DanWesson357
New member
I've pre-ordered two ZA3s to run in mono and will use XLR input. Which opamp should I replace, the XLR opamp or R-OPAMP or both?
Here is a simplified example of how an op-amp can be used to cancel out interference when summing the two signals from an XLR cable:
- The two signals from the XLR cable are fed into the two inputs of a differential amplifier.
- The op-amp amplifies the difference between the two signals, while rejecting any common-mode signals that are present in both inputs.
- The output of the op-amp is the summed signal with the interference canceled out.
Answerso because one of the signals is inverted it is seen as different from the other one, so it is amplified. While the random noise in both cables are seen as the same and therefore filtered out?
Yes, that is correct. The process of inverting one of the signals and adding it to the uninverted signal is called differential amplification. This technique is used in balanced audio systems to reject common-mode interference.
When the inverted signal is added to the uninverted signal, the common-mode interference is effectively canceled out. This is because the common-mode interference is present in both signals, and when the signals are added together, the interference components cancel each other out.
The audio signal, on the other hand, is not affected by this cancellation process, because the audio signal is different in each conductor. This is why the audio signal is amplified, while the common-mode interference is rejected.
The ground conductor in an XLR cable further helps to shield the signal from noise. This is because the ground conductor creates a common reference point for the two signal conductors. This helps to ensure that the common-mode interference is canceled out more effectively.
As a result of these features, XLR cables are very effective at rejecting common-mode interference and providing a cleaner and more accurate audio signal.
So, I don't have to replace the XLR OP AMP even though I will use the XLR input only in mono mode?Normally speaking, we can just replace the R-OPAMPs on two ZA3s.
No, it is not required to do so.So, I don't have to replace the XLR OP AMP even though I will use the XLR input only in mono mode?
Then why is there an OP amp for the XLR? When is it supposed to be replaced?No, it is not required to do so.
It serves as a differential amplifier. The two signal cables of the xlr carry an out of phase signal and random noise from interference.Then why is there an OP amp for the XLR? When is it supposed to be replaced?
I have a pair of ss3602 and a pair of MUSE02. I intend to run two amps mono, with MUSE02 in XLR and SS3602 in right channel. Should be fun to play with. Just waiting on the amps to ship!I've tried to change op-amps in the XLR (ss3602), it sounds much better than stock, but when you swap them in the right channel, it sounds the best. Interesting to try to swap op-amps both in the right channel and the XLR. Would there be an additional benefit in sound?
I also decided to swap the opamps in the XLR. But I would also like to change the opamp(s) for the Sub Out.I have a pair of ss3602 and a pair of MUSE02. I intend to run two amps mono, with MUSE02 in XLR and SS3602 in right channel. Should be fun to play with. Just waiting on the amps to ship!
I connected subwoofer to the sub out of one of the amplifiers with RCA. Low frequencies are usually the same on both channels.How did you like it after changing both the r channel and xlr op amps?
How did you connect you sub in mono mode?
I'm also interested in knowing what kind of of improvements will changing the 2 sub op amps will do.
Thank you.
Very informative, thanks! Got two ZA3’s and removed left opamps and did manage to smear a bit off the grease, hope this won’t affect that one unit. Also, can you tell me if I should take out the subwoofer out opamp as I’m not using that connection on the back of the amps. I do however have my passive subwoofer connected via speaker cables to both ZA3’s, and my main speaker cables are connected to and through my subwoofer. Your advice would be appreciated.