Mic Pre/ Compressor Portico™ 5015 With independent transformer-coupled mic preamp and compressor-limiter sections identical to those found in the 5012 and 5043 modules, the fully analogue Portico 5015 combines the outstanding sound quality expected from a Rupert Neve design with the total flexibility required by modern recording studios. MICROPHONE Preamplifier The microphone input is balanced but not floating, being a variant of an instrumentation amplifer using a “Transformer-Like-Amplifier” (T.L.A.) configuration with a toroidal Common Mode Rejection Low Pass Filter that excludes frequencies above 150 kHz. The T.L.A. is followed by an actual input transformer designed by Mr. Neve that permits a full +25 dBu input signal to be handled at unity gain without an input pad over the whole audio spectrum. This innovative solution combines the advantages of both an “Electronically Balanced” and true transformer input. In addition to the 72 dB of gain, the 5015 mic pre includes individually selectable phase, mute, phantom power, a swept high pass filter from 20-250 Hz, and the “Silk” circuit which yields the rich warmth and presence of the renowned classic designs. The Compressor Section The 5015’s compressor has fully variable threshold, ratio, attack, release and makeup gain with two selectable VCA modes that provide for exceptional control of any source material. How it Works In order to control gain, a V.C.A. or Voltage Controlled Amplifier (or Attenuator) is used. There are many types of V.C. including the use of tubes, discrete and integrated solid state circuits and naturally non-linear devices, each one having its characteristic behavior that reflects sonically on the final performance, and gives it a character or signature that can be musically attractive or not! The Portico 5043 makes use of a very accurate, low noise, low distortion V.C.A. having, essentially, no signature of its own. A part of the audio signal is rectified and smoothed to produce a suitable control voltage for the V.C.A. which has to respond very quickly and have low distortion. If the response is too fast, low frequency signals will themselves, be gain controlled! If the response is too slow, the signal will overshoot and the first few cycles will not get compressed. The speed and accuracy of the response, known as the “attack”, and the time frame that gain remains under the initial control, known as “release” or “recovery” and plays a large part in the way a compressor sounds. All Portico modules use input and output transformers and, almost entirely discrete component amplifiers. In fact the Line amplifiers on their own, inserted into the signal chain, are capable of enhancing the sonic quality of many signal sources, especially those of digital origin. These are some of the factors that enable, the Portico 5043, to work so unobtrusively within the context of a very high quality audio chain. SILK Much could be written about this feature, suffice to say, that it gives a subtle option to enhance sound quality in the direction of vintage modules. The Silk button reduces negative feedback and adjusts the frequency spectrum to provide a very sweet and musical performance. We suggest you try it and make your own judgment. High Pass Filter The High pass filter is a valuable aid in any signal chain but particularly so in a microphone preamplifier. Signals between 20 and 250 Hz can be attenuated, leaving the range above this unaffected. This gets rid of building rumble, air handling motor hum etc. LOW NOISE, LOW DISTORTION OPERATION Much care was given in designing the 5015 to produce as little noise and non-harmonic distortion as possible. Carefully implemented signal paths and Class A operation are a large part of the 5015’s sweet, whisper quiet performance. For more information, go to Mr. Rupert Neve’s Design Notes Phantom Power Provides 48V phantom power to microphones FURTHER INFORMATION If you need any product information, or advice, or just the name of a dealer in your area who we recommend, please feel free to contact us anytime and we'll be glad to help out. For further information please email: sales@sonic-distribution.com or call the Main Office: (0845 500 2 500) anytime Monday to Friday 9.30-6.00pm Copyright Sonic Distribution LTD. 2007 All Trademarks and ownership rights respected.