The Importance of Source in Audio
June 27th, 2009 by Rob N
We listen to music in our house. When everyone is home the stereo turns on in the morning and turns off when the last person goes to bed. A certain democratic hierarchy prevails that determines what is being played. There are five of us and each individual has his/her distinct preferences. Classical, rock, country, jazz and folk all fall into the mix. You pretty much know who made the choice by what is playing. Toleration and accommodation are the social graces that hold this together. We all have “favorites” that can only be played through headphones or when we are alone in the house. On Thanksgiving and Christmas the democratic hierarchy is suspended, martial law is imposed, and my wife rules the roost. We listen to Bach and Handel and the John Fahey and Nat King Cole Christmas CDs. Volume is important. She wants to hear the music while she works and still be in on the conversations.
Last Christmas I tried an experiment. I switched out the CD player with an HD-DVD player. The HD-DVD was reputed to be an excellent source for CDs and would be the equivalent of using a Blu-ray or high-end DVD player for listening to CDs. Nobody knew what I had done. At first, I was impressed by the results. The HD-DVD seemed to perform just as well as the far more expensive CD player. But within fifteen minutes my wife requested that I turn down the volume. Then, my son the musician said the stereo sounded “terrible” and suggested we turn it off. Unheard of in this household!
The problem was listener fatigue. Listener fatigue is why even your mother doesn’t want to talk to you for more than five minutes when you call her on your cell phone and/or speaker phone. (I’m sure she still loves you.)
Listener fatigue is also why many people do not listen to music as often as they thought they would on their new home theater system. For home theater applications the system will surpass most people’s expectations. A good surround sound system really does create a new dimension in the experience of watching a movie. Explosions are visceral; dialogue is crystal clear; when a door opens you can hear the hinges creak behind you. The sound is outstanding because DVD and or Blu-ray players compliment the receiver and speakers.
Music is different. With the exception of a well recorded SACD and SACD player, it will sound better in two channel stereo rather than surround. As my experiment suggests, the source is critical. If you want to know if your source is good, turn up the volume and sit down on the couch with your favorite brew. Even a bookshelf radio can play background music. The volume will reveal the strengths and weaknesses of your source. If you are still listening and enjoying the music when your cup is empty, you have a good source.
The reason the HD-DVD player sounded fine at first in my experiment is because it performed the essentials; there was a sound stage; the bass and the separation of instruments was articulate. The human brain has great software to compensate for the deficiencies in sound as long as there is rhythm and hooks. The Beatles conquered America on AM radio playing through cardboard speakers. Given time the software failed. Fatigue set in. The distortion was subtle enough that we could not identify it, but eventually it was irritating.
The problem we experienced with the HD-DVD player would have been amplified if the source had been an MP3 player. The iPod is unsurpassed for convenience and versatility. Two hundred hours of music in a device that can get lost in your coat pocket! It will sound great on your computer, earphones and in the car, but it cannot compare to the CD on a high end audio system. Technically, the difference is 1411.2 kbits of information on the CD as opposed to a maximum of 320 kbits in an MP3. This is significant. On a high end system the MP3 will steal the thunder from Keith Moons drums and mute the highs of an Itzhak Perlman violin solo.
Technology taketh away, but then it giveth back again. I have no doubt digital storage and MP3 compression is the future of music. The manufacturers have begun to respond to the quality issue. Peachtree Audio, for example, has recently introduced the Peachtree Nova, an integrated amplifier and DAC converter that will output your iPod and MP3 files to near audiophile quality. You can use it as a standalone unit in the music room, or integrate it with your existing home theatre receiver to handle two channel music and digital files.
The Nova really is an exciting product. You can see it at OneCall.com and read some of the buzz it is creating in the audio world on the AVS Forums http://www.avsforum.com/avs-vb/showthread.php?t=1095832. Now you can have the convenience of digital storage and near audiophile quality sound.
July 14th, 2009 at 8:14 am
You certainly jumped to conclusions based on a single incident with your HD DVD player. Your anecdote is meaningless though. I suggest you try at least a single blind ABX test. Make sure to level match within .1dB. I am confident that you and your family will not be able to consistantly pick out the more expensive source over the HD DVD player.
The same thing goes for properly encoded 320k mp3 files. Hydrogenaudio forums has done significant testing on the subject, and it seems that for the vast majority of the population, 320k is transparent. Most listeners report somewhere between 192k and 256k as being the threshhold for transparency.
Please look into the science of audio before rehashing the usual audiophile ideas.