Topic: R1 metering and peak detection

[pgoelz]

Hi gang,

After reading discussion here about the R1 and its ability or lack thereof to correctly meter incoming audio in record, I decided to do some simple testing. 

I created a file that contains a 1KHz sine wave at various levels and with various peak levels.  One portion contains a 1KHz sine at -10DB with 3 cycle peaks (ie., 3mS duration) to -1DB.  Another portion contains a 1KHs sine at -15DB with 3 cycle peaks to 0DB.  A third portion contains a 1KHz sine at -15DB with 1 cycle peaks (ie., 1mS duration) to 0DB.  I then played this file into the R1 line input. 

What I found was that in all cases, the R1 displayed each peak correctly, although slightly delayed.  In other words, it never missed a peak and each peak was displayed at the correct level. 

I then looked at the level per meter segment.  With 15 segments, I had suspected that the meter was in fact a bitscope..... displaying one segment per bit.  So I created a couple files with a 1KHz sine and stepped levels.  What I found was that the R1's meter is actually a simple linear scale with 3DB per segment.  Since there are 15 segments, that means the meter begins at -45DB and ends at 0DB.

I hope this puts to rest some of the concerns we have all had about the apparently crude R1 metering.  Too bad Edirol couldn't just come out and tell us what the silly thing does!  But now you know.   

Paul

[pgoelz]

edirol actually does have some metering information posted on their website in the faq area...(see below) matches what you found in your testing

my complaints with the metering on the R-1 are more around what you found
--its slow
--its not discrete (left and right are combined into 1 meter)

Yeah, someone on the Edirolr1 mail list reminded me that Edirol had published meter scale info before. 

As for the slow metering, I don't really care.  It is fast enough to tell me what I need to know.... and especially given the fact that it does not seem to miss transients regardless of the update speed.  Since there is no way to correct left/right balance issues with the internal mics, the single meter also doesn't bother me.  However, I can see it being a real problem if you are using an external pre. 

Paul