First of all, thanks again to John and the forum members for promoting and assisting in the use of this amazing tool. I have learned so much about acoustics and measurements just from trying things out, and it's great to know that there's always a measurement to analyze what my equipment is doing.
I recently bought a used Behringer DSP8024 mostly to play with and possibly use in a secondary system. It was a fraction of the price of a new miniDSP so if it turns out to be unsuitable, no big deal. But having it in my hands, I wanted to characterize its performance so I could proceed from a position of knowledge. The distortion and noise from this device turn out to be entirely acceptable for my needs. It has a delay setting which I'm sure will also help - but as a matter of course, I wanted to see what the native delay of the processor is. I set up my Scarlett 2i2 to measure both a loopback path and the DSP8024 using loopback as timing reference, and compared impulse responses. The mdat file is attached.
I see an approximately 1.7 ms difference between the two measurements. My (probably naive) questions: (1) where is the common 30+ ms delay coming from? Is that the delay from output through REW and then back into the measurement portion of the software? I had assumed that the use of a timing reference would account for that delay, but either it doesn't, or I'm not using it right. (2) is it correct that the difference between these measurements is the actual DSP8024 propagation delay?
I recently bought a used Behringer DSP8024 mostly to play with and possibly use in a secondary system. It was a fraction of the price of a new miniDSP so if it turns out to be unsuitable, no big deal. But having it in my hands, I wanted to characterize its performance so I could proceed from a position of knowledge. The distortion and noise from this device turn out to be entirely acceptable for my needs. It has a delay setting which I'm sure will also help - but as a matter of course, I wanted to see what the native delay of the processor is. I set up my Scarlett 2i2 to measure both a loopback path and the DSP8024 using loopback as timing reference, and compared impulse responses. The mdat file is attached.
I see an approximately 1.7 ms difference between the two measurements. My (probably naive) questions: (1) where is the common 30+ ms delay coming from? Is that the delay from output through REW and then back into the measurement portion of the software? I had assumed that the use of a timing reference would account for that delay, but either it doesn't, or I'm not using it right. (2) is it correct that the difference between these measurements is the actual DSP8024 propagation delay?
I must have used this measurement screen 200 times and I never realized that was a base offset added to the measurement because I never used it. Sure enough, it was set to something ridiculous like 35 ms. That probably explains some of the puzzling things I saw with my sub timing measurements. I need to re-run my speaker test after moving them a few inches anyway - time to do it right!
