Hello, I believe the MM/MC switch on my EAR 834p is failing. Sometimes the left channel will drop all together, and depressing the MM/MC switch a time or two will bring it back. Lately I have been noticing that unless I am depressing the switch just a little bit, I have a noticeable channel imbalance, with the left channel maybe having 80% of the volume that the left does. I do not have a balance adjust anywhere in my system, so no easy workaround.
I'm using an MM cart now and do have an external cinemag-based SUT to use when I can finally get my MC cart retipped, so I'd like to remove the switch and bypass the internal SUT all together.
Can anybody provide direction on how to hard wire to the MM section with the switch out? I have attached a picture of the twelve pins that make up the switch soldered to the board.
I'm using an MM cart now and do have an external cinemag-based SUT to use when I can finally get my MC cart retipped, so I'd like to remove the switch and bypass the internal SUT all together.
Can anybody provide direction on how to hard wire to the MM section with the switch out? I have attached a picture of the twelve pins that make up the switch soldered to the board.
I think this is the input circuit with the switch, per channel.
Both switches are either up or down together, along with those of the other channel.
This software won't show them in that way. Just remove the switch.
One jumper wire from the RCA input to the first grid is all you should need, per channel.
Both switches are either up or down together, along with those of the other channel.
This software won't show them in that way. Just remove the switch.
One jumper wire from the RCA input to the first grid is all you should need, per channel.
Attachments
Last edited:
That's what I recall and of course is a stark illustration of why most switches perform poorly in low level circuitry. (Ones that perform well long term are probably too expensive for this pre-amplifier.)
And what Rayma said, just remove and jumper or if your soldering skills are not up to snuff just jumper as he suggested and leave the switch in place.
And what Rayma said, just remove and jumper or if your soldering skills are not up to snuff just jumper as he suggested and leave the switch in place.
It's difficult to believe that anyone would use a switch before the phono stage,
but even Audio Research did this is their SP-3 preamp. Less is definitely more here.
If you don't remove the switch, make sure that it is always on the MM setting.
In this case, the jumper is shorting out the flaky switch contacts.
but even Audio Research did this is their SP-3 preamp. Less is definitely more here.
If you don't remove the switch, make sure that it is always on the MM setting.
In this case, the jumper is shorting out the flaky switch contacts.
Last edited:
Thanks everyone.
I did try a little DeoxIT in the switch and didn't help any.
Shucks...thought I managed to attach that. Should be there now.
I think I should be able to manage the switch removal and jumper OK with a little focus.
I took on my first ever DIY project this year, and choose a scratch build Aikido line stage build using Broskie boards for the power supply and signal boards. It took me forever and I'm still working on reducing hum, but it works and sounds pretty good.
I did try a little DeoxIT in the switch and didn't help any.
Shucks...thought I managed to attach that. Should be there now.
I think I should be able to manage the switch removal and jumper OK with a little focus.
I took on my first ever DIY project this year, and choose a scratch build Aikido line stage build using Broskie boards for the power supply and signal boards. It took me forever and I'm still working on reducing hum, but it works and sounds pretty good.
