using external spring reverb

[therecordinghouse]

i am using an akg bx10 spring reverb with my 002r le setup. i have it set up on an aux track as an insert (analog ch 7-8). i command click to see how many samples of delay are introduced. i noticed it stays at 6 samples no matter what buffer size i use. is this right? i thought that using a larger buffer size would introduce more delay than that.

[tele_player]

You should test the delay yourself, the delay reported by cmd-click isn't telling you the whole story.

I just tested this on my Mbox 2 Pro, 7.1.2, running an I/O insert through Analog 4. The delay is always reported as 6, but the actual delay is approximately ((buffer size x 2) + 230)

This makes sense, since the delay will be caused by the buffer on output, the buffer on input, plus the delay for the A/D/A conversion plus FW delay.

ProTools LE doesn't really measure the delays. The delay reported on the track is the sum of the delays reported by the plugins inserted on the track. I don't know if the value 6 is correct for the hardware insert plugin, but it's so greatly exceeded by the actual delay that it doesn't matter.

[therecordinghouse]

that makes me sad.

[tele_player]

Note: the above test was done at 44.1k. I just tested it again at 96 k, and the formula is approximately ((buffer size x 2) + 400). My tests are approximate, that constant might not be quite correct, but my conclusion is that the delay is comprised of the buffer delay, plus the delay for A/D/A and FW, which depend on sample rate.

ProTools' I/O plugin could be fixed so that the delay reported on an I/O plugin adjusts itself for the known delays - buffer size, A/D/A and Firewire, but actually measuring the delay through whatever's plugged into that I/O would be much trickier.