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AC hum with single supply and splitter

Martin mayhead

New member
I just got my Fosi Audio v3 mono block package - 2 amps with a single 10A supply, DC filter and splitter cable. I have to say I am quite disappointed because there is a mains hum (50Hz in the uk) that is clearly audible. And if one amp goes into idle before the other then there is a buzz. Obviously there are some nasty interactions through the common supply which a single DC filter doesn't address. I don't think Fosi Audio should be selling this package as it is because it is clearly sub-standard.
I'd like to know from he manufacturer how they're going to fix this issue for me and others that may be experiencing it.
 
I have today the same problem. 1 month pleasure and a terrible hum sound

This is very bad and I am not happy about it!

I think the package 2x V3 is not totally tested before release.and when I turn my Amplifier of and after 10 min the v3 turn off. En in the evening (the Amplifier is off, one of them are turn on) this a big bug in the power unit.
 
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@customer support - are y9ou going to respond to this or my emails please? I am very disappointed with your (lack of) response so far.
 
I have returned the fosiaudio v3 package back to Amazon. I was not happy with a new product and did not work properly.
 
I've replaced the 10A single supply, filter and splitter that came in the package with 2 Aiyima GAAN 48V 10A supplies, 1 for each v3, and it all works really nicely now. No hum, no triggering each other on/off and no turn on/off pop. I kept the amps and I'm trying to sell the Fosi supply. I am fairly sure that a pair of the Fosi supplies would work just as well as the Aiyama's but you can't buy them outside of a package in the UK. In truth a pair of 48V 5A supplies should also suffice.
I'm disappointed that Fosi haven't responded to this or to the negative feedback I have had to post on eBay as the result of their dire (non-existent) customer support.
 
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