Originally Posted by DanRand
No. In fact the ES-4 will probably get it's SPDIF encoded audio/data slightly earlier than than audio going through your DACS from your DAW. My ES-4 gets it's data 20 samples earlier than audio coming out of my analogue outputs.
All MIDI and Din Sync devices have latency. For MIDI devices this latency is the time the MIDI device takes to spit out audio in response to a MIDI note on message. My Waldorf Pulse takes around 2.5 ms to respond to a MIDI note on message. My 303 takes about 3-3.5 ms to respond to a Din Sync/Clock Pulse. This means I need to delay the audio coming from the Pulse by 1.5-2 ms so that it lines up exactly with audio from my 303.
The latency I was referring to was for software monitoring only. If you're software monitoring you have output latency (DAW to ES-4) + synth/device latency + input latency (the audio coming from device/synth triggered by the ES-4 going into your ADCs) + output latency again (final monitoring). That's one whole round-trip more than audio coming straight from your DAWs soft synths etc.
My point was you can safely line up your synths at your DAWs inputs using a combination of MIDI track delays and then fine tune with a Sample Delay plugin. Of course, to be this precise you'll need to figure out the average latency of your synths!
Originally Posted by chrisso
To be honest, I don't really understand any of the above.
I use an ES4 with Ableton, Logic and Pro Tools.
I send on an SPDIF output (from UA Apollo).
I record my hardware synths being controlled by the ES4 and everything is perfectly in time. Much better than midi.
I combine hardware modular with software instruments such as Maschine, Kontakt and Massive.
Using the ES4 I never have to retime my hardware.
There are YouTube videos showing how to use an ES4 in various DAWs.
Like I said, the round-trip compensation is for software monitoring. If you're hardware or direct monitoring you don't need to compensate for an extra round-trip, but you do need to take account of the lower latency of the ES-4's SPDIF stream (usually) and the response time (note-on latency) of your hardware synths (if you're trying to be as precise as possible).
If you're software monitoring
synths triggered by the ES-4, you need to send the MIDI/Sync one round-trip earlier. Think about it, the data to the ES-4 arrives at roughly the same time as other audio at the same position on your DAWs timing grid. Software monitoring a synth triggered by the ES-4 means you have to compensate for the synths/device's latency, come into your DAW (ADC & input buffer latency) and come back out again (DAC latency & output buffer latency). That's one extra round-trip due to software monitoring synths triggered by the ES-4.
There is no extra latency added by the ES-4 that I know of. Also, unless, you state how you intend to monitor your external synths, I can't say whether or not you'll incur this extra round-trip caused by using the ES-4 with software monitoring.
So this all boils down to how you monitor your synths. I like the flexibility of software monitoring so I have to put up with another round-trip. For example, my Pulse has a negative track delay of -13.0 ms; I then use a Sample/Buffer Delay to delay my Pulse's audio by 6 samples (to fine tune) at the inputs to the DAW so that it lines up with all my other gear.