One of my Apples is a referb and it's awesome. I'd buy another to save money in a heart beat.

Gustavo,
I'm interested in doing the same exact thing, so if you have success
or even get started doing this please post (or anyone else for that matter).

I don't have a mac either but have used a friends for a couple hours and I'm very impressed with mainstage. Unfortunately with the time I had I couldn't get mainstage to see the gi-20's. I know it's possible because after searching I noticed others using it correctly. This set up is something I'd like to try before spending all the dough. The possibilities seem endless with a midi foot controller, loops, all the mainstage sounds...
It's very exciting, yet overwhelming at the same time.
Leeland

Well, that would make two mono audio inputs and two MIDI stereo instruments. If not choosing the most CPU demanding instruments I think one of the strongest Macs could do it. My MacBook is a 2.2 GHz Core 2 Duo and it typically runs between fifty and sixty percent when doing either two audio channels with processing (stick) or MIDI input and some virtual instruments (EWI). I don't think my Macbook would be able to handle your scenario though.

Stereo in Mainstage (or Logic) is handled by first setting the audio channel strip to mono or stereo by clicking the mono or stereo symbol. If in mono this causes the channel to go stereo and if stereo it causes the channel to go mono. Pretty simple. Next stage is to select an input from a dropdown menu in the input slot. If set to stereo the physical audio interface inputs are presented as pairs: "1-2", "3-4" etc. For a dual audio input from a Stick you should use two mono channels. When set to mono the input field dropdown menu presents the same physical inputs as "1", "2", "3", "4" etc. Over here I use physical inputs 3 and 4 on a RME Fireface400 for the Stick's melody and bass side output.

Think about the signal routing in Logic or Mainstage as a mixer; mono inputs can be panned anywhere in the stereo field or send signal to stereo effects by an aux send knob. Then each effect processed channel comes back as an stereo effect return to be mixed into the stereo signal you send to the house PA. Effects can also be run directly on the channel strip, like insert jacks on a traditional mixer (typically the way to set up EQ and compression on each Stick side's signal).

For MIDI instruments there is no audio input (if not snagging one by the instrument plug-ins "Side-Chain" input slot) so you decide if you want a mono or stereo version when you launch an instrument in Mainstage or Logic.

Hello Per, as always your comments bring a lot of insight and save the rest of us of long hours experimenting. I am a couple of weeks away from going Mac, and will try getting the most performing MacBookPro available, I am blessed to have a wife with a student discount for apple that I will make the most of it, even better than the refurbished price.

I have tried the scenario you have suggested with a PC I have, through an M-Audio fast track pro (USB) interface, through Protools and launching separated software for soft-synths, which I guess they could have been opened as plug-ins from ProTools if the channel would have been created as a midi channel. The good news is that the whole thing worked, I was able to make the connexions work with the latency expected from my old laptop, but I was generating sound from my melody and bass side, along with one midi channel. I built this exactly as you suggested above, using ProTools as a "mixer", similar to what you suggest using Logic for.

Now, during some of the tunes I play, I change patch numbers constantly, for all four sources of sound, using a midi foot controller. I understand that you can change soft effects/synths from a common MIDI source assigning to each its own channel....but when they are used as plug-ins from a "host" software such as Logic or ProTools (or Live), how do you access the specific patches independently for each channel when playing live? Are the plug-ins contained by Logic somewhat listeners of specific Midi channels that would allow me to control real-time their config/patches from a Midi-foot-controller?

I believe the answers to the above must be yes, but the question came up when I saw your suggestion of using Logic as the main mixer. I thought, at the beginning, that I would open two instances of Guitar Rig for example, and assign to each its channel..... but that does not work, as when you open the second one you do not have access to the interface, as it is used by the first instance.

Leeland/Panther, I will get you posted as I go through the experience.

Thanks!

Regarding frequent change of patches:

In Logic you use the Channel Strip format as your saved patches. You may set up an effect chain for an audio input as a Channel Strip. For MIDI driven software instruments the instrument itself (synth or sampler) becomes part of the Channel Strip.

The trick to make your Channel Strips launch by external MIDI Program Change is to save them again as Performances. Hold down the mouse button on the top button in the Channel Strip Inspector and chose Save As Performance form the drop-down menu. As you save it you should assign it a MIDI Program Change number. To launch a Performance you have to send in the matching MIDI Program Change numer on MIDI channel 1.

Logic is not designed for live performance though, so the plugins of these performances are not pre loaded. They have to load as part of the patch change and that gives you one or two seconds waiting time with audio drop out as you change your live sound.

Mainstage is better then, because it preloads into RAM all plugins used by patches included in a concert as you open the concert. That ensures intant switch between sound patches as well as configurable reverb tail preservation of the old patch (set to a chosen number of seconds time).

Both applications use the same instruments and plugins and share the Channel Strip format. While Logic uses the Performances paradigm described above Mainstage adds some extra live goodies in parameter scaling, control of functions and layering of sound (multiple virtual instruments or multiple audio inputs layered).

Hello there, I am the blown-away owner of a MacBook Pro with Logic/MainStage since about one week ago, and just wanted to report some feedback. I am coming from an insane configuration of effects/synths/pre-amps and I can say, after only a couple of days, that I am in the way of migrating to a mac+interface only setup, I may need to give another week of tweaking and I will be there.

As Per generously explained, Mainstage (the "performing" software that comes with Logic Pro, the suite) allows you to run "Channel Strips" that are multi-channel patches that you change and all instruments/effects change instantaneously with it. My current setup is a M-Audio Fast Track Pro (USB) interface, a Roland GI-10 and a MacBook Pro running Snow Leopard 10.6.3, 2.8GHz Intel Core 2 Duo and 4GB RAM.

My Channel Strips change all 3 (and soon 4) instruments: the melody, bass and soft synth coming from the MIDI port from my Warr Guitar's Piezos + the GI-10, connected to the MIDI-in port on the M-Audio. The changes are instantaneous, and the sound is quite amazing. I change the Channel Strips with a FBC1010 (Foot midi controller), connected to the Midi-In port of the GI-10.

Knowing that I am going through a USB connection and I own a 10 year old GI-10 as Midi interface, I was expecting some latency, but if there is some, it is unnoticeable to me, there is no sense of delay between your fingers touch the string to the time you feel the sound.

I have not yet tried the loop controller (I have downloaded Mobius, but have not tried it or the one coming from Logic). I will add a note back here once I do. The only thing I tried that was not beyond my expectations was the sampler (EXS-24) which is one of the instruments available with Logic, that I have not been able to make it sound as my V-Synth (it does not harmonize the samples, the velocity changes with the pitch). If there are there any suggestions (I wonder, has anyone tried the one coming with Native Instruments, is their Komplete package a must?) I will always appreciate it.

I am planning to add a firewire connection, so I can run melody and melody-MIDI through a firewire interface, and bass and bass-midi through the USB interface, for a total of 4 channels running in unison on any Channel Strip. This will require another midi interface, I will see if I can get an Axon or something better than my old GI-10. Looking at how busy the machine is, with 3 channels running all sorts of sounds, it never went over 28% CPU utilization, and this with my wireless on, downloading all sorts of stuff, at the same time...

A final hint, my wife is getting some courses at a local university... which makes her eligible to get a student discount. I got the mac for 15% less of the price, and logic for 1/2 of it. I would suggest, for this prices and if you are interested on following this path, to find a family member that has access to some student rebate, the deal is even better than buying a refurbished machine. Thanks to this, it was possible to me to go 17 inches in this laptop.

It may be interesting having a separate forum for software-related setups, this (I believe, with the available technology) may be something to consider for the Stick/Warr player moving forward, given the great sound possibilities our instruments have.

Thank you all for the previous feedback offered here, which was instrumental for me to make this decision. This forum is great.

Regards,

I'm not sure what you mean by "harmonizing samples" and "velocity changing with pitch"? I do know though that you can set most functions in the EXS24 to scale values according to keyboard (= "pitch", ie note numbers; either going brighter or mellow with a scale direction) so maybe the issue you have is not with velocity but with a cut-off filter set to follow the keyboard?

I have the NI sampler Kontakt here as well if you want to ask about something in particular regarding that one.

Hello Per, thank you always for your feedback. I meant, I loaded a wav file that is, let's say 10 seconds long. When playing "C" for example, I would get the original wav file sound of 10 seconds, playing at a particular pitch. Once I play C#, I hear the sample played faster (now, let's say it plays at a higher pitch but it lasts 9 secs, it plays faster). A sampler should harmonize the sample, moving the pitch while keeping the length of the original sample. If I want now to play a chord, the thing is all over the place. I tried playing with the controls, without too much success. The sample I've used is a human voice singing something, so if you want two voices singing at unison, they should play both at the same speed, at different pitches. I may be doing something wrong with this sampler, have you tried doing something such as this?

Thanks much!!

Yep, I've done exactly what you're describing by using the Kontakt sampler. But I would rather call it time-stretching while pitch-shifting. EXS24 doesn't do the time-stretching, only the classic "sampler-style" pitch shift by shifting the rate (sample length altered by pitch change; great for harmonizing an organic sounding chord texture from a sample). Here's an audio example I recorded once for a magazine tutorial on time-stretch sampling technique with Kontakt 2. First the two raw vocal samples are presented acapella and for the rest of the clip they are played in harmonization with time-stretching activated:
http://www.box.net/shared/4yl5902efm