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ASIO v K Mixer v Kernel Streaming

May 6th, 2009
by Steve.
1 comment

Computer audio seems to generate emotions when discussing what products to use that really are odd. Why do people get  so wound up?  I’d be interested in your comments. Ideally one would take a computer, connect a good DAC and play one’s favourite music using one’s favourite app.

If only it were that simple to get a great sound from CA.  The more I experiment the more I realise that CA is absolutely similar to analog audio or indeed any audio when taken seriously.  Every change is audible. Assuming one has a good enough system.

Of course, just because a change is audible doesn’t mean it matters.

The expression bandied about on forums about Computer Audio is bit transparent.  The theory is simple: it’s getting the bits from the Hard Drive out of the computer without them being manipulated/changed in any way.

I’ve tried many music playing apps and they all seem to sound subtly different.  Even different releases of iTunes are reported to sort different.  Life is far to short to bother to try different releases.  As they say, I tried it once and didn’t like it.

For convenience for quick playback I tend to use VLC www.videolan.org.  It seems to play almost everything audio and video and can even stream stuff over  my network.  It works well for Radio Paradise too.

If I want to get serious say when I’m comparing DACs I tend to use Foobar.  It’s not my favourite user experience but it is easily configurable. For use under Win XP it’s possible to use the ASIO add in to bypass the K Mixer (assuming you have a suitable sound card). I use the M-Audio Transit. For Vista the WASAPI add in also bypasses the Windows (Kernel Mixer aka K Mixer) mixer.  With volumes set at 100% one should be achieving bit transparency and the sound should be just that little bit cleaner, less splashy and the space between notes will be greater somehow.

CA still never gets truly close to good CD playback.  Not yet for me anyway.  And it’s not ’cause I haven’t tried hard.

It’s a bit simpler with a Mac (the classic Mac and a DAC route) assuming you remember to set the right bit depth and bit rate in the Midi settings but I can’t say it sounds any better.

Another DacMagic power supply trial

May 4th, 2009
by Steve.
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Decided to use Fleetwood Mac’s Rumours, but slightly more unusually, the DVD-A rip so the source is 24/96. Unlike quite a few DVD-As, this one appears to have some content above 22k. Amazing though, that given the total available dynamic range they still needed to ‘clip’ the recording.  Still sounds rather good though.
To start I compared the standard power supply with the Maplin L54BR.  Pleasant surprise, the Maplin delivers a subtlety of delivery that doesn’t emphasise any particular instruments. The original PS, in comparison, seems to make the bass line and the hi-hat a little more obvious in the mix of Dreams and decreases the importance of Stevie Nick’s voice.

Using track 7 , The Chain, showed the original as having a slightly ‘sharper’ delivery, more detail perhaps but certainly less music. The main difference was in the low end but this changed the overall presentation. The Maplin just delivered more music but in a controlled and balanced manner.

I then dug out the 500VA transformer I’d tried before – now in an aluminium box and with a ferrite on the output – in common with the original Dacmagic’s supply.  This PS delivered more power to the presentation, more extension apparently  but was slightly slower. It had better separation of instruments, but not really more music.

The more comparisons of power supplies I do with the Dacmagic the more impressed I am of the overall balance of the design.

I will carry on using the Maplin PS.  It is easier to hide away, as it isn’t a walwart, and more importantly it improves the performance making it just that little more balanced and even handed.

The music playback system was a HP2133 netbook running Foobar and ASIO drivers connected by USB2 to a M-Audio Transit sound card which was connected with a  Chord Optichord to the Cambridge.

HDMI cable silences my listening room

Apr 14th, 2009
by Steve.
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Having a PC in my listening room was convenient as I have often been experimenting with different audio playback apps, sound cards, and all the various drivers like ASIO and Kernel Streaming.
The problem though was the noise of the PC. All that investment in a great hi-fi system and a signal to noise ratio destroyed by computer fans.
The solution came to me last week and it was simple.
OK, I have an advantage: a cable company as a client. Nigel at Chord was kind enough to send me a 5m HDMI Silver Plus cable and two DVI to HDMI adapters.
The experiment was to move the PC outside my listening room and then to use a 5m Chord HDMI and 5m USB cables to monitor and control the PC.
The worry was running a good monitor at 1920 by 1200 over a 5m HDMI cable. Would the image quality be reduced? The image was absolutely fine and so much so that I temporarily tried a 10 m cable which worked just as well.
Definitely a result. Noise removed from my listening room, the hi-fi sounds significantly better. The computer is no harder to use. I’ll use a USB DVD drive near the monitor for normal stuff but walk the few metres to use the Plextor Premium CD drive for serious ripping.

Cambridge Audio Dacmagic

Jan 18th, 2009
by Steve.
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I’ve had a the new Cambridge Audio Dacmagic for maybe a couple of months now and its not disappointed.  For two hundred pounds it’s fabulous value.

I started off running it in and using it connected via a Chord Prodac Prodigital coax cable from my Squeezebox 3.  It’s a great match for the SB3, delivering increased clarity and drive over the SB3′s line out. Sort of seems in the right price range for an upgrade to the SB3 as well.

Next was connecting it via USB to my HP Note 2133 to play internet radio.  Using Radio Paradise’s 128AAC stream as the primary source – a great souce of quality music with great sound – it sounded flat and boring.  What was surprising was just how easily it connected and Win XP recognised it straight away.  Really plug and play.

Adding a M-Audio Transit sound card connected via USB and then feeding the output from the Transit via a Chord Optichord optical cable into the Cambridge changed the sound quality completely: dynamics returned, life and energy returned and music was fun to listen to again. Internet radio can sound surprisingly good.

I do have an even better internet radio player but I’m not free to talk about that yet.

Two or more things to try with the Dacmagic yet: a larger power transformer and changing to ASIO drivers as these are supported by the Transit. Might even try the three filters sometime.  I reckon that there is loads more to get out of it if only I had enough time to experiment.

More on these another day.