I am currently using a Musical Fidelity M2si integrated amp as a preamp (picture below) with another power amp I have that outperforms the integrated's internal amp. The preamp in this integrated sounds fantastic. This is probably a bit of a weird and tweaky question, but I was wondering since the amp section is not really being used it would be nice to disengage it and was wondering if I removed those two fuses located near the two large filter caps in the amplifier section would it essentially turn off the amplifiers? Unfortunately I do not have a schematic. Literature says the Class A preamp has its own separate power supply windings separate from the amp and assume the preamp power supply is located to the right of the toroidal transformer? You can see the separate wires coming off the toroid (orange/green/white). If for anything efficiency alone, I wondered if it's possible by disengaging the amp section I could reap some audible benefits in the preamp performance. Any of you experts able to tell if those fuses are related to the power amps only and not the preamp? If I went ahead and experimented and removed them and see what I get would there be any harm in that? Thanks!
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The fuses are to protect the power amplifier only. I doubt there will be any difference as the amplifier is not working or drawing current, even if it was, there is enough regulation for the pre amp supply not to notice it.
If you remove the power amp fuses you should disconnect the coax cables between the preamp and power amps, otherwise the unpowered power amp may clip the preamp output signals and intruduce heavy distortion - I think its possible to just unplug them at the white plug.
If you are not using the power section then powering it down will be beneficial by keeping the whole unit running much cooler.
Excellently clear photo BTW, and its helped by the unit being very straightforward in layout(!)
If you are not using the power section then powering it down will be beneficial by keeping the whole unit running much cooler.
Excellently clear photo BTW, and its helped by the unit being very straightforward in layout(!)
Thanks for the responses, guys. I appreciate it. I removed the fuses and removed the cable from the preamp to the amp. All worked out perfectly, the amp section is off, the unit is much cooler and all works great. Thanks again for the help!
Just for the record, it would be nice to know what Musical Fidelity model that is. No indication beyond the PCB ID is visible, as far as I can tell.
