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Dedicated Professionals striving to improve the World via Audio advancements​


An Introduction from Rupert Neve


I met Billy Stull soon after Evelyn and I came to live in Wimberley in 1994. He is a man of many interests but has always had a strong feel for high quality music recording.


Soon after he started a mastering studio I began to realize that Billy had "golden ears". But when he talked to me about what he wanted to do I thought he was joking. "A little bit of tape texture ? Some Classic flavor. Can we take the edge off this sound without touching the rest? How about getting some space around it? Let's move our seat to the back of the hall."


"That's not Pro Audio talk" I told him. But I got interested listening to what he was trying to do with his available gear and the Masterpiece started to evolve.


The MASTERPIECE is a two-channel collection of entirely analog processing modules, four modules for each channel and these are series connected on a "daisy chain" buss. The modules are fully enclosed (reminiscent of my original Console designs) and are fitted in a 6 U rack-mounting frame that carries the inter-connection back plane, the power supply and a fixed "master" module.


All the modules have identical rear connections. Their locations can be changed around as required, even "hot plugged". For example, the compressors can be inserted ahead of EQ etc.


Each individual module has an "IN" switch that lets that module be bypassed.



This unit is essential to the operation. It is fixed at the right hand side of the rack. It houses the main input and output circuits for the two channels: gain controls, a pair of bar-graph level meters, a pair of high and low pass filters and the IMAGE controls. At the bottom of the module are the two Master Bypass Push-Buttons, When pressed they turn red to remind you that although the meters and main Gain controls are active, all the processing is bypassed.


The main inputs to the MASTERPIECE are instrumentation amplifiers arranged in my well-known "Transformer-Like" configuration. These provide a 10K bridging input with very high impedance from each leg to ground and thus have good CMRR.


The main outputs make use of toroidal transformers that are a development of the original designs I used for the AIR Montserrat consoles. The audio path, without any processing switched in, is virtually distortion free right up to the clipping point at well over +26 dBu. The MASTERPIECE can be relied upon to interface freely with any other Pro Audio gear and is unmindful of whether the source or load is balanced or unbalanced.




One of the important features of the MASTERPIECE is the 3 band INPUT FILTER system that is used everywhere except, of course, on the Equalizer sections themselves.


A choice of High Pass, Band Pass and Low pass filters is available for insertion into the path of MASTERPIECE Processing blocks: TAPE TEXTURE, AUX SEND, VARI-PHASE, CLASSIC, and COMPRESSOR.

When all three INPUT FILTER Push-Buttons are pressed, the mixed outputs of the filters are combined and mixed to the signal return path.

The filter slope is 12 dB/Octave and the crossover frequencies are defined at - 3dB.


High Pass and Low Pass Filters produce opposite phase polarities. In order to obtain a flat frequency response over the whole audio band when they are mixed, it is necessary to invert the phase of the mid or Band Pass section. (Similar to the problem in loudspeaker crossover networks). So a Phase Invert Push-Button is provided for the Band Pass filter.


The effect of doing this can be heard on some program material - depends on whether the signal content tends towards a sine wave, as with a soprano voice or whether there is large harmonic content that spreads into adjacent frequently bands.


This phase reversal over a limited range of frequencies can produce some interesting spatial effects particularly when the IMAGING features are used.


A choice of two crossover frequencies is provided. The complementary LP and HP crossover filter frequencies are both shifted to produce an overall flat response regardless of the crossover frequency chosen.

From the Desk of Mr. Rupert Neve January, 2005


What is the difference in the EQ in the Masterpiece and your previous designs?
(a quote from Mr. Rupert Neve)

Equalizers... Books have been written about equalization, filters and tone controls or whatever they may be called. For many years I have designed and manufactured equipment using a large variety of circuits and each new product is gone through carefully, measuring and listening, to see if I can squeeze some small new advantage from a proven favorite! If I were to provide detailed circuits they would not necessarily sound like mine if built by others because, mainly, of the context in which they are used. I've seen more than one alleged "copy" which claims that it sounds the same as or better or ???


Well, this sounds trite, but I firmly believe that every designer is a creative artist and creates the best he can. Whether he acknowledges it or not, he has talent, like a painter or musician, that are gifts from his or her Creator. His (her) handwriting is on it. Indeed the very personality of the designer, is reflected in the design. If someone copies the design it is a forgery. What does that reflect? To the bank manager looking at a forged cheque, it is easily recognized as such. To the normal person who trusted in the value of that cheque, it is real until he tries to cash it and the bank informs him otherwise!


However, in recent years I have had the privilege of knowing Billy Stull. Billy has the most amazing gift of sound perception. Not only can he tell the difference between two very similar circuits, transformers or components, but he can articulate the difference in terms that are meaningful to a circuit designer. When Billy describes what he hears, I return to the design bench to adjust anything of which he may have been critical. In a nutshell, difference between new EQ and other circuits from my past are due to Billy's special gift.

Product Overview by Billy Stull


After many years and tons of mastering projects, I wished for more capabilities to deal with a diversity of incoming quality. The Masterpiece is a realization of my wish list and I am still blown away at the fortunate circumstances that allowed me to work with Mr. Neve to create this wonderful mastering and mixing instrument. It started out as a custom box for my own use, so there was no cost compromise on components. It is full of custom elements, hand work, old-school through-hole circuit assembly, and anything required for ultimate performance was designated. The only limitation was space and the unit is jam-packed with circuits and components. Mr. Neve commented that there is more circuitry designed in the Masterpiece than his previous large consoles. All this is costly, but It is what is required for the performance level that we have achieved. It wasn't a bunch of guys in a boardroom saying "What can we build cheaply and make a bunch of money?" This is the best that can be designed and built today and is made to take music to the next level, not please the bean counters. Stringing a bunch of boxes together has been the format for mixing and mastering, but now there is a system with one common power supply and an integrated work flow. However, the Masterpiece is not restricted and does allow for expansion by a carefully designed interface to other out-board gear with the bonus of being able to use that gear in a multiband application. We do sell the unit short-loaded if not all of the modules are required or as a way to get into the unit and purchase additional modules at a later time. A easy lease/purchase program is available as well.

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