The CAYIN Soul 170I tube integrated amp has such a distinctive dual personality that it is like buying two amps for the price of one.
At RM26,000, the CAYIN Soul 170I is quite affordable and you are effectively paying RM13,000 per sonic signature.
This dual personality is due to the design of the amp — it has a Triode Mode and an Ultralinear Mode which can be changed on the fly just by pressing a button.
On Triode Mode, the amp is a 75-watter per channel; on Ultralinear Mode, the power goes up to 130 watts.
Not only does the power change, but the sound signatures too. This where it gets interesting
On Triode Mode, the sound is smooth, warmish, organic, dense and a bit lush. Images are amorphous with ‘hazy’ edges while the depth of the soundstage goes quite deep. The bass, however, becomes more ‘tubey’ as in a bit loose and light.
On Ultralinear Mode, the sound quality suddenly changes to be more dynamic and more forward. The singer, especially, is thrust forward from the mix. Images are leaner, but much better defined. Transparency improves and there are lots of micro details. The bass becomes tighter though not as deep and tight as the best solid-state amps like the Boulder. It is a totally different kind of sound which is closer to solid state. But it still retains some tube flavour.
So which sound would you prefer? Some audiophiles say the Triode Mode is for listening to jazz or rock ballads while the Ultralinear Mode is for faster-paced music like rock. True enough, Lou Reed sounded much better on Ultralinear Mode while Diana Krall sounded lush and smooth on Triode Mode.
In my case, I spent some time listening to ballads on both Triode and Ultralinear Modes and after a long while I decided that I preferred the extra dynamics, clarity, tighter bass and better imaging of Ultralinear Mode.
The CAYIN Soul 170I is not only named after the big KT170 power tube but is designed for it. Once New Sensor Corporation and Tungsol announced its all-new KT70 flagship tube, CAYIN decided to build a Class AB Push-Pull amp to fully utilise the characteristics of the tube.
The Soul K170I also uses a special 22DE4 tube rectifier for the power supply while hand selected ECC83S are used for the voltage amplification stage, and special 6SN7s for the driver stage.
The integrated amp features three pairs of line inputs, one pair of balanced inputs and one pair of ‘Pre-In’. It also has one pair of dedicated subwoofer outputs. Speaker terminals are offered for 4 and 8 Ohm speakers.
There is a meter on the top plate for easy adjustment of biasing.
When I started listening to the CAYIN Soul 170I integrated tube amp, I used a pair of Duelund interconnects with Duelund Paper RCA plugs from the DAC to the amp. But the soundstage became rather narrow and the sound was congested. Replacing with a pair of WyWire Platinum interconnects opened up the sound quite a bit. So you may need to experiment with interconnects to get the best performance from the CAYIN Soul 170I.
As for build quality, I must say it is very impressive. It looks and feels solidly made, and weighs quite a bit. But I have to say that the amp generates quite a lot of heat.
The CAYIN Soul 170I is available at Stars Picker. It retails at RM26,000.