Hi Sean, it is of course your choice if you give up on that if it is not important for you. However I still would like to make sure other people know that this is supposed to work and does work for many people. You are the only one I ever heard from for whom it did not work.

So for those people for which this would be a deal breaker they should not shy away from the instrument because of your report. They should at least try it out themselves and will with all likelihood find it does work for them.

Sean which store did you visit? We will send someone in there to teach the staff how to use this important feature. In their defense, it is not something that gets demoed much in stores (unfortunately). They are afraid to leave the microphone unsupervised, if get my meaning). But we’re willing to make that training happen.

Not only can you plug a Microphone in for the Vocoder but you can use it as a tempo source... place that Mic in the drummer’s kick drum and now they are the tempo source for your Arpeggios, tempo driven Effects, etc, plus they can become a modulation source in your synth engine. When working the Mic will sound great through the instrument... it has its own channel, it’s own Dual Insertion Effect, and Routing situation.

To assume it doesn’t work is NOT good enough. We, at Yamaha, want to replace your instrument if it is not working properly (although we don’t think that is the case). And are willing to send someone to that store location to show that staff how to support the product... so that on your next visit they can show you. And if it is true that both your instrument and theirs are defective, then, by all means, we want to replace both! asap!

Let us know, thanks...

Still no luck--just a loud hum when we turn on A/D and turn the gain up.

One other question: TS versus TRS? Are you certain about TS versus TRS? Very important difference.
TS = TIP SLEEVE (looks like regular signal cable 1/4” jack)
TRS = TIP RING SLEEVE (the male connector has a second black band) = ng

My last (long) response wasn't posted, I'm thinking maybe because I included the name of the Guitar Center store and employee who helped me and the specific product names that I've tried, mics and cables.

Since that last post was rejected, I'll sum up what I said--I listed specific models of mics tested, which were dynamic mics requiring no phantom power. And using cable that is TS, not TRS.

Also mentioned that the combination of equipment that we tried at the store did work on an FA-08.

Please call Yamaha Customer Support 714.522.9000 Mon-Fri 8:30-5:00pm Pacific Standard Time.

Just to confirm since I have been following this thread. (I am not the same Sean as the op). I recently purchased a MODX from Guitar Center afew weeks ago. Also have not been able to get the vocoder working properly until today.:D The Vocoder does work and it is most likely a cable issue. Initially after reading this thread, I suspected that the cable was indeed the issue so went to visit the store again to check everything out. Guitar center had NO Female XLR-to- male TS 1/4 in the entire store, including the one I had. The guys kept using different cables (or setups) but none of the cables were correct and none worked.

I suggested that try an adapter (Livewire 1/4" Male Adapter and connecting it to a regular Mic XLR cable) and Voila, Vocoder works!!!

The Guitar Center folks were trying to be helpful but were lost on how to get the vocoder to work. They also kept switching vocoder sounds so found that I had to constantly check the settings for make sure the Mic Input was setup correctly for whatever sound was chosen. Initially when they tried the adapter it did not work... follow @badmister advice above and it will definitely work

Alternatively, you can get a $10 mic at your local grocery-plus-stuff store that already has a 1/4" connector. At least as a cheap backup.

Also on the cable, it IS balanced. Guitar Center guy said that was required for the keyboard.

Old post but isn’t this the problem? Can’t be both balanced and TS.

The cable you want to connect a dynamic mic (SM58, for example) to the MODX for vocals/vocoder, etc.:
XLR female to 1/4” TS male

Google-it!

Most all microphones have a three wire connection - to use the MODX input two of the wires must be shorted together.
An XLR to TS cable is supposed to have one of the signal wires shorted to the ground wire. If this type of cable is then
connected to the XLR Line output of most pro audio gear, it shorts out one side of the output amplifier. This can damage
the pro audio gear in question. It would have been better if the MODX A/D inputs had TRS inputs. Then when a TS jack
was connected it would just short out one side of the input, which would not damage anything. It would just cut down the
level of the input by 3db. However sometimes you find a TRS connection used for a stereo audio signal, so in that case
with a TRS input for a mono balanced input connecting a stereo output TRS cable you would get the L-R signal, which is
extremely unlikely to be what is wanted.

Since there was mention of a hum situation it certainly smells like a mis-wiring of the cable.

Hi

I think that the issue is not related to the type of cable as I have a microphone that works with both XLR to TS and TRS cables

The reason why it doesn't work is that the preamp power seem very weak.

Testing with Sennheiser e835s:
- I need to turn the Gain knob to max and shout out loud in the microphone to hear my voice from my connected speakers and see the Level Bar in MODX Recording feature jumping high
- I need to go to A/D Input EQ and add few db gain in order to have decent sound level but with so much gain the noise is too high as well.
- Same result with both TRS and TS cables
- Sennheiser e835s is 350ohm mic with sensitivity of 2.7mV/Pa

Testing with Rlaky DM308a (a Chinese trash microphone)
- Sound level is normal when Gain knob is on 12 o'clock (middle position)
- No need for any additional gains
- Same result with both TRS and TS cables
- Rlaky DM308a is 600ohm with sensitivity of -72db (if this information is correct at all since the mic is sold for under 10$)

So...

I'm not sure now, what microphone to get since the Rlaky should have gone in garbage by now.,.. I'm keeping it only as a souvenir 😀
Need to lend more mics to test which one works the best.

Any sound engineers here that could explain the numbers from above ?

One more test from my side:

ElectroVoice N/D767a
- I need to turn the Gain knob to max and shout out loud in the microphone to hear my voice from my connected speakers and see the Level Bar in MODX Recording feature jumping high
- I need to go to A/D Input EQ and add few db gain in order to have decent sound level but with so much gain the noise is too high as well.
- Same result with both TRS and TS cables
- ElectroVoice N/D767a is 300ohm mic with sensitivity of 3.1mV/Pa

Has someone maybe tried Shure SM58 ?

I have tried an SM58 directly in tho it did feel a little quiet. Currently I have a vocal microphone and a drum mic plugged into a desk ( X18 ) and then I have the output from Bus 1 going to AD left and Bus 2 going to AD right.

I then have set up performances to use AD L/R mono and when I want the vocoder to work I mute AD Right. when I want the live kit to set the tempo I mute AD Left.

@Bad Mister
XLR to TS cables can be wired in 2 different ways: pin 3 (cold/negative) connected to pin 1 (ground/shield) or pin 3 floating. And there is apparently another option to add a resistor to the connection between pin 3 and pin 1. Could this difference in the cable wiring be the reason that a standard dynamic microphone (with XLR connector such as the SM58) works for some and not for others?

@Sean (not the op but the second Sean that joined the discussion later on): There are 2 different Livewire adapters. Which one did you use with which mic?
(a) Essential Adaptor 1/4″ TS – XLR Female (SSQXF) https://livewire-usa.com/ssqxf/
(b) Essential Hight Impedance Adaptor 1/4″ TS – XLR Female (SSQXFHZ) https://livewire-usa.com/ssqxfhz/
The DRV100 that the op tried has 600 Ohm output impedance and SM58, for example, has according to the spec sheet “Microphone rating impedance is 150 Ω (270 Ω actual) for connection to microphone inputs rated at 19 to 300 Ω”. Maybe @Bad Mister could clarify whether the output impedance is of relevance?

GuitarCenter has both, that’s why your post (@Sean) is not clear to me:
(a) https://www.guitarcenter.com/Livewire/Essential-Adapter-1-4-TS-to-XLR-Female.gc?rNtt=Livewire%20essential%20Adaptor%20&index=10
(b) https://www.guitarcenter.com/Livewire/Essential-High-Impedance-Transformer-Adapter-1-4-TS-to-XLR-Female.gc?rNtt=Essential%20Hight%20Impedance%20&index=2