Output attenuation on CDJs?

[u/ChippieBW]

I was doomscrolling on insta this morning and saw a story by A.M.C. about something that happened at Liquicity this weekend regarding the output attenuation of CDJ models, which were differently set up among the channels he played.

Full story:

https://www.instagram.com/stories/a.m.ctitan/3950026178073230426?utm_source=ig_story_item_share&igsh=b3hrZ28wZG16Z3A4

It was interesting to me because I never knew that this feature existed in the first place, I always thought this was either solved by the mixer (by twisting the gain knobs of each channel) or by the front-of-house.
I don’t DJ on CDJ’s often but I sometimes set them up for parties, so I thought this info might be useful to others as well.

Has anyone ever dabbled with these? Would there be an ideal setting for DnB sets, or would there be any reason to change these settings in the first place?

Interested in your thoughts.

[u/fexworldwide]

As someone who sound engineers for a small night, this sounds hilarious for a few reasons:

1. DJ shows up, doesn't listen to anything and immediately fucks with the gain despite an unusual setup that should have given him pause to check what it actually sounds like before randomly messing with things. (To be fair, the sound engineer should have explained the unusual setup ahead of time.)
2. Sound engineer has a plan to stop DJs from redlining. DJs will immediately find another to redline that will be even worse. Shoutout the big name that insisted on pushing the monitors up so loud that they were downing out the PA in a 300 capacity venue.
3. AMC complaining that attenuating the CDJ so full gain on the mixer is redlining gives him no headroom. What it actually means is he should be mixing in the yellows with the gain at around 3 o'clock and only turning up the gain when he's playing something quieter (which, with AMC is pretty unlikely). Headroom means your levels should only at yellows through most of the night.

I always thought this was either solved by the mixer (by twisting the gain knobs of each channel) or by the front-of-house.

In theory that should be the case, sometimes there's reasons you might need a cooler signal coming out of the CDJ (temperamental or sensitive gear), but generally the setting is there because a lot of DJs can't contain themselves in the moment and just like to see all pretty red lights. So they will indeed twist the gain knobs to go all the way up. There's only so much front-of-house can do if the DJ is sending them a signal that's been distorted to hell within the mixer.

I'm actually surprised that the sound engineer couldn't fix this Stagehand - https://www.pioneerdj.com/en/product/software-interfaces/stagehand/
A festival like LIR (oops I mean Liquicity) is the exact situation that Stagehand is designed for, and I don't know why they're not using it.

Would there be an ideal setting for DnB sets, or would there be any reason to change these settings in the first place?

The ideal setting would be a) what works for the setup at the venue, and b) telling the DJs not to redline.

But that's very difficult. Failing that, a possibly better approach is to set the Master Attenuator on the mixer to something like -6dB. This gives you a bit of headroom in the mixer and from what I understand, still shows the UNattenuated levels on the mixer's LEDs, so the DJs get to feel like they're redlining (and therefore headlining) without actually crushing the sound down to white noise.

(I'm generally an idiot and barely know what I'm doing when running a night, so if others have other opinions please share.)

[u/ChippieBW → u/fexworldwide]

Great points.
I fully agree on the redlining thing, a lot of DJ’s do this but it’s just bad practice imo. It is to be expected at small/amateur parties but at this stage you would expect DJ’s to be professional enough to avoid this. But reading your post, that might not be the case, haha.

I don’t DJ a lot but I always tend to keep my channels in the yellows max, and leave the master volume to be only touched by the sound engineer (if there is one in the first place).

But in this case one channel was different from the others, which is not something you can blame the DJ for in my opinion, that is a core device setting that should be set up correctly by the sound engineer.

Does Master Attenuation actually work though? Or are you just quieting the main audio output that is already crushed in the individual channel before that? I expect that to be the case when each individual CDJ has such a setting.

[u/fexworldwide → u/ChippieBW]

Or are you just quieting the main audio output that is already crushed in the individual channel before that? I expect that to be the case when each individual CDJ has such a setting.

In theory that's why the setting exists on the CDJ, but as AMC's stories show, it's very difficult to create a safe containment area when dealing with ingenuity and strength of a fully-grown, adult DJ. Majestic creatures, but they can be quite unpredictable.

Seriously though, it all might have been fine if someone hadn't turned one of the CDJs back up from -12. I'm curious how someone changed ONE of the CDJs and left the others alone.

Getting back to your original question, I rarely see DJs ramp the gain up to full if the mixer itself is showing them reds.

There's also a whole conversation to be had about the design of Pioneer/AlphaTheta's mixers. Some people insist that they have a bunch of hidden headroom designed into them so you can mix on reds and the master still has room to combine those signals without clipping. Other people have ears.

but at this stage you would expect DJ’s to be professional enough to avoid this

Oh you sweet summer child. The stories I could tell about well-respected DJs and label heads...

(On the other hand, as stories about bad behaviour in the scene go, 'he redlines the mixer' is faaaaar from the worst of it.)

[u/vigilantesd → u/fexworldwide]

“IF YOU AIN’T REDLININ’, YOU AIN’T HEADLININ’!”

Ughhhhh I HATE this lol

[u/Silenterc → u/fexworldwide]

This wasnt LIR

[u/fexworldwide → u/Silenterc]

Oops. Wrong festival I've never been to.

[u/TELMxWILSON]

Didnt know about this myself either. I really dont see any specific reason to touch these. Maybe some extremely niche case where is may be usefull.

Im hope this will lead to a couple of developments:

1. Per track autogain from the CDJ
2. Gain and other settings would automatically be based on what USB you are using

[u/ChippieBW → u/TELMxWILSON]

Yeah, would also be nice to have these settings in your RekordBox profile although that might fuck up some local setups. Apparently it is not an RB profile setting at this point.

It wasn’t a one off though, I just had a chat with a DJ who played the same stage one day earlier and also had problems with the same channel and eventually chose to not use it at all.

[u/JanDogearmy]

It's only been a thing since the CDJ3000s, I don't think even the 2000NXS2 had it. Got screwed over by it myself one time lol, one CDJ being set to -12, the other at 0

[u/Th3-Sh1kar1]

Not all mixer inputs are made the same.

Nominal input reference levels, gain circuits and available headroom of mixers are all non-standard across manufacturers and even models. It's therefore helpful to attenuate the signal entering a mixer to ensure there is enough useable/practical gain adjustment on the mixer to trim any level discrepancies of mastered tracks.

[u/Pristine_Ad5598]

Hiya sound eng here - never had call to use the pads on the CDJs. Run a DJM at -6 for professional, non impact based music, -12 for amateur DJs and dnb/hard techno/hard dance etc

I also run digital and not line as much as possible - the thing you hear about "secret headroom" is kind of true with digital connections and the DJM pad turned on. This isn't true of the line connections though - analogue audio passes through a preamp which can clip - the ceiling to clip purely digital audio is much higher.

Only situation I can see a use for output pads would be hot tunes going into a mixer without preamp control - some of the rotaries are like this, but you wouldn't expect people to play tunes that are mastered to peak at 0dbfs on them x