2. amps-preamps
  3. 187431-164353

Hooked up Shiit Mani incorrectly

I feel really stupid right now. I hooked up my Shiit Mani to my phono input on my Adcom GFA 555 preamp causing both my speakers to start distorting. Once I realized my mistake I shut the system down. I believe I may have damaged both my amps in the process.  Both amps are humming when turned on. What damage could of done? Any guidance would be greatly appreciated 

horsestuff

Showing 2 responses by rcm1203

rcm1203's avatar
rcm1203
69 posts
 
perkri The output of a phono cartridge is much lower than a standard line output, so it needs to be boosted for the preamp stage to be able to process it. The phono inputs on preamps and integrated amps sends the phono signal to an internal phono preamp to increase it to a line level signal. When you have no phono inputs, or a phono input with limited capabilities, an external phono amp like the Mani is used. it preforms the same function as an internal phono preamp and is intended to be connected to any available standard line input.  The OP's problem occurred because he inadvertently connected the line level output of the Mani to a phono cartridge level input that was designed for a much lower power signal. It was too much for the built in phono preamp, which probably still managed to boost it to line level just long enough to cause additional circuit overload to the main preamp.
rcm1203's avatar
rcm1203
69 posts
 
horsestuff OP  No guarantees, but amps generally have fairly robust input circuits since they are designed to work with variable volume. They might have survived the onslaught. It's definitely a good sign that the hum is absent with no input source.
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