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Re: Mix Out Noisy/Distorted

Posted: May 30th, '16, 08:41
by dinsync
when i run the nava through a compressor i can hear it clearly, it sounds like switching noise. That could be from the transistors or the sequencer I suppose. Since we have all the voices triggering at power on, we don't really have to worry too much about the power on thump do we ;) so not placing those two resistors for the moment is the best workaround

Re: Mix Out Noisy/Distorted

Posted: May 30th, '16, 09:18
by comboy
e-licktronic wrote: Are both channel L and R distorted ? You should measure 0v to Q79 collector
Try to replace Q79.
both mix outs are affected.
And since everybody I talked with so far has this problem I don't think it is a problem related to my specific transistor.

Re: Mix Out Noisy/Distorted

Posted: May 30th, '16, 09:52
by e-licktronic
comboy wrote: both mix outs are affected.
And since everybody I talked with so far has this problem I don't think it is a problem related to my specific transistor.
Try this mod in Master section:
-Unsold D195 and one side of R471
-Then solder the 1N4148 diode with R471 like on the picture
-Solder a bridge in place of D195.
Image
Image

Best regards,
e-licktronic

Re: Mix Out Noisy/Distorted

Posted: May 30th, '16, 14:05
by comboy
does not help.
as stated before I already modified my board according to the original 909 schematics to fix the error in the nava schematic.
But I still have the same behaviour as before.

Can you even reproduce the error on your unit?
Did the component change fix the issue for you?

I can measure again if I cut the right trace (I modified the traces with a piece of wire)
but I'm nearly sure I measured continuity with the DMM before...

Re: Mix Out Noisy/Distorted

Posted: May 30th, '16, 17:25
by e-licktronic
comboy wrote: Can you even reproduce the error on your unit?
Did the component change fix the issue for you?
We do not notice any distorted or noise on master out on our Nava.
Could you post a picture of your mod and a sound example of distorted Master out ?

Best regards,
e-licktronic

Re: Mix Out Noisy/Distorted

Posted: May 30th, '16, 19:53
by Rowan
I'm getting interference from the step LED's in the main output. The level of the interference is directly related to the number of LEDs lit, the more LEDs on the louder the interference.

I'm not using shielded cable to connect the master section to the IO board.

Is anyone else getting this?

Re: Mix Out Noisy/Distorted

Posted: May 30th, '16, 20:48
by housedet@comcast.net
Instead of waiting to see if we have the same issue after we complete the Master section, am I correct in thinking that we should automatically do the mod that is suggested above,(solder the 1N4148 diode with R471 like on the picture, then Solder a bridge in place of D195)? That would sure be a lot easier than de-soldering afterwards. I'd rather solder 1000 components than de-solder one :-)

Re: Mix Out Noisy/Distorted

Posted: May 31st, '16, 03:30
by e-licktronic
housedet@comcast.net wrote:Instead of waiting to see if we have the same issue after we complete the Master section, am I correct in thinking that we should automatically do the mod that is suggested above,(solder the 1N4148 diode with R471 like on the picture, then Solder a bridge in place of D195)? That would sure be a lot easier than de-soldering afterwards. I'd rather solder 1000 components than de-solder one :-)
Yes you can ;)

Best regards,
e-licktronic

Re: Mix Out Noisy/Distorted

Posted: May 31st, '16, 11:21
by housedet@comcast.net
Thank you, I will do that.

Re: Mix Out Noisy/Distorted

Posted: Jun 3rd, '16, 21:50
by drifter7508
Rowan wrote:I'm getting interference from the step LED's in the main output. The level of the interference is directly related to the number of LEDs lit, the more LEDs on the louder the interference.

I'm not using shielded cable to connect the master section to the IO board.

Is anyone else getting this?

Same here. Interference from the step leds. Not using "shielded cables".