Cayin RU7 DAC review – Fantastic Portable Sound

Cayin RU7 is the brand’s latest portable DAC, and it wants to improve on a very popular RU6. To achieve that, Cayin decided to change some things so let’s dig in.

Build and Features

RU7 comes in the same form factor as its older cousin. A mix of scratch-resistant glass and aluminium is used, and the device appears well-built. Digital input is done via USB-C connector, while two analog outputs let you choose between single-ended 3.5mm and balanced 4.4mm. A small OLED display will help you navigate the volume and settings.

Inside the unit, D/A conversion is done by a miniaturized 1-bit DAC circuit, made with discrete components – a resistor network composed of 128 pcs (4 x32) high-precision thin film resistors. We’re talking about a fully differentiated 4-channel DAC architecture. Amplification is done with dual amplifiers in parallel, providing output power of 160mW @32Ω for single-ended output, and 400mW @32Ω for balanced one. Voltage is also different with 1.2V for single-ended, and 2.4V for balanced out. This means that you should utilize a balanced connection if possible because it will provide higher voltage, and more power, resulting in better sound quality.

Sound

Sound over single-ended out is very competent. There’s nothing to complain about really. Tonality is well-balanced, tones appear clean and well-separated, and power is sufficient for most IEM models. But the real fun starts once you use the balanced connection. Soundstage size immediately increases, there’s more empty space around and between instruments, more air, better layering, and more precise pinpointing of instruments. The difference is not small at all. As previously mentioned, voltage and power also get a solid boost so driving bigger headphones becomes easier this way.

One thing to note here is that RU7 takes a bit of a tonal shift compared to the older Cayin RU6. That one was done with R2R technology and boasted a thicker and warmer sound signature. RU6 had a noticeably higher noise floor and it was never able to create a fully dark background – something that RU7 does with ease. RU7 also layers better, separates tones better, and simply sounds cleaner and more resolving. But if you hoped for that warm and thick sound, you won’t find it here. Subjective preferences are not something worth arguing about, but RU7 is objectively a more transparent, more resolving, more spacious-sounding DAC.

Another Comparison

Hiby FC6 is a small R2R DAC of a similar price. This one however offers only single-ended output but was nonetheless one of my favorite DAC dongles at this price, thanks to its full and natural sound. If you’re for some reason able to use only single-ended output, FC6 holds a slight advantage in the overall sound quality. Both DACs offer similar detail retrieval but FC6 manages to sound slightly fuller and more palpable. However, move to RU7’s balanced out and it will quickly take a lead with more spacious and airier sound, better layering, and better precision. The difference is not big by any means and both of these belong to the same performance tier. But given the price is the same if you can use balanced output, RU7 is a better choice.

Conclusion

Cayin dared to experiment and make a new model using different D/A conversion technology. The sound signature is different now but RU7 is to my ears a clear improvement over RU6. The price didn’t go up much either, making RU7 go head-to-head with my previous favorite DAC dongle around this price point – and winning. To put it simply – great device.