Rivera 55 12

[JC@]

I would need a schem if possible.
Also, I've heard that there are mods to control the ammount of boost on both channels. As it is right now (all stock), the jump is too big. Is there any web page covering this issue?
Thank you

[JC@]

I've found a copy in the net, but the quality is a bit low...
Still looking for the mods.

[Bob M.]

I have a friend with this very amp model and he says the exact same thing about the boost in both/either channels. He's asked me if I can back it down a bit. I haven't looked into it yet as I don't have a schematic for this model. If you 'break the code' on this, please let me know (and I'll do the same).

Thanks,

Bob M.
lumetz@earthlink.net

[JC@]

I have a friend with this very amp model and he says the exact same thing about the boost in both/either channels. He's asked me if I can back it down a bit. I haven't looked into it yet as I don't have a schematic for this model. If you 'break the code' on this, please let me know (and I'll do the same).

Thanks,

Bob M.
lumetz@earthlink.net

I will, but at least we need a schem. The one I found is almost unreadable

[JC@]

Does anybody know how to contact Rivera amps?
On their web there are links to their dealers only.
I would need a schem for the 55-12 combo.

[NPB_EST.1979]

The website has it right at the bottom of every page.

818.767.4600

I was able to talk to Paul Rivera Jr. whenever I called this number.

I have a R55-12 as well, and would LOVE to be informed on your progress and strategy.

[JC@]

Thank you for the phone info.
I am trying to remember how I "solved" it but anyway it wasn´t the perfect solution.
If I recall right my solution was putting a voltage divider one resistor being a trimpot, and an optocoupler to activate it without noise when the more gain "channel" was engaged. I can't remember where did I took power for the optocoupler, maybe it was from a relay or led status. It worked pretty well actually, BUT for some reason it acted a bit like a balance between gains, that is, the trimpot had a narrow point where it acted properly.