FX Loop Latency?

[DJD100]

Anyone know what it is (probably around 6ms for the converters round trip, just guessing though)?

Thanks for any help.

 

[Jay Mitchell]

Anyone know what it is (probably around 6ms for the converters round trip, just guessing though)?

I've never measured it, but it won't be anything like 6ms. The basic latency in the primary chain is less than 1.5ms, and I would expect the extra conversions in the FX loop to come in something short of doubling that.

 

[Bakerman]

1.23ms

 

[DJD100]

Thanks guys!

1.23ms

 

[FractalAudio]

0.833 ms

 

[Bakerman]

Cliff, I checked the offset at output 1 L/R when one channel had gone through a cable in the loop. Just a synth square wave to test. The loop channel is delayed by 59 samples, 1.23 ms. Wouldn't that be considered the loop latency?

 

[DJD100]

Thanks.

My need is to time align a homemade tube amp in the fx loop to be used in parallel with the Axe amp models(s), in mono, and I've found that using the flanger set to 0.315 ms accomplishes this (not tested with a scope, rather it was tested via Pro Tools with the tube amp in the FX Loop and the parallel amp block/flanger panned out.

This seems to indicate that the amp block/flanger path has 0.518 ms latency (0.833 ms total loop latency) - (0.315 ms needed correction to time align my tube amp in the loop) = (0.518 ms)?

Also, is the flanger the best tool for this use and the phase reversal required by our tube amp (by best I mean the tool with the minimum CPU requirement)?

Thanks...

0.833 ms

 

[Bakerman]

The amp block does add about 0.5ms latency. Flanger doesn't add any to the dry signal until dry delay is turned up from 0ms. I'm still seeing 1.23ms added from the loop, have to set flanger to ~0.7ms to bring an amp signal in time w/ the loop-cable signal.