Plug-in equalisers that claim to emulate classic analogue designs can only ever be that — emulations, and depending on how well the algorithms are written, those emulations can be very successful or seriously disappointing. In the case of the Sony Oxford R3 EQ, however, the original was also a digital, DSP-hosted design (used in the Oxford digital console), so its transfer to a plug-in was relatively painless and didn't necessitate any emulation.
Essentially, the EQ comprises a five-band, fully parametric design plus switchable-slope, variable-frequency high and low-pass filters. The five-band EQ or the filter section may also be used alone to save on DSP power, in which case the unused sections are greyed out. Both mono and stereo operation are supported, making a total of six permutations. Additionally, there are four variants on the filter characteristics, the first having the least interaction between cut/boost and bandwidth. The remaining versions have different types of interaction built in to replicate the way some analogue equalisers work, and the high/low-pass filters also come in various flavours defined mainly by the filter overshoot response.
Oxford R3 runs on Pro Tools TDM and HD systems (with an optional GML 8200 emulation extra), or TC PowerCore cards running at least version 1.6 of the software. I tested the PowerCore version, which requires a Mac running OS 9.0.4 or higher or a PC running Windows 98SE, ME, 2000 or XP with an 800x600 minimum display resolution. The host software must be VST or MAS-compatible, and sample rates of up to 96kHz are supported.
Once the software is installed from the included CD-ROM, authorisation is via the Internet and follows the Pace challenge and response system, though it is slightly more involved insomuch as both a key file and an authorisation code are required. This authorises the software to run on one specific computer, which given the nature of the hardware, I feel is a little inappropriate. It would have been rather better if the authoriser created a version of the software that could be copied to any machine but which would only run with the specific card for which it was authorised.
Operating the plug-in is very simple and visual feedback is provided by an EQ curve display at the top of the plug-in window. Placing the pointer over any rotary control will indicate the current value and changes can be made by dragging the knob around in circles or, if the host software supports it, by using 'relative' circular motion or up/down motion. Each section can be bypassed separately and of course there's the usual master Bypass facility. User settings can be saved for future use and all controls may be automated if required.
The high/low-pass filters have slopes selectable from 6 to 36 dB/octave in 6dB/octave steps. Furthermore, two sets of EQ settings can be created and then selected using the A/B buttons to facilitate instant comparison. A clip Over warning shows if the EQ output has been clipped by applying excessive EQ boost to an already hot input signal. All the filter sections have a ±20dB range, with the five parametric bands covering the following ranges: 20 to 400 Hz, 30 to 600 Hz, 100Hz to 6kHz, 900Hz to 18kHz, and 2 to 20 kHz. The high/low-cut filters cover the ranges 20 to 500Hz and 1 to 20 kHz.
Whereas analogue circuitry would have a hard time delivering 20dB of EQ boost, Oxford EQ has a dynamic range of over 138dB (RMS unweighted) for each filter. Zipper noise is quoted as being below -95dB (peak) during the adjustment of any single control.
The number of plug-ins you can run on a PowerCore card at once depends on whether you use the filters and EQ together or not, and on the sample rate. For example, if you want to run both the filters and the EQ in stereo at 96kHz, you'll only get two instances up and running, whereas if you want mono EQ only or filter only at 44.1kHz, you can get up to 20 running.
I compared Oxford R3 with some of the better host-based equalisers I had at my disposal and found it to be somehow cleaner-sounding, and also capable of adding more high end without sounding harsh or processed. The type one EQ suited me best, but you have to be aware in this mode that changing a cut/boost value may also mean changing a Q value to compensate. In this respect it is not dissimilar in response to the original SSL 4000-series EQ, which was said by some to sound rather clinical. Type two is interesting in that it offers the same boost characteristics as type one, but has a constant-Q response in cut mode. This is the only non-symmetrical EQ on offer and it is as well to remember that because of this, you can't cancel out a boost by using an equal and opposite cut setting. This is said to be a popular EQ type for drums.
EQ type three exhibits a modest degree of Gain/Q interaction insomuch as the Q reduces as the gain increases, providing a fairly soft character. This EQ style follows that of some the older Neve types and the designers also claim a resemblance to the SSL G-series, while many popular outboard EQs share this dependency to some extent. Type four embodies a greater Gain/Q dependency, making it very gentle-sounding and well suited to the overall equalisation of mixed tracks. In truth, I found relatively little difference between the results that could be achieved by the four EQ types, but the different interaction between gain and bandwidth certainly gives them a different feel when in use. Because of this it's probably best to find a mode you like and then stick with it so that you can get to know it properly.
As with many PowerCore plug-ins, the latency increases noticeably when it is being used so my tactic is always to use plug-in delay compensation where provided and also to use Oxford EQ only when mixing, not while tracking. You can always use less sophisticated plug-ins to treat your monitor mix when tracking and then switch to the 'good stuff' when you come to mix. In all, Oxford R3 is definitely a cut above typical host-based equalisers, exhibiting both flexibility of control and a high degree of clarity. It doesn't sound as flatteringly musical as some analogue equalisers that colour the sound, but in the right hands, it can tackle most jobs without fuss, even where relatively large amounts of EQ boost are required. The adjustable high/low-pass filters are particularly useful, and on balance I'd say that if you're in the habit of using more than very minor amounts of EQ, then Oxford R3 would be a very useful addition to your plug-in armoury, both for mixing and mastering.
Pro Tools version £550, or £770 with GML option; PowerCore version £350. Prices include VAT.