Article: Arcam rDAC Asynchronous USB DAC Review

[Oystein]

@Schneider:<br />

<br />

You might wanna look here:<br />

http://www.computeraudiophile.com/content/ordered-Lindemann-USB-DAC-24192<br />

<br />

Some practical information which might be helpfull ...

[Audio_ELF]

Have you seen this thread... http://www.computeraudiophile.com/content/List-USB-Devices-Compatible-Linux<br />

<br />

According to Sonore's list the rDAC works with Linux on x86 hardware. <br />

<br />

Eloise

[Schneider]

Thank you for the links.<br />

<br />

<cite>Concerning the problem running the DAC from you ARM system; have you considered that the system just might be too slow to feed DAC through asynchronous USB? I would imagine that Seagate has equipped that Dockstar with a fairly slow CPU, and dedicated chips are taking care of all the high speed transferring of data. And as ALSA is running on the CPU, it might just be too slow to keep up with it.<br />

Have you tried playing some WAVE files at a lower sample rate/bit rate, to see if it can keep up with, for example, 8 kHz/8 bit WAVE? If it can, it would point towards a bottleneck in the system, rather than a bug.<br />

Or have you managed to play audio fine over the USB port from the Dockstar with other, non-asynchronous DACs? It *could* just be the Linux implementation of asynchronous USB audio syncing that's implemented in a way that is too slow to work on low end ARM CPUs. Have you tried loggin in to the device via SSH. </cite><br />

<br />

The Dockstar is powerfull enough to play FLAC files and takes only 4% of the processor time <br />

With HRT II+ async DAC, it should go well if the firmware >= v1.5. I've tried with a v1.4 firmware model: everything went good except the DAC energy consumption via USB (a known bug with this firmware).<br />

<br />

As I said, the Arcam rDac plays without any trouble on x86 Linux.

[runeks]

Cool. Good to hear. If it works with other async DACs it certainly isn't the async USB implementation that is the problem. It would be interesting to know what is causing this though, since - as far as I know - the two DACs (rDAC and HRT II+) use the same async USB chip.<br />

<br />

The HRT Music Streamer II+ actually seems to be exactly what I'm looking for. Async USB to analog, nothing else.<br />

I must admit that I have a hard time seeing what justifies the $350 price tag, though. It looks like a very simple design, based on the pictures you've posted. Perhaps the async USB chip licensing fee is what keeps the price up there?<br />

<br />

<i><b>EDIT:</b> It turns out they developed the code for the USB chip themselves, so it's not licensed. From this article:<br />

http://www.6moons.com/audioreviews/hrt2/pro.html<br />

<br />

On further thought I guess it's a little too simplistic to expect a DAC's price to be proportional to the cost of the components it contains. It makes sense that the vast majority of the cost is from developing the actual design, and not realizing this design as an actual PCB.<br />

<br />

I read that Gordon Rankin spent several months developing the async code for the TAS1020B chip, so it makes sense that all this development effort would increase the price of the product.<br />

<br />

Still, I would really appreciate an in depth explanation of all the hurdles one must overcome to develop a good sounding USB DAC. It would be very interesting to hear, plus I might be able to convince myself to spend $350 on it then .<br />

<br />

One thing I'm interested in specifically is that a lot of other manufacturers of DACs stress the importance of a clean power source to produce clean audio. As far as I've understand the power source is used to drive the clock, and the more clean the power is the more precise the clock will be. But these HRT DACs all use the USB 5V line, which by many is said to be very noisy because it comes from the PC with all its many many components.</i>

[pitman]

Hi Chris,<br />

<br />

Does your assessment of the Arcam still hold up, or are there newer players of comparable price that are superior?<br />

<br />

Also, have you done any comparisons between the Arcam (or any USB DAC) playing lossless files, and a comparably priced CD player? I've been a fan of NAD, and wouldn't want to make the change unless I thought something like the Arcam were at least as good as the (lower end) NAD 515BEE.<br />

[david]

Hi Chris,<br />

<br />

I found your great site after watching your interview on Twit.tv a couple of weeks ago which I enjoyed.<br />

<br />

I was wondering if you or one of your readers could point me in the right direction with regards to connecting an Apple TV2 to an Arcam rDac.<br />

<br />

I was reading your rDac review where you say the optical S/PDIF Toslink input on the rDac isn't a patch on the USB or coaxial S/PDIF input.<br />

<br />

My Apple TV2 outputs via S/PDIF Toslink as does the Panasonic Plasma it connects to via HDMI. Is it is possible to use some sort of conversion so that I could take advantage of the USB input on the rDac?<br />

<br />

I am using an Arcam Solo Mini with Arcam Muso speakers. I have converted hundreds of CD's to Apple Lossless over the past few months and I really like the Apple TV interface, but I would like to get the sound back to the same quality as playing the CD's in the Arcam.<br />

<br />

Looking forward to any advice you can offer. David

[Elberoth]

There is a review of TeddyPardo rDAC PSU - a high quality, linear aftermarket power supply for the Arcam rDAC owners - posted on HighFidelity web site:<br />

<br />

http://www.highfidelity.pl/@main-199&lang=en<br />

<br />

I have tried it in my office system, and it indeed takes the rDAC to another level, where it can compete with units costing $1000-$1500 with ease.<br />

<br />

A great product, worth every penny.

[philwright]

I've had an rDac for 6 months or so and think it's an audiophile bargain - better than the Meridian DAC I was using. More than able to hold its own in my Mac Mini / Ayre / Harbeth system. <br />

<br />

I heard elsewhere on the web about the VN10L linear power supply from Maplins (Radio Shack of the UK). At £19 I bought it on the basis that if it didn't help I hadn't lost anything. Bit fiddly to set up - it's variable voltage so make sure you set it to the required 6V. And it doesn't play to any of our audiophile sensibilities - it's basically a big heavy brick. <br />

<br />

But it does make quite a difference to the sound quality, in line with what people say power supply upgrades do. Even better value than the rDac itself, and that's saying something. It would be interesting to compare it to the Teddy Pardo's and their ilk; my guess is they would sound a bit better. But at 10-15 times the price they should (and I was considering one, so am not saying they are silly prices). <br />

<br />

I'm sure you could find something similar in the States, most probably from Radio Shack. Bottom line is that it's a no-brainer upgrade.<br />

<br />

http://www.maplin.co.uk/ac-dc-multi-voltage-20w-power-supply-32754

[tokapaho]

Hi Chris,<br />

Excellent review, to bad the WiFi option weren't possible.<br />

However; I'm considering a purchase of the Arcam rDAC, but choice of input is something to be decided so my question is; would the rDAC benefit to be used with the Halide Design's The Bridge, or would this just be overkill? I'm fairly new to all of this and I'm struggling to find all the info needed for my set-up.<br />

<br />

Anyone?<br />

<br />

Regards,<br />

<br />

<br />

<br />

[dummy]

Way overkill. The Halide does the exact same thing as the USB input of the rDac. Asynch USB up to 96khz. Halide is Wavelenght's Streamlenght asynch and rDac is dCS asynch. Both implementation are excellent (given their credentials, haven't heard the Halide).<br />

<br />

Beside, the Halide won't go beyond 96khz where the coaxial SPDIF on the rDac goes up to 192khz. One option would perhaps be the Musical Fidelity V-Link but, again, It doesn't go beyond 96khz either so you won't benefit from the rDac coaxial full potential. But the V-Link is 199$ vs Halide's 450$.<br />

<br />

You may want to consider other pricier USB DAC's options if you're willing to spent 950$ for the rDac+Halide. <br />

<br />

Just my .02 cents...<br />

<br />

[Elberoth]

Halide + rDAC doesn't make any sense (I own both). Even if in theory Halide solution would be better (and I do not think it is) the very fact that you have to use SPDIF interface on top of it, would take away any performance advantage.<br />

<br />

Use the rDAC inbuild USB input which is as good as it gets or move to a higher quality DAC (or get a TP PSU with the rDAC).<br />

<br />

[Audio_ELF]

The only "upgrade" which makes sence with the rDAC is a PSU such as Teddy Pardo. You *may* also benefit from a dedicated USB card such as the SotM that Chris used in his C.A.P.S. V.2 server. <br />

<br />

Eloise

[The Computer Audiophile]

Wow I sense a bit of harmony and agreement on the rDAC options. Is the Earth spinning the opposite direction? Only kidding. I agree with the answers above.<br />

<br />

[david]

So... I understand I have no way to connect by USB.<br />

<br />

I will look at the Power Supplies available. Thanks for the ideas.<br />

<br />

Given that in the rDac review Chris was not impressed with the Optical Input is it worth buying one of the boxes that converts an Optical cable to a Coaxial cable? <br />

<br />

If that would work can any of you tell me whether my preferred option of connecting the Plasma TV by Optical to the rDac Coax /or/Optical is as good for Apple TV music quality, as having 2 cables going to the rDac; 1 from the Apple Tv and 1 from the TV.<br />

<br />

I know the others using the system would find it much easier to only have to select TV on the Arcam regardless of whether watching TV or the Apple TV.<br />

<br />

I am new to this, but I am guessing that I want the least jitter and clock miss-timing (if that is the correct term) and I don't know if a TV is much worse than an Apple TV.<br />

<br />

Out of interest does the fact that an Apple TV or any streamer is connected by an ethernet cable to a switch, then a router and then to the computer completely remove it from the problems associated with the noisy (if that is the right term) computer environment?<br />

<br />

Thanks Again, David

[Elberoth]

And another review of the Teddy Pardo rDAC PSU, this time from Audio Video:<br />

<br />

"It was a coincidence, that an audiophile I know, a person well known in the audiophile world, borrowed me his private power supply made by Teddy Pardo, who specializes in making PSUs for Naim devices. We are talking about a power supply dedicated to the rDAC. It costs 232 euro and is sold directly by the manufacturer himself (www.teddypardo.com). This is a line power supply, with solid stabilizing circuitry, using proprietary solutions conceived by its creator.<br />

<br />

So the question is: does it improve the sound of the DAC – and if yes, by how much?<br />

<br />

In a word - drastically. So much, that return to the standard PSU is simply impossible. The Teddy Pardo power supply changes everything. The sound gets pace, drive, the stage gets bigger, its planes are better differentiated – the timbres are no more pastel, but clear and juicy. We deal with a ‘de-facto’ new device, which has to be assessed from a completely new perspective.<br />

<br />

I used the Audiolab 8200CD and Marantz NA7004 for comparison – two very good players, each costing about 900 euro. And both were beaten by the rDAC – Marantz completely, and the Audiolab – well, actually also. The described combination (rDAC + Teddy Pardo PSU) creates a very lively, yet natural sound, which – in context of its price (about 650 euro !) – reproduces timbres and sound stage brilliantly. I was enchanted by the quality of the mid and upper ranges. The string section from “Watermusic” - Handel (HMX2907010) – was characterized with unexpected resolution and fine reverbs. In this area both contenders had nothing to say. Also the bass was vastly improved; it gained kick, contour and might. Audiolab still sounded mightier, but the Arcam was more precise in the lower octave. The difference between the two got even bigger, when I attached the 8200CD as an USB-DAC – especially when using hi-res material. The progression in quality of the sound of the rDAC when playing HD material was nicely illustrated by the album “Before Sunrise” Robert Kubiszyn, recorded fully (each instrument separately) in the 24/88.2 resolution. In direct comparison, the CD issue sounded as if it would be compressed using lossy compression. Openness of the sound stage, reproduction of reverbs (artificial ones, but still...), clarity of decays and dynamics presented a much higher level. I would even risk a statement, that using hi-res material, the combination of rDAC/TeddyRDAC is a category A sound source.<br />

<br />

World class in price/performance ratio."<br />

<br />

Original text in PDF:<br />

http://www.teddypardo.com/images/rDac.pdf

[brab]

If I understand the reviewer correctly he has compared the various computer to rdac inputs and finds the USB to be the best. I have not compared computer to rdac inputs, but have compared the computer to rdac USB connection with my Rotel 965 to rdac connection using the Rotel as transport and connecting its coax out to the rdac coax input. In this comparison I much prefer the Rotel to rdac connection whether I'm using the computer's optical drive, or hard drive file to rdac. I would have thought that the asynchronous USB input to be superior, but not in my experience.

[brab]

Not exactly what you're asking but I've compared the rdac coupled with an ancient Rotel 965 as transport with the NAD you mention using both the NAD as transport with the rdac, and the NAD alone. The rdac-Rotel was much better in both comparisons.

[genvirt]

Hello,<br />

<br />

I suppose to buy one of the rDac, but have some problem:<br />

My computer stand far (~7m) from the PC, so couldn't use usb port (can buy some usb extender but its expensive like Ayre's QB-9 for example).<br />

Does any one have an expirience with wireless rDac model?<br />

Does it sounds good like coax or optical connection?<br />

<br />

Thanks.

[Mark Powell]

Interesting that you preferred the USB input. Hopefully, for our purposes, this will be an increasing trend.<br />

<br />

Two UK magazines have thought the power supply a severe weakness and report 'near high-end' performance when they built superior power supplies. But of course the customer should not need to do this. Provide a superior power supply and charge 50 dollars more. I suspect that many in both the UK and the US will remove it from consideration because of these reports and so they should. Not because it is poor, it is not, but it could have been better for a small price increase.<br />

<br />

The Benchmark seems to be getting a bit of a kicking lately, both in the UK and the US. only a while ago it was 'superb' or 'The best in our comparative test' (to quote the same two Uk magazines).<br />

<br />

I had similar hum problems with my Dacmagic. Fixed by cutting the ground lead to the external power supply/charger of my laptop. The power supply/charger ground was connected to the negative of the charge jack. As the charger supplies only 12V to the laptop, and both it and the laptop are plastic and double insulated I saw no harm in it. Some UK sold Marantz products have no ground connection even though their power supply is internal and the case is metal. Ok with a remote supply like my laptop, but not so good when you spill a glass of water over the Marantz.

[dizziness]

I love my rDAC but now am considering the Teddy Pardo rDAC PSU. At nearly $400 USD shipped, I'm wondering if there isn't a cheaper state-side solution. Ideas?

[theNewguy]

Hi everyone!<br />

<br />

I'm new to this site, as well as new to the audiophile world, so forgive me if I ask some stupid questions I'm actually looking at buying some nice active speakers (AVI ADM9.1, for example), but being new to this, I'm a bit foggy on what I actually need to get the FLAC from my HD to the speakers. Since the speakers are active, do I actually NEED a dedicated amp, or can I just use a unit such as the rdac to convert the music from digital to analog and then straight to the speakers? I know the AVIs use a toslink connection, but since I'm not using Apple I'm going to be using the asynchronous USB from a Windows 7 64bit machine. I decided to go with active speakers because I don't have the space or funds to spend on lots of separate components; basically, I'm trying to keep it as simple and cost effective as possible. In any case, I discovered this site about a week ago, and I've been trying to educate myself as much as possible by reading the reviews and forums, but it's a lot of new information to process. Hopefully you guys can steer me in the right direction.

[theNewguy]

Hi dizziness<br />

I just thought I'd ask you how you like those Audioengine A5s? I'm looking for some active speakers, but as much as I really want the AVIs, they're pretty pricey....

[bottlerocket]

Since the AVIs have a built in toslink DAC and an amplifier all you need is a Toslink compatible computer. If you are set on the AVIs, then I would not buy the rDAC as it will duplicate the DAC functionality that comes with the AVIs.<br />

<br />

Since you are using Windows, I think the simplest solution would be a USB to Toslink converter. <br />

<br />

Some options are<br />

Musical Fidelity Vlink<br />

M2Tech Hiface Evo<br />

<br />

There are lots of USB to SPDIF converters but not that many USB to Toslink conversion choices. The AVI people made a little bit of a weird choice when they decided to use toslink instead of USB because at roughly the same time that they gave up on USB, tons of USB DACs came out. <br />

<br />

Another option to consider is a toslink compatible computer like the Mac Mini.<br />

<br />

[theNewguy]

Thanks, bottleneck.<br />

<br />

As much as I love the AVIs, I'm not sure yet whether the wife will allow me to spend that much on speakers, though I still have hope! If not, I'll go with some less pricey speakers that, hopefully, would have more standard inputs. I also looked at the B&W MM-1 desktop speakers, which would require only a USB 2.0 to connect. According to their website, they also have a built in DAC (or DSP), although I have no idea about the quality of the B&W DAC chips...ah, so much to learn! The bottom line is, I'm a true beginner at this stuff and I have a ton of FLAC audio files on my PC that I'd like to hear in a quality way. Of course, the B&W are about $1300 less expensive than the AVIs, so I wouldn't expect them to sound nearly as good.