Unitra WSH-605 Integrated Amplifier

Introduction

Unitra is a new brand to the UK Hi-Fi market, but it has a long history in its home country of Poland, with over 30 years of experience. There, it is one of the most well-known brands for home entertainment. For example, a Polish friend of mine said that in the 1990s, his family and everyone he knew owned a Unitra radio and often a TV as well.

The primary focus of this review is the Unitra WSH-605 Integrated Stereo Amplifier. I will also be mentioning the CSH-801 CD player, which was provided for this audition. The company also manufactures and sells a range of other products, including turntables, loudspeakers, and accessories.

Design

The 70-watt-rated Unitra WSH-605 is the smaller and less expensive amplifier that Unitra offers, yet the larger, dual-mono-designed WSH-805 lacks the onboard DAC featured here. While the larger model is unashamedly retro-looking, complete with huge back-lit VU meters, the slimmer profile of the WSH-605 offers a more timeless yet classically styled look in either silver or black finish. Built onto an all-metal chassis, my silver review sample looks stylish with its brushed aluminium front panel, home to four rotary controls, two chunky toggle switches and a 6.3mm headphone socket.

On the rear panel, there are four line-level inputs as well as a phono input and ground terminal for moving magnet (MM) cartridges. Two digital inputs are provided, each supporting either coaxial or optical connection, feeding the highly regarded ESS SABRE DAC. The PCM digital audio is supported up to 192kHz, 24-bit, so all hi-res streaming options are catered for. Also on the rear panel is a single set of high-quality speaker terminals, capable of accepting banana plugs, spade connectors, or bare wires. Should you wish to use a subwoofer (or a different power amplifier), Pre-Out jacks are included, with all preamp functions—volume, tone, and balance active.

A remote control is included to adjust the volume, mute the output, select sources, and put the unit into standby. Additionally, the linear key enables tone adjustments to be auditioned from the listening position; a nice touch.

The WSH-605 incorporates Unitra’s gain error correction technology within the power stage, rather than using conventional feedback circuits usually employed in this type of amplifier (effectively, the error correction compares the signal after the output stage with that at its input and adds the difference back to the input). This is said to minimise harmonic and intermodulation distortion and is likely a significant contributing factor to the amp’s clean nature.

CSH-801 CD player

This is a brief overview of the CSH-801 CD player, which was sent along with the amplifier. First of all, let me tell you that it sounds superb. In the golden age of CD, 25-plus years ago, this quality of reproduction would have cost several times the asking price of Unitra’s unit. Its DAC is 32-bit with a sample rate of 384 kHz (PCM). You can also use the digital outputs to feed an external DAC if you wish; however, the onboard DAC is hard to beat.

The e-ink display shows track information and suits the 1970s look of the unit, which itself matches perfectly with the WSH-605 amp. The display is backlit with a warm glow, offering five levels of brightness, or it can be switched off completely. The CD view port is similarly backlit; however, this can’t be adjusted or switched off.

The rotary control on the facia allows you to skip tracks or scan through audio at rates of 5-, 10- or 15-times normal speed.

Specification and Price

Performance

Review Equipment

Leema Stream IV streamer/CD player

Garrard 401 turntable – SME 3009 – Hana ML

Icon Audio PS1 phono stage

Tannoy Berkeley loudspeakers

Chord Shawline interconnects and speaker cables

Impressions

First impressions of the Unitra WSH-605 integrated are of an extremely clean and sprightly sounding amplifier. There is a purity to its character that blesses the amp with a crystalline quality. It’s likely that Unitra’s unconventional gain error technology is mainly responsible for the amp’s pristine sound. This sense of vanishingly low harmonic distortion ensures an unadulterated account of music, presenting well-recorded tracks with accuracy and precision. Those who like their music replayed with added warmth and harmonic ‘enhancement’ of the thermionic kind might consider the WSH-605 a little clinical in nature. However, in truth, it’s the absence of spurious euphony they’ll be missing. If you do feel the need to deviate from the amplifier’s natural sound, the Bass and Treble controls offer usable broad equalisation curves at either end of the frequency spectrum. A slight bass boost fleshed out the sound of some old mono 45s from the 1960s to significant effect.

During my time with the Unitra amp the much anticipated (by me at least) Nick Drake box set ‘Making of Five Leaves Left’ (Qobuz 16-bit, 44.1 kHz) landed. While some of the home demos are a low-fi listen not worthy of HiFi assessment, the early studio out-takes of solo guitar and voice performances, without the overdubbed strings of the familiar versions, sound achingly beautiful.

The transparent and faithful nature of the WSH-605 brings out the pensive emotion of the material without coming across as syrupy, as I sometimes find with the old valve amps I use.

Playing more full-range and busier rock material highlights the amplifier’s midrange detail prowess, helping to keep voices and instruments distinct. Black Sabbath’s ‘Paranoid’ (2012 Remaster, Qobuz 16-bit, 44.1 kHz) isn’t the most HiFi friendly recording by a long shot, however the Unitra’s slightly mid-forward character prevents it from becoming the dull and bloated fuzz-fest that more lethargic amps often do.

Rhythmically, the WSH-605 is spot-on, capable of an excellent turn of speed. More modern recordings, such as Michael Kiwanuka’s ‘Rolling’ (Qobuz 24-bit, 48 kHz), really show-off the amp’s ability to groove. And that track’s retro/modern vibe fits nicely with the aesthetics of the Unitra equipment. Fans of up-tempo, dance music will love the rhythmic agility of this amp.

Headphone Output

Listening on headphones through the onboard headphone amp is a joy. The amp has enough juice to drive my insensitive HEDDphone Two reference cans, sounding equally as good as my Naim NAIT’s Class A stage. Plugging in the ‘phones mutes the output to loudspeakers, however if you’re dialling up the wick to achieve reasonably loud levels through power-hungry ‘phones like mine, remember to reduce the volume before unplugging and reactivating your loudspeakers.

Moving Magnet (MM) Phono Stage

For vinyl lovers, the Unitra’s moving magnet phono stage is perfectly fine for the sort of sub-£200 cartridges many people use; however, using a step-up transformer with my Hana ML moving coil that retails for just north of £1,000 reveals its limitations; the onboard phono stage doesn’t quite achieve the superb fidelity of the line-level channels. For most of my LP listening, I plugged my Icon Audio valve stage into the Unitra’s Aux input for a wonderful all-analogue experience.

Overall

Unitra’s WSH-605 is a fine amplifier for the money, providing excellent analogue and digital connectivity. It has a fast, detailed sound not dissimilar to my Naim NAIT XS3, offering superb resolution and pace.

If streaming and CDs are your preferred choice of music consumption, the WSH-605 could very well meet all your ongoing amplification needs.