I have a studio master EPM 12 mixer and a Yamaha PSR-S900 Keyboard in Church.. I am connecting the keyboard using a TS cable from the keyboards L output into the Mixers Stereo L(Input) so basically its summing up the Left right signals in Mono mode...I have also tried using 2 TS cables from the keyboard out left and Right an onto the Mixers Stereo L and R input channels....and in Both ways I get clear sound..... I want to know if a TRS cable can be used but my Yamaha keyboard has unbalanced signals on the outs but the mixer stereo inputs are balanced.....Previous I used a TRS to Xlr and it was creating all sought of hums and jarring after mins of play........Also Can I introduce a passive DI then the TRS to XLR should work....
Psr S900 rear view
- Epm 12 mixer
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It looks to me like both the keyboard and the mixer have unbalanced 1/4" connections for Left and Right stereo. They also look to be auto switching between 1 cable for combined mono and 2 cables for stereo.
My fist thought would be to use TS 2 conductor cables just like you have. Either 1 for mono, or 2 for stereo. But want to use a single cable for stereo, right? I don't think you can, unless you have a Y split at each end. The mixer's stereo inputs are not balanced and not TRS stereo.
My fist thought would be to use TS 2 conductor cables just like you have. Either 1 for mono, or 2 for stereo. But want to use a single cable for stereo, right? I don't think you can, unless you have a Y split at each end. The mixer's stereo inputs are not balanced and not TRS stereo.
I think you might be OK to go unbalanced to balanced but depends on cabling/grounding. I usually got away with it. The answer lies in the circuit on the mixer but I predict the SC folks expected this would happen and you will be fine. TRS to XLR is usually fine EXCEPT running stereo. Not cool. Is there is a snake involved? Not sure why you don't want to just run 2 cables...
The mixer uses TRS sockets for inputs and outputs. If you use TRS, connect the Ring to the Sleeve at the keyboard end to avoid stray noises.
Yeah, looking again - the stereo inputs are balanced, so you can use either TRS or TS. But you can't run in stereo to a single connector. You need 2 cables for stereo, either balanced or not.
Hi Sam thanks for the quick one, but yes I do use 2 cables Ts and insert it into the L and R ....but I'm so confused with these mono and stereo cables...so I be using trs cables instead or just TS is fine...
I did check the manual and they claim these inputs are balanced...but the question is can I use 2 TRS Jack's instead of TS
Also if I have to use a TS to xlr, will I have to introduce a passive DI Box in between...being the keyboard being unbalanced
Don't "have to" but it's often a good idea. The XRL inputs are meant to be mic level and balanced. The can handle a line level unbalanced signal, but they can get over driven. They also have a low input impedance, which may or may not make the keyboard happy. Doesn't hurt to try.
Line level 1/4" is your best bet.
Line level 1/4" is your best bet.
Short means to connect directly together. As in a "short circuit". Here not meant as a bad thing.
I did try to to xlr and the keyboard sends jarring signals out to the mixer and we can't perform any further...switching to line level TS didn't create any problem
Good to know. Sounds like you were over driving the inputs. It's best to stay at line level if you can. How far is the keyboard from the mixer?
About 6 ft distance between keyboard and mixer if I use line level...if I use xlr the 15 ft because the mixer is kept under lock and key for others not to tamper the settings so we build a wall mount with xlr interfaces for easy access between the keyboard/mics and mixer
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6ft is very short, not a problem for unbalanced line level. If you do want to use the XLR inputs, you should probably use a direct box or two. You can even buy stereo boxes.
While you CAN use XLR I would use the stereo inputs. EQ/AUX/FX is tied together and only one fader to move. Less chance something will get messed up.
Agreed, 6ft should be cake to run unbalanced. Far less chance for interference.
Agreed, 6ft should be cake to run unbalanced. Far less chance for interference.
Darrensound
It seems Your Keyboard has Unbalanced Stereo TRS on the right connector.
So, two signals in phase L & R, or +L & +R or Hot L & R.
If you connect this TRS-TRS cable to the mixer Left input (usually for outputting the 2 channels in mono), since the input is balanced, it is expecting a out of phase signal on the Ring. COLD signal.
But You have two in phase signals. One on the Tip Hot L and one on the ring Hot R.
They will cancel each other, since the COLD signal is inverted inside the mixer and then summed. You need always two cables unless You alter either the Keyboard or the mixer.
What You can do to minimize noise is to create a pseudo-balanced or impedance balanced out on the keyboard, but you would drop the TRS stereo connection on the right connector, unless you would fit two more TRS jacks or use a chip like the DRV134 for creating the balanced connection. In either case, You need two cables. One for L, one for R.
It seems Your Keyboard has Unbalanced Stereo TRS on the right connector.
So, two signals in phase L & R, or +L & +R or Hot L & R.
If you connect this TRS-TRS cable to the mixer Left input (usually for outputting the 2 channels in mono), since the input is balanced, it is expecting a out of phase signal on the Ring. COLD signal.
But You have two in phase signals. One on the Tip Hot L and one on the ring Hot R.
They will cancel each other, since the COLD signal is inverted inside the mixer and then summed. You need always two cables unless You alter either the Keyboard or the mixer.
What You can do to minimize noise is to create a pseudo-balanced or impedance balanced out on the keyboard, but you would drop the TRS stereo connection on the right connector, unless you would fit two more TRS jacks or use a chip like the DRV134 for creating the balanced connection. In either case, You need two cables. One for L, one for R.
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