Setting Old Stereos To R.I.A.A Standards.

Okay first what is high fidelity ?  In short high fidelity are the frequencies that can be heard by a healthy human ear (20 to 20,000 cps,{cycles per second}) .If you ever listened to an old 78 R.P.M the sound range was very limited.

  Stereo of course is separation  the very first ones only let you hear the bass from one speaker and treble from the other but the records still only played one groove at a time. 

  Then stereo records came out which had an inner groove (left channel ) and outer groove (right channel) in other words stereo records play two grooves at the same time one for each channel, not only that but any sound reguardless  of being bass, treble, midrange can be recorded in either groove.

  In the late 1960's a test record came out and it help people to set their stereos to the R.I.A.A standards, instead of just hearing separation from two different places you now can hear the sound in a 180 degree arc (1/2 of a circle) if one was just sitting between the two speakers.

 In other words it created "ghost" channels that "seem" to appear outside the speakers, for example girls singers in one channel, boy singers in the other channel and the main singer in both channels.

You still can hear the two channel separation ,but you can also hear

the main singer that seems to be in the middle of the speakers.

Of course we have something like 7.1 stereo now, meaning 7 speakers, each one with its own sound ,and  the .1 means one            woofer or bass speaker.                                                                                                

click here for example of 2 channel stereo 

Note:  It will sound better on desktop computer speakers.

click here for an example of 180 degree music 

That is if your stereo is setup to R.I.A.A standards violins will seem to be in the left middle for example.