Portico 5024 Quad Mic Pre

Four channels of legendary front-end tone.

Incorporating four channels of renowned preamplification, independent Silk controls, two channels of DI inputs, and an M-S Decoder into a 1U enclosure, the 5024 is a workhorse equipped to enhance the front end performance of any digital or analog recording system.

• 4-channel Mic Pre
• Based on the 5012 transformer and Class A circuirtry
• Phantom Power
• Hi-Z instrument inputs on Channel 1 and 2

Product Description
Incorporating four channels of renowned preamplification, independent silk controls, two channels of DI inputs, and an M-S Decoder into a 1U enclosure, the 5024 is a workhorse equipped to enhance the front end performance of any digital or analogue recording system. Each channel of the Portico 5024 is based around the custom transformers and class-A circuitry found in the best-selling 5012.

In addition to 72dB of gain, the 5024’s mic pres include individually selectable phase, mute, phantom power, a selectable frequency high pass filter, and the Silk circuit which yields the rich warmth and presence of the renowned classic designs. Channels 1 & 2 of the 5024 feature a high-Z input designed for instrument level sources. Channels 3 & 4 feature an M-S switch, which enables Mid-Side decoding without the use of multiple console channels.

Microphone Input
The microphone input is balanced but not floating, 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.

When the Phantom voltage is switched off, this input serves as a very high quality line input with an impedance of 10K Ohms.

Low Noise, Low Distortion Operation
Much care was given in designing the 5024 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 5024′s sweet, whisper-quiet performance.

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 5024 to work so unobtrusively within the context of a very high quality audio chain.

Features:
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.

M-S
The M-S button engages Mid-Side decoding on channels 3 & 4. Channel 3 level controls the mid signal, and channel 4 level controls the side signal.

Instrument Inputs
Balanced or unbalanced Hi-Z input for instruments using the Mic Pre’s gain circuitry.

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 below 30 or 90 Hz can be attenuated at 12dB / Octave, 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

Frequency Response:
Main Output, no load,
–3 dB @ 2 Hz
–3 dB @ 160 kHz

Noise:
Measured at Main Output, unweighted, 22Hz-22kHz,
Terminated 150 Ohms.
With gain at unity better than –92 dBu
With gain at 66 dB better than –56 dBu
Equivalent Input Noise better than –123 dBu

Gain:
Unity to +66dB in 6 dB steps,
Trim continuously adjustable from –6dB to +6dB
Line Input:
Trim continuously adjustable from –6dB to +6dB
Maximum Output Level:
Maximum output from 20 Hz to 40 kHz is +25 dBu.

Phantom Power:
48 Volts DC +/- 1%

Total Harmonic Distortion and Noise:
@ 1kHz, +20 dBu output: Better than 0.002%
As above, Silk Engaged: Better than 0.2% Second Harmonic
@ 20Hz, +20 dBu out Better than 0.004%
@ 20Hz, +20 dBu out Better than 0.020%
IM Distortion: Better than 0.002%
Slew rate Better than 4 V/uS
High Pass Filter:
Frequency: Selectable either 30Hz or 90Hz
Slope: 12 dB/Octave Bessel