Auto BPM Readout

Oh wait, way back in post #2 you said this doesn't have a BPM display. So, your unit doesn't show the tempo. It really seems like you're just over thinking this. Put a CD in and play around with the pitch knob. It should become quite obvious to you in a few moments.

If you still want to mentally analyze this, consider this; if you had a turntable with a 33.3 RPM record on it with just a kick drum making a 120BPM track, you'd have a drum sound every half second. If you sped your table up to 66.6RPM, there'd be a beat every 250ms (240BPM). Likewise, if you had a record on it that had a steady 1kHz tone at 33.3RPM, it would become a 2kHz tone at 66.6RPM. Can you see how pitch and tempo are inexplicably intertwined with a mechanical device? That's what the pitch knob on your player emulates. Although, it doesn't have such a wide range of effect. I believe your player is limited to +/-24% at most.

 

Everything you said makes sense, and that my unit changes the pitch according to the beats per minute at the same time, it has no auto bpm readout so it must be done by ear.
If a unit was used that had separate tempo and pitch knobs, and tempo was set to the bpm, then separately how do you know how to set the pitch to match the tempo?

 

Of the units I've seen, there's only one knob with switches to determine what that knob does. Like tempo, or pitch, or both. But conceptually, let's try to answer your question, "how do you know how to set the pitch to match the tempo?" There is no matching of tempo/pitch. You would adjust either/both to match whatever you feel is desirable. If you desire to keep the original tempo, but match the tuning of your instrument you're trying to play along with the CD, then you could do that. Or, if you like the key the music is being played in, but you want it to play at a different tempo, you could do that. So you see, this is not about fixing defects to make something correct or right, but rather adjusting some parameters to match how you desire it to be instead.

 

So, if I place a CD in a CD player unit that has pitch/tempo (bpm) control and set it to 0.0, is it playing at the correct bpm? Is it only if a unit or program like Virtual DJ knows what the bpm is (by a bpm readout feature) and doesn't need change because it already knows it (adjusted accordingly) to the correct Pitch/tempo (bpm), and doesn't need to be set manually? Is there no need for adjusting of tempo/pitch period, for any standard music recording on a CD?

 

Depends on your definition of 'correct.' If correct means to listen to it how it was recorded, then yes. If correct means what it takes to make a smooth transition to another song of a different tempo, then no. If correct means you want to the recorded music to play in the same key as your instrument you're playing along with it, then probably no.

No idea what this question is asking.

Depends on what your needs are. See the first answer in this post.

 

All I was asking was if the pitch/tempo is off, does a unit without a auto bpm readout know the bpm exactly, and that is where it sets it.
How does it know where to set it, if it doesn't have the bpm readout?

When you say transition to another song, is this in example of 150 bpm to 120 bpm meaning making a change of pitch/tempo of the difference or only if I want the next track to match the previous one?

 

Alas, I still think you aren't grasping the function of the display. It merely displays what the measured BPM is. The player does not use this information to adjust or change anything. That is something left up to the human in charge. As such, the display is a convenience feature. Much like the time remaining display. If a unit didn't have it, how would it know when the correct time to end the song is? It ends when it ends. Much like a BPM display. There is no knowledge of what the BPM is supposed to be, therefore there is no adjustment necessary to make it 'correct.' It is what it is. What if a song had a time signature change in the middle of it? What if a song had a tempo change in the middle of it? What if a CD was just filled with spoken word, where there is no beat, how would it adjust it then? All of these questions I ask as a way to illustrate that a BPM display is not something that dictates how something is played by the machine, but rather it is a tool to assist a DJ with getting a halfway decent mix of two tunes.

Apologies for writing something not clearly and assuming you knew what I was talking about. The smooth transition is the DJ smoothly transitioning from one song to the next. At which time, two songs, from two different players, on two different CDs, most likely from two different artists, are playing simultaneously. This simultaneous playing of two different songs can go on for some time. Some of longest transitions I've done in the past have been 90 seconds long. If the music wasn't beatmatched appropriately, it would be a painful minute and a half to listen to. When it is matched properly, the listener may never tell that one song has ended and the other started, just that after a while they realize that the song has changed to a different one.

If you are not DJ beatmatching your music (playing two tracks at once), I see very little utility in having a BPM display. There was a box back in the 90s called the Beat Master that allowed you to hook two CD players (or any player of any media) to it and it would display the BPM of each. It did not communicate back to the players to tell them how to auto-adjust. It was up to the DJ to twiddle the pitch slider on each machine to match things up.

I feel I'm just emulating a broken record here and saying the same things over and over without contributing anything new. As such, I doubt I'll respond again - no matter how cleverly you bait me.

 

Thanks for all your help!

 

Then I still don't understand why my cd player can only play one track at a time, but has pitch/tempo control, and is supposed to have a auto BPM readout? What is the purpose for these features for one song only if it is always set to 0.0 or off?

 

You need two of these players (and a mixer) to play two tracks at a time. If set to off, or 0.0, there is indeed little point in having these features. The point is to enable you to adjust it as you see fit, if you so desire.

 

I decided to check the bpm more closely, on Virtual DJ, it has a bpm counter per bar. Now, for the song I looked at the bpm was 123bpm shown for the track at 0.0, but I counted every beat for the whole song and got somewhere around 176bpm.
For the first 15 seconds I counted 4 beats x 8 bars, which = 32 beats.
The song is 5:31 minutes long, if you divide 176 by 5.5 for (5:31) it gives 32, which is 8 x 4 (4 beats for 8 bars x the length of the track 5.5 = 176.
So, then the 123bpm read by the track, how can that be correct, or what is that showing exactly?
Even if you take the 8 bars times 4 beats it = 32 beats x 4 ( 15 seconds per minute) it is 128, so where does the 123bpm fit in as the tracks bpm read from the disc and any bpm website I look at says 123bpm also.

The song is "Enter Sandman" by Metallica.