New 6400 distorted xmit audio

Dennis Cody

New 6400 running 3.1.8 SW.  I have reported distorted xmit audio that almost sounds digitized. This happens  running 1 watt or 1KW, on a dummy load or antenna.   I have a Maestro and with mic connected to it I have the same problem. Thus same problem using computer or Maestro via RJ45 direct to 6400.   I have a friend with a 6400 and his sounds excellent, so we did on the air tests and I set all my xmit settings the same as his and nothing I do with EQ, Processor, or Mic gain changes the distorted audio.  I have tried the Flex provided hand mic which is the worst culprit, and two different studio mics.  None of the changes in Mics change the basic distorted digitized sounding audio.  In other words its not a setting of the radio. Oh and yes Mic bias is OFF.  The problem exists whether I use the Maestro via wifi, plugged into network or plugged directly into the 6400 as mentioned above.  This was to be my finest radio setup yet nothing but constant complaints on the xmit audio.   Hope someone can help or it will be going back to Austin for an exchange or refund after 5 days of shear frustration.   

thanks in advance for your advice. 

k3Tim

It's not clear if you tried connecting mic direct to radio; can you confirm?

How does your audio sound via the MONitor?

[Deleted User]

Do you have any ferrites you can put on mic cable. Possible RF getting in through mic??

Dennis Cody

Yes mic is connected directly to back of 6400.... 

Dennis Cody

Monitor audio is perfect...Good point considering it is prior to processing

Bill -VA3WTB

Dennis, it is fine your settings are just like your friends if your voices were the same.
On your EQ I would suggest  making sure all or most the sliders are under 0. Or make sure the 3 lower Freq are not above. Here is why. The EQ adds gain to the transmit audio that is not reported by the mic gain meter. So after your mic gain is set up to never bounce off the 0, once you move the EQ sliders over 0, gain is added that is not reported.

Try and see if you smoothen out the audio with this.

Dennis Cody

Thanks Bill,  I read that in a post regarding being below 0 so I set all to about minus 8. Needless to say not much fidelity but distorted audio still existed.... I also tried no processing and synthesized audio still exists.  I even out of desperation went back to Ver 2.6 on the software and no change.   Monitor audio sounds great compared to what is received on the air. 

Bill -VA3WTB

I t would be nice to hear your audio, can someone record you and post the audio? They can Audacity to record and save the file.

Bill -VA3WTB

Another thought, are you using an amp?
And you can also listen to you transmit by Turning on FDX, set up a 2nd slice and transmit from the Transverter port on slice A and listen on clice B the 2nd slice. Set both Slices to the same Freq . This allows you to listen to the audio that you transmit. Instead of listening using MON. If your TX sounds good using this test then it is good in TX.

Dennis Cody

Wow. Thanks Bill I will try that. I was using another receiver with no antenna as a monitor. I think it's fixed after finding. Correct combination of eq below zero, Mic gain and processing.

Bill -VA3WTB

Dennis, If you search, Ken did a great video on doing this test. I thought you may find the best setting. There must be a certain pitch in your voice that one of the sliders were touchy on. Many times it's the 1k and 2k that needs to be controlled more. those two will often cause distortion if they are a little to high.

I found the link for you and anyone eles wanting to do this.
https://www.youtube.com/watch?v=3s7UbKiqxAA