Primare Design Brief - PRE32 User Manual

Primare AB • Limstensgatan 7 • SE-21616 Limhamn • Sweden • Tel [phone] •

www.primare.net

September 2014

Design Brief - PRE32 pre-amplifier

7 pages

The PRE32 is an upgradable audiophile pre-amplifier designed to match the Primare A34.2 and
all Primare power amplifiers. It features the comprehensive OLED display and control
parameters established by the EISA award-winning I32 integrated amplifier. The PRE32 is
housed in a heavy gauge alloy steel chassis, and incorporates two pairs (L/R) of low-noise
balanced XLR inputs and 4 pairs of RCA inputs. In addition there are two pairs of RCA outputs
and a single pair of balanced XLR outputs, as well as a record output, RS232, trigger, IR and
RF inputs. MEDIA/streaming connections such as USB, iPod, LAN etc are available through the
modular MM30 media board, which may be enhanced with a high quality aptX Bluetooth
upgrade.

Audiophile Topology

All signal paths are fully balanced and as short as possible. All signal treatments (source selection,
volume and channel balance trims) are performed purely in the analogue domain. Unbalanced inputs
are converted to balanced signals by a conversion stage buffered by the excellent sounding Burr
Brown OPA2134 op-amps and fed to volume and balance controls employing closely matched
NJW1195 attenuators in a balanced configuration. Source selection is via high performance signal
relays.

Balanced signal transmission means that two identical signal lines are used to carry the same signal
with opposite phase. Any noise is common to both lines, is present in equal amounts and with identical
phase. At the receiving end a (differential) receiver retains the opposite phase signals (music) and
rejects the common phase ones (noise) leaving only the pure original signal. Balanced circuits
therefore keep the signal as free as possible from interference.

The four (L/R balanced) single-ended 16dB gain stage modules are fully separated. Each has its own
proprietary PCB, incorporating a custom designed copper heat sink, which also acts as a shield. The
gain module layout incorporates ultra-short signal paths and only the finest discrete components such
as MOSFET transistors, MELF resistors and polypropylene capacitors. Active, well-balanced current
sources are used instead of passive resistor networks.

The PRE32 is DC coupled from input to output. There are no capacitors in the signal path. Instead
active DC servos are used to compensate for any DC present, ensuring that the outputs are always
free from DC components.

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Primare AB • Limstensgatan 7 • SE-21616 Limhamn • Sweden • Tel [phone] •

www.primare.net

All the front panel control components are kept well separated from the analogue part of the PRE32 by

the front panel’s intuitive design: the electronics are placed between the front panel and the main steel

chassis.

Ultra low-power standby

The PRE32 incorporates a very low eco mode for standby. Power consumption is just 0.2W. In order
to minimise high frequency components originating from the standby power supply (high performance
switch-mode) when the PRE32 is in operation, the standby supply is switched off when the PRE32 is
powered up, and a discrete linear power supply consisting of only the finest discrete power supply
components and an R-core mains transformer, takes over.

Analogue and digital power supplies are kept well separated. For the analogue side a discrete ultra­fast voltage regulation circuit using discrete power transistors is used.

The power supply capacitor bank is large (25.000uF) and for lower ESR and best performance, is
divided between many smaller capacitors.

These measures have produced extremely good THD+N and S/N ratio figures for the PRE32.

Upgradeable Design

A media upgrade will be available, which offers up to 24 bit/192 kHz streaming of files from Internet,
NAS or PCs, as well as Internet radio content and also digital audio input from a range of devices
including CD players, smart phones, personal players, sat boxes etc.

MM30 media board

The MM30 multimedia upgrade module adapts the EISA award-winning I32 integrated amplifier and
the PRE32 stereo preamplifier for audiophile streaming, internet radio and gapless audio playback,
through integration with UPnP devices such as PC/Mac/NAS iPod®, iPad®, iPhone® or USB thumb
drive. It’s a genuine 24/192 DAC board including coax, TOSLINK, USB-A and USB-B inputs
(incorporating an asynchronous master clock for low jitter), and a high resolution (192 kHz) coax
output.

In addition there is a high quality easy-to-install aptX Bluetooth upgrade for the PRE32, which takes
the form of a small internal circuit board and external antenna (for improved reception), the threaded
antenna input replacing the DAB/FM terminal on the MM30 fascia.

Our definitions for File Based Audio:

Streaming: ‘live’ download for Internet radio and Music services like Spotify
and playing music over a network from NAS or PC

Playback of Audio files: Playing music files directly from laptop or PC over a USB-B connection. This
means using programs like iTunes (Amara) and JRIVER as user interface

Recommendations

 Use of a high quality wireless router
 Use of high quality CAT7 Cables
 Use of a switch between the Primare MM30, NP30 or PRE60 and computer or NAS
 Use of good quality files such as WAV, AIFF or FLAC-uncompressed
 Primare App is available for both iOS and Android. (iOS version supports Voice Over for

visually impaired users)

 For High Res streaming LAN is needed

Primare AB • Limstensgatan 7 • SE-21616 Limhamn • Sweden • Tel [phone] •

www.primare.net

 WLAN: 802.11b, g, n; 2.4 GHz band; WPA, WPA2 security – Ethernet: 10/100 MBit/s – DHCP

and AutoIP support

 Advantage of an asynchronous USB connection is that the clock, present in the DAC, controls

the flow of audio data from the computer to avoid the imprecise clock used in the computer.

 Please use a high quality USB-B cable for connection and make sure to check your audio

settings on your computer

 Also try the different USB connections on your laptop as they do sound different.
 Please make sure to download the PC audio driver from the SUPPORT section on our

website

 For playing music from PC over USB-B please download the Primare PCaudio driver from the

SUPPORT page from www.primare.net

 From MAC it will play automatically over USB-B will give best sound quality from Spotify

PREMIUM. (please set audio setting in Spotify to Extreme)

 Firmware updates can be done from the device's MENU or from Primare App

Supported Audio Formats

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