SPL Phonos MM/MC phono stage
German company SPL is one of a small coterie of brands that produce components for both audio enthusiasts and professional studios. There aren’t many other electronics companies whose products are used extensively in both worlds, this is more common with loudspeakers where the demands are not so different but if you can think of more than a few hi-fi brands that make compressors, equalizers and mixers then you have a better memory than me.
Working in both worlds is no guarantee of quality of course, but the pro world does make greater demands on reliability and consistency than the domestic one, and it’s less concerned about appearance, which is a major factor in the cost of high end audio. SPL (Sound Performance Lab) makes a lot more pro than domestic gear and the Phonos is the only phono stage in the list. It sits alongside a DAC, preamps, power amps and headphone amps as well as a preamplifier with built in crossover for serious active action.
The Phonos is unusual in that its various settings are easily accessed on the front panel. With four capacitance settings for moving magnet cartridge and six impedance settings for moving coil it has a good range for both and this placement makes it easy to compare the effect of each. All too often phono stages that have this facility hide it on the back of the box and offer fiddly dip switches that make it much harder to contrast. The Phonos also offers three levels of gain and a subsonic filter, the latter cuts out frequencies below audibility (under 20Hz) in order to make the amplifier and loudspeaker’s life easier and is generally a good idea. The only switch that I would like to have seen is a mono one for single channel recordings, but that is a niche pursuit even for a phono stage at this price.
Things are equally if not more interesting inside the Phonos where SPL employ tech called Voltair, this is a power supply that runs on 120V DC rails, which is four times the 30V found in the majority of audio electronics. To achieve this SPL built their own high voltage op-amps which run at +/- 60V and this is claimed to offer greater dynamic range, more headroom and lower distortion and noise. The figures that SPL gives suggest that this is by a significant margin.
Another interesting element of the design is RIAA equalisation based on the recommendations of Douglas Self, a British electronics engineer and the author of six books on audio electronics including Electronics for Vinyl. This has resulted in the use of multiple small capacitors doing the job that is usually given to a few larger ones, the idea being that smaller devices charge and discharge faster.
Sound quality
On the connection front the SPL Phonos is equipped with high quality RCA sockets for in- and output as well as a ground terminal that accepts spade, bare wire or 4mm plug connections. I hooked up a Rega Naia turntable with the Rega Aphelion 2 moving coil cartridge to the SPL and set the impedance to 100 Ohms, the subsonic filter to on and the gain to max and dropped the needle in the groove. The resulting sound was dynamic and vivid, with an even handed neutrality that is typical of electronics from a pro brand. Where regular audio engineers frequently voice or tune components to have a particular sound, their studio oriented counterparts go for a relatively flat response that doesn’t accentuate any particular part of the spectrum.
This approach means you get more breadth of variety in recordings, which proved to be the case here with a couple of recent albums delivery everything from mellow sweetness to drive and grunt depending on the recording. Both are great recordings, Julian Lage’s Speak to Me and Liv Andrea Hauge Trio’s Ville Blomster, the former a jazz guitar album with accompaniment and the latter a piano trio. Both offered up nuance and power when required via the Phonos, the preamplifier extracting strong levels of detail and very low noise.
In some respects the neutrality of the Phonos does not suit the Naia as well as it would more conventional turntables. This Rega is devoid of the thick, warm sound found with the majority of turntables, it’s an extremely even handed turntable that makes everything I have compared with it sound fat and blurred. So the Naia/Phonos combination does not have the bloom you get with many turntables, but that does nothing to stop the pairing delivering an awful lot of what’s great about vinyl.
If you read my review of the Oephi Immanence 2.5 loudspeakers you will see a lot of lyrical waxing about the sound of vinyl, much of which was produced by the Naia and Phonos pairing which delivered a distinctly more thrilling and engaging sound than the digital alternatives I had to hand. The combination extracted huge amounts of refined energy from each record and presented it in a wholly coherent and engaging fashion, the lack of bloom means that images can be smaller than with other phono stages which sound a little richer by comparison, but this comes back to the absence of colouration in both turntable and phono stage. The Phonos is all about resolving the information that the connected cartridge produces, it doesn’t seek to sweeten or enliven it and this means you hear a sound that is closer to the truth than usual, one that gives the highs and lows of emotional communication that the music was created for.
It was interesting to contrast Laura Marling’s Soothing (Semper Femina) on vinyl with a streamed version of the same track, the tonal balance was almost identical which is rarely the case, yet the Naia/Phonos rendition was more open and the voice more beautiful and beguiling thanks to the more natural sound of the format. Donny Hathaway’s Everything is Everything (1970, Speakers Corner) sounded a bit brash and hard edged by comparison but the brilliance of his voice and tunes like The Ghetto are so engaging that you forget about the sound and become immersed in the music.
The SPL Phonos also encourages higher playback levels by virtue of its low noise and wide dynamic range, tracks with serious bass on are particularly enthralling when played at volume. One such is 12 Tribes of Israel by Linval Thompson (Select Cuts From Blood & Fire, Chapter Two), this dub track has plenty of fat bottom end on it and this can often get overblown, but the SPL delivered it in tight, controlled yet powerful fashion that had the block rocking. It’s a lot of fun with a degree of precision not normally encountered in a phono stage. This works equally well with the timbres of a string octet and the interplay of a piano trio, it’s neutrality ensures that it will work well with pretty well any decent recording. The less well executed or more compressed ones will sound the way that they are, when you open the window more of whatever is in the recording comes through.
Conclusion
The SPL Phonos is one of the only phono stages you can buy that is made by a company with a strong presence in the pro audio world, as a result it has an even handed neutrality and does not attempt to polish or exaggerate for effect. It will allow the character of any cartridge and turntable to shine through. Whether anyone spending this sort of money uses an moving magnet is a moot point but I did spend a very enjoyable afternoon with a very good step up transformer between turntable and MM input and can report that it worked a treat. The Phonos has intrigued me about SPL, they clearly know their sonic onions and I will be investigating other products in the line as soon as the opportunity arises.