The “best of the classics” EQ
The 3-band, custom-tapped inductor EQ on the 5052 was inspired by RND’s favorite portions of Rupert’s vintage EQ designs. The low frequency band is primarily based on the 1064, which is renowned for its creamy, resonant bass. Unlike the 1064 however, the LF band on the 5052 can be used as either a shelf or a peak filter, adding punch, dimension, and immense control to your low end. The 5052’s inductor midrange band is based on his prized 1073 EQ, which is ideal for sweetening vocals and instruments while bringing them forward in a mix. Additionally, the mid frequency band’s proportional “Q” response makes it well-suited for minimizing problematic frequencies in a source. The 5052’s high frequency band is a hybrid vintage / modern design, blending inductor circuitry from the 1073 with capacitor-based topologies to achieve the vintage tones with enhanced control. As Rupert originally intended with his most prized classic designs, each EQ section uses low-feedback, class-A discrete electronics to prevent low-level artifacts and harshness from detracting from the tonal shaping. The EQ circuit itself, however, is a decidedly modern updated design using techniques and components that were simply not available 35 years ago, and should not be considered a “clone”.
Power, Connections and Mounting
The 5052 receives +/- 24V rails from an external DC power supply using a 4-pin connection. There are currently two options available: the RND 5-way brick supply and the RND 25-way 2U rack-mount supply. The back panel of the 5052 includes three XLR-F connections for Mic In, Line In, and EQ In, and two XLR-M connections for Mic Out and Main Out. The 5052 chassis is a “half-rack” format, and can be mounted in RND’s new 2 –way and 4-way vertical racks in addition to the existing 9-way racks and the 5088 penthouse.
A complete discussion on transformers is out of place at this point, but it is helpful to review some of the essentials where it will be seen that a design needs to be viewed as a whole, not simply from the point of view of a single component.
The fine subtleties of circuit design relating to sonic performance are gradually becoming more clearly understood. For example, research has shown conclusively that frequencies above 20 kHz affect the way in which humans perceive sound quality. But, long before scientific evidence emerged a substantial body of musicians and engineers knew that equipment with apparently the same technical measurements could sound very different.
Incredibly small amounts of musically dissonant odd harmonics have a disastrous effect on the sound quality. Extraneous noise or interference that finds its way into a signal path seriously impairs performance of the whole chain.
Many control rooms make use of outboard gear that is not well protected from external signals. Poor grounding of such equipment can be a serious problem. “Electronically balanced” circuits much used in modern equipment, can give very good measurements on the test bench but they do not provide adequate rejection of the stray fields found in every working environment.
Input and output circuits must be freed from ground dependence so that only the “wanted” signal enters and leaves the processing path. Transformers are the ideal solution. The sweet and silky sound of my classic old favorite consoles was achieved with big transistors and large high quality transformers. Rupert Neve Designs Portico modules achieve similar quality today without the bulk or the cost.
In order that modules can work together as would be expected (i.e. in a proprietary console configuration) without producing hum, R.F. interference, or other interactions, the connecting interfaces, grounding, levels and impedances must receive careful attention. Each of our Shelford modules is a complete integral signal processor that delivers its specified performance independently. This is one of the reasons we use transformers.