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opus10no1

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I'm new to this Forum , but hope to learn a lot and also pass on my HiFi/Music experiences.
I have had a pair of Expressions for about a year now (ex-demo ) and nearly fell off my chair when I first heard them, ( replaced B&W 802d's ) as did the chap demonstrating them. Absolutely fantastic.I like classical music and we listened to the storm scene from Verdi's Rigoletto ( try it if its unfamiliar ).My wife ( not known for her love of my hi-fi hobby was similarly bowled over )
They are driven by an Audio Research 75SE with absolutely no problems. The power meter never goes above 15 watts (whatever that means ) even at very loud levels.
All was well till 2 days ago when I turned the system on.
There was a loud bang that seemed to come from the 75SE ( directly in front of me, and the Expressions directly behind me so I'm pretty sure it wasn't them! )
The amp seemed ok both VDU's lit up, no smell and no smoke.
HOWEVER, the right hand speaker did not power up-the light under the front grill stayed off and only the left channel worked.
It didn't take me long to have the top off the 75 SE but could see nothing amiss-no scorch marks and no smell of burning ( in my experience a very good indicator of an electrical component burning out )
The pre-amp and CD player are the same, nothing to see or smell.
My question is, could it be the loudspeaker that's at fault ( bearing in mind they take a few seconds to power up and my bang was instantaneous ).
Again no smell from the speaker and the red light is illuminated.
I don't know how to dis-assemble them for a purely visual inspection.
I'm going to try the Anthem room correction software now ( which I should have done before writing this ) as that should show the ML's work.
However just in case there is someone out there who has had a similar experience please let me have your thoughts ( I would love to know which screws to undo for instance )
I will keep you posted
BW
opus10no1 ( not sure if one can use first names )
 

ttocs

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Welcome! and Sorry for your troubles.

There are times when I've had things disconnected and reconnected, etc, and the Expressions don't make sound even though the LED's are lit. But after unplugging them for a few minutes, they will work on the next power up.

This doesn't explain anything about your bang noise. But, you probably should unplug the Expressions for a few minutes and plug back in to see if anything changes. Also, if a few minutes on no power cord doesn't change anything, I'd unplug everything from power for at least 20 minutes.
 

opus10no1

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Welcome! and Sorry for your troubles.

There are times when I've had things disconnected and reconnected, etc, and the Expressions don't make sound even though the LED's are lit. But after unplugging them for a few minutes, they will work on the next power up.

This doesn't explain anything about your bang noise. But, you probably should unplug the Expressions for a few minutes and plug back in to see if anything changes. Also, if a few minutes on no power cord doesn't change anything, I'd unplug everything from power for at least 20 minutes.
Hi and thanks for your thoughts.
I have checked the Expressions with the Anthem Room Correction software and both loudspeakers function perfectly. This is really useful software. ( see graph)
I have discussed the loud bang at start up with my dealer and he is clear that a resistor has blown on the Audio Research 75SE and best to wait for that to be done ( no probs there as he is going to lend me a power amp till the 75 is fixed.)!
A further problem is going to be dealt with at the same time- that is a tinkling noise when replaying vinyl and only when current is flowing- not just when the phono stage is turned on.
It doesn’t happen on cd so must be the phono and my dealer tells me ( no prizes for guessing) it’s a failing valve so may as well replace the lot ( about 10 ) after about 1500-2000 hrs.
I’m going to have the pre-amp re-valved as well- about 3,000 hrs but there are only 2 to replace.
So it never rains but it pours, revalving at least 2 bits of kit and let’s see what they say about the KT 150’s in the 75SE!
I’d better find a few jobs to please herself!
79FDF681-57D5-4475-9231-C32409C90878.jpeg
 
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