3 replies to this topic

[dduncan4@san.rr.com]

Have run a Smaart on an ITec 4000 (Amp Input to Amp Output) the delay in the low end (60 Hz) keeps moving by as much as a foot. The curve levels keep jumping up and down.

Tested Smaart on a 5002 with PIP and everything was good. Same delay every time, levels the same every time. What frequency do they run at?

Is the fact that this is a switched output device messing with Smaart?

Why is this amp doing this?

This is not the only 4000 we have, and we have 6000's too, they do the same thing.

[DGlass]

I don't have an answer on that one right now but I have passed it along to be looked at. Stay tuned...............

[Bradford Benn]

We have used Smaart with I-Tech succesfully without the problems your are indicating. However we are not experts in Smaart and can not assist with the troubleshooting of settings within Smaart. The I-Tech family has a fixed latency.

DSP Processing: 32 bit, Floating Point, 665 ?s latency.
DAC Conversion: 24 bit, 135 ?s latency.
ADC Conversion: 18 bit, 312 ?s latency.

The amplifiers themselves switch at 250 Megahertz or 200 Megahertz depending on the model, still well outside the range of impact at 60Hz.

The first item I would recommend checking is that there is no high pass filter active on either the test microphone or the amplifier.  Also given that a 60Hz wave is about 18' 9" long the one foot variation is within 5% which may be within the range of accuracy depending on your settings.

[dduncan4@san.rr.com]

This measurment was from input to output of the amp, no mics. Yes there is a high pass in the amp at 32 Hz with 18 db of slope. Will try removing it and then test again. Now dumb question why would a high pass affect delay?   The 5002 pip has a high pass at the same freq/slope.