Friday, August 31, 2012

Remembering Open Reel Tapes

Given that at this very moment, the music industry is currently retooling their product outlet into the online digital music download and streaming service realm, will the open reel tape go down in history as the best domestic music recording and playback format ever? 

By: Ringo Bones 

With the music industry now too busy to profit from the recent success of post Napster legalized online digital music download and music streaming sites like Pandora, Spotify and We7 over physical media, many true-blue hi-fi enthusiasts and serious audiophiles now wonder if one asks which domestic music format has a better sound quality than the good old vinyl LP – more often than not – they will be answered with the open reel tape. But is this symptomatic of the apparent lack of innovation in the music industry? 

Here in South East Asia, SACD and 24-bit 192-KHz sampled DVD Audio became as ubiquitous as hen’s teeth since 2005. I mean have you ever seen a Judas Priest or Ozzy Osbourne greatest hits compilation on SACD discs released by Sony Records on your local record store, never mind the Tower records and HMV here in Singapore and Hong Kong? And those “software doodads” supposedly to make your digital music downloads sound better than vinyl LPs - like the Burwen Bobcat – quite pricey at the time when I last saw it being demonstrated around Hong Kong and Singapore back in 2007 seemed to vanish without a trace back in 2011 with no cost-competitive alternative being offered. When it comes to “better-than-CD-music”, your only choice here in SE Asia are those weekend audiophile swap-meets where used vinyl and – if luck allows – used mint condition prerecorded open reel tapes are traded in a flea-market style setting.  

Commercially-produced prerecorded open reel stereo tapes for domestic use adopted the quarter-track – i.e. playable in both directions – format and companies like Barclay-Crocker gladdened the hearts of audiophiles by issuing many fine tapes right up to the demise of the format in 1986. Sadly, I only have 4 Barclay-Crocker style prerecorded open reel tapes – Lionel Richie’s Can’t Slow Down, Bon Jovi’s Slippery When Wet, An RCA Classical Music recording/compilation titled Music For Frustrated Conductors that came with a conductor’s baton in its packaging (I wonder how will RCA package this album for cassette or CD format?) and an Ampex open reel alignment / test-tape that came with the Teac X-3 Open-Reel Tape Deck I bought in a swap meet back in 1998. Sound wise, prerecorded open reel tapes have much more air and space in their recorded acoustic when compared to their vinyl equivalents. Though the open reel version of Bon Jovi’s Slippery When Wet have a definite DAT (as in 16-Bit 48-KHz sampled Digital Audio Tape mastered) timbre. 

Back in the mid 1990s, even a dog-eared condition but functionally perfect two speed - as in playable at 3 3/4 i.p.s. and 7 1/2 i.p.s. quarter track open reel tape decks started to fetch second-hand prices way above their Blue-Book resale values. “Notorious” examples are the Revox B77 and A77 open reel tape decks, models from Sony and Akai that dates from the early 1980s – and the Philips Black Tulip Open Reel Tape Deck, a superbly built 3-head machine (like the Teac X-3) that never really took off in its day started selling at over 200 US dollars. Vacuum-tube based tweaks could easily drive the second-hand sale price into the 1,000 US dollar price range.  

If you think listening to prerecorded Barclay-Crocker Open Reel Tape albums on your two-speed quarter-track stereo open reel tape deck is an adventure in itself this day and age, just wait when you try to record live music being performed by your local wunderkind in one. Believe it or not, an intrepidly diligent open reel tape enthusiasts can still find an unopened Scotch 111 blank open reel tape in most weekend audiophile swap meets here in SE Asia. The Scotch 111 open reel tape was often described by seasoned live recording enthusiasts as a “hoary old product” - even in the 1960s part of the Golden Age of Stereo because it had the history that descended linearly from the infancy of tape recording in the United States. Probably as far back as the post-World War II half of 1945 when Jack Mullin of 3M bought one of those “captured” Nazi-era German-made open reel tape recorders back to America to be demonstrated in front of the general public and prospective audiophiles in San Francisco. 

During the Golden Age of Stereo, not even the creator and manufacturer of the Scotch 111 open reel tape, the 3M Company, would argue that it was an “outstandingly good tape”. There were certainly other products available that offered much greater potential performance when it was finally discontinued around the latter half of the 1970s. But for a long time, the Scotch 111 reigned as the standard tape – because according to first-hand users – it was fairly consistent and widely available and it was the direct evolutionary heir to the first American ventures into magnetic recording. Open reel tape deck recorders worldwide were adjusted to suit the Scotch 111’s characteristics and when you were in doubt as to what open reel tape to use for a particular recording application, you could almost always fall back on the old Scotch 111 with a reasonable expectation of getting the magnetic recording job done adequately.     

Friday, August 17, 2012

Online Digital Music Streaming And High End Audio: Never The Twain Shall Meet?

Given that it could become the main music distribution system for the rest of the 21st Century, will online digital music streaming and online digital music downloads ever achieve audiophile status? 

By: Ringo Bones 

A recent research done by music marketing groups had projected that streaming music services like Spotify and WE7 will generate up to 1 billion US dollars in revenue for the global music industry this 2012 – which represents a 40% increase over previous years. But given that online digital music streaming services and online digital music downloads are fast overtaking the good old-fashioned music store that sells “physical” music media like CDs, DVD-Audio discs and SACD discs, are the major music labels who now embrace this newfangled way to sell music ignoring the sound quality issue that are voiced by committed high-end audiophiles with almost unlimited disposable income? 

Sadly, the sound quality of their product only mattered to major music label bigwigs during the “Golden Age of Stereo” of the 1950s and the 1960s. During the oil crisis of the 1970s when making vinyl LPs are precipitously getting more and more expensive, major record label bigwig executives adopted the mantra of just good enough – instead of as good as possible – when it comes to the aspect of sound quality. And by the way, when CD was introduced around 1983 – its linear PCM 16-bit 44.1 KHz sampling system was 1970s technology. Are music company bigwig executives ignoring dedicated audiophiles with purchasing power rivaling NASA at their own peril?   

Back in 2005 as I visited audio / hi-fi fairs here in Southeast Asia, there were companies exhibiting digital processing devices supposedly to make your MP3 downloads sound closer to Red Book spec CD – some boasts that it can make them sound like late 1950s era stereo vinyl LPs. But these were expensive devices back then. In 2012, none of these make your digital downloads sound like vinyl are to be found. Instead, die-hard hi-fi enthusiasts here in Southeast Asia now talk about trading swapping pre-owned vinyl LPs given that SACDs and 24-bit 96-KHz sampled DVD-Audio discs seems to be getting extinct in front of our very eyes in this part of the world. Some say digital music downloads will probably sound like good old stereo vinyl LPs by the year 2070. 

Friday, August 10, 2012

Are Piezoelectric Ceramic Cartridges Hi-Fi?

Even though its innards are composed of a piezoelectric material that’s only been mass produced after World War II, why are piezoelectric ceramic cartridges still not considered audiophile enough for high fidelity stereo vinyl LP playback? 

By: Ringo Bones 

From a scientific / engineering standpoint, it seems that the “lowly” piezoelectric ceramic cartridge appears to be more advanced than your typical mainstream moving coil and/or moving magnet cartridge for high fidelity playback of stereo vinyl LPs. And yet in this day and age well into the 21st Century, it is the moving coil and moving magnet types that dominate the now esoteric – yet so hip – scene of the vinyl LP playback niche of the audio world. But why is it that a diamond stylus sculpted to almost nano-engineering precision will only be viable for high end high fidelity vinyl LP playback when its mechanical undulations after reading the vinyl LP’s microgrooves are connected to a mechanical actuator/pickup composed of a coil of wire or magnet instead of a Bimorph Rochelle Salt, ammonium dihydrogen phosphate or a barium titanate / combination lead titanate-lead zirconate piezoelectric ceramic cartridge? But first, let’s briefly examine how LP became the dominant Post World War II high fidelity music playback medium. 

Modern vinyl LP playback for the home can trace its origins back to June 1948 when Columbia Records introduced the microgroove 33 and 1/3 rpm long-playing (LP) record as a better sounding and longer playing time alternative to the 78 rpm shellacs. Thanks to the work of Hungarian-born Peter Goldmark who, with the help of William S. Bachman, invented the LP disc in a laboratory set up by Columbia a few years before. Goldmark’s new record was cut in hair-width grooves, utilized a new electronic equalization system – i.e. the now standard for LP called the RIAA playback equalization where all of the music recording industry eventually all adopted back in 1953 – to balance the tone along all portions of the groove, was pressed in non-breakable vinylite plastic, and was played in a new turntable that recorded steadily at a new speed of 33 and 1/3 revolutions per minute. 

Not to be outdone, rival music recording industry bigwig RCA Victor thereupon issued their 45-rpm “donut” discs – and eventually the “hi-fi world” adopted both 33 1/3 and 45-rpm speeds as standard for post WWII vinyl record playback. Eventually, RCA Victor also produced its very own version of 33 1/3-rpm vinyl long-playing records from their burgeoning Classical Music catalogue – and thus paving the way for the Golden Age of Stereo of the 1950s onwards. 

Till this day, piezoelectric ceramic cartridges have a very glaring advantage over their moving coil and moving magnet cartridge counterparts, they can produce and output signal that can reach a peak of 1 volt – as opposed to high end moving coil cartridge that are as expensive as a South Korean made 4-door sedan whose signal output measures only around 5-microvolts or so. This allows ceramic cartridges to be connected directly to the line-level / AUX input of your preamplifier with only a passive RIAA circuit for tone shaping / tonal compensation. 

But sadly, ceramic cartridge design seems to be stuck in the 1950s because the stylus compliance of a typical piezoelectric ceramic cartridge is poor compared to either moving coil or moving magnet cartridge, so greater tracking force is necessary in using ceramic cartridges – which will inevitably exacerbate record wear. Ceramic cartridges also require about 1-megaohm load resistance – whereas most line-level / auxiliary / AUX inputs have far less – typically about 50-kilohms and even less for some solid-state preamps – which means bass output will be drastically cut. Though vacuum tube preamps and power amps in the 1950s with an EF86 tube input stage usually has input impedance greater than 1-megaohm – like Peter Walker’s famed Quad II power amp for example. 

And as a reminder for those folks way too young to remember – Bimorph Rochelle Salt Crystals used in some very high output piezoelectric ceramic cartridges are very sensitive to environmental conditions and should not be kept and used in places where the temperature exceeds 125 degrees Fahrenheit. But if top high end vinyl LP playback cartridge manufacturers try to develop this very instant their own line of high-end piezoelectric ceramic cartridges with the advantage of a really high signal output with much improved mechanical stylus compliance so that tracking force is equal to that of most moving coil and moving magnet cartridges – who knows where vinyl LP will be a few years hence. By the way, despite of the drastically cut low-frequencies, those cheap and cheerful piezoelectric ceramic cartridges can replicate a well-recorded well-thwacked snare drum better than similarly priced moving coil or moving magnet cartridges.    

Thursday, August 9, 2012

Interstage Transformers: Mere SET Amp Design Afterthought?

Even though it offers audible and engineering improvements in designing and building single-ended triode amplifiers, do most SET amp designers still view interstage transformers as a mere engineering design afterthought? 

By: Ringo Bones 

Most zero feedback single-ended triode amplifier designers seem to have yet to understand that directly heated triode power amp tubes that date from the 1930s – including the famed 300B tube – are not that easy to drive and therefore necessitates the need of a well-designed interstage transformer to exploit their full sonic potential. But why are well-designed interstage transformers still a rarity in the world of zero feedback single-ended triode amplifiers?

Books and data on how to design interstage transformers seem to be forgotten as soon as the world discovered solid-state semiconductor amplifier design. Folks who know or have datasheets on the correct winding configuration and transformer core material to be used are very reluctant to share their secrets. Getting a symmetrical square wave out of an interstage transformer that you’ve desined and wound yourself is still one of the blackest arts in the realm of vacuum tube audio. Unscrupulous designers often steal from those who successfully designed one then claim it as their very own design.  But still, SET amplifiers incorporating a skillfully designed and built interstage transformers, are one of the most amazing wonders of the hi-fi world – sound wise. 

Given that the most powerful directly-heated triode tubes specifically designed for audio use that are designed during the 1920s and the 1930s only offer 10-watts or so, audio designers often press directly-heated triode transmitter tubes in designing single-ended triode power amps that offer greater power output. For example, an 845 directly-heated triode transmitter tube is capable of 50 watts and yet even driving it with mere capacitor coupling from the plate of the 300B tube to the grid of the 845 transmitter tube will only give you 28-watts or so.

 The interstage transformer acts as a parallel choke on the 300B making it as a driver tube. At about 28-watts, the impedance of the grid of the 845 transmitter tube (like all other directly-heated triode transmitter tube designed around the 1930s) drops dramatically, necessitating the need for more current from the previous amplifying stage to drive the 845 tube further. That’s where the interstage transformer takes over, providing additional current to drive directly-heated triode tubes to their maximum designed power output.  

And not all interstage transformers are designed – and even created – equal. A case in point is the beautiful WAVAC 4304B SET amplifier that uses the famed Nobu Shishito designed inverted interstage transformer, is probably the flat-out the best amplifier I’ve heard – tube or solid-state. Nobu Shishito’s inverted interstage transformer designs are very noteworthy for their delicacy and blinding transient speed – more than good enough to trick you as if you are listening to an actual live musical performance!