Last Updated: August 2, 2017
The groove-type found on a Blue Note record offers a useful indication of the probable date of manufacture, and can help confirm or discount the status of a particular copy being an “original pressing”.
All Blue Note records manufactured in the 1950s and early 1960 have a deep groove on both sides of the label central area – a circular depression caused by the metal die used to hold pressing stampers in place. (This includes both first and subsequent re-pressings in that period)
In the latter part of 1960, new dies were introduced at the Plastylite pressing plant which behind left merely a single “step” – not a deep groove. The old DG and new non-DG dies were functionally interchangeable and coexisted for some four years, until the last of the old deep groove dies finally became worn out and discarded. All pressings thereafter were “no deep groove”.
During the transitional four years, original pressings appeared with every combination of die types: both DG, both non-DG, and DG only one side or the other. Various collector theories have been offered, about the use of old dies for re-pressings, new dies for new original pressings, but more likely it was simply arbitrary and random choice by the press operator. Nevertheless many original pressing have an historical established pattern.
The two types of groove are illustrated below:
Deep Groove (DG) on Side One and no Deep Groove on Side Two.
Many original pressings are undisputably associated with specific die pattern , until the arrival of new dies. When a record differs from the expected die type – no deep groove on a Fifties release, it is indicative of a later pressing. Only a handful of titles during the changeover late 1960 early 1961 (mostly between BN 4059-68) are known exceptions, with deep groove on one side and no deep groove on the other. In the years that followed, coinciding more or less with the introduction of the New York USA label, the first pressing of around 180 new titles by Blue Note all are no deep groove.
The definition of a “first pressing” is not as clear as some would like. Each time a batch of a particular record was pressed, or repressed, it was possible that a different combination of die types could occur when mounting the stampers. The recollection of a Plastylite press operator at that time was that records were pressed in small batches, with a half dozen presses in operation at the New Jersey plant, and that die selection was merely whatever came to hand when mounting stampers on the press. Some records may indeed had just one single pressing in a continuous run, which for small-selling titles and early 1500 series that was probably the case – and must be DG both sides. However there were re-pressings within the exclusively deep groove period, and as Blue Note sales volume increased, more copies pressed, the groove type and pressing status becomes less certain.
Beware the DG hype
Despite the ambiguity of “original” pressing, sellers shriek “DG!” and buyers foam at the mouth at the merest mention of deep groove, as if it were a badge of authenticity. Sometimes it is, sometimes it isn’t. Many earlier titles, pressed originally in relatively small numbers, original pressing DG both sides, were re-pressed between 1962-6 on the New York label, sometimes with deep groove on one side or both. As always with Blue Note, there are anomalies. Consult Fred Cohen’s book on identifying first pressings for specific details on all releases by Blue Note Records (note Fred has changed his judgement on a few since publication)
The presence or absence of deep groove is not a guarantee of superior audiophile performance, which is impacted by many other factors. Early pressings suffered more wear and tear over the years. Second and subsequent pressings by Plastylite still employed stampers derived from the same intermediate Van Gelder metalwork, and still sound distinctively “Blue Note”, and are often in better condition. However, sentiment still holds sway over many collectors: they want a piece of history, they want the original.
How vinyl records were made
To better understand the phenomenon of deep groove, see the LJC Slackers Guide to making records below and gain “Instant Expert” Status.
LJC ” Expert in Thirty Seconds” Slacker’s Guide to making records
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Step One – from music to stamper
Music is cut onto a master laquer by lathe. All that important information (catalogue number, master engineer signature) stamped or written is here on the runout area of the soft laquer. Mother/stamper positive/negative metal parts are created. The stamper central area is punched out. Printed paper labels are trimmed and center-punched ready for use.
Step Two – from stamper to finished record
Hot vinyl biscuit is sandwiched by labels, and mounted between a side A and side B stamper. Ensuring the labels were bone dry was critical at this point, as any moisture converts to steam during pressing. The press applies 100 tons pressure to the biscuit at a temperature near 200 C for 30 seconds, pressing the grooves from the stamper image into the vinyl. As the press lifts away from the newly pressed record (bottom right) you see the indentation left behind in the central label area by the metal dies holding the stampers in the press. Deep Groove, or not Deep Groove, this is where it all happened.
Congratulations.You are now a fully certified 30-second Vinyl Expert, saving nearly four minutes on watching the whole Discovery Channel You Tube.
Origins of Deep Groove
The deep groove has its origins in the pressing 78 r.p.m. records. The deep groove circle is just slightly smaller than the label of a 78, located within the label edge. As the recording and distribution medium switched from the breakable shellac 78 first to the 10″” and then 12″ unbreakable microgroove 33/1/3 LP, with its larger label, the deep groove was incorporated into the design of the new labels. Deep groove remained a feature during this period until pressing plants commissioning new presses to keep up with the expanding demand for vinyl records, phasing out the old presses, and with them, the older deep groove dies.
(Thanks to Cristian for the info on 78 rpm)
Other record labels and the Deep Groove
Deep groove impression is found on many other record labels such as Riverside and Contemporary pressed around this time. There is not as much documented about how these fit into the chronology of other pressing plant processes as there is for Blue Note and the Plastylite vinyl pressing plant. Eight different types of pressing die grooves from late Fifties to early sixties, ranging from Plastylite-like on Contemporary, to deep pudding bowl on Verve
An example of more PPM – pressing plant mayhem – is this interesting “anomaly” on the Prestige label (photo courtesy of Albert of Ohio) of Coltrane’s 1958 recording Black Pearls, first released by Prestige in August 1964. Stereo copies of the original pressing exist with different label designs, one with deep groove, another with no deep groove.
These differences are almost certainly attributed to the spread of manufacture to different plants, who may also have been tasked to print labels locally, hence variations in typesetting, pressing dies, even the use of “out of date” designs. Whilst Blue Note used just one plant, Plastylite (plus one known exception), it became common for some labels to press at two or three plant location, some times contracting pressing to independents for cost advantage.
Anyone with a more serious interest in the subject of pressing die indentations on record labels, I recommend to seek professional help. Or indeed amateur help, such as myself.