Gain Staging

From Bose Portable PA Encyclopedia
Revision as of 01:04, 22 August 2006 by ST (talk | contribs)
Jump to: navigation, search

Gain Staging

Video Tutorial

Gain setup for a microphone picture of get plugged in page See the video on the main Bose site. Get Plugged In

Ken-at-Bose

Ken-at-Bose [1] talks about setting the gain for your microphone.

Please review the instructions for setting the trim level on Channel 1 and 2. Sing as loud as you're going to sing with your lips touching the windscreen and adjust the trim so that the LED just flickers RED. (You can do this with the channel and master volumes on the remote turned all the way down.

Remember that when you want to be your loudest vocally, you're lips should be touching the windscreen. You can always "work" the mic by backing away from it to lower volume but always remember that when you need to be loudest, you're kissing that windscreen.

This technique is true for ANY live amplification system, not just ours.

Bose FAQs

There are three gain settings for the primary channels (1 and 2) and two gain settings for the secondary channels (3 and 4).

Channels 1 or 2

To set the gain for the primary channels (1 or 2):

  1. Adjust the input gain. Set the trim for the individual channel at the back panel of the PS1 Power Stand. Supply a maximum source signal and watch the LED, when you start to see it flash red, back off slowly on the trim potentiometer until it flashes green again.
  2. Adjust the channel gain. The channel gain is controlled via the R1 Remote Control. With the master at zero, set the respective channel gain at 12 o'clock or 6 on the R1 Remote Control. At this point, the LED on the remote will be at the same intensity as the LED on the back panel of the PS1 Power Stand. This is considered optimum gain. The musician can then add a bit more from the R1 Remote Control if he/she requires.
  3. Lastly, the R1 Remote Control MASTER knob is the last stage of gain. This knob gives you control over all 4 channels of the PS1 Power Stand.

Channels 3 or 4

To set the gain for the secondary channels (3 or 4):

  1. Adjust the input gain of the individual channel. These channels do not have indicator LEDs but are optimized for 0dB line level signals, such as from an effects device, mixer or CD player.
  2. As above, the R1 Remote Control MASTER knob is the last stage of gain. This knob gives you control over all 4 channels of the PS1 Power Stand.

Owners Talk about Gain Staging =

Owner gittar-jonz [2] Dialing in your sound IS a personal preference, but proper gain staging does have some technical right and wrongs.

The accepted rule is to set your gain as HIGH as possible, as EARLY in the signal chain as possible - and adjust each consecutive gain stage until you reach the last component. This will give you maximum headroom and the best signal-to-noise ratio. Every signal carries some noise with it, and if you set your gains too low at the front (preamp/mixer/processor), and then try to compensate for it at the end (PAS), you will be magnifying the "noise" as well as the signal. The "cheaper" the equipment is that you're using in front, the more obvious this will be.

The easiest way to do this is to just VISUALIZE how your signal runs. Whatever your signal from the guitar or mic hits first - be it internal or external preamp, processor, mixer, whatever - maximize THAT trim control first. Having LED's to visually see the clipping makes this job much easier - just sing or play as loud as you plan to (turn the master down - you don't need to actually make noise to set your trims if you have LED's) and crank the trim/gain until it flashes red into clipping - then back it off a bit to give yourself some room. Then continue down the path of the signal chain - this includes any "inserts" into the chain - adjusting each component until you finally hit the PAS, which is the end of your chain.

Every piece of equipment that I've used in my PAS has benefited from this rule. I've had some pieces that had intolerable amounts of noise (the Digitech Vocal 300 comes to mind) when the gain at the Digitech was set low, and the PAS set high. When I reversed them back to the "rule" - set the Digitech gain as high as possible, and just adjust the trim at the PAS only as needed, it became a usable piece of equipment.


General Principles