Cassette Tapes: Less Than Ideal High Fidelity Audio Medium?

Despite the 21^st Century romanticism on how better cassette tapes are in comparison to CDs, MP3s and other digital mass music media, are cassette tapes just “too fragile” to be a hi-fi audio medium? 

By: Ringo Bones 

Romanticism and a rose-tinted view of the heyday of the cassette tape had been on the up-rise on every social media network since the first decade of the 21^st Century that sometimes I wonder if these people were actually there first hand – as working musicians and amateur musicians – with only expensive and fragile cassette tape recordings to fall back into when rehearsing for their respective cover-song. Maybe I’ll just ramble yet again on my “bad experiences” of the cassette tape during the 1980s up to the early 1990s. 

Unlike those CD transports found in cheap boom-boxes and table-top AM/FM cassette recorders of the 1990s, tape transports found in these devices tend to eat cassette tapes. Although cleaning with 90-percent isopropyl alcohol on top-flight cassette tape decks, especially the capstan and rubber pinch-rollers on a regular basis means that cassette tapes being eaten on reasonable quality hi-fi decks are an extreme rarity, cheap boom-box CD transports are not known to damage CDs with their “overactive” ultraviolet lasers. 

 Another cassette tape – in fact every magnetic recording tape as well - weakness is that when they are exposed to a sufficiently powerful magnetic field, they tend to go dull that is they loose their high-frequency response. This problem is often experienced by electric guitar and electric bass players where a cassette tape copy of the song they are supposed to rehearse is tossed in the electric guitar case or bass guitar case causing the recording to become dull and some parts to drop-off or be erased completely upon exposure to the powerful magnets of electric guitar pickups or bass guitar pickups. Open-reel tapes – as in master tapes of bands whose budgets allow them to work on one - in transit often avoid this problem by being stored in a mild-steel case that acts as a magnetic shield to prevent dulling and erasure of high frequency signals – i.e. cymbals and lead guitar parts – but when was the last time you’ve seen a cassette tape housed in a magnetically shielded mild-steel housing and case? 

Whatever Happened To Audiophile Cassette Tape Recordings?

It may seem like oxymoron back in 1995 until today, but was there ever a time where “audiophile cassette tape music recordings” were commercially marketed? 

By: Ringo Bones 

Back in 1995, the phrase “audiophile cassette tape music recordings” may seem oxymoronic and nonsensical to most audiophiles who are bought and sold by the budget CD player wonder called “Marantz CD 63 SE KI Edition”, but there was indeed a point in time where premium audiophile cassette tape music recordings are commercially marketed and can be bought from your nearest music store. Back in 1980, Mobile Fidelity Sound Lab president Herb Belkin after introducing Original Master Recording LPs back in 1977 tried to introduce the cassette tape version of his “Mo-Fi” LPs called the Original Master Recording Cassette that were recorded in real time – not via high-speed dubbing – that made available audiophile quality contemporary popular music, hard rock heavy metal and Jazz to almost everyone, including 1980s era budding audiophiles. Later in 1980, Mobile Fidelity Sound Lab later released Geo-Tape, an audio cassette tape deck alignment device for consumer use. 

Unbeknown to Mo-Fi president Herb Belkin, cassette tape playing devices on the lower end of the food chain have the propensity to “eat tape” – i.e. their capstans literally pull the tape out of the shell and crumpling the tape forever ruining what audio signal recorded on it. Unlike the advent of cheap boom-box CD playing devices of the 1990s, these don’t have ultraviolet lasers that burn the recorded pits of music CDs. I think the last “audiophile” cassette tape music album sold commercially was back in 1991 when the cassette tape format of Skid Row’s Slave To The Grind album where the tape used was of the cobalt-doped Avilyn type and it even said on the cover “recorded on premium cobalt Avilyn tape. But was it because of the excessive high-frequencies recorded on the master tape of the Skid Row’s Slave To The Grind open reel studio master tape that resulted in too much – and messy – treble? At least you can now listen to the album to freely judge for yourself. 

Demagnetizing Dilemma: How Often Should We Demagnetize Our Cassette Tape Decks?

Though cassette tape deck manufacturers recommend cleaning record and playback heads every 12-hours or so, but how often should we demagnetize them to insure optimal performance?

By: Ringo Bones

Near the end of the 1970s, many hi-fi enthusiasts hailed the affordable high-performance cassette deck as the consumer electronic miracle of domestic audio. Unfortunately, there’s a topic that even today – way, way after the hi-fi cassette tape’s heyday – that sill remains nebulous and esoteric, as in the subject of cassette tape deck record and playback head demagnetization. Or more importantly, how often is enough to insure optimal function?

Until it is removed, a low-level of “permanent” magnetism builds up on playback heads in normal use and on record heads also if the record bias waveform is not perfectly harmonically pure or if the record bias is turned on and off too suddenly. Before the advent of cassette tape decks, owners of domestic open-reel tape decks often use dedicated hand-held demagnetizers to demagnetize the record, playback and even the capstans and tape paths. Unfortunately – unless you have the requisite skill and confidence to disassemble and reassemble the cassette tape deck you currently own – hand-held demagnetizers are a non-starter for use in cassette tape decks, especially car stereo units.

Over the years, dedicated electronic-based battery powered cassette tape deck demagnetizers – like the Nihonbashi ED-126 Electronic Demagnetizer and the Milty Magnet IX cassette tape deck demagnetizer – are my preferred accessories when it comes to demagnetizing cassette tape decks, including car stereo units. Electronic cassette tape deck demagnetizing units work by introducing a lightly damped 1-KHz alternating current waveform across the record / playback head of a typical cassette deck that usually lasts about one second and registers around +10 dB on the VU meters of tape decks for those who have them. Thus most electronic cassette tape deck demagnetizer manuals warning users to turn down the main volume of their amplifiers when using it since it will introduce a very loud 1-KHz squeak to their loudspeakers. Given that these electronic cassette tape deck demagnetizers are housed in a cassette tape shell shaped enclosure and usually powered by a single wristwatch battery, they are virtually foolproof to use even to a novice audiophile.

Most electronic cassette tape deck demagnetizers’ manuals recommend to using it to demagnetize your cassette decks heads after every 40 hours of use. During the 1980s, when cassette tape was the virtual de rigueur format of budding audiophiles, I tend to demagnetize my decks once or twice a month depending on frequency of usage. Other kinds of cassette tape demagnetizers use a tape-like strip magnetized with a series of alternating polarities – and virtually looks like a dedicated cassette head cleaning unit. There’s even a cassette tape deck demagnetizing unit that uses rotating permanent magnets to demagnetize the record / playback head of your cassette tape decks. Besides the electronic cassette tape deck demagnetizer units, the other types were, over time, rejected by cassette tape audiophiles because they are either ineffective – the tape strip type – or does more harm than good – i.e. the type using rotating permanent magnets.

Whatever the magnetic flux source, the working principle behind cassette tape deck demagnetizers is that the fluctuating magnetic field must gradually weaken until it fades out altogether; otherwise it will leave behind residual magnetism, which is precisely what you are trying to eliminate. Thus the use of electronic cassette tape deck demagnetizing units of a lightly damped 1-KHz alternating current waveform whose voltage dies out slowly over one-second duration.

In a properly operating cassette tape transport, the AC bias generating during the recording process tends to demagnetize separate record and erase heads so they normally are unlikely to need additional degaussing or demagnetization. Combination record / playback heads may be similarly protected. Tape guides and the playback heads are the parts most likely – from a theoretical standpoint – to become magnetized. In my experience as an audiophile and amateur musician for 27 years, I’m not sure that any type of demagnetizer can successfully demagnetize a capstan, but I’ve seldom found a capstan that needed it.

Signs of playback head magnetization include a noticeable increase in tape hiss. If left untreated, the cassette tapes you are listening to may suffer an irreversible loss of high frequencies. The loss will be less likely if you are using metal particle – Type IV – tape, whose high coercivity make it inherently more difficult to erase than other tape types. An FM radio station I used to intern back in 1987 has a DJ that tend to let 100-hours or more to go by before demagnetizing the station’s cassette tape decks. If you wait until hiss builds up or highs are erased, it’s too late. So I tend to demagnetize ever 30 to 40 hours or so back then. But some cassette tape deck manufacturers – Teac amongst them – have recommended against demagnetization. Part of their reasoning may be the danger of inadvertently magnetizing parts in the tape path, particularly if one uses the most aggressive hand-held demagnetizers – probably stems back during the days when Teac still makes those wonderful sounding open-reel tape decks that we still covet until this day.      

Recording CDs To Cassette For A Better Sound Quality?

To those old enough, do you still remember the time when music on CDs tends to sound better when they are recorded onto blank cassette tapes? 

By: Ringo Bones 

Let’s face it early 1980s era CD players may have been built like a tank – like that of cassette tape decks of the period. But when compared to contemporary universal disc players that can play CDs DVDs or any 5-inch diameter disc, the sound quality of early 1980s era CD players leaves much to be desired. Even though in the 1990s we finally have names on the “audio gremlins” that plague the Redbook Spec 16-Bit, 44.1-KHz digital audio – data induced jitter for example – why is it that early 1980s era CDs sound quality improves once it is transferred to cassette tapes, 8-Track, Elcaset or any other analog magnetic recording media? 

Even during the Golden Age of Stereo, audio engineers and audiophiles already know that high-order very steep cutoff low pass and high pass filters are deleterious to perceived sound quality. The reason why CDs – and even low data rate MP3 audio files – tend to sound better when recorded on analog magnetic media like cassettes, Elcaset, 8-Track, etc, is that analog magnetic tapes doesn’t require a high order low pass filter as an “anti-aliasing filter” to remove signals that doesn’t fit in to the Nyquist Criterion of Redbook Spec CDs. Any signals too high in frequency to be recorded in analog magnetic recording media just rolls off gently at a rate of 6 dB per octave. 

Why early CD players tend to sound worse than their more contemporary counterparts is because anti-aliasing filters with very good subjective sound quality were very difficult to design back in 1982. It was Philips of Eindhoven, Netherlands that were the first to come up with an oversampling digital filter – which is all about digital signal processing algorithms – that resulted in a better sound quality than competing anti-aliasing filters of the time, but digital signal processing was still at its infancy in comparison to what we can do during the 1990s never mind today. While Sony in Japan struggled on with impractical ninth-order analog brickwall filters, Philips had no choice as they were unable to make reliable 16-bit converters at the time of the CD’s 1982 CES debut. 

By using oversampling and noise-shaping way back in 1983, Philips could make their proprietary 14-bit converter for 16-bit 44.1-KHz Redbook spec CD work with 16-bit resolution. Even though both Philips and Sony’s CD players costs around 750 US dollars once they became available back in 1983, a similarly priced machine in the mid 1990s can easily show it a clean pair of heels sound quality wise. Today’s similarly priced machines are even better. Would the hi-fi cassette tape decks role during the early days of CD is a “widely available digital-to-analog-converter to make early CD sound better”?

BBE Sonic Maximizer: Cassette Tape Friendly?

Eve though many musicians who can see past it’s rather “showy sound enhancement abilities” now hate it, was the BBE Sonic Maximizer cassette tape friendly enough to qualify as its “soul-mate”?

By: Ringo Bones 

During the cassette tapes heyday – in the early 1980s – “affordable” cassette tape decks were notorious for sounding “dull” when compared side-by-side with their upmarket counterparts, thus any after-market audio widget designed to improve the sound of your “affordable” cassette tape deck suddenly became consumer electronic best-sellers. But did the BBE Sonic Maximizer offer something better than other competing products? 

BBE, Barcus Berry Entertainment, Incorporated – which later became known as BBE Sound, Inc. is based in Huntington Beach, California that began operation around the middle of the 1980s. BBE Sonic Maximizers became widely used for audio recording, motion picture sound tracks, TV and radio broadcasting and motion picture sound systems, According to the audio processor’s creators, BBE Sonic Maximizers were primarily designed to improve the sonic clarity of virtually any reproduced sound by correcting / compensating for phase and amplitude distortions produced as your typical power amplifier drives a typical loudspeaker. 

Around 1986, BBE Sonic Maximizers first appeared widely as a stand alone unit to be connected between your source – be it a vinyl record turntable, cassette tape deck, VHS deck, hi-fi tuners and even CDs – and main preamplifier, though better results with cassette can be obtained if your tape deck’s peak output voltage is around 500-millivolts or louder. At the time, the best thing I notice about BBE Sonic Maximizers is that it can make a dull cassette recording sound better by subtly boosting the treble frequencies without appearing to add additional hiss, unlike using the tone controls or graphic equalizer in boosting the treble. 

By around 1991 to 1992, many musicians – like Skid Row, Megadeth, Queensryche amongst others – began using BBE Sonic Maximizers to enhance their recordings and the sound of their electric guitars and electric basses. But later on, “soulful” musicians started to dislike BBE because the BBE Sonic Maximizer box acted like a “heavy handed loudness control on steroids”. Boosting bass and treble frequencies tend to make the overall recording – or your musical instrument – sound as if the midrange frequencies were eliminated giving an impression of that hollow solid state sound that became unfashionable as the early 1990s single-ended triode vacuum tube amplifier craze went “viral”– quite far removed from what loud Marshall electric guitar amplifier playing is all about, which is tons and tons of gorgeous creamy midrange. Even upmarket Nakamichi DR series cassette tape deck owners steered away from BBE starting around 1994.

But to my ears at least, BBE Sonic Maximizers do serve a “niche purpose” where their treble boosting could prove useful. Like providing much needed treble boost to those dull prerecorded cassette tape albums from the 1980s where a “conventional” stand-alone noise / hiss reduction system will only make it duller, FM radio stations with excessive OPTIMOD compression usually sounds a little more dynamic when used with a BBE Sonic Maximizer and pre Burwen Bobcat enhancement era MP3 digital music download files. 

Woodles: The Bane of Cassette Tape Bass?

A “technical term” used to describe the lumpy low frequency response of cassette tape decks, can “woodles” be engineered out or reduced to nonexistence? 

By: Ringo Bones 

The term woodles was first coined by Steve Holding, a hi-fi audio equipment reviewer in Australian Hi-Fi magazine in which the term was used in the March 1998 issue. In this context, woodles means the irregular response in the bass or low frequency section of the audio frequency graph of a cassette tape deck under test. More popularly known in America as the “head contour effect” and is primarily caused by the bending of the tape as it travels around the record / replay head. 

A competently engineered cassette tape deck usually has woodles that deviates no more than plus or minus 2.5 dB below 50 Hz and plus and minus 1 dB above 50 Hz or better. A typical competently engineered modern cassette tape deck manufactured around 1990 onwards has a head contour effect that are usually below plus or minus 2.5 dB below 50 Hz due to modern record / replay head profiles and advances in record / replay head design. 

Historically, the Nakamichi DR series of cassette tape decks were known for having virtually nonexistent woodles or head contour problems since they’ve began making them by the start of the 1980s. It wasn’t until years later – as in the early 1990s – that other cassette tape deck manufacturers began making tape decks that can compete gamely with Nakamichi when it comes to engineering out the “woodle problem”. Like the Teac V-7010 cassette tape deck with a well set up head geometry virtually gave it a woddle free performance. And by the mid 1990s, Technics RS-AZ6 and Technics RS-AZ7 thin film head technology not only engineered out the head contour effect while pricing their cassette tape decks half that of a typical Nakamichi DR series cassette tape decks, but also gave the Technics series of thin film head technology equipped cassette tape decks CD-like bass and midrange without the use of proprietary Dolby S technology.