Cartec Audio EQP-1A
The original EQP-1A was a classic that inspired many imitations. Is Cartec’s re-take a legend reborn? John Pickford finds out.
Price: £1,992.00
Manufacturer: Cartec Audio
Website: http://www.cartecaudio.com
T his year, the EQP-1 will be 60 years old. But its manufacturer today, Cartec, was founded just two years ago. The original EQP-1 was launched in 1951 by US company Pulse Techniques of Teaneck, New Jersey (the town in which Les Paul built his first studio with an eight-track recorder). Pultec – as the company became known – comprised Ollie Summerland and Gene Shank, who between them handled all aspects of the business. Each unit was hand-made and, following an early modification, the Pultec EQP-1A remained in production for almost 30 years.
Fast-forward to 2009, when Liam Carter formed Cartec Audio in London and re-created the EQP-1A in fine detail – operationally, that is. The original Pultec was a 3U behemoth in blue. The new Cartec has been slimmed down to a more rack-friendly 2U design and the anodised brushed-aluminium front panel is finished in a shade of British racing green reminiscent of 60s MG sports cars. Front-panel legends are in a complimentary shade of yellow. Inside the box the components accurately emulate the original design, right down to the rectifying valve in the power supply (not found in other commercially available Pultec wannabes). And no, this isn’t the first Pultec copy – and we’re sure it won’t be the last – but while others take their inspiration from the original, the Cartec is the real deal – an authentic EQP-1A for the 21st century.
The front panel is laid out traditionally, albeit in a slightly more compact form. Cartec has even adopted the terms CPS (Cycles per Second) and KCS (Kilocycles per Second) to determine frequency rather than the more common Hz and kHz. For the sake of modernity, we’ll stick with the more familiar Hz and kHz for this review. At the low end, a stepped rotary switch provides four selectable frequencies at 20, 30, 60 and 100Hz. Two continuously variable pots allow for up to 13.5dB of shelf boost and 17.5dB of shelf attenuation respectively.
The high-end section works in a slightly different way. The larger of two switches facilitates the selection of seven frequencies at 3, 4, 5, 8, 10, 12 and 16kHz. The Boost pot provides up to 18dB of peak boost while the continuously variable Bandwidth pot determines the shape of the EQ curve, from narrow to broad. A smaller switch to the right allows for the selection of three frequencies at 5, 10 and 12kHz. The Attenuation pot controls these frequencies, providing up to 16dB of shelf cut. Equalisation is switched in or out via a chunky toggle switch. The back panel is simplicity itself: one XLR in, one XLR out and an IEC power socket.
Passive aggressive
The EQP-1A is a no-loss passive equalizer, which means that the signal level going in to it is reduced (insertion loss around 16dB) and then restored by an onboard amplifier. This means that there is no change in signal level when equalization is switched in or out. The amplifier stage remains in circuit when the EQ is bypassed and adds character to sounds passing through it, largely due to the valves driving the amp. Three valves are used: an EEC-82, an EEC-83 and a 6x4 rectifier. Liam Carter uses JJ valves, which, like all components in this unit, are chosen for performance.
Model EQ
The original Pultec EQP-1A has become a studio icon in the same league as Fairchild limiters or even the legendary Neumann U47 microphone. It is undoubtedly the most famous EQ ever made, which is why so many others have taken inspiration from the design – and why original examples in tip-top condition go for silly money. The EQP-1A has been used in all sorts of ways on many thousands of recordings. That’s the beauty of the design: it can be used to process single sources, groups of instruments or an entire mix, although you would need two for stereo, of course. During the US pop boom of the early 60s no self-respecting studio would be without one. Many had several. Tamla Motown made extensive use of them in their studios, so it could be said that the EQP-1A literally shaped the Motown sound. The engineers at the Tamla Studios in Detroit developed a method of carving out some midrange frequencies from the instrumental backing tracks, creating space for the vocals to sit nicely in the mix. A perfect pop technique – one which may well have been achieved by performing the ‘low-end trick’.
The low-end trick? Because the equalizer has separate controls to boost or attenuate the signal, it’s possible to boost and cut the selected low frequency simultaneously. Although this may sound counterintuitive, it works because the respective frequencies at which the boost and attenuation shelves are centred are not exactly the same. For example, if the frequency selected is 100Hz and both the boost and the Atten controls are turned to 7, the EQ curve displays what Cartec refers to as a ‘midrange droop’ centred on 1kHz. But if the Atten pot is returned to zero and the boost is still applied, the low-end frequencies remain the same but the droop disappears.
This method of simultaneously boosting and cutting the lows can be used to create some very useful EQ curves. It works on a wide range of sources from bass to acoustic guitar – not an instrument usually associated with bottom boost – and, used sparingly, is particularly good on male vocals, providing warmth to the lower registers without clogging up the critical mid band. Interestingly, the original Pultec manual advised that the Boost and Atten controls should never be used at the same time. It’s ironic, then, that the unit’s ability to do just that has helped it to earn its iconic status.
The Cartec isn’t just about the low end, though. The peaking top boost provides a useful range of frequencies which at the lower settings can add presence; if a narrower bandwidth is selected, a degree of edge is given to the source material. The higher settings add sparkle, space and air, particularly at broad bandwidth settings.
The high-frequency shelf cut can be used on its own or in conjunction with the Boost control, which is useful when you’re faced with several instruments that occupy similar places in the frequency spectrum (guitars and electric piano, for example, which may need some careful sculpting to remain distinct within the mix).
Testing times
We started testing by strapping the Cartec across a previously recorded vocal. A Neumann U67 had been used on that session and the signal had been sent to tape via a valve mic preamp. The low-end trick was employed, with both Boost and Atten pots set at around 3 and a frequency of 100Hz selected. We then boosted quite heavily at 8kHz with a fairly broad bandwidth. The vocal had sounded pretty good without EQ, but with the Cartec switched in it gained a mellow richness coupled with a glossy presence. The high end took on a glorious sheen that complimented the slightly dark nature of the Neumann.
After this we hooked up the EQ to an electric guitar track that had been recorded with a slight amount of compression. The part was quite complex, with choppy strumming punctuated by ringing power chords, but it just wasn’t cutting through in the mix. We applied a subtle degree of low-end roll-off at 60Hz and boosted at 3kHz with a medium bandwidth setting to add bite and emphasise the attack of the notes. To finish off the sound we gently attenuated the top end at 12kHz. Now the guitar came through clearly and found its correct place in the mix.
The final test was with a brass track comprising two trumpets and two trombones. The instruments had been recorded with an AKG C414 and double-tracked. We put the EQP-1A across one of the brass tracks and added generous boost at 16kHz with a broad bandwidth setting. Quite apart from the air that this gave to the signal, it seemed to make the ensemble sound more cohesive, uniting the players within a clearly outlined soundscape.
The EQP-1A has always been a very musical tool. It’s actually quite difficult to ruin your sound with it. What the Cartec (or any Pultec-inspired design) won’t do is perform surgical corrective EQ. For example, there’s no facility for pulling out vast amounts of 2kHz with a narrow Q from a problem signal. But that’s not what this unit is about. The Cartec EQP-1A is a creative EQ and improves almost any signal fed into it.
Some may balk at the prospect of shelling out almost £2,000 for a single channel of EQ, but consider this: with today’s almost unlimited track count available, the EQP-1A can be used to EQ a signal, then the equalized signal can be sent to a new track, freeing up the unit to be used again. This process can be repeated ad infinitum.
We are huge fans of the EQP-1A design and this new Cartec model is the most authentic replica available today. If you insist on absolute authenticity and require your EQP-1A to be big and blue and say Pultec on the front, then by all means go and spend £5,000 on an antique unit with similarly aged components. The alternative is to spend well under that amount for a brand-new one that will last a lifetime. It’s a no brainer. MTMThis year, the EQP-1 will be 60 years old. But its manufacturer today, Cartec, was founded just two years ago. The original EQP-1 was launched in 1951 by US company Pulse Techniques of Teaneck, New Jersey (the town in which Les Paul built his first studio with an eight track recorder). Pultec – as the company became known – comprised Ollie Summerland and Gene Shank, who between them handled all aspects of the business. Each unit was hand-made and, following an early modification, the Pultec EQP-1A remained in production for almost 30 years.
VERDICT
WHY BUY
+ Versatile creative tool
+ Quality build
+ Sounds fabulous
WALK ON BY
– Not as flexible as parametric or graphic equalizers for corrective EQ
The EQP-1A is as useful in today’s recording world as it was when it shaped the sound of pop music’s earliest years. Cartec’s stunning re-creation is the very best of its kind. Every studio should have one…
★★★★★★★★★★
Score: 10
This review first appeared in Music Tech Magazine issue 95
Filed under
Home,
Hardware,
Reviews
Sign in to download this article
New users, please register here
See also...
 MTM 111 |
FXpansion BFD Eco Review |
 MTM 108 |
Brainworx Vertigo VSC-2 Review |
|
 MTM 108 |
Yamaha 01V96i Review |
 MTM 107 |
25 Tips for Mix Processing |
|
MTM 107 |
Control for Live Performance |
 |
Music Tech Focus - Ableton Live 2012 |
|
 |
Music Tech Focus - Synthesis 2012 |
MTM 106 |
25 Pro Tips for Kick-starting Composition |
