UNISON RESEARCH Smart 845 Monos

Psilonaught

Wammer
Wammer
Aug 16, 2007
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Saffron Walden
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James
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Why not consider a line magnetic 845 integrated.

I have an Auralic Aries G2 and would never consider using its volume control, you must be mad.

Almost as mad as considering an ancient Graaf. How reliable is an old Italian amp going to be lol...
 

MF 1000

Now That's What I Call Bass !
Wammer Plus
Apr 5, 2011
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Caego
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Keith
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My mains is definitely AC - as is every house in the country connected to the Grid! I suspect the buzzing was more related to Alternating Current passing through a poorly wound (or bound) mains transformer.

However, I was probably just unlicky with mine. Had it been new, it'd have gone straight back to the dealer and hopefully to Graaf for replacement of the noisy culprit. Peter
Your not really understanding the concept of low level DC injection into an AC mains supply. It can and does occur from SMPS power supplies and can affect amps, CD transport, DACs etc
 

hearhere

Wammer
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Apr 9, 2013
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Peter
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Your not really understanding the concept of low level DC injection into an AC mains supply. It can and does occur from SMPS power supplies and can affect amps, CD transport, DACs etc
OK, I am understanding your point but perhaps you are not understanding mine! The only electronics I had in my system while living at my London flat for over 30 years that suffered from any mains-borne troubles was the Graaf. As I said, I liked its sound apart from the constant buzzing from its transformer that I suspect was caused by the AC element of my mains supply agitating the wires in a poor transformer. Peter
 

rabski

Everything in moderation
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Dec 2, 2006
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Richard
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If any DC that may have found its way into my AC supply (doubtful as it was on a different ring main) and it only affected the Graaf amp, I'd point my finger towards that amp rather than the fridge! Yes, fridges occasionally cause a near-silent click through the speakers but never a continually buzzing mains transformer.
Actually, they can. The circuit for the compressor can do so, as can the 'low' setting on hairdryers. Among many other things.

Mains in most countries worldwide is AC, but DC offset is far from uncommon and it's source can be external to the home, as well as within it. All supplies are 'common', so being on a different ring circuit does not offer any isolation from DC offset. One of the symptoms is a degree of core saturation in transformers, and larger torroidal transformers are particularly prone to this.

Mechanical buzzing from transformers can have a number of causes, including poor winding, uneven laminations and mechanical 'looseness', but a degree of DC offset is far from an uncommon cause.