Neve Portico 5012 User Manual

INTRODUCTION

1

Thank you for your purchase of the 5012 Duo Mic Pre. Everyone at Rupert Neve Designs hope
you enjoy using this tool as much as we have enjoyed designing and building it. Please take note of
the following list of safety concerns and power requirements before the use of this or any Portico
Series

TM

product.

Safety

It’s usual to provide a list of “do’s and dont’s” under this heading but mostly these amount to
common sense issues. However here are some reminders:

The Portico 5012 dissipates about 35 watts, which means that it will get warm in use. The heat
generated is radiated through the case work and by convection through the ventilation holes.
Therefore the holes should not be covered or blocked. Portico modules may be stacked horizontally
on a desk top or vertically in a rack without heat problems. The anti-slip feet may be removed while
used in a rack, but should be retained for desktop use. Porticos should not be stacked immediately
above or adjacent to other equipment that gets hot. Also bear in mind that other equipment may
radiate strong hum fields which could spoil the performance of your Portico module.

Electronic equipment and liquids are not good friends. If any liquid was spilled such as soda,
coffee, alcoholic or other drink, the sugars and acids will have a very detrimental effect. Sugar
crystals act like little rectifiers and can produce noise, “crackles” etc. SWITCH OFF
IMMEDIATELY because once current starts to flow the mixture hardens, can get very hot (burnt
toffee!) and cause permanent and costly damage. Please contact support as soon as possible at
[e-mail] for resolution.

Don’t operate a Portico in the rain! If it gets wet and you suspect that good clean water may have
got in, Immediately unplug the unit, and remove it from the source of water. Take the cover and
knobs off by removing the 2 back-most screws on both sides only. The cover and front panel will
now slide forward and free of the unit. Gently wipe off any water that’s visible with a soft cloth.
Water may have percolated under the PCB and be hidden between the bottom cover and the PCB.
Use a hair drier to blow and dry out any residual moisture. leave the unit for a few hours to
completely dry out. If the moisture was due to CLEAN water, your Portico should be up and
running without any further problem.

Rear connecting cables can get very untidy when a number of Portico modules are stacked on
your bench. It’s a good idea to use cable ties to bunch the cords into a tidy form.

Don’t be tempted to operate a Portico with the cover removed. The cover provides magnetic
screening from hum and R.F. stray fields.

Power Requirements

Each Portico 5012 module has two built in DC to DC converters that provide +/– 17.5 VDC for
the amplifiers and + 48 VDC for microphone Phantom volts. The input is protected from reverse
polarity. The connector center pin must be positive.
The converters will work from any DC supply from 9 to 18 volts that is reasonably “clean”. Avoid
using a Power Outlet on the same circuit as air conditioning or other equipment that regularly
switches on and off. Unplug the Portico power unit(s) during a thunder storm or if it will be unused
for a long period.
When using a 12 volt battery, choose one that has enough capacity to power your Portico 5012 ­or your complete assembly of Portico modules – for the expected duration of your session. For
example, a 48 ampere-hour battery will power 8 Portico 5012 modules for 6 hours. *See power
requirement on specifications page.

FEATURE LIST

2

OUTPUT OUTPUT

B

INPUT

A

INPUTA BUSS B BUSS

MIC PRE

DUO

5012

POWER

+

12VDC

+48V Phantom Power

For appropriate microphones

Warning! Mute output prior to

engaging/disengaging Phantom power

Phase Invert

Flips phase

180 degrees

Mute

Main Output Mute

(Meter & Buss feed stay active)

To Buss

Sends signal

To Buss output

High Pass Filter

Fully variable from

20Hz to 250Hz

Mic Gain

Precision gain switch

(0 to +66dB in 6dB steps)

Level Meter

-30 dBu to +22 dBu

With reference to the output

5012 Duo Mic Pre - Front Panel

5012 Duo Mic Pre - Back Panel

DC input jack

2.1 x 5.5 x 9.5mm
Center Positive

SILK

Reduces negative feedback and

adjusts the frequency spectrum

to provide a very sweet

and musical performance.

High Pass Filter

Bypass / Engage

Power Switch

Disconnects supply

from internal power converters

Portico

TM

Bussing System

Connect as many units together as you'd

like to create your own mixes using

optional bussing modules

Top and bottom rows are normalled

together to allow for an IN / OUT / THRU

configuration

Output

Transformer coupled

Fully balanced and floating

1 = GND 2 = HOT 3 = COLD

Input

TLA Fully Balanced Input

1 = GND 2 = HOT 3 = COLD

5012 DUO MIC PRE

3

The PORTICO TM Series

The new RND “Portico”TM modular
preamplifiers and analogue audio
processors constitute a range of
building blocks that may be used
independently or in combination to
provide key elements that were
traditionally included in large format
Sound Control Consoles.

Your 5012 Duo Mic Pre

Microphone Input

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 permitting a full +26 dBu input signal to
be handled at unity gain without an input pad over the whole audio spectrum.

This 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.

A microphone is a voltage generator, not a power amplifier. Most microphones give their most
accurate performance when they are not loaded by the input impedance of a traditional
preamplifier.

Years ago transformer inputs with tubes were used for microphone preamps. It was convenient
to design the input for an impedance of 1,000 0r 1,200 ohms. Some microphones are still designed
to work well into a low load impedance. If the microphone has an inductive source (such as would
be the case if it has a transformer output) a low input impedance would cause the high frequencies
to roll off. This can be an advantage with some microphones!

If the microphone has an electronic circuit output, loading this with a low impedance will stress
the mic amplifier, causing slew rate and compression. A high input impedance allows the
microphone to “breathe” and give of its best, particularly advantageous with very high level
percussive sounds.

If it is desired, nevertheless, to present a lower input impedance to the microphone, we suggest
that an XLRF and XLRM assembly be made up with the desired resistor value connected between
pins 2 and 3. (If there is sufficient demand we may be offering this as a catalog item later)