Logic Pro 9 (and then Logic Express 9) indeed works perfectly on a PowerPC mac (universal binary application). Moreover it seems performing ways better than Logic 8 (by using more efficiently distributed load accross CPU cores), so running it on a G4 shouldn’t be a problem :
For the record, LP9 is up and running on my G5 Quad. While I’ve yet to fully test functionality or Mainstage 2 fort hat matter, I can say that the upgrade process ran smoothly.
I’m editing a large project at the moment and I’ve not yet run into any issues. One thing I can say is that all 4 processors in my Quad seem to be better utilized than under LP8. Load looks very evenly distributed.
PPC and Logic 9 works…trust me. I’m running it right now– and I’ve worked on three large projects just today.
In terms of MASSIVE performance improvements; I’m a bit stumped. My G5 Quad is running at about half CPU in a plugin intensive session containing about 46 tracks (32 MIDI). Disk I/O load is also about nill. Memory is at about 75% utilization.
UPDATE : as stated through below links, Logic Express is Intel binary only starting 9.1.1 update (the updates won’t apply on PowerPC).
Cjed Audio 
The Logic Express What’s new section features a picture of Space Designer. However in Garageband to Logic Express page the pictures featuring Space Designer (and Delay Designer and EVD6) are titled with Logic Studio.
This is misleading information (error in site layout ?), as it would be logical that Express 9 do not include (LE8 didn’t) the advanced plugins like Space Designer (we however already know that it doesn’t include Sculpture).
Despite various informations (here and there) about Logic 9 not working on PPC (or at least only on G5 – not on G4), we can find a procedure to install it on a PPC.
Hi, I have tried installing Logic 9 on my PPC Quad MAC OS X 10.5.8 and cannot get around it. Is there a way to modify the install procedure?
A fix for Logic Pro 9 crashing at startup can be found here.
all my plugs are asking to be updated please help if anyone has experienced this problem
Cannot check for now, but strange as I read that the update went smoothely for most users, and that the new version even seem to don’t have to check the plugins again. Moreover most plugins seem compatible. What plugins are concerned ?
Mainstage and Mac G5 dual 2 gig 2.5 gigs Ram
Not 2 bad, running GSI VB3 at concert level, 4Front True Pianos and Omnisphere. Big problem however is that in layout mode it usually crashes when adding a component to the layout, … not always per se, but always when trying to add a patch selector… also Playback metronome does not sync to the MS2 clock. Etc… thoughts?
I also found that adding to the layout crashes Mainstage 2 on a PPC Dual 2.5 Ghz G5. I’ve had some luck adding object to a premade concert template that has lots of objects. The one thing I did notice was the tap tempo doesn’t work right at all!
i bought logic 9 ’cause i saw a vid running l9 on a g5. Works fine but Mainstage crashes if i only ‘look’ at the patch library. Any ideas?
Moreover it seems more and more likely that the Express version doesn’t include Space Designer and Delay Designer (and only provides a limited version of Multipressor), nor supports surround, nor includes EVP88, EVB3, EVD6 and Sculpture instruments.
I’m glad I stumble across this post, I’ve got LP9 on my macbook pro, and now I can put it on my G5 Imac. Thanks!
Take a minute to vote for you primary DAW @
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I have a PPC G5 dual 2.7 cpu. I Dual boot either into Tiger 10.4.6 Or Leopard 10.5.8 I currently Run Logic 8 mirrored in both OS’s but I have special plugins that work only in Tiger for LP 8. My question is can I install L9 in the same way and expect it to work in Tiger and Leopard ?
I have ppc G5 dual core 2.2 and
Wanna run logic pro 9, would it work pliz help.