JRDG Company Special – Cadence MC phono stage
Retail price Cadence in 1998 in the Netherlands – 5490 euro
Retail price AC power supply in 1998 in the Netherlands – 1590 euro
Pictured on top of a Synergy 2i preamp. According to many people, myself included, this is one of the world’s best phono preamps. Sadly no longer made and rarely found on the second-hand market, this phono preamp also needs either a synergy or coherence to supply power or make use of the even more rare separate Cadence AC power supply.
Above: the Cadence together with the optionally available power supply. This supply looks precisely like the Synergy power supply, minus the display and related electronics. Inside it is almost identical.
Adding the optional power supply to a Cadence and Synergy preamp
This is something that is not absolutely necessary since the Synergy power supply has two power outlets to feed not only the Synergy preamp itself but also the Cadence. But the opportunity was there and I had a listen. It turned out that the addition of the extra power supply, feeding the Cadence, leaving the Synergy power supply to feed only the Synergy preamp, made for a big increase in sound quality. Even though the supply is similar to the one inside the Synergy power supply, soundwise it does make a large difference, making the sound more open, fuller and more colorful, but whether this is only due to the power supply itself or has to do with the DC cables, placement and power cables and where they plug into the extension block is the question.
Inside the Cadence
Above: one of the latest Cadence units inside.
Even though there was officially only one version, there is a difference throughout the serial numbers, not only in ingredients but also in sound. We have compared two Cadences, one fairly old and one off the last batch ever produced. The older one turned out to sound faster, more agile and more expressive, the latest model was warmer, fuller, wider in soundstage and more fluid. This sounds a lot like the differences between the Synergy 1 and 2i.
Above: This is the only occasion that I saw gold-plated Burr Brown opamps inside high-end audio equipment! These are the pick of the crop.
Older Cadence and newer Cadence comparison – Amp board
Here are 2 comparison pictures from the newer Cadence (top) and the older Cadence (bottom). Notice all the differences?
For starters, the white capacitors are different in size, although they have the same values. Furthermore, the little opamps next to the flatcable are on riser sockets (for easy replacement) in the new one and directly soldered in the older one.
Here are two more comparison pictures from the newer Cadence with serial P0348 which is one of the last produced (top) and the older Cadence with serial P0255 (bottom).
In the newer version, the input transformers are glued directly to the rear panel, in the older version they are squeezed in a tighter hole with a rubbery material in-between.
The audible results seem to contradict expectations. While you would assume rubber to sound rubbery and IC-risers to sound more metallic, the net effect is precisely the opposite! Welcome to the interesting world of JRDG!
Balanced XLR inputs and outputs
XLR to RCA adapters included for unbalanced (RCA type) phono interconnect cables.
Ideal matching to all moving coil phono cartridges with four (4) position gain and load switching capability. (low gain high load, high gain high load, low gain low load, and high gain low load)
High mass, non-resonant chassis, precision machined from 6061 aluminum plate, provides maximum isolation from distortion causing microphonics (vibration) in extremely low-level circuitry.
Operates in conjunction with the Synergy or Coherence Preamplifiers or with the optional Cadence AC Power Supply or BPS-1 Battery Power Supply.
Overall Gain (@ 1 kHz)
RIAA Accuracy ±.03 dB
20 Hz to 20 kHz
– 3 dB @ 0.5 Hz and 180 kHz
Common Mode Rejection Ratio
130 dB (@ 60 Hz)
Total Harmonic Distortion (THD)
< .015, 20 Hz to 20 kHz, 5 V output level
Output Noise (IEC A-Weighted)
Lo-Gain< 59 Microvolts
Hi-Gain < 60 Microvolts
Cartridge Loading Equivalent Resistance
Lo-Gain, Lo-Impedance 250 ohms
Lo-Gain, Hi-Impedance 400 ohms
Hi-Gain, Lo-Impedance 30 ohms
Hi-Gain, Hi-Impedance50 ohms
±12-14 Volts DC, 40 Milliamps
Balanced 1 per channel (XLR)
Unbalanced 1 Pair XLR to RCA adapters included
17.5 in (W) x 5.1 in (D) x 3.15 in (H) 44.5 cm (W) x 13.0 cm (D) x 8.0 cm (H)
27 lbs (12 kg)