[nick72]

Hi everyone!

First let me say that the new REW 4.10 is really quite amazing....Thank you John!!!

The RTA/Spectrum tab is very, very cool.
I have to admit though that I'm a big novice at this stuff so I was wondering a few things as I was trying the new Spectrum Tab features..

- What is the difference between RTA and Spectrum Analysis? In a sense, the graphs are similar yet different. I guess more to the point is, what uses would RTA have over spectrum analysis and vise versa?

- I noticed that when using the DB Y axis, my RTA and spectrum graphs are 20+ DB below the 75db reference when sending noise from the Generator, even though the SPL Meter reads 75 DB. Is this normal? When I take a standard measurement, it is graphed correctly. Here's a snapshot below with the two on the same graph.
The caption of the RTA reads:
"65536-point 1/48 octave RTA using Blackman-Harris 7 window and exponential averaging
Input RMS 94.3dB"

Thats all for now I guess. I'm sure I'll have more questions as I play with it a little more...

Thanks again for a really cool new version of REW!!!

 

[nick72]

Instead of using a soundcard calibration file, you can use a loopback cable on the left channel and use that as the soundcard calibration.

One of the things this new reference allows is speaker distance readout (called System Delay feature).
brucek

Thank you very much for the info.

Just to clarify, I would assume that means that I'd need to get splitters to split both Line In and Line Out 1/8" plugs of my SB Audigy 2ZS into the Left and Right components to do this right?

I've played quite a bit with RTA in REW this weekend. Somehow, as a result, I now have a ECM8000 and a XENYX802 on order. The RS meter doesn't seem to do RTA justice. I wasn't a huge audioholic, but it seems I've been pulled to dark side. :bigsmile:

Take care...

 

[nick72]

I don't really understand. To run REW you always required splitters at the line-in and line-out plugs on the soundcard, so as to break out the left and right channels. One of those channels was always left unused in the past.
brucek

Yes, I realised this shortly after I posted this. I now have the loopback set up and the system delay feature is now working... Thanks again...