[Roam]

A tube output stage would solve the problem of slewing, but it can create problems of its own. For one thing, all that MHz range noise is now getting dumped into the rest of the system as RF noise, it's amplified by the tubes and radiates into the rest of the DAC through both the air and wiring. That RF is going into the next stage of the system through the interconnects, which will likely also serve as antennas, further spreading the noise through the air. This noise then arrives at the preamp or amp, yet another chance for slewing distortion to set in, and this continues through the rest of the amplification chain.

The best result is an amplification system which is being unduly taxed by amplifying all this high frequency noise which we can't hear, the results of which may include softened dynamics along with a feeling of strain. In a worst case scenario, the amplifier will actually self-destruct from trying & failing to amplify RF range signals. Somewhere in the middle, we have the common case of the RF noise modulating with the signal and introducing distortion, this is usually perceived as a glare or fatiguing quality to the sound.

This is why I believe in killing the noise at the source with a passive filter. It greatly eases the requirements of the analog output stage on the DAC and makes everything else a lot more straightforward.

 

[Faust2D]

Read this article. http://www.fortunecity.com/rivendell...io/Adagio.html

The ultrasonic output is what might be making it sound good. There have been many attempts to actually create it using filters.

 

[Roam]

Quote:

Originally Posted by Faust2D /img/forum/go_quote.gif Read this article. http://www.fortunecity.com/rivendell...io/Adagio.html The ultrasonic output is what might be making it sound good. There have been many attempts to actually create it using filters.

Note that his design uses an interstage transformer and analog stage which acts as a low-pass filter, all the MHz range RF garbage is gone. Yes it will have ultrasonics, but it will be within the range which most amplifying devices can handle without slewing.

 

[Faust2D]

This is exactly what I was talking about, carefully designed DAC tube output stage.

 

[Eagleboy]

Quote:

Originally Posted by Crowbar /img/forum/go_quote.gif No, the environment is part of the instrumentation that forms the sound. The guitar's wooden body alters the sound produced by the vibrating strings. But the sound of the guitar is that of the whole thing, not the string. The environment is just another lair, and the way physical objects affect sound is something natural to the ear, incomparable to the distortions you get from electronic equipment.

The environment is as much a part of the instrumentation of the sound as the reproduction is part of the instrumentation of the sound. Simple enough to understand, no?

And, you're talking about reproducing perfectly. How can you reproduce something perfectly if the sound changes given the environment it was produced in? And you might say "I want to reproduce the music as it was on 2:00pm at ATM at the REd Bird recording studio located at 427 Freebird Lane, Nantucket Balls, Georgia". But, you can't. Microphone placement, recording engineers, work flow, etc. are all far too many variables for you to work around. The MOMENT you step outside of that recording studio that you probably were never in (and thus don't even know what it sounded like to begin with), you are listening to a "false recording".

As an guitar maker, player, and recorder, I can tell you that an inch goes a mile in terms of microphone placement and how it affects the timbre of the instrument in the recording. No matter what mic and mic placement the engineer decides on, it will not be an accurate depiction of the instrument. It might sound really, really good, but the guitar itself probably sounds better - hell, maybe even worse if the recording engineer did a good enough job recording the instrument (meaning, the recording engineer will record an instrument to sound good - even if the instrument sounds like crap. They want to give people something pleasurable to listen to, no? They even alter tone compression and balance based on how the recording sounds on cheap computer speakers, earbuds, and car stereo systems, so that people will enjoy the music wherever they are).

You are chasing the pink elephant, here. ONCE AGAIN, listen to what sounds good to your ears, because as far as you get to catching that pink elephant, your master source will never be perfect or distortion free.


PS - Distortion doesn't have to be in the digital or reproduction realm. I can tell you with 100% confidence that distortion exists within the physical world. The environment DOES distort the raw sound - which is exactly why music played in different environments sounds radically different. DISTORTION = ALTERATION. Look it up, or talk to a high school physics teacher.