COUNTERPOINT SA-5.1

Commentary

This tube type preamplifier was improved as a minor change model of SA-5.

The SA-5.1 uses 6DJ8, a vacuum tube for high-frequency amplification with extremely low internal resistance. It was designed with the aim of producing sound that takes full advantage of the excellent linearity of 6DJ8.
The equalizer stage consists of a CR type equalizer, designed to leave amplifier performance to the bare characteristics of 6DJ8 by focusing on non-NFB.

The power supply is designed separately.
The power supply unit contains a rectifier tube 6CA4.

There are 2 color variations of black and silver.

The wood case was sold separately as an option.

Model Rating

Type	Tube type control amplifier
Gain (1 kHz)	Low-gain RIAA input : 49 dB High-gain RIAA input : 65 dB
Frequency characteristic	5 Hz ~ 88 kHz (No Load) 5.5 Hz ~ 83 kHz (at 50k Ω load) 5.5 Hz ~ 50 kHz (50k Ω, 1000 pF Load)
Signal-to-noise ratio (100 mv, 1 khz Reference Input)	-86dB (400 Hz to 80 kHz, input short) -83dB (20 Hz to 80 kHz, input short)
Total harmonic distortion factor	0.18% (1 kHz at 1 Vrms output)
RIAA deviation	± 0.05 dB (40 Hz to 22 kHz)
Rise time	4 μ sec (No Load) 7 μ sec (at 1000 pf Load)
Maximum power output	30 v (peak)
External dimensions	Body : Width 483x Height 64x Depth 297 mm Power Supply : 105 mm W x 110 mm H x 293 mm D
Weight	Body : 4.7 kg Power supply : 3.4 kg
Sold Separately	Wooden case (¥ 38,000)