Audio-Technica 'Performance' Microphones
Audio-Technica's 'Performance Series' is a recent addition to their well known range of attractive, lower cost microphones. The PR80 and PR20 models selected for this review differ quite widely in quality of performance, although this is to some extent reflected in the difference in cost. Although primarily intended for PA use, the operation of these microphones under recording conditions is of some interest, for models such as these are undoubtedly pressed into service in many home recording set-ups, and even possibly some budget studios.
The PR80, priced at £73 inc VAT, is a moving-coil, cardioid model, with a tapered body that widens out a little more than usual at the head, to make a smooth transition into the slightly elongated ball-end, giving an elegant profile and a shape that is particularly comfortable to hold. The microphone body and the tough wire mesh head are finished in slightly differing shades of a matt metallic colour, with the rather functional appearance being relieved only by a black anodized ring, just below the head, which bears the model details in gold.
The output is balanced, low impedance (250 Ohms), via a three pin male XLR connector, correctly wired to give a positive voltage at Pin 2 for a positive air pressure on the diaphragm (ie. Pin 2 'hot', Pin 3 'cold', Pin 1 earth). The PR80 has a specified frequency range of 50Hz to 15kHz, with a response that is generally rising from around 1 kHz to reach a peak at 10kHz, before falling away very sharply to decline around the nominal 15kHz point.
The response below 500Hz is considerably modified by variations in working distance; very close-up use, such as is normally encountered with hand-held vocals, results in frequencies around the 100Hz region being boosted by more than 10dB. This sort of 'proximity effect' is an expected, and indeed normally desirable feature of a stage microphone's performance, for singers usually appreciate the depth and power that it can add to vocals. If the effect is excessive, or when a more natural sound is desired, the extra bass may be easily counteracted by employing a little bottom end roll-off, which also has the beneficial side-effect of forcing down the low frequency feedback threshold.
The feedback rejection of this model is generally good, indicating a well-controlled polar pattern, with no particularly damaging peaks in the off-axis response. In deliberate feedback provoking tests the initial onset of ringing was always at a high enough frequency for it to be corrected with EQ without excessively detracting from a vocal sound.
The built-in 'pop' filter seems to work efficiently enough in PA usage, but I found an additional foam 'blast' screen to be a necessary precaution for recording close-up vocals, as any susceptibility to popping is always more damaging under recording conditions.
Resistance to handling and impact noise is obviously an important feature of any microphone designed principally for stage use, and the Audio-Technica PR80 displays evidence of reasonably effective shock-mounting of the diaphragm assembly, however, handling noise is unfortunately given extra prominence by a rather high degree of upper frequency content.
An on-off switch is fitted to this model, located roughly half way down the body; although no locking mechanism is provided, the switch top is sufficiently recessed to make accidental operation unlikely.
The PR80 has a more than adequate sensitivity (0.14mV for 74dB SPL) for any close-miked vocal and instrumental applications, although this would be considered a little on the low side for general recording work.
Despite this being nominally a cardioid mic, the effective working area is actually rather narrower than this would normally suggest, but in practice this is not at all restrictive in any of the envisaged close-up applications, and doubtless also contributes something to the fine resistance to feedback that this model displays.
In use with a high quality, full range PA system, the PR80 is pleasingly bright and well articulated, with a little bass roll-off effectively tightening the slightly uncontrolled bottom end that becomes evident with some sound sources. However, the sound does possess a prominent colouration that gives a rather 'hard' quality to the midrange and results in a lack of the sense of 'openness' and transparency that some, admittedly rather more expensive, models can offer. Interestingly, testing this model with some more modest PA equipment tended to display this 'hard' midrange more as a useful 'cutting' quality, that was able to overcome an otherwise unexciting and restricted PA system response.
In recording usage, the PR80, in common with most stage vocal mics, sounds typically coloured with wide range sources, but performs well in a number of less demanding applications. Close-miked drums were adequate, if unspectacular, whilst amplifiers were generally handled very well, although I was aware of some tendency to emphasise the harsher element of the harmonically rich-sound produced by an overdriven guitar amp.
The response of the PR80 has obviously been specifically tailored to suit its use as a vocal mic, and it is no great surprise therefore, that it will record vocals to a reasonable standard, albeit with the uncontrollable imposition of a degree of 'character'. But, in view of the modest price, the limitations are by no means excessive, and the overall performance is certainly quite creditable.
The PR80 is supplied in a rigid, foam-lined protective carrying case, which incorporates a space for the furnished 5 metre XLR(F) to XLR(M) balanced microphone cable, and also the rather brittle plastic stand adaptor supplied.
Although the PR20 is a similarly styled moving-coil cardioid mic, it differs quite substantially from the PR80 in most aspects of its performance. Priced at £33 inc VAT, it is unashamedly a 'budget' microphone, and is clearly aimed at a different type of user, for it is a high impedance model, with a rather short, (4 metre), permanently fixed, unbalanced output cable.
The 10kOhm output impedance theoretically requires an impedance at the equipment input of something approaching 100kOhm, in order to avoid 'loading' effects, so unless an external matching transformer is used, the nominally low impedance microphone inputs found on most mixers will not be suitable. However, the 'compromise impedance' employed by 'Portastudio' and similar units, does not seem to cause any significant further degradation of the already limited performance which is good news.
The nominal frequency response is 80Hz to 11kHz, although at a working distance of just twelve inches the specified 80Hz is 10dB down, relative to 1kHz; indeed this model seems to depend on the bass boost provided by the proximity effect to achieve any sort of balance to the response. A substantial presence peak at around 3kHz combines with the severely restricted high frequency response to give the typically coloured and 'nasal' quality that generally characterises cheap dynamic mics.
However, when used with a small PA system, some surprisingly acceptable results were able to be achieved with speech and vocals, although with the unsophisticated EQ available, the early onset of 'ringing' proved to be the most restricting factor. The feedback problem seems to be attributable not only to frequency response variations, but also to deviations in the off-axis response that are perhaps to be expected of any 'budget' moving-coil model.
Under the most likely conditions of use, with a small PA system, the built-in blast filter performed adequately, and 'popping' was not a serious problem with close-up vocals, although handling noise was surprisingly high for a mic designed specifically for hand-held use, but once again, the problem is certainly given extra prominence by the large measure of upper frequency content.
Given suitable loading, the PR20 will produce more than sufficient output to ensure reasonably noise-free amplifier performance, especially as the mic really must be used close to the sound source in order to achieve anything approaching a balanced response.
This type of microphone cannot really be considered for serious music recording, and to be fair, I am sure its designers never intended it for that purpose. Any wide range source will inevitably show up the severe restriction at both ends of the frequency response, whilst the midrange aberrations impart considerable colouration. If sheer necessity compels its use, then close-miked toms or a fairly unimportant amplifier would probably be amongst the least damaging applications, but in any multi-mic set-up, the coloured off-axis response of the PR20, or any similar mic, will have a tendency to emphasise certain crosstalk frequencies, and some care must therefore be taken to ensure that the benefits of employing an extra mic are not outweighed by a deterioration in the overall sound quality due to increased sound spill!
The PR20 is equipped with a recessed on-off switch, the value of which is unfortunately limited by the excessive audibility of its operation. Also, unlike the more expensive model, no protective carrying case is supplied, but a stand adaptor is included, complete with alternative thread adaptor, and at this price, I would hardly complain.
Audio-Technica offer a considerable range of well conceived stage microphone designs, at very competitive prices, and the performance of the PR80 in particular upholds their reputation in this area. But, as the recording tests showed, microphone quality is perhaps the one area that should never be compromised by the restrictions of the available budget, and there is really no point at all in trying to 'make do' with cheap stage mics for the sake of an improvement in some other aspect of the recording gear, for if the sound is not right at the source, the end result must inevitably be disappointing, whatever the quality of the following equipment.
Whilst both of these models seem to perform very much as intended, neither was specifically designed for music recording, and although the PR80 is sometimes able to give a creditable performance, the PR20 can certainly not be recommended in this application.
PR80 £73; PR20 £33 inc VAT.
Details from John Hornby Skewes, (Contact Details).
Review by Dave Lockwood
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