Digital Systems…”Programming” A Loom
I’ve moved from Germany to France over the past few days for another presentation. Currently, I’m in Lyon and spent some off time today exploring the old city. This morning included, I took side trip to a shop in the old city where they still have a couple of working Jacquard looms, which employ a punched card system for determining the pattern that would be woven into cloth. Yes, this “programming” system was an early forerunner for early computer systems that also used punched cards to store programs and input/output data.
A Jacquard loom actually has a very complex system of punched cards that tell the system of treadles which threads to raise. I’m not an expert on weaving but my first wife had a large loom in our first home and I learned enough about how weaving works to see the relationship to computing.
The essence of digital processing is binary counting. A specific column on a specific row of a punch card can either be punched or not. This is a two state system and forms the basis of a stored program computer. In the world of digital audio, we use binary counting to store the amplitude of an analog waveform at specific moments or samples in time.
There’s a great deal of complexity to encoding digital audio but Pulse Code Modulation is a well-established system, which can capture and reproduces very high fidelity audio. In spite of repeated and incorrect claims by those advocating (and benefiting) from other methods including Pulse Width Modulation, PCM remains the primary production digitization process used in the world of audio and the best one.
I read a recent piece by Andreas Koch, a principal of Playback Designs, called, “The Subliminal Impact of Sound” at the Primephonic website. He suggests that DSD is somehow more “analog” sounding than PCM (as if analog sounding is a desirable goal!!). Aren’t we looking for accurate reproduction of sound instead?
You can read his article for yourself, but my favorite line is:
“As explained in an earlier article the frequency range of DSD does not have any cliffs, has a flat area for the classic audio range and then decays slowly at higher frequencies. Because of its very high sample rate the usable frequency band goes up to 1.4MHz for the slowest sample rate of 2.8Mhz.”
His claim that a DSD recording has “usable” frequency band that extends “up to 1.4 MHz” is pure baloney! What he has conveniently left out of his comparison is the fact that all of the noise present in the audio band (20-20 kHz) has been shifted up beyond 20 kHz and makes heavy filtering necessary on playback to remove the excessive noise in the ultrasonic range (you don’t want the ultrasonic noise making it to your equipment or speakers. A DSD 64 file doesn’t exceed the usable frequency range of a CD by very much…certainly not anywhere close to a properly done 96 kHz/24-bit PCM file. How easy it is to stray from the facts when you have a vested interest in advancing one particular over another.
High-resolution PCM digital encoding is a vast improvement in recording and reproducing music over any analog predecessor. It is more accurate, contains less noise, has less distortion, and is able to capture every dynamic nuance better than vinyl LPs, analog tape, CDs, and DSD files. Many will try to challenge this but the facts are the facts.
BTW The image used today is one I took of a miniature scene in a shop in Lyon, France. It contains a model of a weaving room with a Jacquard loom. Look carefully, it spooky cool.
Glad you had chance to read that Koch link Mark. Seems we need impaired brains to make a pointless comparison. Where will he go next ? Perhaps authors should provide professional provenance when acting the role of “expert”. As with folks over at CA, it’s “story time” !
Andreas Koch is very well qualified engineer and has the kind of experience that places him in expert territory. But it’s a problem when he carefully separate “supporting facts” and omits others.
Good point, but let’s be reminded that no degree or status renders one “professional”. That is the domain of “proofs”, which are the basis of “science”. Pseudo science is the realm of purposeful deceit. The audio world at large, is a parade of sales, damn the truth.
Keep standing up for PCMs true qualitys. Too many have climbed on the DSD bandwagon for reasons other than offering the High Fidelity community a path to improved reproduction.
What image?
The image on the front page of the blog associated with the post.
Mark,
My favorite part of the quoted text would have to be “classic audio range”. Does that include wow & flutter, drop outs, azimuth issues ? Maybe he should reconstitute the 8 track players like the Craig Powerplay that allowed “fine tuning” head alignment adjustments on the fly after each KA-CHUNK for a really classic analog sound…
My point exactly.
I am still trying to understand if DSD is worth it if a studio did in fact recorded a song with it in mind.
Lets say a studio did the recording with this.
Recorded to 2″ tape (Studer) and DSD64 (Sonoma System) simultaneously. Stereo Mixed from 2″ tape to 1/2″ tape and DSD64 simultaneously. 5.1 Surround mixes mixed from 2″ tape to DSD 64 in 5.1. Mastered to CD layer using 1/2″ tape. Mastered from DSD64 for SACD layer and DSD Downloads.
Would it make sense to purchase a 24/96 PCM format or a DSD2.8 format? Or we are just splitting hairs.
So much confusion on hi res at this time. Everyone is saying different things. I am eagerly waiting for your kickstart book to be released!
Oliver, a group of us did exactly that over a year ago at Snow Ghost Studios…but we included 96/24 PCM. The analog tape was out right away and the other two formats pretty close. I would stick with PCM because of the production limitations and HF noise.
It is satisfying to know about the quality of 24/96 PCM. However, it seems much a mute point since most wanted current popular music is offered only in CD format.
Very true…this is only going to be interesting to audiophiles.
Mark,
I am ok with the pundits using “more analog sounding”. Lets all agree though to get the recording to the home in the most accurate way possible, then the listener can filter and equalize as necessary. For fun sometimes I run my tracks through my Fisher receiver (amp / filter / harmonic generator) from the 60’s.
Some day we will have object based recordings where the home user can play mixer / producer and they can plug in any filters they want to make it more analog sounding:)
take care
I’m afraid I don’t understand the idea behind saying “more analog sounding”. It doesn’t mean anything other than to segregate digital recordings (which are inherently more accurate than any analog system yet devised) from analog recording and reproduction. I can agree that there may be different recording aesthetics and goals but to place “analog” on a higher level is misguided and incorrect.
“more analog sounding” means that the recording does not mix the sounds between which are up to 1 microsecond time periods
What?