stereo chopping

_Stilo_ wrote:

Lumpy wrote:It doesn't have to do with auto detect. It has to do with how the segements are played and how sync is maintained between the sides.

Just when I thought I understood him..

I don't get your point. I can't see what's the problem to cut and play back the left and right channel at exactly the same sample, in case you chop equal. And there is no reason why the left and right chops would not have the same length in that case.

When you Extract parts from a stereo sample to a new sample, it ain't a problem either after all.

Do I miss something here?

Yeah I'm not following him either

_Stilo_ wrote:

Lumpy wrote:It doesn't have to do with auto detect. It has to do with how the segements are played and how sync is maintained between the sides.

Just when I thought I understood him..

I don't get your point. I can't see what's the problem to cut and play back the left and right channel at exactly the same sample, in case you chop equal. And there is no reason why the left and right chops would not have the same length in that case.

When you Extract parts from a stereo sample to a new sample, it ain't a problem either after all.

Do I miss something here?

You are missing something here.
To make it clearer.
Mono chop shop = easy.
Stereo chop shop = really hard.
Extract data (not =) Chopshop

Extracting data from a stereo sample is a totally different thing and is easy to do. All you are doing is changing the file length and copying the wanted data. This is totally different than a Chop shop or Rex or Acid file.

There is no problem as long as both sides of a stereo sample are chopped exactly the same.
But chopping them exactly the same would not be real useful in most stereo material lifted from records or CD or sample libraries where they do any panning.
If everything was panned center and you only had room ambience to the left and right it would be fine. It wouldn't sound any different than mono audio processed through a good stereo reverb but it would work.

But, if you have different beats on each channel, you will need different chop points for left and right sides that happen at different times.
This is where the problem is. You now have different clip lengths, that will have to be triggered at different times yet maintain sample accurate lock to avoid phasing of the center panned material.

A chopped or Rex'd or Acid format file is more like a playlist with a bunch of embedded audio clips than it is like a stereo sample.
It has to operate more like a disk recorder than a sampler to do this and many disk recorders will not maintain a sample acurate lock when you put different edit points in a dual mono file.
It sounds like a no brainer on the surface but there are a lot of technical reasons that make it very hard to accomplish.
I did hardware and software design some 20 years ago so I'm behind current DSP technology but I do know that our $60,000 Protolls rig can't maintain sample accurate sync when you put a mono file on two tracks and put edits at different points in each track.
This is esentially what would have to happen in a stereo chopshop file.

Is it clearer or muddier?

Lumpy wrote:

_Stilo_ wrote:

Lumpy wrote:It doesn't have to do with auto detect. It has to do with how the segements are played and how sync is maintained between the sides.

Just when I thought I understood him..

I don't get your point. I can't see what's the problem to cut and play back the left and right channel at exactly the same sample, in case you chop equal. And there is no reason why the left and right chops would not have the same length in that case.

When you Extract parts from a stereo sample to a new sample, it ain't a problem either after all.

Do I miss something here?

You are missing something here.
To make it clearer.
Mono chop shop = easy.
Stereo chop shop = really hard.
Extract data (not =) Chopshop

Extracting data from a stereo sample is a totally different thing and is easy to do. All you are doing is changing the file length and copying the wanted data. This is totally different than a Chop shop or Rex or Acid file.

There is no problem as long as both sides of a stereo sample are chopped exactly the same.
But chopping them exactly the same would not be real useful in most stereo material lifted from records or CD or sample libraries where they do any panning.
If everything was panned center and you only had room ambience to the left and right it would be fine. It wouldn't sound any different than mono audio processed through a good stereo reverb but it would work.

But, if you have different beats on each channel, you will need different chop points for left and right sides that happen at different times.
This is where the problem is. You now have different clip lengths, that will have to be triggered at different times yet maintain sample accurate lock to avoid phasing of the center panned material.

A chopped or Rex'd or Acid format file is more like a playlist with a bunch of embedded audio clips than it is like a stereo sample.
It has to operate more like a disk recorder than a sampler to do this and many disk recorders will not maintain a sample acurate lock when you put different edit points in a dual mono file.
It sounds like a no brainer on the surface but there are a lot of technical reasons that make it very hard to accomplish.
I did hardware and software design some 20 years ago so I'm behind current DSP technology but I do know that our $60,000 Protolls rig can't maintain sample accurate sync when you put a mono file on two tracks and put edits at different points in each track.
This is esentially what would have to happen in a stereo chopshop file.

Is it clearer or muddier?

I thought I understood ,but I admit I am lost.I'm sorry maybe you can post up a link with some audio and show me what your talking about I would love to hear this type of sample(two different drum tracks one left, one right). What I don't understand is why you would need to play the left or right at different times. That seems like it would take away the stereo phasing.I'm not sure about the programs your working with,but the mpc keeps everything exactly where it was chopped at.It keeps the same stereo phasing in the sample after you chop it. Both tracks(left and right) play back in sync just like they are expected to. There is no need to trigger the left channel separate from the right channel.

Lumpy wrote:You are missing something here.
To make it clearer.
Mono chop shop = easy.
Stereo chop shop = really hard.
Extract data (not =) Chopshop

I'm still not with you. Extracting data from a sample is exactly the same that is done when chopping the sample up in 8 or whatever equal parts, in my opinion. I don't know what magic you interpret into the ChopShop feature.

I can see that it matters when you detect the chop points differently for the left and right channel of a panned recording, automatic or not. But I really don't see the need to do that in most cases. After all, the two channels have to be in the same tempo/rhythm/sync anyway, so it must be possible to chop them together as well.

or at very least chop both based on the graphical data of the selected stereo field

_Stilo_ wrote:

Lumpy wrote:You are missing something here.
To make it clearer.
Mono chop shop = easy.
Stereo chop shop = really hard.
Extract data (not =) Chopshop

I'm still not with you. Extracting data from a sample is exactly the same that is done when chopping the sample up in 8 or whatever equal parts, in my opinion. I don't know what magic you interpret into the ChopShop feature.

I stated this above. It's no problem as long as the chop points are the same for the left and right side.
No magic, you don't seem to get what chop shop does or needs to be able to do to handle true stereo samples, meaning that there are different chop points for both the left and right side.

_Stilo_ wrote:I can see that it matters when you detect the chop points differently for the left and right channel of a panned recording, automatic or not. But I really don't see the need to do that in most cases. After all, the two channels have to be in the same tempo/rhythm/sync anyway, so it must be possible to chop them together as well.

Ah! you do get my point, you just don't need it to be true stereo in most cases is what you are saying. You want a stereo audio file with mono chops.

The orignal sound of course would be the same tempo and sync, the rhythm is not nessesarily the same from left to right in real stereo.
Here is an example 1/4 note pedal hat on the left, swinging 16th note ride cymbal right.
If the 1/4 notes line up perfectly or really close, and you chopped the swinging 1/16th notes on the right and 1/4 notes on the left, you in effect have 16 sound clips on the right and 4 on the left. pretend there is a long 808 kick in the center on the same 1/4 note as the pedal hat.
Now slow that 140bpm beat down to 90bpm (now the sync and the rhythm will be off, the tempo for both sides will be the same)
The problem is triggering those 16th notes to play sample accurate in sync with the 1/4 notes so as to keep Mr. 808kick from phasing.
Without pitch shifting or time stretching, parts of the 808kick sound will happen at different times between the two sides.
On the 1/4 note side it will be fine.
On the 16th note side the first 16th note will be good. The 2nd, 3rd and 4th notes will be late in reference to the left hand side (remeber we slowed the bpm down), causing the center material to be out of sync on the 2nd,3rd and 4th 16th notes. In this case it will be back in sync for the first 1/16th note in each beat but off on the other 3 between beats.

If the pedal hat and ride are less than hard panned it gets worse, more complex materiel even worse. This is the problem.

It's not that hard to understand.
I don't know how to describe it any clearer.

Lumpy wrote:Ah! you do get my point, you just don't need it to be true stereo in most cases is what you are saying. You want a stereo audio file with mono chops.

So what is true stereo to you? Each instrument panned hard to either one of the channels? If so, when did you last hear a record mastered like this?

If you want to put it that way, yes, I only need stereo files with mono chopping. Just like I would mix it down to Mono before, but preserving the "space" in the recording.

And that's all that can be expected from such a machine...it's not a 20.000$ dubbing studio after all. The "simple" way would work for most people and with most sampled records.

Sorry you had to write your ass off to make me understand

_Stilo_ wrote:

Lumpy wrote:Ah! you do get my point, you just don't need it to be true stereo in most cases is what you are saying. You want a stereo audio file with mono chops.

So what is true stereo to you? Each instrument panned hard to either one of the channels? If so, when did you last hear a record mastered like this?

A lot of album in the 60's and 70's, where I lift a lot of material had things hard panned in the mix. I last heard a record mastered like this yesterday.
True stereo is going to have things place throughout the stereo field mono chops in a stereo should be very do able for Akai, but I bet people would complain that it doesn't work well on a lot of material.

Lumpy wrote:A lot of album in the 60's and 70's, where I lift a lot of material had things hard panned in the mix. I last heard a record mastered like this yesterday.

Yea, I can only remember hearing 1 or 2 really like that before.

I'm still not sure I fully understand what you described, but I'm sure you know what you're talking about. I just can't picture it right now...

_Stilo_ wrote:

Lumpy wrote:A lot of album in the 60's and 70's, where I lift a lot of material had things hard panned in the mix. I last heard a record mastered like this yesterday.

Yea, I can only remember hearing 1 or 2 really like that before.

I'm still not sure I fully understand what you described, but I'm sure you know what you're talking about. I just can't picture it right now...

Most late 80's hip hop sampled old records which were recorded like this. Paul C (the pioneer of 'chop & pan') is famous for discovering this and using it on records like 'Give the drummer some'.