Topic: Soundboard feed clipped before recorder?

[achalsey]

Not sure where to put this, so I'll try here.

Haven't had this happen before, so slightly confused.  Is it possible the SBD feed was clipped coming out of the board before it reached my recorder?  Running a tascam 680.  I had levels peaking at about -12 db, not even close to 0 db, so assumed I was fine, but when I loaded it into Audacity I got the picture below.  Haven't done anything to it yet, thats just what showed up.

It was an extremely loud show.  I was actually on the phone outside for a good deal of the set, but when I was in I didn't seem to notice any clipping from the PA, however I did have ear plugs in and also wasn't totally focused so may have missed it.

Is this something people have experienced before?

[yousef]

Could this not be classic brickwalling? Overloading the analogue input of the recorder and distorting there.

Also, I'm not sure if this is relevant but we just recorded a show where all our levels were fine but the lead vocal clipped track repeatedly - a really nasty digital-sounding distortion, despite never hitting anything near 0dB on our recorder.

Listening to the ambient tapes revealed that it was present coming out of the PA like that but ears are clearly more forgiving in the live environment.

[Sebastian]

The 680 has line inputs with a nominal level of +4dBu, so that should have been sufficient to handle a pro-level signal from the SBD. Therefore, I'm guessing the signal was distorted before it reached your recorder.

This happened to me in the past. Especially for very loud rock music in small venues it's possible for the stage sound to overpower the distorted PA so that the PA distortion is not really audible in the room.

[RoganSarine]

Classic soundtechnician not setting up a proper gain structure. The brickwalling is actually very common in smaller venues, simply because most sound technician's are inexperienced.

I always bring headphones and ask if I can fix their soundboard when this happens - as it happens to me so frequently. It's why I always use room microphones as my main source of sound. My soundboard feed just helps me pull out any instrument (usually vocals) that are missing.

[runonce]

It might help to know the how you took the feed from the board to the recorder?
And - How does the recording sound?

It really looks more like overloading the recorder input.

Are you certain you were configured for line (and not mic) input levels?

If the board feed was clipped somehow - I dont think the waveform could be so flat across the top without being noticeable in the room.

He said he didnt hear any distortion at the show - and it was loud.

[Church-Audio]

The 680 has line inputs with a nominal level of +4dBu, so that should have been sufficient to handle a pro-level signal from the SBD. Therefore, I'm guessing the signal was distorted before it reached your recorder.

This happened to me in the past. Especially for very loud rock music in small venues it's possible for the stage sound to overpower the distorted PA so that the PA distortion is not really audible in the room.

Actually most sound boards are capable out putting out much more then +4 more like +25 db at the output. Of course this does depend on the output that was being used. I would say you overloaded the output of the recorder. This is yet another reason why you must listen to the feed with a pair of headphones coming out of the deck to make sure its not overloaded. Its also best to make sure you are getting most of the gain from the recorder and not the soundboard. In this case because the signal to noise ratio is not as important for line level outputs. And most guys that are mixing are not paying attention to the output levels the assume your gear can handle anything they can throw at it. I would say take a level that is half of what you would normally want and then boost with recorder if you must. Headroom is always the issue. Most recorders have a buffer amp on the line input that is the culprit when it comes with overload. This is usually way before the line in attenuation so levels can look great but be overloaded big time. This topic has been well discussed in other threads.

[achalsey]

Thanks for the replies guys.

I'm not actually sure what outs the board was using.  They have a patch bay set up in a corner sort of away from the board.  I used RCA > 1/4th adapters.  I was definitely going line in though.

I'm still on the fence after reading through the responses on whether it was the recorder or board that was brickwalled.  Many of us get patches from this place (Grey Eagle, Asheville) pretty often and have never had any issues.  The sound guy is pretty good and I would assume knows what level he normally puts the feed at.  Also, the feed is mostly just drums and vocals, so when I zoom in on the wav file its actually just the drum hits that are clipped which makes me think it may have been through the PA but it was overwhelmed by everything else so not noticeable in the room.

[runonce]

Thanks for the replies guys.

I'm not actually sure what outs the board was using.  They have a patch bay set up in a corner sort of away from the board.  I used RCA > 1/4th adapters.  I was definitely going line in though.

I'm still on the fence after reading through the responses on whether it was the recorder or board that was brickwalled.  Many of us get patches from this place (Grey Eagle, Asheville) pretty often and have never had any issues.  The sound guy is pretty good and I would assume knows what level he normally puts the feed at.  Also, the feed is mostly just drums and vocals, so when I zoom in on the wav file its actually just the drum hits that are clipped which makes me think it may have been through the PA but it was overwhelmed by everything else so not noticeable in the room.

A lot of sound techs are more tolerant of red lights/peaks on the drum/percussion channels.

The peaks are so brief, they can be unnoticeable...but they might look a lot different to a recorder (compared to an amplifier.)

[SmokinJoe]

I can't see your picture at work, firewall blocked I guess.

Using RCA -> 1/4 adapters means you are running unbalanced in, and generally that takes about 6db out of the headroom.  I'm explaining it poorly, but the general idea is correct.  If you have the option of 1/4 TRS connections out of the board that is preferable.

I've had plenty of SBD feeds where the guy is overdoing the compression a bit and it starts to gets crunchy.  Coming through the PA it's so slight that it isn't noticeable, but in the clarity of headphones at home, you can hear it.

If you accidentally turned on the limiter on your 680, that would cause the situation you explained.  That becomes the overdone compressor.

[anodyne33]

Thanks for the replies guys.

I'm not actually sure what outs the board was using.  They have a patch bay set up in a corner sort of away from the board.  I used RCA > 1/4th adapters.  I was definitely going line in though.

I'm still on the fence after reading through the responses on whether it was the recorder or board that was brickwalled.  Many of us get patches from this place (Grey Eagle, Asheville) pretty often and have never had any issues.  The sound guy is pretty good and I would assume knows what level he normally puts the feed at.  Also, the feed is mostly just drums and vocals, so when I zoom in on the wav file its actually just the drum hits that are clipped which makes me think it may have been through the PA but it was overwhelmed by everything else so not noticeable in the room.

A lot of sound techs are more tolerant of red lights/peaks on the drum/percussion channels.

The peaks are so brief, they can be unnoticeable...but they might look a lot different to a recorder (compared to an amplifier.)

the red lights are there to let me know that channel is on