Can you really use a £25 mic for serious recording?
The Superlux Sonata ECOH6A is a very low-cost capacitor microphone that the manufacturers suggest is suitable for both live and recording applications — and as it costs only £25 I had to test this claim!
A back-electret capsule around half an inch in diameter provides a fixed cardioid-pattern response, with a useful frequency range of 40Hz to 18kHz and a sensitivity of 22mV/Pa. Sound levels of up to 136dB can be accommodated and the transformerless output stage has a 200Ω impedance, which should match all standard mixers and mic preamps designed to work with low-impedance microphones. As this model is a back-electret design, it has inbuilt preamps, so phantom power is required, but otherwise it is quite conventional, with the usual balanced XLR output. You also get a zip-up nylon carrying bag and a rigid standmount. There's no hard case or shockmount, but at this price that is a perfectly understandable omission.
The microphone has the same slightly bulbous shape as some of its more costly Superlux stablemates, but there's no easy way to open it up to examine or compare the electronics. The capsule is protected by a dual-layer basket, and as the shape suggests this is a side-address microphone, with the 'live' side of the grille coloured silver and the rear black. There are no filter or pad switches, so you simply plug in, switch on the phantom power and go. (Of course, for vocal use you should be sure to add a step here: always use an external mesh pop-shield!)
For comparison purposes, I made some spoken-voice recordings with the Sonata alongside an Audio Technica AT2020, which I rate as one of the better low-cost back-electret mics currently available for studio use. The ECOH6A comes in at well under half the cost of the AT2020 and is a little less sensitive, but tonally it comes closer than it has any right to for the price.
The AT2020's sound seems a little better focused, and the ECOH6A can sound just a hint lispy on some voices, but I found that these differences were really quite subtle once the ECOH6A had been boosted in level by 3dB, to bring it closer to the AT2020's output. No noise figure is provided, but in normal close-miking applications I didn't notice any circuit noise intruding upon my recordings.
While I would never recommend skimping on microphones I'm conscious that some of us need to work on an exceptionally tight budget. You could certainly make good vocal recordings with this little mic, which combines a balanced sound with a useful degree of presence — and it also has enough sensitivity to work well with acoustic guitars and other instruments. So if you're in need of something that is both very affordable and capable of producing results that are at least in the same ball park as more costly studio mics, I don't think the Sonata ECOH6A will disappoint: it produces results that are far better than its price suggests.
For the money this is a very good little mic, and I'm not really able to recommend any sensible alternatives at the same price — though if you can afford something better, it may be worth it, as the microphone is one of the things that really define the quality of your recordings