Good weekend and Lake question

T

Terry Fryar

Freshman
Mar 31, 2011
9
0
1
Benton, IL USA
Had a good time this week at a regional festival...even with rain and storms early in the week. Got to provide stage/roof/audio/lighting/video for Saving Abel, Cavo, Easton Corbin, Thompson Square, The Band Perry and more to nightly crowds of 7K or so. Due to the local "sound police" we only hung 20 over 28 with some front fill, but it seemed to be enough (120dbC at 140'). Thanks to all the touring BE's, who were very good to work with and quite professional! I am so amazed at the skills these pros bring in every night...well done guys!! Also, thank you for allowing me to pepper you with questions...I love to learn why you do some of the things you do!

Now to the lake question. Have a 4x8 dolby lake dsp that drives a 4 way system. Got FIR set up for the tops, and IIR for the subs. Each set of LR modules are in a group (one for tops, one for subs). Controlling it with wifi and I have fairly recent software on the DSP and the laptop. Every now and then the wifi has trouble and the lake software on the DSP gets "out of sync" with the laptop. Normally, this isn't a big deal...but on occasion the lake will stop processing one side of my stereo sub feeds....argh! These feeds go into another DSP for arc delay/steering processing so it's not a big deal to temporarily strap all the outputs to one side or another of the lake...but the only way to get the missing output back is to reload the lake from a file from scratch.

I've tried restoring from a preset, forcing a resync, and removing a module and setting it back up...no dice...I see the input signal come in, but none comes out, and the output meter is blank. Nothing in the config has changed that I can see? If I do a "restore system as new" and use a file I'm usually back in business but it can take 45 seconds of no audio to do this. Has anyone seen this before? I realize the network needs to stay solid...but I'm surprised just allowing the software to run on the laptop to display the output meters can cause the DSP to stop processing audio if the software gets out of sync...geez...scary stuff!!

PS: Hey Bennett....we were using those FIR filters I asked about this winter on psw...we finally finished them and they seem to be working pretty well. None of the national BE's made any major changes and said the rig sounded just fine. I'm happy with that...especially considering how old those boxes are!
 
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Re: Good weekend and Lake question

Ahh...it's the old 2 or 3 space lake...with the 4 channel cards...what is that called? LP4D8 or something like that? It's got 1 4 ch input card and 2 4 channel output cards. It's not the new LM26....it's the pre-labgruppen one....with the big boat windows...;-)

Sorry...I guess the contour was the clair i/o one? I'm not up on my lake history very much!
 
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Re: Good weekend and Lake question

That's an interesting issue! Whenever I've had a Lake go out of sync, it just asks if I want to sync the data on the processor, or the data on the computer. Doesn't kill audio, and it only takes a few seconds. However, I would suggest a quality, high speed router for the Lake control. I've got an Apple Airport, and I've never lost the connection.

On the tablet side of things, are you getting a red bar under the input or output on your groups when it goes out of sync? Have you looked in all the modules and made sure nothing is muting when it goes out of sync?


Evan
 
Re: Good weekend and Lake question

Yeh Evan...it's a wierd one. There is no muting at all, and the settings are all there as if nothing happened! I even removed the module and recreated it to no avail! I can even watch the sub input channel getting signal, and the output meter right next to it has no signal....straaange! I know after trying either a preset recall or some other type of change, it eventually pops the red box up that says "out of sync". I think it might be a firmware bug, as I've never had any of the other channels go away...only the R sub output. Also, it takes several minutes of network problems before this happens. I can have a few network glitches and the lake is still ok. Plus, since I've got a mix of FIR and IIR, it's a bit of wierd configuration for a lake, but it works just fine. I had to switch out of FIR for the subs since it's such low frequencies...I don't have enough CPU (or time!) left in the DSP to do 4 way stereo FIR. The sub section ended up using IIR Linkwitz filters...which is fine. Given their placement, I have to phase align em anyway, so it's not a big deal...

I've got 5 wireless bridges that I use that are similar to the famous WRT54 routers, but with stronger radios. I use OpenWRT linux on em and they do quite well, but at this show I had about 3 folks stepping on my channel. After I changed to a clear channel, all was well! That's what I get being lazy on sniffing the area before I set up! ;-) I think if I just make sure the network is clear...I"ll be good on the lake. Heck, we could even hardwire I guess. I just wanted to see if anyone had run across this before? I always end up with the strange stuff!
 
Re: Good weekend and Lake question

wireless lake is fine for set-up, but it can get a bit flakey come showtime. I suggest you run hardwired ethernet to FOH, leave a laptop there, and control it with another laptop or ipad (running VNC)

This is a good read (even though it is meant for the new lab stuff, most of what they say applies).
http://labgruppen.com/media/downloa...etwork_Configuration_Guide_NCG-PLM_rev106.pdf
 

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Re: Good weekend and Lake question

Good document Rick! A good portion of this is directed at having audio over ethernet, but there is some good info there regardless! I'll be keeping this one!

Did a show this weekend and had no inteference...no trouble with the lake at all. I guess I really do need to consider a hardwire at FOH for the monitoring aspect at least. I'll keep the wireless so I can tune using my tablet, but perhaps I'll switch to hardwire during the show.

Thanks everyone!
 
Re: Good weekend and Lake question

Terry,

I've never had anything about the network take down a lake processor of any generation. Are you running the latest firmware, etc? The only time a Lake processor will drop audio in my experience is when reloading a whole new show file, so if you get out of sync and tell it to get the data from your computer that may be the problem. In general I assume the Lake has the correct settings.
 
Re: Good weekend and Lake question

Yeh, that's why I'm a little freaked...never seen a network side issue affect the DSP either! I'd have to check, but the PC software is pretty new...firmware shouldn't be too old as I recall. I've been using BSS/DBX/Xilica stuff for a while and I've never seen control software issues actually affect the DSP like this before.

I am in designer mode most of the time at a show....and the R sub output (ch 8 I think) is the one that's always affected. Either on the DSP meters on the unit, or on the software, you can see the input meter bar has signal....but the output bar is blank. Only way to recover is "load system as new". I tried preset recalls, forcing sync and some other things. In one case I ended up with the sub outputs always backwards from the others. One time, the "out of sync" shows up on the sub outs. The next sync...the sub outs are fine, but others now show "out of sync", so I know the DSP is getting off from the software!

Odd stuff indeed! I really think this is a rare firmware bug that's showing up due to my weird 3 way FIR stereo + IIR sub filters. Oh well, as long as my network connection is solid, I think I'll be fine!
 
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