The "great" sound of reel to reel explained

Ralph,
The truth of the matter is that the only way to make digital sound like analogue is to add distortion. This is not confined to the studio/professional-audio world; have you seen the measurements in the review of the the Playback Design MSP-5 SACD player in Stereophile? There have been many AES papers written on how adding distortion helps increase clarity and enhances low level detail. It is also common fact that most Audiophile find equipment "clinical" or "analytical" sounding often are the same with low THD and great linearity measurements. You can arrive at the logical conclusion right????

It is also common fact that most Audiophile find equipment "clinical" or "analytical" sounding often are the same with low THD and great linearity measurements. You can arrive at the logical conclusion right????

Carlos, not to put to fine a point on it but it appears that you have not understood what I have written or did not read it. You are correct in your statement above, but its important to understand why audiophiles use these terms to describe equipment that measures like that.

Its because it uses large amounts of loop feedback. This technique, while resulting in 'high linearity' (in a broad sense) and low THD comes at a serious price: loop feedback enhances the 5th, 7th and 9th harmonics used by the ear as loudness cues (as I have at this point mentioned several times before). That this is the case is easily proven by anyone with simple test equipment.

General Electric proved about 1965 or so that humans will not tolerate even trace amounts of this distortion, as we use these harmonics as loudness cues; arguably we are more sensitive to their distortion than we are human vocal ranges.

IOW, loop feedback violates a fundamental rule of human hearing when used to get low THD and 'high linearity'.

This is why your statement is true, although the reality that underpins it seems to be counter-intuitive. It is not a convenient fact, because linearity without loop feedback is difficult to achieve. However, if you think about it, linearity on paper is not real if the ear thinks its wrong! I guarantee that if we did not have ears, we would not play with audio devices; the ears are the most important things that any audiophile has.

With regards to the previous statement:

The truth of the matter is that the only way to make digital sound like analogue is to add distortion.

You can *mimic* analog in this way but it will not **sound** like analog! This is a common myth; you cannot increase detail and improve transparency by adding distortion, because distortion will mask low level signals (masking is a rule of human hearing BTW). Digital **already** lacks low level detail. So if you were to mask details even more, the difference between the analog and thus-doctored digital is immediately apparent.

Ralph,
To quote an Audiophile approved source, John Atkinson:

Perhaps his description of its sound being "analog-like" is a clue—for reasons that are not fully understood, a signal with very-low-level random noise added is sometimes preferred, on that it is more intelligible, to the same signal without such noise; See, for example, "Stochastic Resonance in Acoustic Emission," M. Friesel, Journal of Testing and Evaluation, 1999, and "The Benefits of Background Noise," Moss, Wiesenfeld, Scientific American, August 1995.

From the AES documents library:

Aural Exciter and Loudness Maximizer: What's Psychoacoustic about -Psychoacoustic Processors?-

In this study two so-called -psychoacoustic processors- are examined exemplarily by applying concepts, models, and methods of scientific psychoacoustics. Physical measurements of processed sounds and results of hearing experiments on speech intelligibility and sound quality (Aural Exciter) and loudness (Loudness Maximizer) are presented and discussed with regard to classic psychoacoustic models and potential new applications. Therefore relevant psychoacoustic facts, in particular the perception of nonlinear distortion, are reviewed.:

Author: Chalupper, Josef
Affiliation: Institute of Human-Machine Communication, Technical University of Munich, Munich, Germany
AES Convention:109 (September 2000) Paper Number:5208

Right. The first has nothing to do with my comments as it addresses a different issue of digital gear. The second does bear some relevance and does not contradict the findings that GE made in the mid-60s.

Carlos, are you suggesting that digital process don't add their own colorations?