A370

For the three and more legged things
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Ali Tait
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#1 A370

Post by Ali Tait »

Hi Chaps,
I've noticed on powering down the amp,it takes a while for the supply caps to discharge-not surprising with 100,000 uF a side!-and just as the caps are discharged,there is clicking and popping/beeping noises from each speaker.It's not the same through each channel i.e. each channel does it's own thing .Whaddaya reckon? Smoothing caps on their way out perhaps? Any thoughts advice gratefully recieved.
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Ali Tait
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#2

Post by Ali Tait »

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Nick
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#3

Post by Nick »

May just be the tollerances on the caps means one side drops faster than the other. And the output devices may not be matched outside their operating current range.
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ed
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#4

Post by ed »

Hi Ali

try the question on diyaudio, there is a lot of experience of mf over there and you'll probably get a response very quickly.

Have you got a circuit for the power supply, I'd love to see it if you have.
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#5

Post by SimonC »

After seeing it in action at the weekend I think its just it releasing its stranglehold on the local power station and the slight thump is the rest of the system (and your house) breathing a sigh of relief.

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#6

Post by ed »

Nick wrote:May just be the tollerances on the caps means one side drops faster than the other. And the output devices may not be matched outside their operating current range.
gpwm

my experience of mf is littered with memories of clicks and pops

oh yeah, and a word to the wise....I lost a transformer in one of my stats a while back, and the only thing I could put it down to was residual clicking when I turned the amp off....needless to say I sorted the turn-off clicks pdq
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Ali Tait
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#7

Post by Ali Tait »

Thanks Gents.I'll try on diyaudio.Dave,have you replaced the blown fuse in your mains lead yet? :D
Simon,you may be right,I'll have to build it it's own substation!
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Ali Tait
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#8

Post by Ali Tait »

Sorry Ed,I don't have the power supply diag.
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Dave the bass
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#9

Post by Dave the bass »

Ali Tait wrote:Thanks Gents.I'll try on diyaudio.Dave,have you replaced the blown fuse in your mains lead yet? :D
Simon,you may be right,I'll have to build it it's own substation!
Yep all done, I'll do an invoice for you.... :wink: :D

I'll waive the charge for fuse damage if you send me a box of good quality Scottish electricity though!

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Mike H
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#10

Post by Mike H »

Gordonus Bennettus...
 
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Ali Tait
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#11

Post by Ali Tait »

Got a reply on diyaudio from a bloke who used to repair MF amps! You were spot on Nick.It's the pos and neg rails discharging at different rates.Normal and nowt to worry about thankfully.Been advised to change the 'lytics,which I was going to do anyway.This amp does explosions better than any other amp I've heard! :D
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Mike H
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#12

Post by Mike H »

You can't turn the speakers off then?



Sorry if that seems a bit obvious...
 
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Ali Tait
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#13

Post by Ali Tait »

I'm using the amp in my system up in Scotland,with some B&W P5's on the end of it.I was really more worried about a dodgy electrolytic taking out one of the mosfets,as I understand these are unobtainium now.From what I've been told,it looks like the bias has been turned down in mine to let it run cooler,as the bloke says it should be running hotter than it is! :shock:
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