Hello,

I have 3 other devices (Novation Bass Station II, Yamaha PSR E-443 and Yamaha DJX-II) which I would like to connect to my Motif XF’s A/D input.

Normally I wanted to buy a real audio interface, but due to different reasons,
I need a work-around until that.
(I’m still living in a small flat where my “Studio possibilities” are limited.)

I was thinking about some kind of audio splitter where I can connect my 3 other keyboards/synths.
On Amazon I found this one:
http://www.amazon.com/Belkin-Rockstar-Multi-Headphone-Splitter/dp/B00E9W11QM/ref=sr_1_4?ie=UTF8&qid=1448462377&sr=8-4&keywords=belkin+rockstar

Sure it’s not professional, but it might be enough for an “advanced beginner” like me.
The Motif XF is currently connected to my PC via USB and SPDIF.
(On the drawing it is described better.)

All other devices are/will be connected to the PC via USB as well.
Their sound would go into a splitter which is connected to the XF via AD/input.

So in theory it should be possible that the XF controls the other 3 devices
and that the sound comes out through the speakers.
As far as I know this splitter supports the feature that sound can be played from
more than 1 source at the same time.
(E.G. Rhythm of the DJX-II, Bass of the Bass Station II and chords of the PSR-E443
- at the same time)

What do you say?
Should that be possible as some kind of interim solution?

Thanks for any help!

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A splitter is, not surprisingly, meant to accept a single input and split it into two or more outputs. While in some cases a splitter can be used in reverse as a combiner, there are usually several reasons not to do that.

What you want is a mixer. Yamaha and other companies make some reasonably priced ones that should do the job. Be aware that the XF’s A/D Inputs are unbalanced, and require the connections to be made with TS plugs.

For your purposes, you might consider a passive (unpowered) line mixer.

ART makes an inexpensive passive mixer with four stereo inputs. About $50 online.

meatballfulton - 27 November 2015 11:46 AM

ART makes an inexpensive passive mixer with four stereo inputs. About $50 online.

The link is slightly mangled. This link should work:
http://artproaudio.com/artcessories/mini_mixers/product/splitmix4/

Hello and thank you for your replies!

I already ordered this audio mixer: Rolls MX 41b, a 4 channel stereo mixer.
(It should come today or on Monday)

Some guys write that they opened its case and removed the 8 resistors
in order to achieve full gain.
I’ll make a mental note of that.

Regarding the current cable which is plugged in the XF’s A/D input:
I’m not really sure if it’s an unbalanced one.
It has 2 mono 6.3 mm jacks and one stereo 3,5 mm jack.
It looks similar to this one:
http://www.amazon.com/Hosa-CMP153-Cable-Inch-Dual/dp/B000068O3C/ref=sr_1_8?ie=UTF8&qid=1448704782&sr=8-8&keywords=unbalanced+6.3+mm
(This one should be 100% correct?)

I noticed that when I haven’t plugged my cable in the A/D input,
there is absolutely no audio signal on my soundcard’s input.
(This is correct and logical of course).
When I plug in my current cable into the A/D input,
I can clearly see there is signal on my soundcard’s digital input.
(I use an EQ on this input and clearly see some signal coming from the Motif XF)
No idea if this is correct or if it can be a “balanced/unbalanced issue”.
I can’t hear any noise, but can clearly see the signals.
(Doesn’t matter if the 6.3 mm cable is plugged in an external device or not.)

Best regards

Raven80 - 28 November 2015 07:12 AM

Hello and thank you for your replies!

I already ordered this audio mixer: Rolls MX 41b, a 4 channel stereo mixer.
(It should come today or on Monday)

Some guys write that they opened its case and removed the 8 resistors
in order to achieve full gain.
I’ll make a mental note of that.

The purpose of the resistors in a passive mixer is to isolate the inputs from each other, and it protects the output stages of each source (the synths being connected). Removing the resistors defeats that - it would effectively make the mixer, when its level controls are turned fully up, like a splitter used in reverse.

If the level isn’t sufficient with the mixer’s input controls turned all the way up, the output levels maximized on the synths, and the XF’s A/D Input Gain control at maximum, then the XF’s Utility mode mic/line setting can be changed from “line” to “mic”. If you do that, start with all the controls turned down and bring them up only as needed..

 

Raven80 -

Regarding the current cable which is plugged in the XF’s A/D input:
I’m not really sure if it’s an unbalanced one.
It has 2 mono 6.3 mm jacks and one stereo 3,5 mm jack.
It looks similar to this one:
http://www.amazon.com/Hosa-CMP153-Cable-Inch-Dual/dp/B000068O3C/ref=sr_1_8?ie=UTF8&qid=1448704782&sr=8-8&keywords=unbalanced+6.3+mm

The “mono” 6.3 mm (1/4") plugs are TS type, which is correct.

Hello,

I made the first tests.
The loudness itself is ok compared to the Motif XF’s.
Since I only hear the XF tones coming from the digital output,
I can compare the loudness very well.
(The master fader of the Motif XF is 0)

When two devices are connected to the 4 channel mixer,
their loudness levels are a bit lower.
This can be corrected by turning/spinning the A/D input gain.
I tried to change to MIC, but I think I don’t need it that loud.

But what still bothers me a bit are the idle frequencies coming from the A/D.
When nothing is plugged there, my EQ shows nothing.
As soon as I connect the cable, I see frequencies.
(You can see it on the attachment)
It doesn’t matter if another device is connected.
(I made the screenshot when the cable was not connected to the mixer.)

I just want to avoid that when I make a complete song louder,
the idle frequencies will become hearable.
(Right now I can only hear them when I boost the volume of my stereo.)

An alternative solution (no idea if this is handable):
I just use the A/D input and mixer to test and create sounds.
Let’s say combining two voices of two other synths, using an XF effect etc.
Once I spot something really interesting, I can record the sounds independently of the A/D input (by connecting the other synths to a soundcard or an audio interface.)
Later I can load the recorded WAV files into the Motif XF
and use the effects afterwards to re-create the sounds.
(I should write down all the effect settings of course.)
Sure it’s more work, but it would avoid having noises/parasitic frequencies.

Edit
Perhaps I could also use some kind of “noise removal”.
But I would need to test this first.
I can record these idle frequencies and then try it.

Best regards

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