can sound a bit breathy or slightly bright on some systems and with some front ends, but it sounded great with the UC-192.
The UC-192 did really well with space and dynamics. Andreas Vollenweider’s CDs are recorded really well and Caverna Magica is a great test of depth and nuance. The drops into the water are captured very well with better detail than toslink and with images more defined. His White Winds Cd has a cut called Glass Hall that is also very good for checking high frequencies and overtones. The wind blowing through the glass chimes was believable and offered a good illusion of movement of the wind.
Where the Uc-192 really showed how much better it could be was on sorting out complex material. Keith Jarrett’s Köln Concert in 24 bit 96khz was much easier to follow as compared to Toslink. The piano opened up and overtones were clean and clear as opposed to slightly muted. Also with Arvo Part’s Credo cut from the Collage CD, the chorale pieces were so much easier to understand compared to Toslink. Enunciation, breath, and individuality all stood out with the UC-192. And dynamics and instrument detail also were more resolved with the UC-192.
With Pink Floyd’s Echoes CD comparing the UC-192 to toslink you could hear how much cleaner the drums were. You got a good sense of a wall of sound with the UC-192 and with good depth.
When the UC-192 was allowed to reproduce upsampled 44khz music it did really well. I did not have the phase issues that I had with Toslink when going up from 44 to 88. And even at 176khz some not so smooth recordings sounded quite nice. I am still a native type guy preferring it to upsampled but I may have to experiment more with it in the future.
I don’t have many files that are native 192khz. But I do have a good collection of Neil Young archives with live sessions. Man, talk about open, smooth, clean, WOW. If this is what we can expect from the future, then sign me up. Neil’s Old Man from the Massey Hall recording was really nice. Plenty of detail and as natural sounding as you could expect. Some files like Fleetwood Mac’s DVD-A remaster of Rumours sounded like someone went nuts on the EQ. Nasty out of proportion highs that made me want to turn it off. It was not the UC-192s fault as the files sounded just as nasty with the HalideBridge.
After I listened to the UC-192 with its shielded USB 2.0 cable I naturally had to try a more expensive USB cable to see if I could wring even more out of the UC-192. Sadly to say after repeated tests with the Wireworld UltraViolet USB cable I came to the conclusion that I preferred the stock cable. I don’t know if the ferrite on the end of the stock cable was doing it or what but it just sounded quieter and smoother. The Wireworld lit up some recordings and made them a bit more detailed but at the expense of some noise. My notes consistently mentioned “seems quieter” and “better depth” for the stock cable and metallic and leaner with the Wireworld. So there is no need to spend another $100 on aftermarket USB unless you want to try some others. The stock cable is a good match for the device.
Step UP Comparisons
Naturally, or maybe not, one might want to know how the UC-192 stacks up against a bridge that is more than twice the price. In almost all cases the Halide Designs Bridge did perform better in terms of space, localization, bass definition, and high frequency naturalness. With a price tag of $450 it should. The UC-192 had better width and immediacy and by that I mean it sounded a bit more close, like row 5 versus row 20. The UC-192 also threw a much better “wall of sound” for rock music; my notes on some Pink Floyd cuts noted that the Halide sounded kind of reserved in comparison. And the differences get very small with headphones as you will read a bit further down. And remember the Halide Designs Bridge only goes to 96khz.
[size=14.0pt]Headphones[/size]
My Shure SRH 840s are not the last word in headphones. They don’t open up like some more pricey cans, have a somewhat warm bass, and are not the last word in comfort. That being said, I like them better than my Senn 650s, Senn 800s, AKG 601s and countless others. Why? Because the get the mids right. No, they are not perfect there either, but they balance good mids with respectable bass and fairly decent highs. They are not super detailed but give you a good idea of what is in the recording. My amp is new to me, but so far I am liking it. Another Headfier’s excellent sounding Matrix (Sun or Earth chips preferred) gave me the push to get a good amp and the Blue Circle Hat Peed Thingee is very nice. I used to like my Benchmark’s HP out but this is even better. And I can’t wait to compare it directly with my friends Matrix.
The first thing I noticed when putting the UC-192 through its paces with Toslink and the Halide is that when listening to headphones you don’t get anywhere near the depth layering that you do with a good speaker system. Reverb trails, decay and hall ambience are there, just not in front of you. It is kind of like pushed to the side. Just the nature of the beast. And here the comparisons about depth and space with the Halide become much much smaller. Localizations and tonal differences still exist but the overall difference is less between the Halide and the UC-192.
On all cuts we are much closer to the music with the soundstage still nice and wide but a bit compressed when compared to a speaker system. Diana Krall’s voice is right in front of you, as is her piano and the audience coughs. It is a bit better with the Halide but still not as deep as when listening through speakers. Noise is also not an issue with the UC-192 when using headphones, though I am not a very loud listener.
I do not have the luxury of having lots of cans around to try with the UC-192. Aside from some very slight differences in tone in the upper highs and bass as described above in comparison to the Halide, the UC-192 is a very neutral piece of equipment with excellent dynamics.
[size=14.0pt]Final Words[/size]
The UC-192 is an excellent device that is quiet, dynamic and performs as expected. It has a naturalness and versatility that make Toslink obsolete for me. That is saying a lot. I have heard many USB devices including some low cost bridges that anemic and bright. And I have heard quite a few dacs that take away dynamics or add a noise floor to the system when tested with there USB sections. The UC-192 does not do that. For under $200 I would take this bridge and pair with a nice dac that did 192 before I would buy any sub $1000 USB dac. If you are looking for a solution to get great sound from your computer while future proofing for a good while, you need to check out the KingRex UC-192.
