Get that great Neve sound with this cost effective Preamp/Compressor.

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.

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 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 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 Feed Back?
The Portico 5043 provides a choice of feed-forward or feed-back compression modes. The FB Button allows the user to switch between the two modes. If the V.C.A. Control voltage is taken from the 5043 input, (i.e. before the V.C.A.) the V.C.A. 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 V.C.A. Control voltage is taken from the 5043 output, (i.e. after the V.C.A.) it cannot act immediately on the V.C.A. because it has already been modified by settings of the V.C.A. and circuits through which it has passed. This is known as a "Feed-Back" 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 "Feed-Back". 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 inter-dependent. If a RATIO as high as 40:1 has been set, then if the THRESHOLD is set at 0 dBu, even when a massive signal of +40 dBu (unlikely!) is presented to the input, the output signal will only be +1 dBu. RATIOS as high as this would normally be set somewhere above 0 dBu - say at +14 dBu, in order to prevent the output signal level exceeding just over +14 dBu to protect, for example, a digital recorder. Similarly, if a RATIO of 5:1 has been set, an input signal which is 10dB above THRESHOLD will only rise by 2dB above that THRESHOLD at the output.

THRESHOLD control covers the Range from below -30dB to +22dBu. When THRESHOLD 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 un-natural 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 un-natural sound known as "Pumping" when the background, or other signals, are forced up and down. The gain will also tend to follow the wave form 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 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. 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 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 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:
Cuts of the output signal post metering 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 250 Hz 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 Inverts: 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 +20 dB. ?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 (i.e. 40:1)

Threshold:
Range from -30dBu to +20dBU

Attack time:
Range from 20 mS to 75 mS.

Release/recovery time:
Range of RELEASE time is 100 mS to 2.5 Seconds.

Stereo operation:
When the LINK Push-Button is engaged on two channels of Portico compressors connected via the link inputs 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 Push-Button is engaged and 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 its connected to.

Reduction meter:
A reduction LED METER is provided that show GAIN REDUCTION in the compressor. REDUCTION is calibrated in dB covering the range -1 to -22 dBu, reading from right to left.

Rupert Neve Designs Portico 5015 Mic Pre/Compressor Module Features:

Mic Preamp/Compressor Module
Individually Selectable Phase, Mute, Phantom Power And a fully Sweepable High Pass Filter
Ratio, Threshold, Attack, Release Gain Compressor controls
"Silk" Circuit Which Yields Rich Warmth And Presence
Provides 48v Phantom Power To Microphones
Compact Half Rack Module
Heavy Duty Construction

Rupert Neve Designs Portico 5015 Mic Pre/Compressor Module Specifications:

Preamp:
Input:
Balanced, using "Transformer-Like-Amplifier" (T.L.A.) with toroidal Common Mode Rejection Low Pass Filter that excludes frequencies above 150 kHz.
The T.L.A. is followed by an actual input transformer permitting a full +26 dBu input signal to be handled at unity gain without an input pad over the whole audio spectrum.
Combines the advantages of both an "Electronically Balanced" and true Transformer input.
When the Phantom voltage is disabled, this input serves as a very high quality Line Input.

Input Impedance: 10,000 Ohms + or 20%

Noise:
Measured at Main Output: Input terminated with 150 Ohms.
Measured over band limited 22Hz-22kHz, Unweighted:
With Gain at Unity: Better than 100 dBu;With Gain at 66 dB: Better than 62 dBu

Equivalent Input Noise (E.I.N.): Better than 128 dBu

Frequency Response: Main Output, no load:
@ 10 Hz, 0.2 dB
@ 160 kHz 3 dB

Buss Output @ 10 Hz: 0.2 dB @ 160 kHz 3 dB
High Pass Filter: Swept Frequency continuously variable from 20 Hz to 250 Hz.
Slope: 12 dB/Octave.

Gain: Switched Gain from Unity to +66dB in 6 dB steps.
"Trim": Continuously adjustable potentiometer from 6dB to +6dB with reference to setting on the Gain Switch.
Maximum Output Level: Balanced and Floating Transformer Output from 20 Hz to 40 kHz: +25 dBu. (Clips at just over +26 dBu)
Mute: Mutes Main Output only. (i.e. Monitor remains "Live")
Total Harmonic Distortion and Noise:

Main Output @ 1kHz, +20 dBu output level, no load: Better than 0.001%.
(No high order Harmonics)
Silk Engaged: Approximately 0.2% Second Harmonic
Main Output @ 20Hz, +20 dBu output level, no load: Better than 0.01%.
Buss Output @ 1kHz, +20 dBu output level, no load, measured at the output: Better than 0.002%.

SILK: The 5012 uses mainly single-sided amplifier circuitry that excludes any possibility of crossover distortion. The "SILK" button reduces negative fee
Crosstalk:
Measured Channel to Channel - Better than 90 dB @ 15kHz.
Phantom Power: +48 Volts DC &plusmin; 1%

Main Power Required: (From External Power Unit) Voltage Range, 9 to 18 Volts DC.

Current consumption:
@ 9VDC = 1.3 A typical
@12VDC = 1A typical
@15VDC= 800 mA typical
@18VDC= 650 mA typical

Compressor:
Gain Range: Continuously variable from 6 dB to +20 dB.
Threshold Range: Continuously variable from 36 dB to +22 dB.
Ratio Range: Continuously variable from 1.1:1 to "Limit" (40:1).
Attack Range: Continuously variable from 20mS to 75mS
Release Range: Continuously variable from 100mS to 2.5 Seconds.
FF/FB: Feed-Forward or Feed-Back VCA control.

S/C or LINK: Multiple 5043's may be daisy-chained via the rear panel jacks. When an individual channel is engaged, it's control voltage appears at the rear panel LINK jack. When both channels are engage
Maximum Output Level: Balanced and Floating Transformer Output
+25 dBu.

Total Harmonic Distortion and Noise: @ 1kHz, +20 dBu output level, no load.
Main Output, compressor bypassed - Better than 0.0006%.
Main Output, compressor engaged - Better than 0.02%
Noise: Measured at Main Output, un-weighted, 22Hz-22kHz, Terminated 40 Ohms.
With Gain at Unity, Compressor disengaged - Better than 103 dBu.
With Gain at Unity, Compressor engaged - Better than 92 dBu

Frequency Response: Main Output, Unity Gain
@ 18 Hz, 3 dB.
@ 150 kHz 3 dB.

Crosstalk: Measured Channel to Channel - Better than 80 dB @ 16kHz.
METERS A/B: Monitors INPUT LEVEL and GAIN REDUCTION of either Channel A or Channel B.

Power:
Voltage Range: 9 to 18 Volts DC, 9Watts
Connector: 5.5mm X 2.5mm DC jack, Center Positive
Current consumption:
@ 9VDC = 1.0 A typical
@12VDC = 730 mA typical
@15VDC= 570 mA typical
@18VDC= 480 mA typicalinput impedance
output impedance