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Sujet Virtual DJ 8 BPM issue - Page: 2

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SerinePRO InfinityMember since 2013
Just in case it is useful:
This image shows a typical attempt at automatic detection of a beat grid. As you can probably imagine, the first beat is actually where you can see the beat. What it's actually selected is a piece of vocal sample.

This second image shows the eighth "beat" in the image which might be what it's trying to detect in this track, except it's not detected that well either.

I'm really happy to help with this however I can - maybe it's just a small number of PC's and that's where the problem has arisen.

Posté Mon 09 Jan 17 @ 10:51 pm
groovindj wrote :
Andy7689 wrote :
old Stax and Motown songs
you are never going to be trying to beat match them

Actually it's not beyond reach!

As far as I know, no DJ software does it yet, but Ableton Live can "warp" old tracks like that and correct (straighten) the BPM, making it possible to beat mix them, add your own touches (a bit more percussion or a more modern beat) and so on.

Yeah I guess its possible, but the "keep the faith brigade" would stone you if you messed with their tracks like that. Not playing them on vinyl is bad enough for them lot. :)

Posté Mon 09 Jan 17 @ 11:42 pm
Djratedxxx919 wrote :
Hey fellas, thats what beat tap is for. If the bpm is correct, just nudge the downbeat or where you want it to be considered the beginning,
to the cursor line hit beat tap and it will set the first beat putting the beat counter in phase with the track. If the bpm is wrong just tap the beat in.

I'm glad I came across this post! I have to adjust the CBG on most tracks and to be honest I just accepted doing it as part of preparing my music. For example when I add cue points, edit track info etc I adjust the CBG if it needs adjusting.
I never knew about using the TAP button to set the first beat marker. I've just tried it and it works brilliantly! I will say though that as much as I don't really mind adjusting the CBG manually, I do agree that it would appear the beat detection engine could do with tweaking.

Posté Tue 10 Jan 17 @ 2:25 am
So anyway, I know the 'BPM keeper' / 'counter' whatever you want to call it isn't essential and you should be able to mix without it, that's not the point... I paid a lot of money for the full Virtual DJ license and I would expect to see it working! VDJ 7 never had any issues. I think whoever creates the software needs to go and have a hard long think about considering to fix it and make it more accurate. This isn't just an issue for me, it seems to be a common thing. It's a real shame that nothing is being done to correct it!

I know how to mix without being dependant on software, but I also know that such a big company and worldwide-used software should be on top of it and be making sure that it fully works. I've moved back down to VDJ 7 as I like ALL my things to be working. I like to be able to see the beats of the bar an make sure my timing is correct. I might start a petition for VDJ to sort out the issue with VDJ 8's BPM keeper as I can't see anything being done for the handful (seems to be quite a large handful as well) of people who have the same issue.

Not happy at all. I would even pay extra just to have the BPM keeper fixed and made more accurate. At LEAST 40% of my songs are incorrect in terms of the BPM keeper. Something seriously needs to be done. I hope this is sorted out.

Posté Thu 12 Jan 17 @ 5:24 pm
AdionPRO InfinityCTOMember since 2006
Please share some track titles.
In most tests over many different genres VDJ 8's detection is better than VDJ 7's.

Posté Thu 12 Jan 17 @ 9:09 pm
Andy7689 wrote :
the "keep the faith brigade" would stone you

Possibly true if you overdid the additional percussion or added bass drum etc - but just warping the track without doing anything else, they would have to be pretty special to notice that the BPM was no longer varying. I've done a few over the years and no one has ever noticed the difference when I've played them.

Posté Thu 12 Jan 17 @ 9:58 pm
Can someone leave a youtube video how to adjust the CBG manually with like 2 or 3 song examples. I would really appreciate it and I bet some people are actually reading this thread and would be interested at how to do this. I am a visual person and like to see how to do these things. I am so involved with keeping the events going that I don't get to enjoy the mixing as much as many people and let virtual dj do everything it can for me and if it's not doing it right and the good ears in the audience notice it, it's not good for us.

Adion would like some samples that he can test on his own and I hope people can provide them so we can see what's happening.


Posté Thu 12 Jan 17 @ 10:37 pm
SerinePRO InfinityMember since 2013
Youtube examples
Sultan of Swing (Rodway Remix)
Sphynx (Eggchan Remix)


Select a track and play it
Right click the BPM to bring up the BPM editor
Expand the editor to full screen.
Listen to the track and note where the beats are falling.
Zoom right in on the red "first beat" marker. You will probably see immediately if it is a little off, but you will have to listen to that portion of the track to see if it is out by a whole beat.

When you have decided where the first beat in the track is, move the marker to this point. Zoom right in as for most tracks you can visually detect the start of the beat with great accuracy.

Once you've done this a lot you will find it quite easy to pick the right point. You can also find a non-first beat and then use the nudge arrows (Bottom right) to move the marker from this point to the correct point.

Finally, check the end of the song to ensure that the grid lines up nicely with the beats here too. In the case of example 1 a slight adjustment made it line up better and coincidentally brought the BPM to 140.000 BPM

Video 2 is just a second example of the same process.

Posté Fri 13 Jan 17 @ 4:31 pm
SerinePRO InfinityMember since 2013

You can see a browser view export of some tracks in my library which all almost certainly have bad detections (all the songs I like have already been manually adjusted, I haven't listened to many of these). As I said above, probably the majority of tracks in my library have an unusable detection, and probably 80-90% need a manual adjustment for the sync feature to sound good.

If you want the MP3 files or would like to discuss it in more detail, as I stated before, I would be very happy to do that. Clearly your experience and mine are different, perhaps that is something to do with my hardware but obviously this isn't just affecting me and I think we would all benefit from it being fixed :) Thank you for looking into this :)

Posté Fri 13 Jan 17 @ 4:44 pm
Some of the comments made here seem to be assuming that computer beat detection is an exact science. It is not.

What does 1/1000 of beat per minute mean? Probably nothing at all and just part of the slop in the calculations.

For that matter, hundreds of a beat per minute can be meaningless as well. Sometimes 2 different programs will come up with the exact same beat to the hundreds position but not that often when analyzing a variety of songs.

I don't know these things like you do but to me it is an interesting subject and I have to do a lot of research on it so I know something about it from a numbers point of view.

Most beat detection algorithms use a range to do the analysis. like 60 BPM to 180 BPM. This helps the algorithm narrow it down within the range. Typically if the BPM falls outside of this range then it will be automatically doubled or halved. The range for VDJ seems to be around 85 to 160. Some programs allow you to set this range.

The beat detection code tries to find the predominate BPM in a file. Now given that, where is the first beat? Sometimes easy to get it right and sometimes not.

How does VDJ stack up against other programs doing beat detection? Just the BPM detection itself. I think it does favorably well but think it could do better but I know it is not easy. Any tweaking at all can mean something else can be off. There is a lot of on going research for it still.

Doing it by ear seems to be the best way to do it and the more experienced DJ's say this over and over. I am curious on how long it might take for you to learn to do this where it becomes more or less automatic for you.

Good luck when you are trying to compare any BPM detection program to what the human ear can detect. My opinion just as a listener has to be humans have no concept of what 1/100th of a beat per minute might mean and is probably not even noticeable no matter what for your use case. The guys who do it by ear are not thinking in those terms for sure I would think and the people out there listening could not even notice it.

Posté Mon 16 Jan 17 @ 5:22 pm
Well said, Don.

People need to remember that DJs have been mixing successfully for many decades, long before all these fancy addons such as waveforms, BPM detection, beat grids, sync and so on.

With vinyl, you just had the record and the deck. That's it. You mixed it with the next one by listening and adjusting the pitch fader.

Some people timed the BPM with a clicker and a stopwatch. You got a whole number. It wasn't a precise enough method to get fractions of BPMs - and it didn't matter.

Electronic BPM counters started to appear on some mixers, or as standalone devices. They gave you a whole number. One digit after the decimal if you were lucky.

Making a fuss over 0.007 of a BPM is ridiculous. How long would that take to drift out of sync with a track that was an exact BPM? Probably far longer than you'd ever need to segue from one track to the other. And..........if you hear it drifting, correct it yourself manually. You're a DJ.

Posté Mon 16 Jan 17 @ 5:55 pm
Kids are lazy now n days........

Count the the beat for 15 seconds then times that number by 4.

Simple mathematics and it shouldn't take long at all.

But with that being said VDJ not finding the first beat is a problem and needs to be looked at.

Posté Mon 16 Jan 17 @ 6:01 pm
SerinePRO InfinityMember since 2013
Being off by a few thousandths? Fine, completely forgiveable. Not complaining, as I've said at least twice in this thread I think VDJ is a masterpiece of software. I'm reporting that issue because it's easy to fix and I want to help make a great piece of software unstoppable.

Inability to detect when the first beat in the song is? The feature is not fit for purpose. That is what I think the focus of the thread is. As I've also said twice, I am aware that "real DJ's" don't need this. As I have also said before in this thread, I am not a "real DJ". I am a customer/user of VDJ software that is offering feedback to improve the software on a feature that I would like to use.

I listen to music in automix a lot while I work so the automatic detection is arguably more important for me than it is for people who are fully focused on mixing songs. There are other potential VDJ customers who are relying on it to mix and I know that "real DJs" are holier than though but at the end of the day these are people with money and I expect that VDJ Inc would like to be able to sell them the software.

I don't want to start another argument about whether it's ok to use a sync button but I think you are wholly missing the point Don. As to your last point, when I used Traktor in the past, its beat detection was considerably better and it successfully detected the first beat 95+% of the time.

Posté Mon 16 Jan 17 @ 6:29 pm
Don Moir wrote :
Some of the comments made here seem to be assuming that computer beat detection is an exact science. It is not.

Doing it by ear seems to be the best way to do it and the more experienced DJ's say this over and over. I am curious on how long it might take for you to learn to do this where it becomes more or less automatic for you.

Good luck when you are trying to compare any BPM detection program to what the human ear can detect. My opinion just as a listener has to be humans have no concept of what 1/100th of a beat per minute might mean and is probably not even noticeable no matter what for your use case. The guys who do it by ear are not thinking in those terms for sure I would think and the people out there listening could not even notice it.

Regarding BPM detection (not grid or phase) the truth is very simple:
For tracks with a steady tempo computer software can get a far more accurate result than human ear, or get it completely wrong.

The "main" issue with BPM detection algorithms is to determine the music signature of a given track.
That's where computers will through the BPM off (however most of the time the true BPM is 0.75x or 1.25x of the detected value besides the typical half/double BPM values)
When the algorithm can detect the music signature, the rest of the process is very easy and accurate. Far more accurate than human ear.

Grid and phase detection are a completely different animal though.
Grid detection can be thrown off a few ms depending on the baseline of the track. When the phase is not thrown off for more than 4ms then everything is good since the difference can't be interpreted by the human ear.
For phase detection the main problem is the "music" itself. There's no rule for the "primary" beat placement. Not to mention that a lot of modern tracks (and in some genres almost all tracks) feature changes of the primary beat one or several times within the track ( like 1,2,3,4,1,2,3,4,1,2,1,2,3,4,1...)
Therefore there's no specific rule you can follow in order to locate the primary beat efficiently on all tracks. Some "guessing" is needed depending on confidence levels and other statistics.

Posté Mon 16 Jan 17 @ 6:32 pm
locodogPRO InfinityModeratorMember since 2013
I know that beat detection isn't an exact science, but without bring up tracks where it goes wrong it won't improve any further, tbh honest some of my genre's of choice are a greater test for it [footwork, breakcore, speedcore] compared to straight 4/4 And to be fair to atomix I can only recall maybe 2 fixed tempo tracks being the [entirely] wrong bpm since v8 came out, correct bpm out of phase is also very rare. Correct bpm on beat but out of phrase was pretty regular [at least with jungle et al] but it's got better.

Auto pitch match I use all the time, sync very very rarely, but with my new idea for quantized delayed start means the first beat being right, has become more important

Posté Mon 16 Jan 17 @ 6:38 pm
SerinePRO InfinityMember since 2013
I agree with you there phantom, the tempo detection by virtual DJ (apart from the .007 errors and similar) is usually stunningly accurate. I can't believe how good this is. I have corrected maybe 2 tracks in a library of 2000.

But there is no(?*) excuse for the "first beat" marker being placed before the beginning of the song or during a period of near silence 300ms before the first beat.

*actually there is probably a really good excuse that I'm not aware of, but again I want this to be a contribution, constructive criticism, rather than being considered a moaning noob. I bought the software without this feature and that's fine - I thought it wasn't supposed to work. But if it is then.. well, here we are. I have provided many examples and can easily provide hundreds more.

Locodog I saw your idea for quantized delayed hotcue start and that's another cool feature that DJs don't "need" but could be awesome to have. Certainly I would enjoy it.

Posté Mon 16 Jan 17 @ 6:54 pm
Can I just say that I am laughing very hard at this thread. I know that there are a great many people using this software, and want everything. As Groovindj stated above, all this technology is crazy. The first beat is where I say the first beat is, whether the software gets it right or not, and most of the time it does. Nothing is perfect, does it have to be? All this scratching (technical stuff), is making me itch. Calculating the BPM to the hundreds or thousands point? Really? I guest it's important to some, and if that's what you want or need, who am I to stop you. But I'm telling you, this is hilarious.

Posté Mon 16 Jan 17 @ 7:09 pm
Now experienced DJ's seam to say mix by ear and you know where the first beat is etc. What about automatic beat detection? Speech recognition was once thought impossible but some break thrus were made which makes it a reasonable thing to do these days.

I did not want to try to put everything on my mind into one post. Part of the reason for me posting on this is to learn more about it.

First I know how to dance and love doing it. That is my first notion of beat. If a song is at 160 beats per minute, it can be hard to tap your foot at 2.6667 beats per second but the reality is it does not matter. I think I am thinking in seconds when dancing to a beat. Maybe a span of about 3 to 5 seconds. When dancing you have arms and legs and the rest of your body to keep in time with the music.

The easy cases for automatic beat detection are well fairly easy and should be accurate in these cases. I have been studying this on and off over a period of years and have been thru at least 10 different algorithms and probably more with lots of study. When I first started doing it, I could see the easy cases were easy so I did not bother with them much and still don't much care about that part. I have been more interested in the hard cases and variable BPM. A whole lot of music has variable BPM and to me the only way to get pure accuracy if such a notion can exist. Constant tempo should not be a problem but even then there are intro's and exits that can throw automatic detection off.

One notion I had just from an intuitive stand point is I think I also believe pitch is better then sync for matching but I can't say for sure on that and it is not the only story. I find that sync can be to abrupt for my taste but then that is just an observation and not much else at this point for me.

When I used to live in Dallas, there was a club that stopped serving alcohol at 2am but kept the music playing non stop till 4am and yeah I was there on occasion. Every song blended seamlessly into the next with same or close tempo and each song had constant tempo within itself. So I think an easy mix for the DJ or even automated. Either way it sounded great.

I have also noticed the first beat being off and can be quite a bit. Better I think to break this down into components to see if solutions can be made available in VDJ for those that think the only way out is automated. I had a young guy doing some work at my house and he insisted on using a drill to unscrew screws. That can be quite effective of course but in this case it was not. He did not seam to have much of a notion on how to use a manual screw driver and was taking too much time messing with the drill and I told him that. I can't quite remember but after wasting his time I think he did pick up a regular screw driver. You should have more than one tool in your box.

Posté Mon 16 Jan 17 @ 7:33 pm
On the subject of variable BPMs (a lot of the music I love is pre drum machine), I do wish VDJ had an option to display a live BPM rather than just the one fixed BPM it worked out from an average of the track.

Luckily I do have external hardware that can show a live BPM (the Red Sound Micro BPM) but it would be far easier to have it on screen.

Posté Mon 16 Jan 17 @ 7:44 pm
Been asking for this since 2008 @Groovin. Never give up hope ........

In BPM Studio you just right clicked the BPM reading to swap between scanned and live. So simple but Atomix have never been interested in this feature.

I know a few people who would like this, and it would be great for me working in an 80s club at present.

Posté Mon 16 Jan 17 @ 8:04 pm
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