Pearl Phantom Powered Electrets
Here is an interesting range of Electret capacitor microphones from the Japanese company, Pearl. They have chosen to make this range of electret mics phantom powered, which is unusual but not unique. Phantom powering means balanced connections to the mic, feeding the powering current to the mic electronics (the capsule is of course permanently charged and does not need external polarizing) along both signal wires in parallel, using the screen as return. The powering voltage needs to be between 12 and 48 volts DC.
True, capacitor mics are nowadays phantom powered with similar voltages, however, DC to DC conversion at the mic is usually employed to keep the working conditions identical from the range of powering voltages allowed. The Pearl mics do not have this compensation, so for maximum SPL use, the full 48V is desirable.
The basic reason for the adoption of phantom powering is to make the range fully acceptable in studios on standard phantom powered mic lines. Avoiding batteries in mics is a good thing — they always fail at the most vital moment!
Three Pearl mics were submitted for survey all with XLR connectors. Two phantom powering boxes were included together with Pearl leads, mic clips and a suspension spider.
This has the classic 'studio' upright look and is the flagship of the Pearl fleet. The published curves show a respectable wide, flat response and a good front to back cardioid characteristic, which however, narrows a little at high frequencies and has reduced front to back discrimination at high frequencies.
There is a low frequency cut switch inside the main body together with an 8dB attenuator switch. This operation is performed at the capsule itself by connecting a capacitor in parallel.
The electronics consist of an IC followed by NPN and PNP transistors to provide the symmetrical balanced output. There is no transformer employed. The electronics headroom is determined by the phantom power voltage employed.
This model is the only one in the survey which can be internally powered by a PP3 battery. It is connected via a diode, so it can be be left in situ whilst higher voltage phantom powering is used. One little aspect became evident as one played around with the mic — the body 'rings' if it is hit, less so when the battery is in place! Probably of little consequence in use, but deserving a little attention I feel.
The CR57 is supplied with a stand clip into which the mic is fixed by a large threaded ring. The mic clip, like those supplied with other mics mate with three different stand threads. The description sheet supplied has a curious error concerning the phantom powering, implying erroneously that pin 2 has the +ve voltage and pin 3 has the -ve voltage! In fact it is pin 1 which has the -ve (and described so) with pins 2 and three both +ve. The other mics descriptive sheets also have the same error but it is correctly stated in the battery power unit sheet.
This is a stock mic with similar characteristics to the CR57. However, there is no alternative built in battery facility. There is an externally mounted 8dB attenuator switch with similar electronics to the other mics. Also, like the other mics, the source impedance is around 200R with a minimum intended input impedance requirement of 3k. This is the usual situation for 200R nominal mics.
This has a tapered body with ball mesh head and has characteristics suited to vocal use. Curiously the information sheets show identical cardioid curves to the CR25 model. It is obvious in use (see later) that it has different response characteristics — bass rolloff to compensate for the proximity effect and a HF 'presence' peak which assists vocal clarity in complex mixes.
Underneath the ball head there is the 8dB attenuator switch built into the other mics. Current consumption is around 3mA at 48V, as it is for the others.
This allows four mics to be powered and connected on to the balanced (or unbalanced) inputs on recorders, mixers or PA gear. XLR connectors by Neutrik are used. The box is powered by 12V DC and a separate mains unit is supplied which feeds the necessary 12V DC. The circuit of the unit is durably printed on the box top and shows the usual DC to DC convertor (oscillator, transformer, rectification, smoothing and regulation) providing 48V DC to the input sockets.
The phantom circuitry is the typical arrangement of parallel resistors for each mic line with capacitors blocking DC from the outputs. There is an on/off switch with LED indication.
This uses two PP3 batteries in series (18V) and powers two mics. A three position on/off switch flashes an LED as the mid position is passed to allow judgement of battery condition. XLR connectors are used and a solid construction is employed as with the PW48. The batteries firmly clip into the battery compartment lid — a nice touch.
This has a fairly rigid suspension system and therefore it will be the heavier mics which will have the greatest isolation. However, the Pearl mics surveyed do not seem to be particularly prone to stand-borne vibration pickup. (At least the CR25 is around average with the CR57 significantly below average.) Handling noise of the 'vocal' CR45 is also around par for the type. So the improvement with the SA1 is small and in the end it will depend on the particular stage situation encountered whether there is a need for the spider suspension. Four different adaptors are provided to allow the different diameter and tapered body mics to be accommodated.
It is not always possible to employ the mics in particular recording sessions for various reasons. The permutations of trying to recommend this or that mic for particular instruments are many and complex. Apart from the actual differences in sound produced in a given situation by a mic, due to its on axis and off axis responses, there is the nature of the monitoring system to consider together with my particular likes and dislikes compared to another users preferences. Publishing frequency curves would not provide any clearer an answer.
So its back to lining up a number of mics with the subject of the survey and hearing if there are any great variations or nasties. The CR57 just had to be compared to an AKG C414 and to relate to the other two an AKG D202 was set up.
The CR57 strikes one straight away as being particularly smooth and refined. Like the others in the range, it takes high levels at 48V powering and has the attenuator to assist at lower voltages. The cardioid characteristic is clean and uniform and it certainly produces a very natural type of sound. I think studio engineers should try one or two for various instrumental miking situations or 'natural' vocal miking (solo or chorus) otherwise they are missing a mic with a lot of appeal.
The CR45 is, in the writers opinion, most suitable as a vocal mic. The presence lift is considerable but there could be too much sibilant emphasis in some circumstances.
Interestingly, the CR25 has a similar overall sound quality to the CR57 but perhaps lacking the refinement of its higher cost brother. Again the cardioid pickup seemed uniform giving a respectable sound quality off-axis.
Further details can be obtained from Pearl Music Ltd., (Contact Details). Please mention E&MM when doing so.
Review by Mike Skeet