What is... a sound card?
Autistic loudspeakers and company
lately it has become fashionable to limit costs to the minimum, as with the Winmódems, which were using the potency of our processor to fulfill several components that simply they do not have. In case of the loudspeakers, one speaks with a lot of potency facility of "60W, 120W, 200W..." musicals or PMPO, which in fact are 5 to 20W real; and of course, a few good loudspeakers it is IMPOSSIBLE that they cost 3.000 ptas, as any fan of the sound knows.
The last bet in the saving there are the loudspeakers USB. Theoretically it looks like a good idea, we send the digital information for the port USB and the loudspeakers are in charge of reproducing the sound. There are no complications and the reproduction quality is quite high. Also all these solutions (like that of Philips or Microsoft) also come with a Subwoofer, for what his reproduction quality is quite high. Also, we have saved ourselves the money that costs a sound card.
As major compensation, his best advantage: on not having included nor to need sound card: does anybody know how to record it? We will not be able to connect a microphone and enjoy the entertaining Karaoke programs. Although if his is not to sing "I Have a yellow tractor" he can live without this option. Also it is necessary to say that the price is not one of his biggest strong ones, compared with conventional loudspeakers of good quality, with solutions of 2, 3 (2 + Subwoofer), 5 (4 + Subwoofer) or 6 (Dolby Digital) loudspeakers.
Also like conventional loudspeakers (because we have to connect them to a sound card) we can include to the monitors with built-in loudspeakers, with very much style and a quality of acceptable sound (if one is not a purist, skylight). A big election for "offices with style".
Connecting our card with the exterior (and the other way round)
We all have the rear part of our computer replete with a jumble of cables. Part of the fault has the sound card.
Traditionally connectors mini - jack have been used, like those that we use in our portable radiocasete. These keep on being the most common in the solutions of low and average level. It is a question of analog communications of half a quality, which is not sufficient in many cases.
The explanation is simple; if, on having recorded the sound, it gets lost a little of quality, when we treat it a bit more and on having recorded to support (on the outside) small other, in whole we have lost 2 few ones and a bit, while with other solutions we will lose only a bit.
Traditional connectors in the chains or domestic sound mini stereo systems are the RCA. Normally every RCA is an independent channel (while in Jack 2 together channels go). For it they always go of two in two (clásicamente the red one is the right channel and the target the lefthander). They offer major quality that the connectors Jack traditional but they are more expensive and less compact.
If we look for professional quality, we will have to praise ourselves for a card with earnings and exits S/PDIF or digital optical exits. This one has been developed by Sony and Philips to design an interface of digital connection of high services. On having treated to the sound digitalmente, quality losses do not take place never on having gone on from digital support to the computer or vice versa.
Finally, the earnings and exits MIDI. They will be necessary in case we are going to work with devices MIDI as it could be a keyboard. With the entry MIDI, our compositions will be much simpler, since we will have only to connect our keyboard, and the score of the piece that we touch will appear on the screen of our computer (if we are provided with the suitable software).
If in addition to entry, we have an exit MIDI, any score in this format will be able to be reproduced by a connected instrument, from a keyboard to a rhythms box passing for a guitar or a drummer (whenever it is MIDI, of course).
In addition to these external connectors, there are also interns, being more important that it goes to the CD - ROM, to be able to listen to the music CDs. It can be a digitalis (only in the most modern) or the typical analogical one, of which some time ago there were several now already unified formats (for CD-ROMs Sony, Mitsumi, IDE...). And in some ancient cards there was included a connector IDE of 40 pines for the CD - ROM (when the CDs-ROMs were slightly "extra" and the EIDE did not exist with his 2 channels).
Formats or the fever of the MP3
The last point that we are going to treat is that of the audio formats. Perhaps this leaves a little of the context hardware, but it is interesting to know them to know our needs and therefore to find the card that better adapts itself to our possibilities.
Digital audio in format of wave or audio CD or.wav or.au (the wav of the UNIX). It was the excellent format to store the digital sound. His principal advantage, his quality, his principal disadvantage, the space that it occupies. To do an idea to you, in a CD they fit "only" 74 audio minutes to the maximum quality: 44,1KHz, 16 bits and stereo (2 channels).
Normally, when we record sound in the computer we will do it by means of this format, the wave format. With him, the positions of the sound are stored without any compression in every moment. Simple and effective, but with the problem of the space.
With the format MIDI the problem of the space is solved. It is completely different from the wave format, with him, we will only store the notes that will have to be touched in every moment. Therefore it allows big flexibility and it is ideal for composers. Nevertheless, to obtain an acceptable quality, it will be necessary that our card has wave table or, in his defect, a virtual synthesizer as the Yamaha seen previously. Another important lack is that we will not be able to add human voices, they cannot be synthesized as easily as the sound of an instrument.
The format MIDI is not already used as earlier to give music to games and multimedia productions, since the capacity of the CDs does that it is possible to include the melodies in wave format, with the advantage of being able to include songs with voices (of persons).
On horseback between both are the modules. The modules come from the world Friend, and have very interesting characteristics. On the one hand the notes are stored, as in the MIDI, and for other, the instruments, as if of a wave table it was talking each other. Therefore, we can record voices as one more instrument and use them in our compositions. With the modules high quality productions can be obtained and of the most diverse styles, as for example this one.
Finally, the megafamous person and siemprepolémico.mp3. Mp3 is only a specification for the compression of wave files (the.wav). With him it becomes possible to reduce the original size of the files in approximately 10 times, although we can to change how many compression we wish. The compression normally is with loss, losing part of the sound, good for being redundant information or for be cutting of areas where scarcely the human ear comes. In practice, few persons can distinguish between an original song and one in format mp3 (personally only I have been capable of doing with a song with a compression ratio from 15 to 1 from 15 to 1 and paying attention during several reproductions, never to the first one). Hence, of Internet and of excellent breeding animals like the Winamp, big part of his success.