I’m getting some weird artifacts when trying to use sends in FMOD Studio. If I add a send to any track of an event, even without any affects to that send I get a kind of phase shift sound as I increase the signal to the send. To test whether or not there was something weird with my signal chain, I created a new event and tried with just the default Reverb send. If I bypass the Reverb effect or bring up the dry level in the effect, I get the same phased audio. If I enable the reverb but keep the dry signal at 0, it sounds fine. Any ideas why this would happen? I got the same behavior using FMOD 1.07 and 1.08. I’m on OSX 10.10.
Sends introduce a small amount of latency. (This feature is necessary in order to support certain types of routing, such as circular routing.) Because of this latency, playing a sent signal alongside the original signal at close to the same volume can result in audible phasing.
There’s a number of ways to avoid this phasing. One of the easiest to implement consists of having the same number of sends in each ‘branch’ of the signal path; The amount of latency introduced by a send is fixed, so as long as your ‘dry’ signal goes through as many sends as your ‘wet,’ there will be no audible phasing. (You will, of course, need to set the volume of whichever audio track or bus holds the new ‘dry’ send to -oo, and the send will have to be positioned pre-fader.)
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Thanks for that info.
Hi Joseph,
Can you tell me about other solutions to this issue that you know of? If I have to use prefader sends and set volumes to 0, then I can’t use bus groups in the mixer.
Thanks.
This solution does not prevent you from using bus groups in the mixer. Return tracks inside an event can be routed to the master track of that event, and so do not prevent the event from producing output; And return buses in the mixer can be routed into group buses without a problem.
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Cool, I’ll read up on routing a bit more as I’ve clearly misunderstood things a bit. Thanks.
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Hi Joseph, I stumbled upon this old thread as I’m running into the same problem. I think I’m misunderstanding.
I have a Track 1 with a send to Return A. That causes latency so I added pre fader -inf send to Return A. The -inf send is sent to a “void” track in the mixer that has it’s fader at -inf.
I still get phasing. What am I doing wrong here?
Hope you can help!
The latency added by a send affects the duplicate signal sent by that send to the return, not the signal passing through bus on which the send is located. As such, the send on the “Return A” track is adding latency to the silent duplicate signal sent to the “Void” return bus, and does not affect the latency of the signal passing through the “Return A” track in any way.
You have two routing paths whose signals you want to keep in-phase. To keep them in phase, each of those paths needs to contain the same number of sends. Currently, the path that leads to the output of the “Track 1” track and thence to the master bus passes through zero sends; the other path, that leads to the output of the “Return A” track, passes through one send.
To fix your event:
- Create a new return track in the event. For the purposes of these steps, I’ll call it “Return B.”
- Select the “Track 1” track, then add to its signal chain a pre-fader send targeting the “Return B” track. Set this send to 0 dB.
- Set the “Track 1” track’s volume fader to -oo dB. This ensures that the “Track 1” track produces no audible output.
- Delete the send targeting the “Void” bus. It does nothing.
If you follow these steps correctly, the “Track 1” track will produce no output of its own, yet the “Return A” and “Return B” tracks will output duplicate signals with the exact same amount of latency, and thus no phasing.
Riiight, okay thank you so much! I misunderstood 