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Yamaha LS9 input gain

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Mac Kerr:
Corne Stapelberg wrote on Thu, 09 September 2010 02:30

I need to ask this again, and forgive me because there is a few posts similar to mine already.
I am using my Yamaha LS9 32 for about a year now.  Last night I did a gig, the main act was only a acoustic guitar and vocal (SM58 Shure mic)
Very very good international artist.

Long story short :  During his last song he played a bit louder than during the whole show and sound check and I got digital distortion on the quitar channel ( -6 dB) on the channel strip.

I know -18dB is the way to go.

My dumb questions are the following:
1 :)Are the channel strip level indicator the same as the level when you "QUE" your cahannels to check the input gain?
2 If you run into levels of say also -6dB FS on the outputs of the desk, will I also get digital disortion?
3 Is it normal for a LS9 to give digital clipping at -6dB iput on a channel


Is there some reason you feel you need to run the consoles levels that hot? Generally recommended levels are -18dBfs to -12dBfs as maximum levels. That is creating a level out of your console of +6dBu to +12dBu. On an analog console with analog VU meters they would be pegged in the red at that point. Turn down your input gain.


Bradford "BJ" James:
This bugs me. So you have to monitor the input level on the meter to hit -18 max (I usually go a bit hotter). I guess I'm missing something....why doesn't the clip indicator light when I approach or exceed this level. I can see setting the IL a bit less to leave room for peaks, but -18 is less than halfway up the meter on an LS9 or an 01V.
Not whining, just looking for an explanation I can understand. There must be a reson.

Tim McCulloch:
You're operating in the Digital Realm that eventually gets turned in Analog Love.

With a 16 bit converter, 0dBFS is 1111111111111111.  That number corresponds to the maximum Analog Love Level, which is +24dbu at the output of the console.  That number means THERE IS NO MORE LEVEL, Digital Realm or Analog Love.  Headroom?  Zip, zero, nada.

You wouldn't run an Analog Love console at that level even at peaks.  If you PFL an input and trim the gain so that the peak signal is 0db on the Analog Love Meter, you are still about 20dB UNDER the maximum output capability of the mixer.

The Digital Realm clip indicator on the input is usually the "Out of 1s" indicator.  The actual analog electronics in front of the A/D converter doesn't clip until you're past the point of "out of 1s."

The gain staging you're used to in Analog Love consoles is implemented differently in Digital Realm mixers, and since we're long past the days of 8 and 12 bit words it is not necessary to use every available bit in an effort to keep things above the digital noise floor.

For the OP, I too suspect the DI or other piece in the signal chain as you were still below digital or analog clipping.

Have fun, good luck.

Tim Mc

Corne Stapelberg:
Hallo Mac

I always run my board at -18 dBfs and try to peak at -18, maybe -12 dBfs at MAX scenario.  I just want to try and get the reason for this BAD SCENARIO.  Output on console was at -24 dBfs.


Corne Stapelberg:
Hallo BJ

The moment I heard the BAD SOUND, I instantly grab the channel input gain, and turned it down while I was also hitting the QUE button to monitor the input signal on the colprit channel (Acoustig Guitar through Behringer DI 100 DI).  The bad distortion was still there when I had the input gain level at -6 dBfs on the LS 9. -6 dBfs was the hottest the signal went at all.

This is why I am also asking the questio :
Is the led meter indication on each channel a true representation of the channel level that is the same than when you hit QUE and monitor the levels on the master output led meter.

I am also always using my laptop with Yamaha Studio Software running to monitor input levels



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