Rupert Neve Designs Portico 5015 Mic Pre/Compressor Module
The fully analog Rupert Neve Designs Portico 5015 Mic Pre/Compressor Module combines the outstanding sound quality expected from a Rupert Neve design with the total flexibility required by modern recording studios. The Portico 5015 features independent transformer-coupled mic preamp and compressor-limiter sections identical to those found in the Neve Designs 5012 and 5043 modules.

Available in both vertical and horizontal configurations, when used with the 5033 five band EQ it is possible to create a Portico channel strip with preamplification, dynamics processing and equalization. As an additional routing option, the microphone preamp output may be routed directly to the compressor section without patching by pressing the "To Compressor" switch.

Portico Series Awards:

Rupert Neve Designs has been honored with three TEC Awards since its inception in 2005. The Portico 5015 Mic Pre/Compressor won for achievement in the category of Mic Preamplifier Technology. The Portico 5042 "True Tape" Emulator (#482649) won for achievement in the category of Signal Processing Technology/Hardware. The 5088 Discrete Analogue Mixer won for achievement in the category of Large Format Console Technology.

Rupert Neve Designs received the Mix Certified Hit Award in 2006 for the 5088 Console and the Portico Range.

Rupert Neve Designs received the Future Music Platinum Award for the Portico Range in 2007.

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 Neve Portico 5015 mic preamp 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 Portico 5015 microphone preamp'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 VCA or voltage controlled amplifier (or attenuator) is used. There are many types of voltage control 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 VCA, 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 Rupert Neve Designs 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.

Feed-forward or Feedback?

The Portico 5043 provides a choice of feed-forward or feedback compression modes. The FB Button allows the user to switch between the two modes. If the VCA Control voltage is taken from the 5043's input, (before the VCA) the VCA knows right away that a gain change is required and there is almost immediate response. This is known, logically, as a feed-forward compressor.

If the VCA Control voltage is taken from the 5043's output, (after the VCA) it cannot act immediately on the VCA because it has already been modified by settings of the VCA and circuits through which it has passed. This is known as a feedback compressor. The two compression characteristics are quite different; there is more overshoot, and both the attack and recovery ramps are changed, providing the user with powerful choices. Almost all of Neve's earlier designs were feedback . They were more musical and sweeter than with feed-forward designs; however the feed-forward design provides greater accuracy.

Ratio and Threshold

Above a given threshold, signals are reduced by an adjustable amount ranging from 1:1, (which is linear, or no reduction at all), to more than 40:1 which is a very high ratio, equivalent to that of a Limiter. Ratio is sometimes referred to as slope because when depicted on a graph, the slope of the graph representing output versus input is what changes.

Ratio and threshold are closely interdependent. If a ratio as high as 40:1 has been set and the threshold is set at 0dBu, even when a massive signal of +40dBu (unlikely) is presented to the input, the output signal will only be +1dBu. Ratios as high as this would normally be set somewhere above 0dBu - say at +14 dBu, in order to prevent the output signal level exceeding just over +14dBu to protect, for example, a digital recorder. Similarly, if a ratio of 5:1 has been set, an input signal that is 10dB above threshold will only rise by 2dB above that threshold at the output.

The 5043's threshold control covers the range from below -30dB to +22dBu. When threshold is set at a low level with a fairly high ratio, the amount of gain reduction will be considerable and it may be necessary to use some gain after the compressor to restore the apparent signal level.

Attack Time

The attack time is the time taken for the compression circuits to start compressing. A long attack time allows short duration peaks to escape and go through uncompressed. This may cause overload on subsequent digital circuits. A very short attack time sounds unnatural and robs the signal of life by removing transients. Some transients are extremely fast and have little effect on the sound quality. Setting a long attack time often means that almost no gain reduction occurs because the transient is history (!) before compression has had time to operate. However, even the fastest circuits take time to operate, which means that there is always some overshoot. Small amounts of overshoot are musically desirable — there are exceptions, of course.

Setting the right values of release and attack is what compression is all about. Once the principles are understood a compressor/limiter such as the 5043 provides a powerful tool that actually appears to enhance the dynamic range of a recording and so provide greater musical enjoyment

The notes above explain how the 5043 handles signals of constant amplitude such as pure tones. Real program signals, however, are continually changing in level. The way in which a compressor deals with actual program material depends upon the magnitude and duration of peaks in the program level. If the release time is set to be very short, a short duration signal will be compressed but the gain will return to normal very quickly, giving a fluctuating and unnatural sound known as pumping when the background or other signals are forced up and down. The gain will also tend to follow the waveform of low frequency signals. Release time should be set long enough for the gain to remain reasonably constant between each bass note or between speech syllables.

Why Transformers?

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 20kHz 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. Since 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.

To correct these issues, 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 Mr. Neve's classic designs were 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, RF interference or other interactions, the connecting interfaces, grounding, levels, and impedances, must receive careful attention. Each Portico module is a complete integral signal processor that delivers its specified performance independently. This is why we use transformers.

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

Controls:

Silk:

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.

Level Meter:

-30 dBu to +22 dBu With reference to the output

Mute:

Mute cuts the output signal post meter and pre-buss output. Be sure to mute the outputs before engaging phantom power.

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 250Hz can be attenuated, leaving the range above this unaffected. This gets rid of building rumble, air handling motor hum etc.

Phantom Power:

Provides 48V phantom power to microphones

Buss Output:

The To Buss output is unbalanced and has a high impedance output. It is intended for use with the Portico Buss Amp/Monitoring modules. A TRS patch cord is used to connect the 5012.

Phase Invert: Flips the phase of an incoming source 180 degrees

Compression:

For signals below the threshold level that has been set, a compressor provides a linear path allowing signals to be amplified without the gain being adjusted in any way. When signals exceed the "threshold" level, the gain is reduced in a controlled manner that depends on the ratio that has been set.

Gain:

Gain range provided is from -6dB to +20dB. As already noted, when compression has taken place, it may be necessary to increase the overall gain to restore the apparent program level

Ratio:

Range from 1:1 to Limit (40:1)

Threshold:

Range from -30dBu to +20dBU

Attack time:

Range from 20mS to 75mS.

Release/recovery time:

Range of Release time is 100ms to 2.5 seconds.

Stereo operation:

When the Link button is engaged on two channels of Portico compressors connected via the link inputs that are set to approximately the same values, gain reduction on both channels will be the same to preserve stereo balance and center imaging.

Ducking:

When the link input is connected to another Portico series compressor with link engaged, the signal passing through one the compressors may be used to control the amplitude of the Portico compressor it's connected to.

Reduction meter:

An LED meter is provided that show gain reduction in the compressor. Reduction is calibrated in dB covering the range -1 to -22dBu, reading from right to left.


Rackmounting Porticos:
If you'd like to rackmount a single Portico, Neve offers the Half Rack Joining Kit (see #482654). Or to rackmount two Portico units, Neve offers its Horizontal Joining Kit (see #482653). Another option for mounting single half rack units is the Raxxess Universal Rack Shelf (see #421642).


Mr. Rupert Neve — the grandfather of pro audio

If anyone could be considered for the title, "Grandfather of Pro Audio," the first name that would leap to mind would be Mr. Rupert Neve.
Recognized as the developer of the modern mixing console, Rupert's handiwork is found in thousands of studios around the world.

In 1997, Rupert became one of a very few personal recipients of a Technical Grammy award. In awarding his Grammy, the Recording Academy acknowledged Rupert's profound impact on the industry:

Mr. Rupert Neve Grammy Honors

"For setting the standard for quality sound reproduction through his engineering and his innovative designs, which have made possible unparalleled advances in the quality of recorded sound; in recognition of his influence on a generation of audio designers; and for his dedication to purity of audio reproduction."

The morning following the amazing Grammy Awards ceremony in February 1997, Rupert and Evelyn Neve hired a stretch limo to take them to the airport. After all, for that day at least, Rupert was a star. Carrying the coveted Grammy Trophy in its distinctive blue Tiffany bag, they headed for security.

"What is this?" the security guard asked, puzzled by the strange image on her screen. "It's our Grammy," Rupert replied. The girl looked startled and in hushed tones said, "I'm so sorry sir. You'll have to check this. We can't carry ashes in the cabin."

"No, no, no," Rupert explained. "My Grammy - not Granny. Have a look if you like." She opened it up and for a moment security at the airport came to a standstill as girls screamed and all gazed in awe at the beautiful replica gramophone. It was almost the best moment of the whole proceeding.

Mix Magazine Hall of Fame

In 1989, Rupert was inducted into the Mix Magazine Tech Awards Hall of Fame in recognition of his lifetime contribution to excellence in recording and sound.

An Elite Fraternity

In 1999 he was honored as "Man of the Century" by Studio Sound magazine. At the turn of the century, Studio Sound conducted a survey inviting readers to vote for the Top Ten personalities of the industry in various disciplines. The first was Audio Personality.

It is Rupert's prized honor to have been selected by his peers in the Pro Audio business as number one Audio Personality of the 20th Century.

The Audio Century: Top Ten Audio Personalities of the 20th Century

1. Rupert Neve - champion of audio quality
2. Ray Dolby - household name
3. Sir George Martin - people's producer
4. Willi Studer - tape machine pioneer
5. Colin Saunders - founder of SSL
6. Alan Blumlein — inventor
7. Georg Neumann - microphone Designer
8. Michael Gerzon - mathematician
9. Valdemar Poulsen — inventor
10. Les Paul - guitars and multitracks