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The following article, Digital versus Analogue, Part 1, covers the technical concepts surrounding analogue (or analog) and digital audio, the audio production and conversion processes, and the issues surrounding the creation of a digital audio stream, as well as the relative merits of each type of audio system. Every engineer, producer or audio-interested layperson should familiarize themselves with these basic concepts, to allow them to better appreciate the technical and practical applications and limitations of each of the steps that makes up the production process, many of which involve an analogue to digital or digital to analogue audio conversion process.

 

Digital vs. Analogue - Part 1

Analogue Recording

What exactly is analogue (analog, in American English spelling), as opposed to digital audio, anyway? Before we delve into that, let's quickly cover the fact that recorded audio is generally produced in stages - three stages, to be exact..... first, the basic audio tracks are recorded, after which they are mixed, and may possibly be edited during the mix process (though editing is not always performed), and finally, the completed mix is mastered before pressing/mass production. Either an analogue, or a digital process might be used at any stage. So, it's quite possible to have a completed project that has both analogue and digital aspects contained in it. For example, a recording might be made on analogue tape, but then be mixed down to a digital file on a computer, and then mastered and put on a CD, rendering a product that is ADD.... that's not a disorder...... the track is said to be Analogue/Digital/Digital. To be clear, a final product that is AAA would have been recorded onto analogue tape, mixed down to an analogue master tape, and mastered to an analogue final format, such as a vinyl LP record, or a cassette, with no digital conversions ever taking place in the process. Why is this important? Because it is the conversion process that permanently changes the audio from its prior natural state, as a collection of fluid, evolving waveforms, into a graphed-out, finite numerical representation of their net result at the recording input.... and somehow, that's just not quite the same thing. Now, let's further recall that all acoustic audio energy is kinetic energy - mechanical, and thus analogue by nature - and as such, the analogue component of audio cannot ever be fully replaced by the digital systems we have adopted for much of the technical processing used in modern commercial facilities. So, as a result, any process that uses a digital component, requires at least two conversions to be performed - the first, to convert the audio from waveshapes to numbers, and the second, to decode the number stream, so we can hear the result again in playback. Let's talk about digital conversion for a moment, and why this makes such a serious difference to what we hear....

The Mission: Take a constantly-changing, natural, infinite-resolution thing like a sound pressure wave travelling through air, and create a string of numbers that precisely represents it.... now, the issue, here, as you might note, is the sheer amount of descriptive information that needs to be created to do this. The thing is, audio waveshapes that we can hear, range in frequency from roughly 20 vibrations, or cycles per second, also called Hertz, or Hz, in abbreviation, all the way up to about 20,000 vibrations, or cycles per second....... now, imagine how much writing you'd have to do, to tell the story of every small detail of a waveshape's evolution, from its beginning to end (which could be a long sound going on for minutes), describing each tiny change of it's vibrational rate, content or loudness that appears, as it unfolds, when complete cycles of its existence occur, and repeat, as fast as 20,000 times every second.... as you can see, there would be pages of information, to describe even a couple of seconds of sound in this way.

The Solution: Using the binary number system (every number is only made up of 0s or 1s, in long strings) to make a machine-readable code, the waveshape's movements are sampled, much like a series of "snapshots", taken one after the other, at rates ranging from 44,100 samples each second, in standard CD-quality audio, up to perhaps 384 kHz (384,000 samples every second!), for the highest-speed studio recording systems, which creates a "list" of instantaneous sample points, each one of which is then assigned a number from a "table of mathematically possible values". This assigned number is one which fairly exactly describes the amplitude of the waveform at that exact moment in time, and so, when the list is re-assembled, the sample points are reconstructed in order, in a stream, and replayed at the same rate they were sampled at, much like watching a flip-book movie, and thus re-creating the waveshape.... more or less. To give an idea of the size of the "table of values", we need to understand the impact of wordlength, or, the total number of 0's and 1's in each of the "digital words" that represents each sample's assigned table value. Using a standard audio CD as an example, called the Redbook CD standard, audio is sampled (snapshots taken) and then "listed" in the audio file in "words" of 16 bits each, meaning that there are 16 0's and/or 1's in each word, or each word is 16 digits long. This 16-bit wordlength renders a total of 65,536 possible mathematical combinations, or different possible words to choose from in mathematically "describing" the dynamic level of each point in the sampled audio for playback, ranging from 0, written as 16 "0's" in a word, to 65,536, which is written as 16 "1's", as high a number as can be made with that wordlength. Now, the shocker - using a 24-bit audio system, the possible number of permutations increases logarithmically to 16,777,216 - a huge increase, for adding only eight more digits to each word - and yet, even this number of descriptive elements falls short of providing a perfect reproduction of the audio sampled into it. So....

The Problem: The "table of possible values" cannot possibly represent every possible option in all of nature's audio possibilities.... no matter how many "steps" are mathematically available in our table, Mother Nature's sounds have so many more subtleties - so many, that in analogue audio, there are no steps at all, only the constant, smooth evolution of each sound wave. In digital systems, however, their mathematical limits impose a need to quantize, or slightly-reassign some of the natural values that are initially sampled, so they can be assigned their numbers from within the limits of the table. We can think of this in much the same way as the mathematical "rounding" of numbers, to the "closest" possible value. So, for  example, to seriously oversimplify this concept, let's say, with our system, that we can assign a numeric value from 1 - 10, on our table , to any actual sample point we take. So, when we go and sample ten points from an actual sound, as the wave front rises, we might get measured values of, say, 1.1, 1.4, 1.5, 2.6, 2.9, 3.8, 5.0, 5.4, 6.7 and 9.5...... so, now, what do we end up with in our numeric table, after sampling, and quantizing (rounding) the values? We get "revised", quantized values of 1, 1, 2, 3, 3, 4, 5, 5, 7 and 10...... not exactly the smooth, natural wave we sampled in the beginning, at all, as the steps we end up with after quantization are all now "squared off" like a jagged staircase. The final nail in the coffin, is that they are now captured this way, and forever played back as they are encoded, in their quantized form, and not as they were sampled, and thus permanently locking-in the changes made by the encoding process. The result of this quantization error is called quantization distortion, and to the listener, it creates a notably hardened quality about the sound, making it seem more "sterile", or "cold", to quote some listener's opinions about it.

Click here for Part 2 of this article.

Audient ASP4816

ASP4816 Small Format Recording Console

The Audient ASP4816 provides all the key features of a large format recording console in a compact, cost effective form. Designed by audio guru David Dearden, and featuring Audient’s legendary analogue circuitry, ASP4816 is the perfect centre piece for production studios and educational facilities, and any application requiring no-compromise signal paths, pristine audio quality, a flexible feature set, and a small footprint.

The main input channels feature Audient’s renowned Class A preamp and 4 band EQ – a combination found in hundreds of ASP8024 equipped studios where many users no longer feel the need to reach for their outboard preamps and EQ. The console features a total of 40 faders, 16 bus routing, 6 auxes, 2 dedicated cue sends, 4 stereo returns, a stereo bus compressor and a comprehensive monitor section.

The Audient ASP4816 sets a new standard in small format excellence. Delivery is scheduled for February 2012.

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Contact Rock Shop Pro Audio for more information on the Audient ASP4816 and other Audient products.


 
Audient ASP8024

The Audient 8024 is a large format recording desk with world-class, uncoloured analogue audio circuitry throughout, an extensive feature set and impressive routing flexibility, plus the capacity to provide DAW control through the use of a Dual Layer Control module, giving the user premium quality and the very best of both the analogue signal and digital control worlds, and all at an amazingly reasonable price.

 

 

Contact Rock Shop Pro Audio for more information on the Audient ASP8024 and other Audient products.


 

 

2012.

The New Year promises some exciting developments in the pro audio realm. In fact, some of them are already here at Rock Shop Pro Audio.

Rock Shop Pro Audio is the perfect place to come to develop your vision for a custom recording, multimedia or home cinema environment, because we specialize in custom-designed systems and rooms. With decades of working professional audio experience, we know firsthand what you need to make a first-class audio or multimedia impression. Email Rob to discuss some cool ideas, without cost or obligation.

Rock Shop Pro Audio stands for top quality in all areas, and represents only manufacturers whose products are truly a cut above, in every respect, in the realms of both professional audio and video post, and high-end custom home cinema. Rock Shop's lines in both fields span an incredible array of components, from which can be created any system or environment imaginable, from the floor and walls up - specialized construction materials and acoustics treatments, racks, seating and furnishings, high-end audio and video equipment of all types, mounts and stands, patching and interconnect, power conditioning, and software for any audio or automation application - plus, the technical and consulting services and knowledge needed to get your customized system designed, built and running just like you want it to be. Thanks for stopping by.

 

A Note: If you would like information on something you see here, or more details on something not fully laid out on the site, please just email us with your inquiry to This e-mail address is being protected from spambots. You need JavaScript enabled to view it , or to This e-mail address is being protected from spambots. You need JavaScript enabled to view it , and we'll get back to you asap. Thanks for asking - we are here to help you.

A Further Note, in light of all the recent counterfeit audio equipment news: Rock Shop Pro Audio deals only in new, AUTHENTIC, ORIGINAL MANUFACTURER EQUIPMENT, sold to us through conventional distribution channels. We are a legitimate dealer of all the lines we sell.... NO COUNTERFEITS.... NO KNOCK-OFFs! All our equipment carries its FULL MANUFACTURER'S WARRANTY.

New for 2012:

Audient is proud to unveil the new ASP4816 small-format console.

Carrying all the same high quality audio, construction and design cues across from the flagship Audient ASP8024, the ASP4816 offers the same world-class audio quality, flexible routing and a host of top professional features in a small-footprint, 16 channel production-optimized mixing desk. It's exceptional design, pristine audio quality, smaller size and reasonable cost make the ASP4816 especially well-suited for production facilities, editing suites and academic institutions. Contact Rock Shop Pro Audio for more information on the ASP4816 and Audient's range of audio products.


In the pro audio field, Rock Shop Pro Audio specializes in analogue recording consoles and recording equipment from many of the world's top manufacturers. A small cross section of manufacturers follows. Click on the logos to see more about that company's products.

Audient was founded in 1997 and is renowned worldwide for delivering quality, affordable products that are in-tune with users working preferences and which deliver outstanding audio quality and ergonomic elegance. Based in Hampshire, England, Audient draws on a unique pool of design talent that combines unrivaled development expertise with a deep understanding of what is important to their customers. Audient's products are designed with passion, manufactured with pride and distributed internationally by professionals who share the goal of delivering products that "simply sound great."

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ATC, or Acoustic Transducer Corporation, was founded by designer Billy Woodman in 1973, with the simple mission of developing the world’s finest monitors. By designing and manufacturing every single component in-house, and hand-crafting each unit at every step, one monitor at a time, ATC has created monitors which are not only virtually perfectly accurate, sonically, but which are also aesthetic works of art - simply, the world's best.

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Eventide, located in Little Ferry, New Jersey, builds some of the worlds most advanced effects processing hardware, developed from the ground up, with care and creativity in design, to be the most useful effects devices ever developed. Known world-wide for their uniquely accurate and rich harmonizing algorithms, Eventide’s signature sound can be heard on recordings and broadcasts from everywhere on the planet.

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With the introduction of the world's first digital processor in 1971, Lexicon became the original world leader in digital audio. Since that time, Lexicon has continuously introduced ground-breaking technology to the audio industry, particularly in the realm of digital reverberation. Today, Lexicon processing can be heard on over 80% of all recordings - broadcast, film soundtracks, and music alike.

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Millennia Media is known around the world for their incredibly pristine, accurate and uncoloured circuitry, favoured by classical recording engineers, and those seeking the utmost in audiophile performance. Millennia Media’s line includes mic preamps, channel strips, equalizers and compressors, many of which offer the advantage of dual topology - two switchable circuit path types in one unit.

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Focusrite is an esteemed British designer and builder of analogue input and processing equipment, and also, the Liquid Channel, seamlessly blending the worlds of analogue and digital audio into one exceptionally flexible device.

 

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Gefell microphones bring incredible old-world German craftsmanship and hand built quality into the fore, with designs which not only embody these attributes, but which deliver a sonic richness and detail level uncommon at any price.

 

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Earthworks American-built microphones offer an unusually extensive frequency response and accuracy in reproduction which make them uniquely desireable for detailed audio sources such as choirs and acoustic instruments, as well as for reference measurement applications.

 

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Radial Engineering builds what are arguably the world's finest DI and transformer-coupling devices, as well as an extensive array of ultra-useful interconnect and audio distribution equipment, custom panels and touring rigs.

 

and many others.

 

In home cinema, multimedia and home audio lines, builders such as

 

 

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and

 

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make up just some of Rock Shop's wide selection of top-shelf brands.

Working closely with you, either in person, or often, over the internet, using your photographs, videos and measurements along with considerable personal discussion over telephone or email, as needed to clarify every aspect of your project requirements, Rob Dewar of Rock Shop Pro Audio will assess your specific room environments and the technical needs of each, and, with a firm conception of your vision in mind, design a customized, comprehensive package of requirements and professional advice to address each point, from the ground, up - Rock Shop can plan custom-designed, professionally-functional recording or monitoring spaces, advise on construction materials and techniques, room treatments and interconnect systems, mixing and switching systems, audio and video capture, monitoring, processing and storage, plus equipment racks, furnishings, accessories, and literally everything else required to complete your final vision, and will then specify each piece of material, hardware or software required to complete the project, by brand and model, if desired. To simplify things even further, Rock Shop Pro Audio can also then supply the entire specification to you, dealing from a wide selection of some 200 lines of exclusively high-end products, and will advise on their professional installation and system commissioning, plus provide initial troubleshooting assistance, free of charge, to get the system installed, connected and operating at top capacity.

No project is too big or too small - Rock Shop Pro Audio will work with you to clarify your vision, select the equipment you require to make it a reality, and then get your system running to specification in your environment, whether that's a small, basement recording studio, a surround home cinema, or a commercial theatre, club or video post facility. Working with a select group of associated professionals to address each aspect of your project, Rock Shop Pro Audio can provide the specialized experience, accurate technical analysis and detailed solutions you require, assembled from the best components, hardware and software available on the planet, to create a final result that is second to none in quality, capability and professionalism, and which meets or exceeds the original vision that inspired it.

Contact Rob Dewar at Rock Shop Pro Audio today, for a no-cost, no-obligation initial consultation of your professional recording, audio, video equipment or home theatre and home cinema system requirements.

 

Why Choose Rock Shop Pro Audio?

 
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