UNOFFICIAL JEFF ROWLAND INFO DATABASE
JRDG - The most beautiful amplifiers around
Aeris DAC
Introduced late 2011, begin 2012
Aeris with Corus preamp
Aeris with 625 power amp
Under the dac chip there are two Lundahl LL1588 transformers
TECHNICAL FEATURES
IsoSyncECS
Isolated Synchronous Error Correction System. Based upon an asynchronous buffer, voltage controlled crystal oscillators, and a 24 bit D/A converter – all under the precise control of an FPGA (Field Programmable Gate Array) running proprietary algorithms.
Bit Perfect and Virtually Jitter Free
Bit perfect conversion with total jitter output noise of less than 10 picoseconds RMS from any input – USB, TOSLINK, and SPDIF.
Multi-Stage Isolated Power Supply
Main power supply is isolated inside an external machined aluminum chassis. Eleven precision high-speed regulators provide low impedance and low noise “point of load” DC current to all analogue and digital circuits.
Isolated Audio and Digital Circuitry
Left and right channel audio output circuits, digital processing, and D/A conversion circuits are isolated within individual milled aluminum pockets resulting in exceptional EMI shielding, and thermal stabilization.
Volume Control
Wide range level control of outputs permit direct connection to power amplifiers.
Driver-Free Operation
The USB interface requires no additional drivers to install or maintain/update.
Cross-Platform
The USB interface is plug-n-play with all operating systems, including PC, Mac, or Linux.
Machined Aluminum Chassis
Precision-machined chassis milled from a solid block of aircraft grade 6061-T6 aluminum, provides exceptional thermal stability, RFI/EMI shielding, and resonance control.
6-Layer Circuit Boards
Multi-layer circuit boards provide extremely low impedance ground and power distribution for remarkably low digital noise contamination.
High-Precision Surface Mount Components
Extensive use of Lead (Pb)-free, low temperature coefficient, active and passive surface-mount components results in significantly smaller loop areas, reduced circuit capacitance and inductance, and introduces less noise than conventional leaded components.
Transformer Coupled Outputs
Transformer balanced XLR line outputs provide outstanding output common-mode noise rejection, eliminate potential ground loops, and ensure compatibility with other equipment.
Output Connectors
Rhodium / Teflon Cardas output connectors for both balanced and unbalanced outputs preserve maximum audio signal integrity.
Remote Control
Allows remote control of volume, mute, standby, and input selection.
SPECIFICATIONS
Inputs
1x USB Accepts up to 24 bit PCM at 44.1, 48, 88.2, and 96 kHz
1x Toslink Accepts up to 24 bit PCM from 11 - 192 kHz
2x SPDIF Accepts up to 24 bit PCM from 11 - 192 kHz
Outputs
1 pair balanced XLR / 1 pair unbalanced RCA 7 volts RMS max output level
Volume Control Dual-stage attenuation 70 dB range, plus 20 dB overdrive
Software/Drivers No special drivers necessary
USB interface is plug-n-play with all operating systems, including PC, Mac, or Linux.
Clocks (2X) 20 bit dynamic range Voltage Controlled Crystal Oscillators (VCXO), 44.1 kHz and 48 kHz < 1 picosecond RMS jitter
D/A Converter Differential output 352.8 kHz, 24 bit Digital Filter Finite Impulse Response (FIR) symetrical. Flat phase and group delay
THD+N Analogue outputs < 0.0006%
Output Impedance RCA / XLR 120 ohms
Analog Devices 1853 delta sigma 24 192 dac chip
Fairchild MOSFET's
Linear Technology Regulators
Xilinx Spartan FPGA DSP, Two gold crystal clocks above it
USB receiver from Texas Instruments - TAS1020B
Left - AD1895 192 kHZ Asynchronous Sample Rate Converter
Middle - Xilinx Flash for the Spartan FPGA chip
Right - AKM 4113 24192 SPDIF receiver
Moving into even greater detail
Aeris with PSU and 725 mono power amps
Below are some highly detailed Aeris inside photos grabbed from
 with Aeris 11-05-20_Highend_260 500pix.jpg)
The man himself with the Aeris
Loading
Streaming, USB, Firewire,
Computer Audio
Current and Classic CD players, Cables, Accessories and more
Galleries, timelines & interiors of fascinating classic equipment
Info, Tips, Tricks and Insights
How to optimise your system
Retail price - 11.500 euro
Jeff's first entry into the digital world - if you're not counting the ICE-power sidestep (which technically wasn't digital either). The Aeris is classic JRDG: a heavy solid block of aluminum with machined cavities for the electronics. As with recent preamps, the circuitboard doesn't hold many components yet the sound is typical Rowland: smooth, liquid, refined and detailed. But there's also a newfound beat in its step and dynamics aren't only good on a mirco-level but also on macro-level.
Find out all about classic and current Jeff Rowland equipment
IR receiver
I've compared the Aeris to the Meridian 818, PS Audio PWD MKII and PS Audio NuWaveDAC. The Aeris always wins. Even my beloved Mark Levinson no.390S CD player can't keep up.
Separately housed power supply. Inside are actually two supplies: one for analog and one for digital. Naturally the power supply is also machined from a single block of aluminium.
 DEF.jpg)