I haven't used a CD for a long time now, and most of my listening is done with computer based files. Even CD quality 16 bit/44.1KHz sounds better off the computer than using a CD transport IMO.
The difference is even more apparent when we start using higher sampling -96KHz and 192Khz files are getting scarily close to the best vinyl sound. Of course the proviso is that the recording technique, engineering , mastering etc has to be top class to take advantage of the superior resolution of the higher sampling rates. A badly mastered 96Khz recording can be beaten in sound quality by a a well engineered mp3, but when all things are equal the best high sampling recordings are simply awesome.
But don't expect miracles from any digital gear more than a couple of years old, sure some of the old classic dacs can sound "nice", but the real advances are recent.
Like wise , the rest of your equipment must be capable of resolving the extra resolution of hi-rez files.
Some of the digital gear I am using at June 2011 is: M2Tech Evo and Audiophilleo2 USB-SPDIF convertors, Sabre 32bit/192KHz and Lavrey DA10 24 bit/96KHz dacs. An Exadevices ExaU2I USB-I2S 32 bit convertor is capable of playing sampling rates up to 352.8 KHz, hopefully i'll find a dac that can keep up with it soon!
I'm using both Mac OS and Windows7 with PureMusic, Audirvana and Decibel players with the Mac and JRiver MediaCentre with Windows7.
So where does tube based audio equipment fit in with this new direction?
I can't see the sense of using equipment that is inherently colored or inaccurate with studio master recordings-surely if we can finally hear exactly what the recording engineers heard, then why color the sound with a slow warm "tube" sound.
Similarly , if a preamplifier, or any other piece of equipment is low on resolution, then it seems pointless to be using such high resolution digital files.
Of course, not all tube equipment is deficient in these areas, but a lot of it is.
It is important for all tube preamps and power amps to have low output impedance, or the ability to drive the following power amplifier, for a preamplifier, and the speakers for a tube power amp. If the equipment is well designed and has low output impedance, it will be able to drive it's load ACCURATELY , without the dips and roll-offs experienced with higher output impedance devices.
As an example look at this diagram of the response of a very expensive Single-Ended tube amplifier into a real world speaker load. The black line is the response into a speaker load.
I find it fascinating to read a review of a highly accurate and resolving piece of digital equipment and then discover the reviewer is using an amplifier much like this to review it. The ear is capable or hearing as little as 0.25dB difference in frequency amplitude response, but surely it is expecting too much to be genuinely critical about a piece of equipment using a tool like this. There's a 3dB variation in that response!
The next diagram is of a big powerful solid-state amp - the green line is the response into a simulated speaker load, same as above.
Now I suppose it sounds like I'm saying not to use tubes with digital, but not at all, I'm suggesting you have to be aware of how the equipment interacts with each other. Indeed, I think a really good quality tube preamplifier is a necessity with ANY system, whether it is digital or analog based. When the interacting impedances are right a good quality tube preamp (and the really good ones are rare) kicks everything into place. These days it's easy to remove the preamp as most devices have enough gain to do without a preamp, but they rarely work optimally, dynamics are the first thing to go and pretty soon you'll be spending less time listening to music as you wonder how it got so boring.
I haven't heard a single system of any type that hasn't been improved by the addition of a well designed preamp, that is capable of high gain into ANY load, flat response from a minimum of 20Hz to 20 KHz, again into any load and a minimum of coloration and distortion. Preamps can be designed to sound "warm" or "tubey" but the bad ones sound like this because they cant maintain a flat response into any power amp load.
A good tube preamp will bring out the very best of your hi-rez digital files, especially when the sampling rate equals or exceeds 96 KHz, but make sure it is a good one.
