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I recently purchased this amplifier off eBay just to see what the quality was like, and it has a ferocious buzz, audible even when playing music at normal listening volume.
ToidsAudio was kind enough to recommend I post this here in case anyone can offer some help or advice.
I haven’t opened the unit yet as I am waiting to see what they say (will they accept a return if I open it and can’t fix it?) but I don’t mind playing around with it if it seems fixable.
I have attached photos here of the inside, taken from the eBay posting (I have concealed the sellerID for now) and there is a youTube video so you can hear the problem.
Any advice would be greatly appreciated. I don’t want to post it back to China if it’s a simple fix. The only obvious thing I can see is that the mains GND pin is not connected to anything.
Another symptom: when I touch the RCA inputs on the back the speaker goes ‘BANG!’ but when I touch the RCA inputs on my very quiet amplifier there is no audible response from the speaker at all.
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That’s a hard one to even hazard a guess, especially without actually seeing the one that you have.
Observations:
Looks like it’s something someone put together, ie, not a “factory” unit. The box looks like a 3D print. As such, there’s no shielding.
I like the fact that they twisted the wires, but I’m not sure that the routing of the power wire is a good one as it basically wraps around 2/3 of the board. (A possible source of the hum)
The stock photo looks clean and neat, but I still reserve further comments until such time as you share your own photos. And as you said, you are waiting on resolution, so I’ll wait.
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Thanks for the input.
The case is actually decent aluminium, so there is definitely metal all around.
Another symptom I forgot to mention: when I touch the RCA inputs on the back the speaker goes ‘BANG!’ but when I touch the RCA inputs on my very quiet amplifier there is no audible response from the speaker at all.
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It doesn’t appear that the case is grounded. Is it? It looks like there is nothing from the power input grounding the case. If you are not sure what I mean, check out this part of the video:
Let me know if it is not there.
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I also hate to be the bearer of bad news, but this looks to be a clone. Take a look at the capacitors on yours versus what should be on the board. It is easiest when you look at the two big capacitors. The clones will use inferior parts, like this one appears to. Just looking at the board I can see quite a few parts differences. This is a clone bought from China – it is not a true Ice Power board. I would ask for a refund. Then just buy the genuine amplifier from Parts Express and this case that comes with all the wires. Out of curiosity, how much did something like that cost?
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It cost me AU$230/US$175 delivered. I agree, the case is clearly ungrounded (in their photos) and it looks like a clone. Still, I had high hopes for it.
The problem with buying from Parts Express is the horrendous cost of shipping from the USA. It might be cheaper to buy them from the factory in the Netherlands.
Anyway, thanks for your help!
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Oh I understand. I have the same problem if I’m buying from other countries as well. I would definitely look to find a supplier outside the US, that has it. I’m sure you can find them. I’m not really sure of who sells Parts in that area.. but yeah, it’s definitely a clone and ungrounded. Grounding it might take care of some of the issues. But in the same instance, you’ll never get the quality that you thought you were getting from an ice powered. board
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Well, my curiosity got the better of me so I opened the case. You wouldn’t believe it but when I got the case open I found that it was grounded! I also tested that all the inputs and outputs were isolated from the case correctly and got impedances of 100K – 1Mohm.
I disconnected the GND wire and the buzz disappeared – almost – completely.
I’ve put up a new video to show the effect. It was quite dramatic. There is still a slight hiss but it is inaudible from more than 30cm away from the speaker and could be caused by all the fluorescent lights in my workshop and a noisy mains power source.
I’m not sure if this indicates that the power points in my house aren’t grounded, or if there is another problem somewhere, but I am very happy with the board as it is.
I bought this as a cheap option, conveniently preassembled, to see if it would be worth buying more expensive original boards from a reliable supplier, and if the ‘real’ ICEpower boards are even better sounding than this clone then I am very keen to get my hands on some!
Thanks for your help with this! Much appreciated.
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@mikey wow, the photo fooled me. Meaculpa.
Glad to hear you found the source of the hum, but that’s really perplexing. I’m not up on you region’s electric. What is it, 120, 240, single phase? Just curious.
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@tvor-ceasar 240V 50Hz, single phase. It is not uncommon for homes in this country to be ‘unearthed’ meaning the earth point of the mains sockets are not actually connected to anything. I’ll have to get them tested next time I have some electrical work done.
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@tvor-ceasar 240V 50Hz, single phase. It is not uncommon for homes in this country to be ‘unearthed’ meaning the earth point of the mains sockets are not actually connected to anything. I’ll have to get them tested next time I have some electrical work done.
So your connections should be similar to ours, Hot, Neutral, and Earth Ground. If you read the resistance between the Neutral and Earth Ground, it should be extremely low – almost a direct short. If you get nothing / extremely high (megaohms), then you most likely do not have Earth Ground. Obviously you should double check this with someone familiar with your electric system.
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