Jeff Rowland Model 625s2 Stereo Power Amplifier

Jeff Rowland Model 625s2 Stereo Power Amplifier incorporates technical features, custom made design and advanced technologies to shield against noise interference, increase efficiency and provide a musical experience that is well balanced, transparent and dynamic.

Similar to the 825, it is built on a Roger's ceramic circuit board for lower dielectric absorption and low energy storage whilst enjoyed an increased power supply of 325 watts per channel.

Highly Efficient

The 625s2 stereo power amplifier incorporates a high-efficiency switch-mode power supply. It is ultra lightweight, and provides 1500 watts of DC switch-mode power supply and the best voltage regulation for all circuits and operating conditions, allowing for a very quiet operation over a wide range of AC mains power sources. Alongside this, the ceramic circuit boards used are ultra-rigid for lower dielectric absorption and energy retention.

Transformer-Coupling and Isolation

Transformer coupled input circuitry makes the 625s2 universally compatible with many components. It provides excellent rejection of common mode noise interference from the input source and virtually eliminates all RFI, EMI and ground loop noise. Transformer coupling ensures identical amplifier overall gain when using unbalanced inputs.

Low Distortion

Jeff Rowland's 625s2 Stereo power amplifier enjoys remarkably low distortion levels throughout the entire audio bandwidth. This is due to the input circuitry which incorporates an additional linear phase p2 pole filter which effectively reduces all unwanted signals from any source, such as DSD spurious noise. Alongside this, gold/Teflon/rhodium XLR input connectors and an advanced error-correction circuitry to provide additional solutions to decreasing distortion levels.

Key Features

- Machined Aluminium Chassis - Precision-machined chassis with integrated heat-sinks, milled from a solid block of aircraft grade aluminium, provides exceptional thermal heat transfer/dissipation, RFI/EMI shielding, and resonance control
- Composite Circuit Architecture - Unique composite circuit architecture incorporating separate Class AB voltage and current gain blocks with no overall negative feedback, delivers a sensuous grain-free musicality of unparalleled transparency and low level resolution.
- 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-Current Copper Bus-bars - High-current, dual polarity, ultra low impedance copper bus-bars distribute both power supply input current and signal output current, virtually eliminating intra-circuit EMI signal contamination, greatly reducing internal wiring, while increasing circuit board rigidity.
- 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.
- Power Factor Correction - Power Factor Correction (PFC) in the power supply reduces AC line harmonic noise pollution and increases AC line power utilisation to 99%.
- Dual-Position Speaker Terminals - Dual CE approved speaker output terminals, in both horizontal and vertical orientation, require no tools for secure, low resistance connections, and allow for easy bi-wiring applications.
- 20 amp AC Power - 20 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 theatre applications.
- Levelling Supports - Removable 3-point self-levelling Delron chassis supports provide high frequency mechanical noise isolation.