Viewing a single comment thread. View all comments

Leading_Study_876 t1_j300rzz wrote

Reply to comment by [deleted] in How is stereo information encoded into a vinyl record? by caedin8

No, just left and right. Believe me, I just retired from working 35 years in the HiFi (turntable manufacturing) business. But - in most music recorded by microphone, bass is pretty much mono. The wavelength is so long that the signal picked up by the left and right microphones will be almost identical. That’s why you can put a subwoofer almost anywhere in a room and it won’t make much difference.

If the left and right channels were cut IN PHASE then this common movement would translate to a pure vertical movement of the stylus. This is bad news, as it can make the stylus lose contact with the record surface. So one channel is phase reversed (180 degrees) so that the common signal then translates to HORIZONTAL movement. Only the difference between L & R makes the stylus move up and down.

Note: I had previously forgotten this phase reversal detail, but it came back to me, and so I have now edited this post to correct the above paragraph. This other Reddit post on the subject is very informative!

It is of course possible for an engineer to put a full bass track on one channel, but there’s no real sense in doing that. If they want to make it seem like the bass player is standing on one side, they only need to put the mid and high frequency harmonics over there but the low frequency stuff should be mono, so you don’t overload the bass drivers or amps on one channel, and run the risk of hitting the end stops on bass drivers at high volume, which sounds bad and can damage the speakers.

5

fer_sure t1_j30f8lo wrote

> the low frequency stuff should be mono, so you don’t overload the bass drivers or amps on one channel, and run the risk of hitting the end stops on bass drivers at high volume, which sounds bad and can damage the speakers.

So, has anybody ever done that deliberately? Like encoding a signal that can destroy a record player or speakers? Is there a record of doom out there?!

0

roesingape t1_j30w4gb wrote

There's many. I was in the east coast noise scene in the aughts. Many artists recorded many things that either sounded exactly like destroyed speakers or destroyed speakers if turned up too loud or they'd record destroying speakers and destroy speakers playing that through speakers. Or sometimes just use already destroyed speakers to begin with just to get that sound.

Like all true art music, it was more fun to do than to hear.

EDIT: Spleling

2

NL_MGX t1_j30o17b wrote

I recall having a record where the bass is so heavy you can see the groove wiggling and you need to be careful not to spin the record too fast or the needle would jump out...

1