Audio Database
System909
Commentary

Integrated amplifier with unique module design.

The System909 consists of a Power909 with a preamp and a digital processor.
Each operating part is designed as a module to ensure the complete operation of the power amp, preamp and digital processor components. In addition, the microprocessor protection module, which describes the status of each module, eliminates problems such as overload and overheating.
In addition, it was possible to cope with optional DSP and modules to be added in the future, and the structure was able to upgrade.


Preamplifier section

Equipped with Line 5 balanced inputs. These balanced inputs can be used with unbalanced inputs by using XLR adapters.
It also has balanced / unbalanced outputs for tape recording.

The Phono section is compatible with MC cartridges, and the load value of the cartridge can be adjusted in the range of 10 to 1k Ω by the DIP switch, and the input sensitivity can be adjusted in the range of 0.05 to 5 mv.

In order to maintain the dynamic range of the D/A converter, the signal path from the digital processor section bypasses the preamplification stage such as the CD/Tuner/Tape input.
The pre-amplifier stage of the line-level input is designed based on Blumester's unique X-AMP technology.

For volume adjustment, a high-precision stepped metal film resistor with an error of approximately 1% and a gold-plated relay switch are used.


Digital processor section

The digital processor's D/A converter consists of four 8 x oversampling 18-bit D/A converters, two for each channel.
This extends the benefits of balanced connectivity to the digital domain.

The digital processor is equipped with the digital input of Line 5, and has two outputs for DAT.
These inputs and outputs are designed in parallel and all digital inputs and outputs can be either optical or coaxial.

Three sampling frequencies, 32 kHz, 44.1 kHz and 48 kHz, are selected automatically depending on the source.

Equipped with an automatic de-emphasis function.
This function can be freely set in either digital or analog domain.

It is equipped with digital noise shaper and phase switching function.

Newly developed DSP can be installed as an optional circuit of the digital processor section.
Unlike conventional equalizers, this DSP can digitally process the sound characteristics of the playback system without adding channels or components. This DSP enables a variety of digital signal processing, including a compressor function that compresses the dynamic range to optimize the noise ratio of the listening room.


Other

A dedicated remote control unit is included.
The unit can be used to select the music source, adjust the volume, and select up to three types of DSP processing functions. The volume adjusted by this unit is digitally displayed on the entire body.

Model Rating
Type Pre-main amplifier
Digital Processor Unit
Digital input Line 5 (Optical / 75 Ω Coaxial)
Digital output 2 Systems (Optical / 75 Ω Coaxial)
Analog output Balance 1 System (2.5V/0dB)
Sampling frequency 32kHz/44.1kHz/48kHz
D/A converter 8 x Oversampling 18-bit D/A converter
(4 units)
Preamplifier Section
Input Sensitivity / Impedance Phono MC : 0.05 mV ~ 5mV/10 Ω ~ 1k Ω
Digital Module : 300 mV / Balanced 4.5k Ω ・ Unbalanced 10k Ω
CD, Tuner, Tape : 300 mv / Balanced 4.5k Ω ・ Unbalanced 10k Ω
Output Level / Impedance Tape out : 500 mV / balanced 0.8k Ω ・ unbalanced 1.6k Ω
Power Amplifier Unit
Output (stereo) 300W + 300W (8 Ω)
600W + 600W (4 Ω)
1,150W + 1,150W (2 Ω)
1,250W + 1,250W (1 ohm)
Frequency characteristic DC ~ 1.2 mhz -3dB
Rise time 1.4 μ sec (8 Ω)
Peak current 65A
Damping factor 1,000(1kHz)
Input Sensitivity / Impedance 670 mv / Balanced 5.7k Ω ・ Unbalanced 10k Ω
<General>
External dimensions Width 482x Height 530x Depth 482 mm
Weight 81kg