JRDG Company Special – Model 525
Model 525 (2013-2017)
Retail price in 2013 in the Netherlands 5.400 euro
Retail price in 2016 in the Netherlands 5.700 euro
The 525 is an update to the model 201 and is a class D design capable of driving 250W into 8 ohms, and this can be taken to 1000W into 8 ohms when bridged. Interestingly, unlike most class D designs these aren’t based on the popular ICEpower modules but on new class D technology from Pascal in Copenhagen, Norway.
Extensive Review
Model 525 compared to Model 201 and Model 10
Model 525 Inside Pics
Model 525 Features
MACHINED ALUMINUM CHASSIS
Precision-machined chassis with integrated heatsinks, milled from a solid block of aircraft grade 6061-T6 aluminum, provides exceptional thermal heat transfer/dissipation, RFI/EMI shielding, and resonance control.
CERAMIC INPUT CIRCUIT BOARD
Input circuitry comprised of a precision instrumentation amplifier is implemented on mil-spec, low dielectric constant, Rogers™ ultra-rigid ceramic circuit board substrate for extremely low energy retention and absorption.
BALANCED TOPOLOGY
Inherent cancellation effects of balanced topology implemented throughout all power and input/output circuits ensures greatly reduced distortion and noise under dynamic signal conditions.
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.
THIN FILM RESISTORS
All resistors are low noise, 0.1% thin-film type for extremely low thermal noise which complement the low-noise characteristics of the active circuitry.
TEFLON COATED WIRES
All signal carrying input and output wires are teflon coated, also for low dielectric energy storage, further ensuring that each audio note reproduced naturally decays into the deeper silence of the music.
TRANSFORMER-COUPLING AND ISOLATION
Transformer coupled input circuitry provides universal component compatibility and virtually eliminate ground loop noise and RFI/EMI. Transformer coupling ensures identical amplifier overall gain when using unbalanced input adapters.
ACTIVE POWER FACTOR CORRECTION
Power Factor Correction (PFC) in the power supply reduces AC line harmonic noise pollution and increases AC line power utilization to 99%.
HIGH-EFFICIENCY SWITCH-MODE POWER SUPPLY
Highly efficient, compact, light weight, 1500 watt DC switch-mode power supply provides optimum voltage regulation for all circuits and operating conditions, and allows for quiet operation over a wide range of AC mains power sources.
PARALLEL BINDING POSTS
Dual CE approved speaker output terminals require no tools for secure, low resistance connections, and allow for easy bi-wiring applications.
FLEXIBLE 15 AMP AC POWER
15 Amp AC power inlet accepts a wide variety of after-market high-performance power cables.
FRONT PANEL STANDBY BUTTON
Illuminated front panel push-button switches the amplifier into standby mode (< 1 watt consumption).
REAR PANEL REMOTE JACK
12V 3.5mm jack on rear panel permits amplifier power on/standby switching in remote and home theater applications.
SELF-LEVELING SUPPORTS
Removable 3-point self-leveling Delron chassis supports provide high frequency mechanical noise isolation.
Model 525 Specifications
class D stereo/bridgeable amplifier
OUTPUT POWER:
250 watts @ 8 ohms/500 watts @
4 ohms 1000 watts @ 8 ohms BTL (bridge-tied load)
FREQUENCY RESPONSE:
5 Hz – 70 kHz, -3 dB
INPUT IMPEDANCE:
40k ohms
THD + NOISE:
< 0.05%, 20 Hz – 20 kHz
DAMPING FACTOR:
> 1000 @ 1 kHz
OVERALL GAIN:
26/32 dB BTL
AMPLIFIER WEIGHT:
14.5 lb / 6.6 kg
AMPLIFIER DIMENSIONS (H/W/D):
2.85″ x 8.4″ x 13″ 72mm x 213mm x 330mm
More Jeff Rowland
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Model 525 Extensive Review
Class AB vs Class D – Model 525 compared to Model 201, Model 10 and Model 6
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