RTA overlayed on of the GEQ
For each of the GEQ's can you overlay a RTA on top of the GEQ display ? That way you can see which frequency band is causing feedback issues.
Here is an idea for an RTA feature that the DL team should be able to implement fairly easily (hopefully in V1.5):
On the DL, add just a single FFT block to the DSP code that is always fed by the solo, maybe with a variable time window. Most DSP vendors already have canned FFT code blocks already available so most of the work would be on the iPad interface. Any time a solo is active, stream the FFT block output back to the iPad (which should not take much bandwidth since only output display info gets sent)
On the iPad, when you hit the solo button for any channel or output, a 3x5 inch FFT display pops up over the slider area, showing the FFT output of the solo'ed channel or output. Touch any area outside the FFT display and the FFT window disappears. Touch any other solo button and that channel/output comes up in the FFT window. Touch inside the FFT window area and it pops to full screen, with the FFT on one half and the channel or output EQ (preferably parametric) on the other.
Then, during a live show, if you start to hear a ring, you can quickly solo each of the most likely suspect channels, find the culprit and pull down the offending freq before it got too bad - its the same concept as running the solo out to a rack RTA, except an FFT would make it a lot easier to see a persistent ring even if its volume is relatively low. You could also solo the monitor aux and decide whether to pull the freq out of the monitor or the input channel.
For ringing each monitor before the show, just bring the gain up until it starts to ring and then solo back and forth between the monitor and channel inputs and use the EQs to tamp down the ringers. Same as what you do now, except now you have a nice visual of the rings and which inputs are causing them
For EQ'ing the room, the LR output gets a solo button (which admitedly seems non-intuitive, but it allows you to pull up the FFT and EQ window for the mains in a way that is consistent with everything else - there may be a better way to do this from user interface perspective). The DL would have an internal pink noise generator that is controlled by a button in the full screen FFT view. When the pink noise is on, the LR bus can be solo'ed (to send the output to the FFT display) but only the pink noise goes to the LR outputs. That way you can plug a reference mic into one of the inputs without creating a feedback loop. Since the iPad mics dont have good low frequency response, I dont really see an alternative to walking around with a reference mic - but since you also have the iPad, you can now walk around and have a much better idea of where the low frequency nodes and swells are, and now the EQ is already in your hands if you want to change something.
Obviously there are a lot more bells and whistles that could be added, but something like this would be very useful, should be fairly straightforward to implement and shouldnt tax either the DL's DSP or the iPad interface very much
Built in RTA, FFT or spectrograph would be great, as would an indicator on the output EQ as to which band is running hottest.
In the short term, if Master Fader would keep its synch in the background, that would make it a lot easier to swipe between MF and a 3rd party RTA - or for that matter, music player, talk back mic app, etc.
Right now, it takes about 3 seconds for MF to synch when you swipe to it - which sounds fairly fast, but if you want to make an adjustment, it seems like forever.
Aurélien Claranbaux commented
This could use the built-in Mic of the iPad !
Jeremy Taylor commented
It should be an FFT spectrum, not merely an RTA. RTA is sufficient for G-EQ but more detail needed on parametric EQ
Charlie Smith commented
I also use a DEQ2496 for RTA. It shouldn't be that hard to output pink noise from the iPad and use one of the channels as an input for a reference mic, and then auto-EQ the 31 band graphic.
Brian, The Soundman commented
I Love my DL1608....... But line 6 already has what everybody is asking for, And All suggestions,
Giovanni Stefani commented
I really like this idea. As it stands now, I have to send the mains down to my Behringer DEQ2496 and run the GEQ flat out of the DL1608. The ears should be the final, but the eyes get you in the ballpark.
This would be an awesome feature!
I would choose a spectragraph over an RTA anyday.
just to chase a build up or find an errant squeel.
but I say train your ears, not your eyes. I can usually hear what needs to be done
Phil Gutowski commented
This would be a fantastic feature, however I am curious if the processor power is there. There are other RTA apps that work well, but it would be more accurate to analyze only the output you are working with, and not just use a house measuring mic.
Mike Mullin commented
Larz Hanson commented
If this can be done with the existing processing power, it would be an AWESOME feature! Additionally, it would be great to see a Post-EQ, pre-fader "RTA" curve overlaid on the Channel View EQ page to give an even better visual of what the channels are doing.
While the SMAART system integrated into the PreSonus VSL software looks like it might work nicely, it also has a bothersome look like those strange pictures you need to stare at a minute to see the actual image. If Mackie chooses to integrate an RTA curve with the channels and GEQ's, I hope they use a method that goes along with their clean, sharp layout.