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The UP1, is a direct coupled low noise amplification design, capable of faithfully reproducing vinyl recordings in a way that has never before been available at this price point. MC/MM input stages are optimized for current noise and voltage noise respectively. Due to this ultra-low noise design, we do not know of any other unit which has an amplification selection of 80dB.
The minimal yet elegant design measuring 210mm wide by 95mm high by 183mm deep the UP1 sports an anodised fully CNC machined chassis that weighs 2.3kg with a separate power supply. Both the Phono chassis and PSU are fitted with anti-vibration feet.
The shielded toroidal transformer is housed in a separate steel chassis to remove any possibilty of compromising noise induced into the phono amplifier. Completely separate circuit boards are implemented for left and right audio channels, with a shared ultra-low noise regulated power supply that comprises 30,000uF of capacitance. The UP1 is equipped with one set of RCA input jacks and two pairs of output jacks. Both single ended and balanced outputs are catered for.
Each channel has two banks of DIP switches. One bank provides for: a large selection of input impedance values - 22, 30, 50, 100, 200, 430, 1k and 47k Ohms; additional capacitance; and Moving Magnet/Moving Coil selection. The second bank of switches sets the overall gain for your cartridge from 40db to 80dB in 5 dB steps. There is no cartridge that the UP1 will not be compatible with. For the more technically minded, details on the challenges presented to produce a high quality phono amplifier can be found here.
Output: 1 pair Unbalanced RCA (single ended) , 1 pair Balanced XLR
Input impedance:22 Ohm – 47 kOhm (selectable in 8 steps)
Output impedance: 50 ohm
Input capacitance (without additional switched capacitance): 100 pF
Input sensitivity: 200uV – 20 mV
Gain: 40 – 80 dB (2 VRMS output at 1 kHz)
THD 0.005 % (1 kHz)
MM cartridge: >107 dB A-weighted, input shorted
MC cartridge: > 85 dB A-weighted, input shorted
RIAA linearity: +/- 0.2 dB (20 Hz – 20 kHz)
Nominal output: 2 VRMS
Maximum output: 10.5 VRMS
Power consumption: 5 W
Dimensions: Preamplifier W 210 x D 183 x H 95 mm, 2.3 kg
Power Supply: W 114 x D 130 x H 63 mm, 1.25 kg
Shipping Weight: 5kg
The preamplifier remains the central control unit, the real heart of the hi-fi system. The preamplifier is irreplaceable for sonic reasons.
The Padma sports a fully CNC remote control and chassis of premium grade aluminium, ensuring an inert and stable base. Available in silver or black, its robust and sophisticated design ensures an efficient assembly and timeless appearance around an innovative design.
Since the release of the CP1 six years ago (2016) the entire wealth of OAD's experience was utilized to develop the new Padma Preamplifier. The Padma represents an uncompromising harmony of technology, styling and functionality, boasting ultimate performance and sound quality that ushers in a new era of the preamplifier.
In the CP1, the all discrete line stage which elevated single ended circuits to an unparalled level is further elevated by driving two such units in parallel, resulting in the Dual Balanced Topology which significantly improves electrical and sonic characteristics. Compared to the CP1 model, the already excellent noise level is reduced by a further 30 percent.
Volume knob mechanism by OAD Ultrafidelity
The volume has an attenuation range of 73 steps, 0.5dB per step. Balance range is +/-6dB (double the volume) in precisely 0.5dB steps. The volume control uses laser cut precision, lowest-noise and zero-induction resistors on a single die that have a zero temperature coefficient. Hence there is no possibility of change in resistance. The attenuator has a constant output impedance and extremely low Johnson noise that is consistent across all volume settings. Potentiometers and stepped attenuators cannot give superior right to left volume level matching that is critical when listening. Potentiometer based volume controls, such as even the best (Alps Blue Velvet) typically have something like +/-20% tolerance so the left to right channel matching can easily be out by as much as 2dB. The output impedance of such volume controls (and associated Johnson noise) also varies by where the volume control is set. For example, a 50K ohm volume control set to the middle will have 15 times or 23dB the noise of the Padma volume control. The Padma is immune to influences like mains quality and the choice of interconnects. The volume control directly controls the gain of the output stage via a digital link. This digital link allows the volume circuitry to be placed as close as possible to the input and output connectors to minimze the signal path for optimal purity. Accuracy, linearity and dynamic range of this arrangement is much greater than those of stepped attenuators and potentiometers. Operation is smooth and glitch free.
The entire path for all signals from the input connectors to the outputs is fully balanced. Audio purity is maximised by using minimal components in the signal path. Moreover, crosstalk is virtually eliminated by using a dual mono layout for left and right channels. Once again, only low-noise and zero-induction resistors are used.
Experience the ideal image for music playback that the Padma delivers. The music echoes throughout a space surrounded by silence.
The music signal does not pass through the volume sensor mechanism. It is just a position sensor to be able to set the desired volume. However, the look and feel of the volume knob is very important to audiophiles. A stepper motor delivers an elegant solution to volume control whilst still maintaining the timeless appearance and feel of a traditional knob.
Line Level Inputs: 3 Balanced and 6 Unbalanced
Line Level Outputs: 1 Balanced and 1 Unbalanced, 1 Balanced and 1 Unbalanced Home Theatre outputs
Overall Gain (dB): -63 to 9.7
Frequency Response (kHz): 0 - 650 -3dB @ 1.8VRMS Output
Maximum Output: >20V RMS
Signal to Noise Ratio (dB): >110dB A-weighted input shorted
Weight: 13 kg (28.7 lbs)
Shipping Weight: 14.6 kg (32.2 lbs)
Dimensions (WxHxD mm): 438 x 126 x 353 (17.2” x 4.96” x 13.9”)
Shipping Dimensions (HxWxD mm): 235 x 570 x 500 (9.3” x 22.5” x 19.7”)
The Vajra Class AB precision stereo power amplifier provides supreme driving performance. The Vajra will bring out the very best of any speaker, allowing you to enjoy never-before experienced soundscapes.
The Vajra, like the Padma, sports a fully CNC chassis of premium grade aluminium, ensuring an inert and stable base. Available in silver or black, its robust and sophisticated design ensures an efficient assembly and timeless appearance around an innovative design.
The Vajra uses the highest quality components available. Each component is tested for it's linearity. Linearity is a test of a component's input to output relationship. Only components with perfect linearity are used to ensure the highest accuracy and musicality.
Download Vajra User Manual: OAD Vajra Owner's Manual
Frequency Response (Hz) -3dB 0-100k
Power @ 8 Ohms 240VAC (W) 180
Power @ 4 Ohms 240VAC (W) 360
Gain (dB) 27
Sensitivity 4 V (BAL) 2 V (SE)
Input Impedance (Ohms) 24K (BAL) 12K (SE)
Damping factor >500
Noise Out <-100dBu(0-22kHz, Rs=50R)
THD 0.001% at 1kHz (100kHz Bandwidth)
Dimensions (WxHxD mm): 430 x 160 x 360