JRDG Company Special – Criterion
2010 – approx 2013
approx 23.000 euro in 2012
The Criterion incorporates the most tried and proven concepts trailblazed by JRDG over the 25+ years of successfully developing the finest audio products available: battery power that provides the cleanest possible power source and isolation from the power grid, balanced circuitry, transformer coupling and much more. This time the batteries are incorporated in a much more user-friendly fashion: now they are user replaceable! Rowland’s latest products now feature a slightly curved frontpanel and are less wide (now 39,4 cm instead of 44,5 cm).
When I initially created this section I hadn’t directly compared it to the Coherence II but a friend had. It was at his place that I heard the Criterion for the first time but after he had sold his Coherence II. What I heard was a very fast, very dynamic and very open sound with still a hint of the famous Rowland air and fluidity. According to him, the Criterion is much faster than the Coherence II with a more foot-tapping quality and this could well be true since the Coherence II is indeed not the most forward or fast preamp around. But at the time I had doubts about whether or not the Criterion would also sound as luxuriously full and creamy as the Coherence II… I needn’t have worried.
Compared to Corus + PSU in Extensive Review
The IR remote controls are the same for the Corus and the Criterion.
Above: a VFD display is used, which I think is not the best choice due to this display type’s tendency to get dimmer with time. While legibility remains quite good for a long time, a few years of continued use already result in a somewhat cluttered look because the most used elements get dimmer first. A better option IMHO would have been to use an LCD display as used by Yamaha surround receivers. Not only will this type of display last longer than a VFD, it also has higher resolution and always retains its brightness and uniformity. The only thing that can fail on this kind of display is the light bulbs that light the display from behind but these are cheap and easy to replace. Ah well, this is the only downside that I can come up with for this otherwise stellar preamp.
User-replaceable D-Cell batteries. The two large screw terminals top right give easy access to the battery compartments.
Above: Pre amp part (with connections at the rear). Below: Power Supply part (with display and buttons)
Update 2012
Supposedly the Criterion may no longer be sold in the EU due to its battery powersupply. JRDG however aren’t resting on their laurels and are looking into other designs. We may see a new preamp fed by a super capacitor but for now, the Corus could be considered its replacement.
Update 2016
It seems that the Corus + PSU is positioned as the current reference. I have not heard anything about a new preamp to succeed the Corus. And indeed, since the Corus is essentially a Criterion sans battery power supply, the PSU should restore the balance.aa
Meanwhile I own a Criterion. Below are some pics to wet the appetite. An extensive review will follow!
Green Technology Product
How is Criterion a green technology product, and why is it important?
The Criterion reference preamplifier is a green technology product. Thanks to its highly regulated and very high speed switch mode power supply, its sophisticated DC power management system, and the extremely efficient TI Burr Brown OPA1632 fully differential I/O audio amplifier modules, Criterion draws only 15 Watts of power on idle, and a mere 50W at peak. It runs so cool to the touch that it can even be housed in a cabinet or custom media unit with no fear of overheating.
Criterion is completely Lead-free, and its battery technology is free of Cadmium metal, letting it conform to European (EU) environmental regulations.
Almost the entire preamplifier is made from recyclable materials, including its advanced ceramic electronics boards.
This is a time of rising energy costs across the World. Jeff Rowland is committed to creating and offering products that are not only supremely musical, but are also environmentally friendly, and help our customers to minimize their energy bills, while helping all of us to manage the finite energy resources of our planet.
BATTERY TYPE
The CRITERION PREAMPLIFIER has been designed to operate with industrial grade high current NiMH rechargeable D-cells with a capacity of 9 ampere hours. Replacement rechargeable D-cell batteries compatible with the CRITERION PREAMPLIFIER can be ordered directly from the JRDG factory.
WARNING:
NO OTHER BATTERY TYPES (CARBON ZINC, ALKALINE, NiCAD, LITHIUM) CAN BE USED IN THE CRITERION. ATTEMPTING TO DO SO MAY CAUSE FIRES, OR SEVERE DAMAGE TO THE PREAMPLIFIER. ANY DAMAGE TO THE CRITERION PREAMPLIFIER RESULTING FROM THE USE OF UNAPPROVED BATTERIES IS NOT COVERED BY THE JRDG WARRANTY.
BATTERY LIFE
The NiMH memory-free feature of the batteries, and the CRITERION PREAMPLIFIER’s advanced power management system, guarantee an extreme long life to the CRITERION PREAMPLIFIER’s batteries.(Up to 6 years under normal use).
REPLACING BATTERIES
Twist battery caps one quarter turn counter-clockwise and remove. Tilt the front of the CRITERION PREAMPLIFIER up so that three batteries slide out from each compartment. Place three new batteries into each compartment with positive (button end) facing the rear of the CRITERION PREAMPLIFIER. Install battery caps by pushing in and rotating one quarter turn clockwise.
Criterion Features
MACHINED ALUMINUM CHASSIS:
The preamplifier circuitry is housed inside twin ultra-low resonance, structurally rigid chassis precision-machined from solid ingots of aircraft grade 6061-T6 aluminum, completely sealed for trouble-free operation, yield maximum electrical/EMI/RF isolation.
FUNCTIONAL ISOLATION:
Power supplies and microprocessor-based system control circuits confined inside Control Chassis. Sensitive audio circuits isolated in separate Audio Chassis. Left and right channel circuits are further isolated into individual milled aluminum pockets in a true dual mono design for ultimate RF and EMI shielding.
FREE OF INTERNAL SIGNAL POLLUTION:
Control subsystem taken completely offline after each command execution to maximize sound purity. All signal switching relays are “latching” type which only draw current for a few milliseconds during the switching event then revert to a no current “off” state.
ADVANCED DC OPERATIONS:
NiMH field replaceable high capacity, industrial grade, rechargeable batteries provide the ultimate clean power source and absolute isolation from the power grid. AC power supply is taken offline during DC battery-based operations to isolate the CRITERION PREAMPLIFIER completely from residual mains grunge.
MULTI-REGULATED AC SMPS:
High speed regulated, low noise switch mode power supply (SMPS) developed for aerospace applications incorporates passive power factor correction (PFC) for sonic performance so pure and musical that is virtually invariant to different quality power cords. Power supply radiation is isolated by locating the power supply in it’s own milled pocket.
AUTOMATIC WORLDWIDE OPERATIONS:
Auto-sensing and auto-ranging SMPS provides optimum performance at any world-wide mains operating voltage between 85V and 265V.
CERAMIC CIRCUIT BOARDS:
All audio circuits are implemented on military-grade, multilayer, low dielectric constant, Rogers™ ceramic circuit board substrate for extremely low energy retention and absorption. Large low impedance ground planes for extended internal star-grounding. Newly developed ceramic capacitors replace conventional electrolytic type, resulting in power supply noise decoupling improvements by an order of magnitude (10X).
SHORTEST SIGNAL PATH:
Gain stages, based upon ultra-low noise differential balanced audio amplifiers, are implemented into the shortest signal path of any previous Rowland preamplifier. All signal paths are balanced from input to output for maximum noise rejection.
DUAL-ZONE PREAMPLIFICATION:
Separate 2nd gain stage for record outputs offers same circuitry as the primary signal path with independent volume control.
TRANSFORMER-COUPLED:
All inputs and outputs routed through professional grade Lundahl transformers for maximum common noise rejection, EMI immunity, and cross-component compatibility. Transformer coupling also ensures invariant gain for all balanced inputs and outputs. When used with input transformer equipped JRDG amplifiers a 140dB dynamic range interface can be achieved. All unbalanced inputs convert to balanced upon entering the preamp.
FLEXIBLE CONNECTIVITY:
6 inputs (4 XLR balanced, 2 RCA unbalanced); 4 main outputs (2 XLR balanced, 2 RCA unbalanced); 2 record outputs (1 XLR balanced, 1 RCA unbalanced); per channel.
INPUT GAIN OFFSETS:
Hi resolution independently programmable gain offset on each main input ranging from -20dB to +20dB in 0.5dB increments.
OUTPUT OFFSET:
High-resolution programmable gain offset on MAIN UNBALANCED OUTPUT 2 with 0.5dB resolution, independently adjustable relative to MAIN OUTPUT 1.
UNITY GAIN INPUTS:
Any main input can be configured as unity gain bypass for compatibility with theater processors.
PHASE INVERSION:
Independent signal phase inversion control on left and right channels for optimum speaker setup and system checks.
CHANNEL BALANCE:
Hi resolution (1.0dB) panning of stereophonic image (channel balance) for a maximum +/-20dB shift.
VFD:
Long life 32×320 pixel custom graphic vacuum fluorescent display (VFD) offers maximum resolution of display data for status indication.
HANDHELD REMOTE TRANSMITTER:
Highly ergonomic, custom handheld remote transmitter milled from aluminum billet supports complete system control and duplicates front panel operations.
REMOTE SENSOR:
Wired remote sensor milled from aluminum billet enables handheld remote transmitter operation while housing the preamplifier in closed cabinet enclosures.
PRECISION VOLUME ADJUSTMENTS:
Dual rate volume control allows precision level adjustments over nearly a 100 dB range. The volume control incorporates a permanently noiseless optical encoder that will always maintain its tactile feel, accuracy, and channel balance at all settings. The volume can be adjusted from 0dB to 99.5dB from the multi-role control knob on the front panel, as well as from the multi-function handheld remote transmitter. Rapid turns of the control knob adjust the volume by 1.5dB increments. Slow turns of the control allow for very fine adjustments by 0.5dB increments.
QUIET POWER-UP:
No turn-on or turn-off transients during intermittent power interruptions.
UPDATABLE SOFTWARE:
Internal port for software updates. Operational functions controllable via USB 2.0 port (rear panel) or 2.5 mm mini-jack (rear remote sensor).
CUSTOMIZATION:
Inputs can be custom named and set for different gain structures and automatically stored in internal memory
Criterion Technical Specifications
Overall Gain
Independently Programmable
0 to 20 dB on each input
Gain Range
99.5 dB, 199 Equal Increments
Gain Resolution
0.5 dB, +/- 0.03 dB Over Entire Range
Frequency Response
10 Hz – 300 kHz, -3 dB @ 8 ohms
Maximum Input Level
13.5 volts (RMS) @ 0 dB Gain
Maximum Output Level
13.5 volts (RMS)
THD + Noise
< .003% @ 2 volt (RMS) Output, 50 Hz – 20 kHz
Signal-to-Noise Ratio
> 100 dB
Common Mode Rejection Ratio
> 90 dB, 20 Hz – 20 kHz
Channel Separation
99.5 dB
Input Impedance
40k ohms Balanced or Unbalanced
Output Impedance
60 ohms Balanced or Unbalanced
Inputs
4 pair Balanced (XLR)
2 pair Unbalanced (RCA)
Outputs
2 pair Balanced (XLR)
2 pair Unbalanced (RCA) for Main Out
1 pair Balanced (XLR)
1 pair Unbalanced (RCA) for Record Out
Power Consumption
Min – 15 watts
Max – 50 watts depending on Battery Recharge Rate
Power Supply
Universal Voltage Input Power Supply with selectable Off-line NiMh Battery Power Supply and Charger
Display
320 x 32 dot Vacuum Fluorescent Display (VFD)
Preamplifier Weight
46 lbs / 21 kg
Overall Dimensions (H) x (W) x (D)
6.4” x 15.5” x 12.3” (162mm x 394mm x 311mm)
More Criteron
Compared to Corus + PSU in Extensive Review
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