CH Precision Releases The P1.5 And L1.5 Preamplifiers

All Image Credit: CH Precision

Swiss high-end audio manufacturer CH Precision has released two new preamplifiers, the P1.5 phono stage and L1.5 line preamplifier. These new models are said to bring technologies developed for their reference 10 Series into slightly more accessible price range. Pricing; £34,200, $39,500 or €41,500 each.  The new models offer upgraded circuitry that has been developed to lower noise and improve performance, along with greater compatibility with other components. Existing owners haven’t been left out either, with CH Precision offering an upgrade path rather than requiring owners to purchase an entirely new unit.

The new design continues CH Precision’s modular approach to high-end audio, drawing on the engineering knowledge developed for the more expensive P10 phono stage. The P1.5 uses a three-stage amplification architecture with passive equalisation between the gain stages. CH Precision claims that this revised circuitry improves equalisation accuracy while significantly lowering the noise floor. When compared with its predecessor, the P1.5 is claimed to reduce equivalent input noise by 6dB on its current-sensing moving-coil inputs and 4dB on its voltage-sensing input. Available gain headroom has also increased by 6dB and 5dB, respectively, providing improved flexibility for a wider range of cartridges.

The two current-sensing inputs accommodate low-impedance moving-coil (MC) cartridges, a third voltage-sensing input supports moving-magnet (MM) and moving-coil (MC) designs. The latter offering more than 400 selectable resistance values ranging from 20 ohms to 70K ohms, enabling very precise cartridge loading. Support has also been expanded for various record equalisation curves. While standard RIAA equalisation is the default, an optional module adds playback curves from labels including; Columbia, Decca, EMI, Philips and Capitol. While a A 50 kHz Neumann pole and second-order 7 Hz anti-rumble filter can be engaged independently with any EQ curve, adding flexibility without sacrificing precision. CH Precision has also retained its software-assisted Gain Wizard and Loading Wizard, which help users select optimum settings for individual cartridges.

Dedicated mono playback configurations for two-coil mono, and single-coil mono cartridges are also provided, supporting owners with specialist cartridges and vintage mono pressings. While system control is available through the front-panel controls, supplied remote or CH Precision’s control applications.

Rear panel signal connectivity includes; 2 x stereo RCA/XLR current sensing inputs, 1 x stereo RCA/XLR MM/MC input, 1 x stereo RCA/XLR line level out. Other connections include 1 x RJ45 Ethernet, 1 x external DC power and signal and chassis grounding.

The L1.5 also features four balanced XLR plus two unbalanced RCA inputs per channel, with digital control circuitry galvanically isolated from the analogue signal path. The preamplifier is fully DC-coupled, with no coupling capacitors in the signal path, incorporating technologies developed for CH Precision’s reference L10, including new discrete diamond input buffers designed to improve electrical and thermal stability, Class-A amplification throughout, and refined power regulation.

CH Precision says the changes improve signal integrity while minimising unwanted noise and distortion. Volume adjustment is handled by a fully differential 20-bit R-2R resistor network operating entirely in the analogue domain. It provides attenuation from -99.5dB to 0dB in precise 0.5dB increments, with selectable active gain settings of 0dB, +6dB, +12dB and +18dB.

Operation is available through the front-panel controls, supplied remote or CH Precision’s control applications.

Rear panel signal connectivity includes; 2 x stereo RCA line level inputs, 4 x stereo XLRline level  inputs, 1 x stereo RCA and 2 x stereo XLR stereo line level outputs. Other connections include 1 x RJ45 Ethernet, 1 x external DC power and signal and chassis grounding.

Finally, both preamplifiers remain compatible with the company’s optional X1 external power supply, which relocates critical power supply circuitry into a separate chassis to reduce electrical interference within the audio components.

Specifications:

P1.5

• General
  • Type: Phono preamplifier
  • Options: EQ curves module pair to play EMI, Columbia (LP), Decca (London), DGG (Teldec), NARTB (NAB), Capitol/AES and Philips records
  • Upgrade path: X1 external power supply
  • Color: Silver (standard), Anthracite or Champagne (option)
  • Dimensions: 440 x 440 x 133 mm (W x D x H)
  • Weight: 20kg
  • Operating conditions: 5°C<T<35°C, 5%<humidity<85% no condensation
  • Power supply: Selectable 100V, 115V or 230V AC, 47Hz to 63Hz
  • Power consumption:<0.5W standby, 50W nominal​
• User interface
  • Display: 800 x 480 pixels, 24 bit RGB AMOLED
  • Control: 5-button interface, Infrared remote control, Android and iOS apps
  • Firmware update: via USB flash drive or the Internet​
• Analog inputs
  • Type (each available on both XLR and RCA connectors):
    • 2x MC current-sensing inputs (for low internal impedance – almost only MC –  cartridges)
    • 1x MM/MC voltage-sensing inputs (for MM, step-up transformer couple MC or high internal impedance high level MC cartridges)
  • Impedance:
    • MC: < 100mΩ, virtual ground
    • MM/MC: User selectable, 20Ω to 70kΩ
  • Gain (at 1kHz, on single-ended output – balanced output is 6dB more):
    • MC: +56 dB to +77 dB in 3 dB steps (10Ω internal impedance cartridge)
    • MM/MC: +42 dB to +75 dB in 3 dB steps
  • Equivalent input noise (20Hz-20kHz, unweighted):
    • MC: < -143 dBu (< -144 dBu with X1) / 1Ω termination
    • MM/MC: < -138 dBu (< -139 dBu with X1, < -142 dBu if G>+53dB with X1) / 1Ω termination
  • Playback EQ curve accuracy: +/- 0.1dB
• Analog outputs
  • Type: 1x balanced XLR, 1x single-ended RCA, per channel
  • Level: 8VRMS maximum (balanced), 4VRMS maximum (single-ended)
  • Total Harmonic Distortion + Noise: < 0.002%, MM/MC voltage input, gain < 55dB
  • unmeasurable (below noise floor) for MM/MC voltage input, gain > 55dB
  • unmeasurable (below noise floor) for MC current input, any gain

L1.5

• General
  • Type: Line preamplifier
  • Upgrade path: X1 External Power Supply
  • Color: Silver standard; Anthracite or Champagne optional
  • Dimensions: 440 × 440 × 133 mm (W × D × H)
  • Weight: 20 kg
  • Operating conditions: 5°C < T < 35°C; 5% < humidity < 85%, non-condensing
  • Power supply: Selectable 100 V, 115 V, or 230 V AC; 47 Hz to 63 Hz
  • Power consumption: <0.5 W standby; 55 W nominal
• User interface
  • Display: 800 × 480 pixels, 24-bit RGB AMOLED
  • Control: Dual-concentric encoder with push function; infrared remote control; Android and iOS apps
  • Firmware update: USB flash drive or Internet
• Analog input
  • Type: 4 × balanced XLR and 2 × single-ended RCA per channel
  • Input impedance:
    • Balanced: 94 kΩ or 600 Ω
    • Single-ended: 47 kΩ or 300 Ω
  • Maximum input level:
    • Balanced: 16 VRMS
    • Single-ended: 8 VRMS
• Volume and Gain
  • Attenuation range: –99.5 dB to 0 dB
  • Adjustment resolution: 0.5 dB
  • Active-gain settings: 0 dB, +6 dB, +12 dB, or +18 dB
  • Total operating range: –99.5 dB to +18 dB
• Analog Output
  • Type: 2 × balanced XLR and 1 × single-ended RCA per channel
  • Output impedance:
    • Balanced: 2 × 30 Ω
    • Single-ended: 50 Ω
  • Maximum output level:
    • Balanced: 12 VRMS
    • Single-ended: 6 VRMS
  • Bandwidth: DC to >700 kHz, –3 dB; volume at 0 dB; 0 dBu input signal
  • Total Harmonic Distortion + Noise: <0.0008% (@ 22Hz-22kHz, A-weighted)
  • Signal-to-noise ratio: >137 dB, 20 Hz to 20 kHz, A-weighted
  • Output noise: Volume at 0 dB; 27 Ω input termination; 20 Hz to 20 kHz, unweighted
  • Balanced output: <2.0 μVRMS
  • Single-ended output: <1.5 μVRMS

Pricing (P1.5 or L1.5 each):

• UK: £34,200
• US: $39,500
• EU: €41,500

For more information visit the CH Precision web site.

• P1.5
• L1.5

Related posts:

• CH Precision Launches 10 Series DAC – The C10