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8020A volume control position for matching input sensitivity

resound, modified 7 Years ago.

8020A volume control position for matching input sensitivity

Youngling Posts: 2 Join Date: 8/15/14 Recent Posts
Dear community/Genelec team,

I recently set up my stereo pair of 8020A monitors again and wondered how to set the volume control matching the mixer output.
Though me not having a real professional setup and having discussed the volume knob thing a few times on this forum, would you be so kind and review my thoughts on the "correct" output levels?


[*:1dr9dweq] My Behringer XENYX 802 mixer delivers +4 dBu (or is it +6 dBu??) on "main mix" out when the uppermost green LEDs are on. OK, this one should actually be answered by Behringer.
[/*:m:1dr9dweq]
[*:1dr9dweq] General Genelec recommendation (from a few threads earlier on this forum) is to turn 8020 monitor volume to max. clockwise position (= -6 dBU input sensitivity leading to 100 dB SPL@1m). Right?
[/*:m:1dr9dweq]
[*:1dr9dweq] According to that FAQ http://www.genelec.com/faq/electrical/76-how-does-the-input-sensitivity-work-on-genelec-monitors/ the input sensitivity of the 8020A is calculated as:

[list:1dr9dweq]
[*:1dr9dweq] input sensitivity on max volume control position ==> -6 dBu ==> 100 dB SPL@1m[/*:m:1dr9dweq]
[*:1dr9dweq] max rms output SPL from 8020A datasheet ==> 96 dB SPL@1m[/*:m:1dr9dweq]
[*:1dr9dweq] additional rms input level required for max rms output ==> -4 dB[/*:m:1dr9dweq]
[*:1dr9dweq] max input level required for max rms output ==> -6 dBu + (-4 dB) = -10 dBu[/*:m:1dr9dweq]

[/*:m:1dr9dweq]
[*:1dr9dweq] So with the volume knob fully on I could drive my monitors to a healthy maximum power with only -10 dBu mixer output. Right?
[/*:m:1dr9dweq]
[*:1dr9dweq] If I wanted my mixer now to output its +4 dBu, does this mean the monitors' input sensitivity should then be set to -6 dBu + (+4 dBu - (-10 dBu)) = +8 dBu. Right?[/*:m:1dr9dweq][/list:u:1dr9dweq]
To what position (e.g. 12 o'clock instead of fully clockwise) should I turn the monitor volume control to get those +8 dBu sensitivity instead of -6 dBu? What would that position be if it turns out the mixer can even output +6 dBu instead of +4 dBu undistorted?

Thank you so much for your comments
Dominik
ilkka-rissanen, modified 7 Years ago.

Re: 8020A volume control position for matching input sensiti

Yoda Posts: 2564 Join Date: 3/23/09 Recent Posts
Hi Dominik,

Your calculations are correct but I would still recommend adjusting your speakers to maximum input sensitivity because it's difficult to set them to for example to +8 dBu without measurement devices. I am not very familiar with the Behringer device but doesn't it have adjustable output level? Can't you adjust the maximum output there? And where do you have the actual volume/gain control in the system?
resound, modified 7 Years ago.

Re: 8020A volume control position for matching input sensiti

Youngling Posts: 2 Join Date: 8/15/14 Recent Posts
Hi Ilkka,

thank you very much for your reply.

First I have to admit using the 8020A pair just for playback of music at my desk, for now I don't do any recording.
The Genelecs were simply the best choice for high quality audio from ordinary stereo sources like CD, USB audio interfaces etc.

I connected those sources to one of the smallest mixing devices available and am using it as a pure stereo line mixer.
The Behringers in this price range have no general output level control. There are some better models that allow an on/off switching between +4 dBu and -10 dBV level. My model has just a "main mix" fader plus channel faders. As they don't mention the exact output level in their manual, I assume it is always max. +4 dBu as long as you stay in the "green volume LED" area.
(By the way, the Behringer 802 is far from perfect, it makes a clearly audible "white" noise from 50% output level upwards.)

Thus, I can only control the overall volume at the "main mix" or at the 8020 volume knob. When I turn the 8020s to max. volume I have only a few millimeters (i.e. about 25%) on the mixer to go from silence to extremely loud at 110 cm listening distance.
Does everybody working in a studio do it like this?

I'm just curious what would be the setting on the 8020 that results in optimal sound quality.
If you say 100% volume on the 8020 combined with all other kinds of attenuation on the other devices would be optimal, I'm OK with that.

Greetings
Dominik
ilkka-rissanen, modified 7 Years ago.

Re: 8020A volume control position for matching input sensiti

Yoda Posts: 2564 Join Date: 3/23/09 Recent Posts
Dominik,

Actually it is not about optimal sound quality as long as you won't clip the signal. It is mostly matching the input sensitivity of the speaker to the signal level so that you have adequate range for volume control etc. Now you obviously have limited range which is not desirable. You should start to experiment with the speaker's gain knobs, turn them counter clockwise until you reach good working range for the volume control on the mixer. The actual input gain value doesn't really matter here. Make sure both gain knobs are in the same position for proper balance between the speakers.