"If you see a supposed 1977 pre-recorded cassette with any sort of reference to Dolby on it, you should be suspicious at the very least."
If you sneak a glance at the above photo, you'll see four audio cassettes, all of which purport to be from the 1970s. Three of them actually were produced in the 1970s, but one wasn't. Can you spot the later reproduction?…
The answer is: top left - Emerson Lake and Palmer - Works Volume II. Although the original album was released in 1977, the cassette shown actually hails from the second half of the 1980s. But how can you tell? All is about to be revealed…
BUY AUTHENTIC
When you're buying audio tapes secondhand, it can be extremely difficult to tell which ones come from the original 1970s production runs. And it's important to know, because this is a factor that can significantly affect the price. So in this post I'm going to discuss some of the tell-tale signs of reproduction 1970s cassettes. And since blank tapes are fairly easy to date by their design evolution - and there's stuff about that all over Tape Tardis - I'm going to be focusing specifically on the realm of pre-recorded media here.
One of the first things to take into account is that even though cassettes were a thing through the 1970s, albums were still often released on vinyl only. So the first question would be: was there even a tape version of a given LP available at all in the 1970s? Did the tape appear later, as was the case with the Jimi Hendrix Concerts cassette I recently looked at? Sometimes you'll be able to find out, sometimes you won't. But if not, fear not - there are other ways to spot a repro…
HISTORICAL KNOWLEDGE THAT SOUNDS THE ALARM
A good knowledge of what to expect from a real 1970s audio cassette is aided by an understanding of the history of consumer playback equipment.
Generally speaking, up until around 1976, the trend in consumer purchasing leaned towards portable devices. Devices you'd plonk onto a desk. Small, self-contained, and housing a single speaker of oldie-transistor quality (i.e. poor dynamic range with no significant bass or high treble response). Or dictaphone quality, as you might better know it.
This meant that most consumer playback was running in mono, and virtually none of the available equipment would have known what Dolby was - even if you screamed the word "DOLBY!!!" into the mini-mic 500 times and played it back at max volume.
1977 saw playback starting to transition towards high fidelity, stereo tape decks. But again, barely any of them had Dolby capability.
So if you see a supposed 1977 pre-recorded cassette with any sort of reference to Dolby on it, you should be suspicious at the very least. As you can see, our Emerson Lake and Palmer tape actually features a standalone Dolby logo - the face to face double "D" on the left of the casing. Hence, if someone were marketing that as a genuine '77 product, alarm bells should ring loud and clear.
In 1978, consumer cassette decks began to commonly feature Dolby noise reduction - a huge novelty selling point at that time. Few ordinary consumers knew what Dolby was back then, and it would have to be explained in the sales blurb for each product it appeared on.
So it's feasible that you'll see pre-recorded 1978 tapes with a reference to Dolby on them, but it wasn't the norm. And if the cassette has just the Dolby logo with no indication of what it means, it's very unlikely to be original, because how would a consumer interpret that logo? How would they know what it meant? Consumers had to be trained to associate the logo with the noise reduction standard, and that would take time.
Therefore, the original widespread incarnation of the Dolby logo was routinely accompanied by a "DOLBY SYSTEM" identifier, like the one seen on the 1981 Siouxsie tape above.
On the UK market, that "DOLBY SYSTEM" logo persisted up to and including the middle of the 1980s. I can't vouch for elsewhere. It's impossible to make categorical assertions about any cassette based on the Dolby identifier, and it appears there were some pre-records in the early 1980s that carried just the standalone, face to face "D" logo. Some pre-recorded tapes of the '80s, conversely, carried no Dolby logo at all.
DOLBY SUMMARY BY PERIOD
But broadly speaking, if a 1970s-dated pre-record displays a standalone Dolby logo with no reference to what it means, it was probably made in the 1980s - most typically post-1985. There are LOTS of exceptions to this, but my ballpark expectation would be…
1970-1978: No reference to Dolby on the cassette at all. And routinely nothing relating to the fidelity other than a mono or stereo designation.
1979: A minority of tapes referencing Dolby, sometimes in an unconventional way, but mostly with the logo plus a "DOLBY SYSTEM" identifier.
1980-1985: Increasing use of the logo plus a "DOLBY SYSTEM" identifier.
1986: Still a lot of pre-records bearing the logo plus "DOLBY SYSTEM". Another Siouxsie original above shows a 1986 implementation of this. Note the "C" chrome identifier on that tape too. There were some chrome pre-records in the 1970s, but that particular logo didn't appear until the 1980s - so again, if it's present on a '70s-dated tape, it's a later repro. Going forward from 1986, the standalone Dolby logo quickly became a standard, although "DOLBY SYSTEM" could still be found as late as the 1990s.
COPYRIGHT NOTICES
Another detective trick for identifying a repro as opposed to a genuine pre-recorded 1970s tape is to compare different periods of copyright notice. For example, anything bestowed with the Home Taping is Killing Music slogan is from the 1980s. It's beyond the scope of a modestly-sized blog post to provide specifics about other formats and wordings of notice, because they varied according to the record company. But the copyright notice was something that often would be updated as the dynamics of piracy and popular terminology changed.
CASING TYPE
Casings on pre-records were generally opaque until the second half of the 1980s. Paper labels are more common the further you go back in time, but there are lots of 1970s originals that have no labels, and have their info printed directly onto the opaque plastic.
The point at which you know you're not looking at a 1970s pre-record is when you see something like this…
That's the classic late 1980s style, with a transparent case, no labels, and dark grey interior insulation fully visible in front of the reels. The cassette is an original 1988 distribution of Voice of the Beehive's Let it Bee. The trend for pre-recorded tapes with this sort of appearance intensified into the 1990s, with paper labels becoming fewer and farther between. But again, it was only a trend. There are still lots of opaque cases from the 1990s.
Genuine 1970s pre-recorded audio cassettes can be expected to have opaque casing, and to carry no reference to Dolby. If they reference chromium dioxide media at all (and I have chrome 1970s tapes that don't - including the Atarah's Band Kit cassette in the opening photo), it will probably be a brief, written explanation, and not a logo.
To conclude, here's the kind of thing I'd expect to see from a pre-record made in the early to mid 1970s. There might be a "MONO" or a "STEREO" here or there, but overwhelmingly a complete absence of anything relating to the cassette's fidelity…
The 1980s was the decade of fidelity, and references to fidelity on a 1970s pre-record are the ultimate red flag. Certainly, any high tech references like XDR or HX Pro will eliminate the prospect of 1970s manufacture entirely.