Matej Isak of Mono and Stereo High-End magazine introduces two new Audio Research products: the CD9 and VSi75.
“Building on the success of the VSi60, which has won amplifier-of-the-year awards in at least four countries and continues to sell well, Audio Research is now pleased to introduce a vacuum tube integrated amplifier that takes power, performance, and esthetics to a much higher level, the VSi75.
The VSi75 does not replace the VSi60, it offers a significant step up in every meaningful way. The VSi75 provides 50% more power, with a muscular 75 watts per channel, from an all-silver chassis of the same dimensions as the VSi60. There is a natural anodized top plate through which the tubes project, like other VS-series amplifiers. Chassis corners are smooth and seamless, and the VSi75 has a new, low profile, anodized front panel containing six silver metal buttons for Power, Mute, Volume Up, Volume Down, Bias, and Input. A new LCD displays the Input, Volume, Stereo/Mono, and Operate/Mute. Numerals are green, with letters in white. And, the LCD will display the bias reading of each tube, making it easy to set the bias without a separate meter.
There is a silver perforated cover over the transformers and filter caps, extending to the back of the chassis. An optional cover for the tubes will be available at extra cost. The back of the VSi75 has five sets of single-ended RCA inputs, Tape Monitor (fixed level) RCA outputs, 0-4-8-ohm, gold-plated brass five-way speaker binding posts, and a 15-amp IEC connector for the supplied power cord. The metal remote that comes with the VSi75 controls all of the front panel functions, plus display brightness and tube hours. Something else to be appreciated is an entirely new volume control; although it has 103 visible steps like our other volume readouts, the gradation of the steps is much finer, especially at low levels.
The tube complement is the same as the latest VSi60, with four KT120 output tubes (one pair per channel) and two 6H30 driver tubes. Performance-wise, the VSi75 is in an entirely different league for a number of reasons. It has a new power transformer that was designed around the KT120 output tube. The VSi75’s wide bandwidth output transformers are the same as those in the remarkable Reference 75, and we also incorporate some key REF75 parts including proprietary coupling caps. And, we doubled the bulk power supply caps.
The resulting sound from these cumulative improvements is striking, with tremendous resolution of detail, silky and extended highs, surprising weight and authority, and the ability to develop an immense sound stage. The VSi75 sounds very much like the amp from which it borrows, the REF75, with an immediacy, delicacy and focus that are captivating. Couple it with a great source like the REFCD9, which it deserves, and you will be euphoric.
The VSi75 will only be available with a silver chassis and Natural anodized front panel, black will not be an option
Power Output: 75 watts per channel continuous from 20Hz to 20kHz. 1 kHz total harmonic distortion typically 1.5% at 75 watts, .05% at 1 watt.
Approximate actual power available at “clipping” 80 watts (1kHz). (Note that actual power output is dependent upon both line voltage and “condition” i.e.: if power line has high distortion, maximum power will be affected adversely, although from a listening standpoint this is not very critical.)
Power Bandwidth: (-3dB points) 12Hz to 70kHz.
Frequency Response: (-3dB points at 1 watt) 1.0Hz to 70 kHz.
Input Sensitivity: 0.55V RMS Single-ended for rated output. (32.5dB gain into 8 ohms.)
Input Impedance: 52.5K ohms Single-ended.
Inputs (5): 1, 2, 3, 4, 5 (Single Ended RCA connectors).
Maximum Input: 10V RMS (any input).
Output Polarity: Non-Inverting (any input).
Push Buttons: Volume up, Volume down (103 steps), Power, Input, Mute, Bias. All functions on IR remote control.
Output Taps: 8 ohms, 4 ohms.
Output Regulation: Approximately 2dB 8 ohm load to open circuit (Damping factor approximately 4).
Overall Negative Feedback: 4dB.
Slew Rate: 10 volts/microsecond.
Rise Time: 4 microseconds.
Hum & Noise: Less than 1.0 mV RMS -88dB below rated output (IHF weighted, Vol down).
Power Supplies: Electronically regulated Low and High voltage supplies for input stages. Automatic 40 sec. warm-up/brown- out mute.
Power Supply Energy Storage: Approximately 350 joules.
Power Requirements: 100-125VAC 60Hz (200-250VAC 50Hz) 400 watts at rated output, 600 watts maximum, 210 watts at “idle’: 1.0 watt power off.
Tubes Required: 2-Matched pair KT120-Power Output; 2 -6H30 driver.
Dimensions: Width 14.5” (36.8 cm) Height 9.25” (23.5 cm)
Depth 16.25” (41.3 cm) Rear connectors extend .88” beyond chassis.
Weight: 36.4 lbs. (16.5 kg) Net; 49.3 lbs. (22.4 kg) Shipping.
The Reference CD8 has been extremely popular, winning acclaim and awards internationally for its stellar performance since being introduced in November 2008. An engaging musical performance has kept its sales surprisingly strong, even in the face of new digital technologies. The fact is that lots of music lovers still embrace their compact disc collections and will not give them up.
After four years it is finally time to replace the REF CD8. People still want to play their CDs, but they also want to add other digital sources such as computer audio to their music systems, so we are introducing the REF CD9 CD-DAC. It combines the best of both, a super high-resolution compact disc player with a super high-resolution digital-to analog converter that is stunning in its musicality.
The REF CD9 incorporates four digital inputs: Asynchronous USB 2.0HS, AES/EBU, RCA, and Toslink. All inputs handle 24 bit / 192k resolution. As you would expect, the REF CD9 retains the Philips PRO2R transport, still the best dedicated CD mechanism available. It is simply unsurpassed for compact disc playback.
Benefitting from what we have learned in the development of the REF DAC and the DSPre, the REF CD9 utilizes quad 24-bit DACs running in mono mode, with dual master oscillators; one for 44.1/88.2/176.4 sample rates, the other for 48/96/192kHz sample rates. Sample rate conversion is selectable for all inputs, allowing playback in native resolution or via upsampling, including compact disc and—for the first time— the USB input. Additionally, there is a selectable digital filter, with either fast or slow rolloff. On the bench, the bandwidth of the REF CD9 is five times that of the CD8, with one tenth of the distortion, greater dynamic range, and it is also quieter.
Like the REF 5SE, REF PH2SE and REF DAC, the analog section is vacuum-tube, with four 6H30 dual-triodes, and there is vacuum-tube power-supply regulation featuring a 6550WE with a 6H30. The magic is continued.
The front panel has the familiar, dimmable CD display on the left side. On the right side there are three vertical LED displays indicating Sample rates (44.1-48-88.2-96-176.4- 192 top to bottom), Input (CD-RCA-USB-AES-TOS top to bottom), and Fast-Slow- Upsample-Power (top to bottom). Underneath the LED displays there are seven silver metal buttons for Power, Previous, Play, Next, Pause, Stop, and Input. Silver handles are standard with a natural front panel. Like its predecessor, the chassis and top cover are black, and the footprint remains the same. In addition to the digital inputs, the back panel includes Digital Outputs (AES/EBU and BNC), single-ended RCA and balanced XLR outputs, and a 15A IEC power connector. It comes with our new, metal remote.
Because it is functioning as separate DAC, Audio Research custom ASIO drivers must be installed in your computer for use with the USB 2.0HS input.
Sonically, the REF CD9 is in a new class, combining the magical musicality of tubes with new levels of transparency and aliveness. The REF CD9 sounds “faster” with greater transient speed, improved dynamics from top to bottom, much greater resolution of inner detail, with a focus and purity that is captivating. Rhythm, pace and timing are better than ever, something you must hear to appreciate.
Matej Isak. Mono and Stereo ultra high end audio magazine.