abbey road d enfer

Re: mid/side splitter/combiner
« Reply #40 on: August 13, 2014, 04:42:42 PM »
Nothing wrong with the circuit. Where is it connected in the system? You mention diff amps; where are they? Can you draw a diagram of your system , including the type of connections (balanced/unbalanced)
>The diff amps are connected via a card slot and are floating above the main board on the sides. The dotted green and black lines was the original connection to the main board.
>Please ask if something isn't clear.


I suspect there's something wrong in the implementation of the difference circuit. You need to check that it's in conformity with the schemo.
Who's right or wrong is irrelevant. What matters is what's right or wrong.
"The important thing is not to convince, but to give pause for thought." (B. Werber)
Star ground is for electricians.


Zander

Re: mid/side splitter/combiner
« Reply #41 on: August 13, 2014, 05:01:49 PM »
I suspect there's something wrong in the implementation of the difference circuit. You need to check that it's in conformity with the schemo.
> Checked twice already. But will triple check tomorrow. Measured all voltages. It seems like when only the L channel is applied it's about right but when the right is it isn't. So maybe it's the inverting (U1A) stage? Just guessing here...


Zander

Re: mid/side splitter/combiner
« Reply #42 on: August 14, 2014, 01:31:45 PM »
You need to check that it's in conformity with the schemo.

>The connection is conform with the schematic. I'll take the circuit out and check if I can find something faulty with the unit as configured originally.

Zander

Re: mid/side splitter/combiner
« Reply #43 on: August 15, 2014, 02:08:36 PM »
Swapped the outputs the MS circuit to check if the problem was still there. It is.
I then took it out to make sure everything was working as per original intent. It does...

Anybody an idea what to do next?



abbey road d enfer

Re: mid/side splitter/combiner
« Reply #44 on: August 15, 2014, 11:32:33 PM »
Swapped the outputs the MS circuit to check if the problem was still there. It is.
I then took it out to make sure everything was working as per original intent. It does...

Anybody an idea what to do next?
You need to check the gain accuracy of both sections of the "S" section.
Inject a signal into Lin. Measure level at pin 1 of U1. Measure level at pin 7.
Inject signal into Rin. Measure level at pin 7.
You need to make these measurement with good accuracy.
It is possible that the cumulation of tolerances on the resistors create enough deviation.
Who's right or wrong is irrelevant. What matters is what's right or wrong.
"The important thing is not to convince, but to give pause for thought." (B. Werber)
Star ground is for electricians.

groselicain

Re: mid/side splitter/combiner
« Reply #45 on: September 12, 2017, 01:52:42 PM »
My version:



Jakob E.

Jakob, since photobucket isn't allowing me to see what you posted, is the matrix shown in the attached document pretty close?

gyraf

Re: mid/side splitter/combiner
« Reply #46 on: September 13, 2017, 10:26:13 AM »
Yes, the same idea.

Jakob E.
..note to self: don't let Harman run your company..

groselicain

Re: mid/side splitter/combiner
« Reply #47 on: September 13, 2017, 11:40:36 AM »
Thanks so much Jakob!