Mackie Big Knob Studio Issues

[MJKlein]

I probably should set up a product review section of the site.... But I have to say:

These Adam T8Vs are the best damn recording monitors I've ever heard! Warm, not harsh and the UART transducers are the softest high end I've ever experienced. Their claim of less ear fatigue is certainly true. They sound warm and transparent.

But the Mackie Big Knob Studio is a big disappointment. The flexibility of the thing is great, but the functionality is very bad. I've spend about 5 hours with it and I'm considering sending it back already. I cannot work with a piece of gear that changes the stereo field.

[MJKlein]

I just got one of these yesterday and I've had about 5 hours with it. Today I did some tests and discovered that it apparently has audio on a ganged pot instead of using a VCA. My stereo field changes depending upon where I put the knob. This is very bad and to make matters worse, the USB connection is not consentient with the analog inputs.

I'm not really in the business of making YouTube videos but I think that this situation calls for one to be made to show my test platform with Reaper and the X32. At the end of the day I really think that I have to send the controller back. But I have no idea if a replacement of the same type would have the same issue. I tend to think it would.

The new Behringer monitor controller/interface uses a VCA to control the volume.

[pmaillot]

Sorry to hear that (for the controller), but not surprised you love the Adam monitors!

The stereo field should definitely not be changed (unless specifically asking for that to happen, of course). Anything in the doc that would imply the change of st field? Would/could it be linked to some kind of phase issue?

-Patrick

[pvannatto]

The new Behringer monitor controller/interface uses a VCA to control the volume.

That is one of the advantages of cloning something. You can always make it better.
The problem will be trying to get one - before you and I are in retirement homes...

[MJKlein]

The new Behringer monitor controller/interface uses a VCA to control the volume.

That is one of the advantages of cloning something. You can always make it better.
The problem will be trying to get one - before you and I are in retirement homes...

I may bring the thing down to my friend Dennis and see if he can come up with a mod for it.

[MJKlein]

Sorry to hear that (for the controller), but not surprised you love the Adam monitors!

The stereo field should definitely not be changed (unless specifically asking for that to happen, of course). Anything in the doc that would imply the change of st field? Would/could it be linked to some kind of phase issue?

-Patrick

What put me on to this was listening to my old mixes + commercial songs and wondering why they were so right-heavy. I had 2 new pieces of gear going at the same time, which is always a troubleshooting nightmare. I started with the Adam T8Vs level knobs straight up (there is no detent anywhere in the range!). I kept bring up the level on the left monitor to match and as soon as I moved the big master volume knob the stereo spread changed again. Believing that the Adam's are consistent (to put it a better way - I trusted Adam Audio more than Mackie) I carefully put the monitors all the way up just so both level controls would be at the stop and presumably equal. Sure enough, the stereo spread was there.

Nothing about that in the docs. If it's a phase issue that would be even worse! I did see one YouTube video where a user claimed that the trim pot "colored" the sound but did not elaborate.

The Test

I made a test bed in Reaper. I recorded 2 tracks each of 100 Hz, 1kHz, and white noise. Each pair of tracks was recorded at the same level and from the same bus using the X32 internal oscillator. The tracks are identical. They are not copy/paste. They were recorded at the same time in real time.

Bringing up a pair of test tracks on the X32 and panning them hard L/R with the channels unlinked allows me to adjust one of the faders until the audio disappears when the Mono button is pressed. In each case, I used the channel setup screen and adjusted the fader levels exactly to 0.00dB, and in each case, the test signals go away instantly when pressing the Mono button. The X32 seems very consistent and well designed! This confirms the test signals are good in Reaper and at least up to the outputs of the X32 control room jacks, everything is as it should be. (1)

When pressing the Mono button on the Mackie Big Knob Studio, the same thing should happen. The Mono buttons on both devices are working with the same signal. Pressing the Mono button on the MBKS lowers the overall level but there is always something being heard. That is the delta between channels. Unfortunately turning the big master volume knob varies the signal by quite a bit. There are even some spots where it jumps as if there were dead spots in the potentiometers.

Going back to the X32, using an encoder to precisely move one fader (I arbitrarily chose the right fader of each pair) and watching the fader level display, I have to move the right fader to approximately -.9 dB to null the test signal. Then, moving the big knob until the signal is the loudest, the fader has to go to -1.7 dB to null the signal. This confirms my feeling that the mixes were right-heavy.

The other bad part is that the input trim knob does the same thing! Apparently there are 2 ganged pots with audio on them that we have to deal with, not just 1 ganged pot. If I null the text signal and then move the input trim, the problem comes back. It also is erratic.

If the MBKS was consistent I could make adjustments for that by sending a control room signal that was attenuated on one side to match the input level imbalance (the trim pots have no individual channel adjustments). But that's not a solution since the issue is not consistent across the volume range.

The USB connection is all over the place. It has a separate input that is not adjustable and must be adjusted in the PC itself. I'm not going to bother since the master knob moves it around anyway.

I believe that my JBL M-Patch active is better than the Mackie. I wanted to replace it because it's old and I had to open it up and spray the pots because they are wearing out. I will probably go back to the M-Patch after I shoot the video.

(1) I did null the audio in the MBKS by moving one of the faders on the X32 as previously described, and then I moved the X32's Control Room level control to see what happened. Moving that control had no discernable effect on the null.

If anyone can find a flaw in my logic/method, I would appreciate knowing that before I make a fool of myself on YouTube yet again.

[pmaillot]

It looks like the pot is not good quality and the pair of pot tracks are not matching on top of being unreliable.
The mod you need is to change the gang pot gor a good quality one (Alps or something equivalent).

Annoying for a new piece of gear...

-P

[MJKlein]

It looks like the pot is not good quality and the pair of pot tracks are not matching on top of being unreliable.
The mod you need is to change the gang pot gor a good quality one (Alps or something equivalent).

Annoying for a new piece of gear...

-P

Yes. I was also thinking that it may be possible to add some components to balance the pots. I have to weigh the options of opening it up and messing about, or sending it back and getting either a new one or another type altogether. The hit is finding one with the USB option too. There are lots of very high quality monitors controllers with no USB capability.

[MJKlein]

My friend Dennis is recommending a stepped attenuator.

[pmaillot]

Stepper attenuator: best option in terms of pairing the two channel levels. Not the most versatile when it comes to fine adjustment. Cost is higher too.

Th behringer studio xl may be worth waiting for if you want standard and usb control in th same package. Send your faulty one back for refund and keep 250 euros on the side for the "soon to come" studio xl.