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To select a dictaphone, you should at first choose its type. There are microcassette and digital.
Microcassette dictaphones are easy. The quality of record depends on the device and on the cassette quality. Their advantage is low cassette price. You can buy a lot of cassettes and you won’t have to worry about record time. Additional functions – autoreverse, autostop, voice activation, tape counter, record indication. But such dictaphones are already in the past, so lets look at the digital ones.
Digital dictaphones record information to inner or changeable flash-memory. It is quite expensive, so you’ll have either to buy a larger memory, delete unnecessary files or transfer records to the PC. I wouldn’t recommend you to buy dictaphones without changeable memory, because you will always be restricted to the inner memory sizes and you won’t be able to extend it.
Digital dictaphones can have a lot of additional functions. Besides those in microcassette ones, there can be an alarm clock, facilities for record processing, diary and others.
Digital dictaphones can (and must) be connected to PC. The process of record transferring by means of audio card, connected to the earphones output, isn’t normal. The record quality is lost. The optimal is connection through USB. When you buy a dictaphone, take a look at the kind of USB it has. First, it is better if it has USB 2.0, the transfer speed is higher. Second, there can be usual USB or mini USB. The last one can be connected to PC input only through adapter. If you already have video camera or digital camera with mini USB, then you can buy it, this adapter will be used for few devices. If no, then one precious input in your PC will be always occupied by dictaphone.
The record quality of digital dictaphone depends on the device, its microphone, intake duct, signal sampling rate and the method of its coding. Human ear can perceive frequencies from 20Hz to 20KHz. Normal speech is between 0.3-3.4 KHz, i.e. to understand, what the person says, the tape of 0.3-3.4 KHz will be enough. The rest is just additional noise. So if you want to tape only voice, buy the dictaphone under 4kHz (according to Nikewist theorem, the sampling rate should be 8 kHz ). If you want to record other sounds (music, the falling of objects), then you should buy 20kHz dictaphone (40kHz sampling rate). But remember that the wider is the strip, the bigger is the memory expenditure.
The construction can have various forms. Along with classical ones, they can be also in the form of usual objects, for example, pen, if you have to make a secret record. They can have an EPU to work from power circuit, a module for connection to your phone, to record your telephone conversations. As for its design, it’s up to you to choose a proper one. |