Midi Timing Issues - Logic 6.4 On G4 With Jv1080 Options

[bradders]

Hi
I need some help. First of all i am not vastly experienced with Logic.

I'm running logic pro 6.4 on my G4 with a jv1080 connected with a 2x2 midisport usb using the latest drivers.
I do quite a lot of arranging and often have several midi tracks running at once (often the full 16). I usually enter each track using the matrix editor and quantize them afterwards.

The problem I have is when i play back the song. There is often a lot of time delays and the problem is worse the more midi tracks I use. It's as if logic can't cope dealing with so many midi commands simultaneously. If I mute some tracks the timing improves. But anything above 2 or 3 tracks starts to cause some timing problems. Surely my G4 is powerful enough to deal with this. Atari managed it decades ago.

I suspect that it's a setting somewhere on the JV. But I haven't got a clue with this machine. It's got a techno sound card inside of which some of the sounds are sampled loops. When I play these sounds without the G4 on they work fine but when i play them with the sound selected from within logic the different elements of the sampled loop seem to play out of sync with one another. I don't know if this problem is related but thought I'd mention it just in case.

It's as if logic is somehow affecting the JV in some way at least.

Look forward to a response from someone with the knowledge.

Cheers
Brad

[lepetitmartien]

Are the pieces really busy with notes?
Are you sure the midisport sends/received a clean MIDI signal?
Are there other USB peripherals save keyboard/mouse/logic key?
How is the midisport attached to the mac? Directly, thru a hub… ?

[bradders]

The pieces are not overly busy with notes. Usually/typically consists of a basic drum beat with numerous repeated bars plus a few fills, a fairly rhythmic bass line, piano part and usually some simple wind and string parts for a school to play (often sustained notes). Its not as if everybody's playing thousands of semiquavers.

The midisport is connnected to one of the main usb ports on rear of G4. No other usb peripherals. G4 has an audiowerk PCI card.

I don't know how to be sure midisport is sending/receiving clean midi signal.

Cheers, B.

[lepetitmartien]

My personal solution is to hook up a Nord Modular to a supposed noisy interface. If it's noisy, the modular will behave strangely… A friend had a now old m-audio interface which could play note with noise all by itself

It can't be the busyness of the track, so:

- Noise (I've never had to look after that save with Nord Modular which are s…s for the quality of the MIDI signal, maybe there's a way to record the output and compare).
- Something in the USB, not peripherals but the ports… try to move the plug to the other port (ideal would be a USB PCI card to check thru it)
- Something fishy in software, though I don't see why…
- the cables, have you checked them?

Does the problem just came in? Or is it nothing new?
If it's a newcomer, i'd look after the drivers…

[bradders]

Ok.

I've bought some high quality midi leads - it's not that, it's still doing it.

I've swapped USB cables - it's not that, it's still doing it.

There was one slightly newer version of the driver - it's not that, it's still doing it.

I've used every USB port available (both main and additional USB pci card) - it's not that, it's still doing it.

The only thing I haven't tried is changing the interface itself which I admit i did buy 2nd hand on ebay. But i seem to remember that it used to happen on my old beige G3 with a serial midi interface and with an older version of logic.

I know nothing really about the environment. I want to be sure that I've set up all the midi connections properly in that. When i changed versions of logic i simply copied the environment setup from the old version. Therefore it still has things like 'printer port' in it even though my G4 doesn't have a serial printer port. I seem to have 2 midi setup pages currently in the environment.

Many thanks, Brad.

[hazeltine]

i did have the same problem as you ages ago using a midisport 2x2. it just started behaving very badly in a similar way and i stopped using it after that. sorry i don't have a fix to offer, but just letting you know the same happened to me and another person i know. if you can i would try another midi interface.

[lepetitmartien]

I've had first hand experiences from serial versions, not the USB ones though we have some people regularly here with unsolvable problems…

If it doesn't get better thru cable swapping or software twiddling…

On the M-audio drivers, we know the guy in charge now, if he can make things better he can (and he did). How old are the available drivers? Just in case… He's in charge for a year now and the first made right drivers are only coming out now.

[Metro SE]

The easy way to determine if it is the interface is simply to try a different DAW!

[bradders]

What's a DAW?

[Metro SE]

DAW = Digital Audio Workstation software, e.g Metro, Logic, Performer, Cubase, etc, etc,
Some of these programs have demos so you do not need to purchase anything.

Ce message a été modifié par Metro SE - mar. 4 oct. 2005, 00:03.