Mackie CFX16 mixer issue

[Aerovette]

This is a mixer used by my band for years and we never really utilized it for a stereo configuration as part of the PA. Now I want to record backing tracks with vocals removed and I can't seem to get the desired results. Here is what I have done and perhaps someone can tell me how to stop chasing my tail.

I have a laptop as the source for the backing tracks and they are confirmed to be stereo using a youtube channel test.
I have a QSC amp to provide playback and as a monitor since I am not yet concerning myself with isolation or multi-tracking (baby steps).
Initially, I was splitting the stereo signal from the laptop in to two channels on the mixer and panning one channel left and the other channel right. I assigned left to the 1-2 subset and the right to the 3-4 subset sliders.
The amp is not set up as bridged. It is set for stereo. In this configuration, I was getting mono out. That is one problem to address.

I abandoned that set up and went to channels 15 or 16 which have a designated left and right. Same problem, no stereo out, only mono. It did not matter which way I panned, I got the same sound.

My next step this evening will be the Tape In left and right and see what that gives me.

In the ch 15 or 16 configuration. I pulled a main out cable from the mixer and got nothing through the remaining main out. I went to the amp and turning the left dial had no impact. Everything is coming FROM the right but somehow still being amplified in mono across both left and right through one channel of the amp.

I plugged headphones into the headphone jack and ran the test and it is still giving me left and right in both speakers.

What gives? What am I doing wrong? Could the mixer have an issue?

Thanks in advance.

 

[ecc83]

So essentially you are trying to reproduce a stereo signal from a laptop's 1/8" jack via a mixer and getting double mono?

Is the mono one channel "twice" or an actual mono mix? If you are not sure you could make a twin tone L/R track in Audacity, 440Hz and 1kHz say.

Do the meters on the Mackie show a stereo signal or just track locked? If so the 1/8th to 1/4" jack lead could have a short in the L/R pins (hate 'em!) This is easily proved with a $20 digital meter which, IMHO every muso/recordist should have and certainly any band!

In fact you probably should get an Audio Interface PDQ. This will run the tracks out of the laptop via USB and be far better quality. A basic AI such as the M-Audio M-track will serve but if you CAN crack £100 the Steinberg UR22 is better. Better still and would compliment the mixer is the Native Instruments KA6.
Lastly for now. Audacity is very good and useful but limited for recording and track building (and no MIDI) Do look at Reaper.

Dave.

 

[Bubba po]

Hi, Aerovette.

First of all you need to make sure that the lead you are using is actually splitting the tip and ring signals of the TRS mini jack (headphone jack) into separate signals, not just summing to mono and splitting that signal to two jacks. Use a continuity tester to check that the tip of the headphone jack goes exclusively to the tip of one jack and the ring of the headphone jack goes exclusively to the tip of the other jack.

Use two channels (i.e. channel 1 and 2). Plug the left hand stereo signal into channel one and the right hand one into channel two. Set the input gain.

Use the Channel Assign buttons to assign channel 1 to Subgroup 1/2 and pan it hard left. Assign channel 2 to Subgroup 1/2 and pan the channel hard right. Raise the faders to 0dB gain.

Go to subgroup 1 and engage the Assign Left button. Go to subgroup 2 and engage the Assign Right button. Raise the subgroup faders to 0dB gain.

Raise the master fader to the required listening level. The music should be in stereo.