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Hello all. I'm a first time poster and just found your site today. And I'm really in need of guidance with my current problem. I'm simply trying to connect two synths to one channel on my mixer. I'm out of inputs on my soundcraft epm8 and have a Kawai k4 keyboard and k4 m rack modual (the exact same synth) that I want to merge. I ran into a problem though and would like to know if I have a potential issue of damage. My signal flow is the following:
ch 1 and 2 inputs on my mixer are 1/4 inch balanced. I then purchased two of these Y cables for the merge:[="http://www.hosatech.com/products/340593/14_in_TRS_to_Dual_14_in_TRSF"]1/4 in TRS to Dual 1/4 in TRSF - Hosatech[/]="http://www.hosatech…"]1/4 in TRS to Dual 1/4 in TRSF - Hosatech[/]
Using all balanced cable for the synths, I take the left out of the 1st synth and connect to the first female input on the Y cable and plug the male end into ch 1 on the mixer. No problem. Then I take the Right out of the 1st synth and plug it into the second female input on the Y cable and plug it into mixer ch 2. No problems and stereo panning, etc is perfect with a nice clean, strong signal. In summary, Ch 1 on the mixer is the left out on synth 1 and ch2 on the mixer is right out on synth 1. Again, no problems. Then this problem occurs: I do the exact same procedure on synth 2 using the second female input on the Y cable. Now the two synths are merged on ch 1 and 2 on the mixer. I hear the second synth for about 5 seconds and then the sound cuts out to a faint and barely detectable level and the only way to get the signal back up to a good level is to pull back the balanced cable one "click" or ring. Pushing the balanced cable in all the way kills,the signal but the other synth, synth 1 is fine. What did I do wrong? If I keep the second synths balanced cable plugged in only half way, it works fine. I also tried a unbalanced cable and also needed to pull back the cable half way out to hear the signal. BTW Hosa also,makes this cable too:
[[url=http://="http://www.hosatech…"]1/4 in TS to Dual 1/4 in TSF - Hosatech[/]="http://www.hosatech…"]1/4 in TS to Dual 1/4 in TSF - Hosatech[/]
Is the TRS causing the issue perhaps? THANK YOU for your time in reading this. Sincerely, Jeff

Comments

KurtFoster Sat, 04/20/2013 - 17:28

Jeff

y cables are great for splitting the output of a device but not meant to merge 2 inputs. you could actually damage your gear. what you are doing is connecting the output of one piece of gear to the output of another piece. no good!

you need a sub mixer. there are plenty of inexpensive [[url=http://[/URL]="http://www.amazon.c…"]passive 1/4" mixers available[/]="http://www.amazon.c…"]passive 1/4" mixers available[/].

get one of those.

lotuac Sat, 04/20/2013 - 17:37

Kurt: Thanks for your time in reading that! I'm about to return the y cables I purchased and I did just buy a ART splitmix4
[[url=http://[/URL]="http://artproaudio…"]ART Pro Audio[/]="http://artproaudio…"]ART Pro Audio[/]
However, I also tried to put in both left and right outputs from the synths, input 1 is L, input2 is R for the first synth then input 3 is L and input4 is R from the second synth Then run a stereo or balanced y cable from its 1/4 stereo output jack into ch 1 and 2 in the mixer and only got dual mono! I thought that because the splitmix has no pan control, all input signals are " summed " Im still learning this.....Can you tell?

dvdhawk Sat, 04/20/2013 - 22:29

Hi Jeff,

I haven't seen anything online, or in the manual I've found on the web, that suggests the Kawais have balanced 1/4" outputs. Very few synths do. [Problem #1]

Unless you've got different information that positively states they're balanced outputs, you should be using standard TS instrument cables.

The Soundcraft Line inputs can handle unbalanced TS or balanced TRS signals, and mechanically senses which you're using. But it sounds to me like you're sending it a mis-matched assortment of unbalanced signals (intended to be TS 1/4") through TRS. As soon as you plug the TRS into the Soundcraft it is designed for the Ring to be inverted (opposite phase).

You would get very different results with the TRS to TRS Y cables going to the inputs on the Soundcraft - depending on whether the Kawai shorts the Ring to the Sleeve, Ring to the Tip, or just ignores it and lets it float. The problem would be compounded by panning and different synth patches, and how different/similar the signal was coming out the Left/Right outputs.

You're not using the Insert jacks for inputs are you? (if you are, you shouldn't be)

lotuac Sun, 04/21/2013 - 07:47

Good morning DVD hawk (and others)
Actually, if the Kawai did have balanced outputs, I would not be surprised at all! (They are unbalanced) Kawai created what was probably the most unique and under appreciated synths in their short time. I'm not using the insert jacks but I thank you for your explanations and break downs of the types of connectors, cables etc. I think I've just found my new home here at the forums......Take care, Jeff