286A problems, hum, clipping
celtics23
Posts: 7
Hello,
I've had several years of experience using an EV RE20 paired with a 286a at an old audio facility where I've been doing voiceover. In building a new facility that is now coming together, I purchased several 286a's to pair with RE20's, since I always liked the results.
I'm having some issues with both hum and clipping that are not similar to anything I experience in the previous setup with the same equipment. The currently signal flow is RE20=>XLR cable=>286A=>1/4" to XLR cable=>ARC-8 Arrakis mixer input. I am monitoring the sound through the mixer's headphone out.
First and foremost, there is an audible hum in the headphones that seems a bit loud relative to the level of the voice. How might I explore eliminating this? With such simple cabling and connections, I'm not sure what can be done.
Secondly, even when setting the preamp to a good level, adjusting other settings, including compression on the mixer, can create clipping. I haven't experience this before...is it a suggestion that the preamp is too high? If i move it down, then the signal becomes almost too low to be audible when adjusting compression settings again.
Any suggestions would be appreciated, I have already gone through the 286a "setup guide" that dbx provides.
I've had several years of experience using an EV RE20 paired with a 286a at an old audio facility where I've been doing voiceover. In building a new facility that is now coming together, I purchased several 286a's to pair with RE20's, since I always liked the results.
I'm having some issues with both hum and clipping that are not similar to anything I experience in the previous setup with the same equipment. The currently signal flow is RE20=>XLR cable=>286A=>1/4" to XLR cable=>ARC-8 Arrakis mixer input. I am monitoring the sound through the mixer's headphone out.
First and foremost, there is an audible hum in the headphones that seems a bit loud relative to the level of the voice. How might I explore eliminating this? With such simple cabling and connections, I'm not sure what can be done.
Secondly, even when setting the preamp to a good level, adjusting other settings, including compression on the mixer, can create clipping. I haven't experience this before...is it a suggestion that the preamp is too high? If i move it down, then the signal becomes almost too low to be audible when adjusting compression settings again.
Any suggestions would be appreciated, I have already gone through the 286a "setup guide" that dbx provides.
0
Comments
With all processor settings set to off and output at 0db, the hissing is worse when process bypass is NOT pushed in/turned on.
Also, when going through the startup guide, even turning the preamp gain past +15 creates incredible clipping...in the past, i've had this setting somewhere between +30 and +40. I have no idea why the mic level is coming in so hot, but i see no way to reduce it to get a better "starting point" for the signal level.
I've confirmed the problem is not in the mixer itself as if i disconnect the microphone and 286a from the mixer, all warble and hissing goes away.
I suspect that we are dealing with an interface problem. The 286 (I have one) has an output that appears to be somewhere between a +4 balanced configuration and a -10 consumer level device. I always used a balanced 1/4" cable and used the line input on my mixer and had no problems. If you have a converted cable (balanced 1/4 to XLR) make sure that the tip of the 1/4" is routed to pin 2 of the XLR. Otherwise try a TRS > TRS 1/4" cable and insert it into a line input on the mixer.
Perhaps the J45 inputs would work? I realize that they are euroblock but that's not a problem is it?
I have to assume that the mixer you used before was NOT the same?
Gadget
Correct, the previous mixer wasn't the same. it's the ARC-8 now and before it was an old ward beck board, and i actually don't know the exact cabling sequence into the board. What you're saying makes sense...a couple of questions:
-How can i check the routing of pin 2 and ensure i have what i want (routing to pin 2 as you mentioned)? is there a guide online? this isn't something i've ever done before.
-Using the line input on the mixer solves the problem and everything works "perfectly." PRoblem is, the reason i GOT a mixer with the XLR inputs on channels 1 and 2 is to use those inputs for the mics, and since they only have XLR inputs on those channels, i will lose 2 channels altogether if i put all the mics on line inputs, something i can't do.
Using a simple ohm meter to confirm continuity will likely be the only way unless the connectors on the cable are capable of being opened and the color codes of the cable verified to specific pins.
Then you can try a simple line to XLR converter unit:
http://www.radioshack.com/product/index ... Id=2062444
or a direct box:
http://www.google.com/products/catalog? ... FoQ8gIwBg#
http://www.google.com/products/catalog? ... FcQ8gIwBQ#
To make the interface for you...Why did you pick THAT mixer? seems kind of limited in it's scope....( I'm an old FM radio engineer so I'll understand if you have a specific reason)
Gadget
It was a price issue, it was the only "broadcast style" console for around $800. Obviously a mistake...
I did read that the mic inputs on this mixer are preamped, meaning i am essentially using 2 preamps when using those channels. I am going to try turning the trim all the way down on those two channels and seeing what the result are.
G
New problem is this: Line level output on the dbx going to line level input on the mixer is only coming through in stereo. This is using a stereo breakout 3.5mm TRS to dual rca cable. Is there a different cable that will succesfully get stereo into the mixer?