• We would like to remind our members that this is a privately owned, run and supported forum. You are here at the invitation and discretion of the owners. As such, rules and standards of conduct will be applied that help keep this forum functioning as the owners desire. These include, but are not limited to, removing content and even access to the forum.

    Please give yourself a refresher on the forum rules you agreed to follow when you signed up.

VG-99 + GP-10 USB Audio as digital source for Axe-Fx II XL+ over USB Audio (via DAW)


There are several threads here about failed attempts to use SPDIF to connect the VG-99/Axe-Fx II. Obviously, the different/locked sample rates proved to be an issue.

I’ve posted about this issue on several forums throughout the process of trying to find an answer and I think this now is the definitive solution. Thanks to all who helped. I’ve adjusted the content from other posts to reflect a final solution relevant to Axe-Fx II users...and I think this would also work for the III. If anybody wants to send me a III, I’d be more than happy to test it for you :D doesn’t hurt to dream...

After a lot of time addressing this problem I finally got a digital connection working (even at a 64 sample buffer setting) without pops n crackles -- and on 2 different computers. It's more or less reliable now. It’s also a very flexible guitar performance/recording rig.

I’m a macOS user (can’t speak on if this will work on Windows for now...maybe ASIO4ALL can help???) so the solution was to create an aggregate device in Audio MIDI Setup with the Axe-Fx II as the clock source and to activate ‘Drift Control’ for any other 44.1/48kHz devices.

On the USB hub connected to my computer (and following the order in the aggregate device):
1. Roland VG-99 (44.1kHz) Drift correction "ON"
2. Boss GP-10 (44.1kHz) Drift correction "ON"
3. Axe-Fx II XL+ (48kHz) Set as Clock Source — no Drift Correction (N.B. the Axe-Fx is set to USB Input mode)
4. iConnectAUDIO4+ Port 2 (48kHz) Drift correction "ON" (Port 1 is for the other device - iOS)
5. ATR2100-USB Mic (48kHz) Drift correction "ON"

My guitar runs into a Roland US-20 13-pin splitter box which allows [A / B / A+B] for using the the Roland VG-99 / Boss GP-10 in parallel. Setting up the aggregate this way should enable reamping on devices 1, 2 and 3. If reamping wasn't a concern, I would’ve just used analog connections. but I wanted to be able to access all functions fairly simply and quickly. I adjusted the buffers of the Roland/Boss devices to minimum individually in their respective driver interfaces under the macOS System Preferences. Also be careful with the USB Out levels — Axe-Fx is very sensitive to USB In levels and it’s easy to clip.

In Live 10 I can now route anything anywhere using ‘External Audio Effect’ devices (Axe-Fx) that are fed by the VG-99 or the GP-10. The conflicting sample rates seem to not be causing any problem at all at this time — thanks to macOS realtime sample rate conversion...but I wonder, what’s going to go wrong next?!?!?

Bear in mind that I use the Axe’s FX Loop function on a ‘broken grid’ in my patches to enable monitoring of the signal post DAW effects - this may or may not be relevant to other users. There are several software situations which can make this fail but I’ve gone into that elsewhere.

So, the end result is that this is now a viable way (with the assistance of a computer) to use your Roland/Boss V-guitar device to feed your Axe-Fx II digitally, record, reamp and make use of various DAW functions in real time. I hope somebody will find this information helpful.



Hello! I am very curious about your setup. I just purchased a VG-99 used over the weekend and already own a GP-10. I was looking at creative ways to hook both of these unit up digitally to interface with my Axe-Fx III and Apollo 8 audio interface but thought it would be impossible because of the 44.1/48kHz clash between VG-99 and Axe-Fx. So you use a USB hub (powered?) and let your Mac recognize all devices as audio devices, then create an aggregate device with all of them, setting the Axe as Clock Source, that's it?

It must be a bit of a headache to figure out what all the inputs/outputs correspond to from within your DAW though? Also I would be curious to see an example patch (or grid layout) in your Axe-Fx.



Related but not related sidetrack. I may have missed this in your post; but where is your normal pickup signal chain in this setup? Are you using all modeled guitars from the VG to feed everything?

I use the guitar out of my GR55 to feed the normal pickup signal to whatever modeler I am using at the given moment. If I end up getting a 1000; I am going to have to look into how I want to split the GK signal to multiple devices and how that will effect my normal guitar signal chain. Ugh.


Hi Joce, Jive Turkey,

My gear setups are always in flux and have significantly changed things even since I posted this back in September 2019. I'm always looking to optimize and simplify my workflow cos it's already too complicated! And it will certainly change again if (when...) I get my hands on the SY-1000.

So that device from last September was my 'Mega Aggregate' and I had all the hardware attached to an old iMac. But because I'm often moving gear to try things out in different configs, the aggregate would break when I removed a single device and then tried to run the incomplete aggregate device in Live 10. This resulted in crashes of Live 10 and messed up the channel name labels. This happens when not all ports of an aggregate device are present and available. I even tried making duplicate variations but that was a pain to manage as Live 10 would sometimes get confused about the port labels. What a headache it was! So I switched things up again for the sake of my sanity and split the whole 'Mega Aggregate' into two different rigs.

MOBILE MacBook Rig: GP-10* (8/2) + iPad SMUX (18/2)
DESKTOP iMac Rig: VG-99* (2/2) + Axe-Fx II (4/2) + iPad SMUX (18/2) + ATR2100-USB Mic (2/0)
*monitoring device

Technically, they can be run simultaneously with the US-20 but I found thinking about the VG/GP devices simultaneously takes more concentration power than I have available.

The same principles apply as before. You shouldn't need to worry about sample rates because coreaudio resamples on the fly. A powered hub is not necessary unless you have some USB devices that draw higher currents than the average USB port will handle. Roland/BOSS and Fractal devices are not in this category as they are mains powered.

I originally set the Axe-Fx II as the clock source in aggregate device 2 but have changed it to the VG for the new aggregate. I suggest trying both. You'll need to test your system for reliable performance.

The inputs in the DAW include a GK3 and a MAG pickup. I try to keep things conceptually similar between the VG-99 and GP-10. The GP-10 was meant to replace the VG-99 for live work as it is an ultra-portable and lightweight device and can be powered by a USB 5->9V adaptor (it only draws 300mA unlike the VG-99 which is much much higher and has a startup surge that the adaptor can't handle). In the VG-99, my patches typically have COSM guitar on path A and magnetic pickup on path B and I pan them hard L/R so I can assign each one as a dedicated mono input in the DAW. It's basically the same in the GP-10 but with slightly less flexibility as path B has to be Mag PU.

The DAW is the key to success. In Live 10 I use an External Audio Effect Device and funnel each path into the Axe-Fx II (USB input) -- these can be turned on/off via MIDI. If you're familiar with Live this will be self evident. I don't use other DAWs really...just Logic Pro X sometimes and I haven't been using it for months.

FWIW, I've taken to using amp sim/fx plugins in the mobile rig (no FAS gear) and have created effects racks (plugin chains) to replicate some of what the Axe-Fx does with good results. If my computer had a bit more grunt I'd probably go full VST for amp/fx sims and ditch the Axe-Fx but it really does sound that good and it significantly reduces the CPU load on the computer.

It's also important to keep in mind that the monitoring device in the desktop rig is the VG-99; not the Axe-Fx II. You will almost certainly have to do this if you have other non-guitar audio tracks in your DAW. That's talked about in other threads but basically, if the Axe-Fx II is in USB input mode and you use it as a monitoring device all incoming audio from your DAW goes to the grid and gets processed. Probably not what you want so the VG-99's outs are the destination for the master out of Live 10. Also, be aware of 'direct monitoring' in the VG/GP device or you will have problems.

It's hard to address everything here because there are many minor details to consider or things simply won't work well (e.g. perfecting USB audio levels and balancing COSM/mag signals come to mind straight up). It has taken a lot of time and effort to get this working properly and it's still work in progress. I guess a video outlining how it all integrates would be useful...maybe when my contract finishes.

And I haven't even mentioned the guitar synthesis side of things yet...

I'm happy to help with any specifics so feel free to PM me.


Thx for the reply! I guess it sounds like I will need to at least start experimenting a bit and see if (where) I get stuck.

I'll post back here if I make any progress!

Top Bottom