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Gregor

Jands sr3000 power amplifier repair?

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Hi all as the title says im repairing a jands sr3000 power amplifier. was wondering if anyone had any info on this old work horse. I have not powered it up yet but believe  it has 1 functional channel, the faulty ch has melted mj15024/5 output devices, the circuit board is not burned or damaged luckily. this is my first rebuild of a class h amplifier. I do have experience in class ab topology. it runs 75-0-75v and 150-0-150v stepped output stages. a schematic would help alot. Greg

20170417_102645.jpg

20170417_102655.jpg

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The faulty channel is now fixed, Out of the 16 output devices I was able to match and reuse 8 devices and I replaced the other 8 with new. I also replaced the pre drivers and some diodes . I managed to obtain a copy of the schematic and owners manual from the original designer Mr Doug Ford, a very helpful guy. Cheers Greg

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Hi Simon, yes it sounds fine no complaints, although I have only listened up to a few watts output. it is rated to 630wrms both ch @8r continuous sine output. 

Greg

jands sr3000.jpg

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Guest ashman

hi greg,

i have one of these amps that has failed.

three of the eight fuses on the input board have blown.

there is no output, but it fire up and the thermo fans run through their cycle.

my electronics is limited, are you interested in the service and repair of this beastie?

cheers ash

methanol3(at)gmail(dot)com

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Another sr3000 saved from the scrap heap, these amplifiers require the output transistors to be kept tight, Ashes amplifier needed a good 1/3 turn on all the screws to tighten them up. this was the reason 3 of the output transistors failed causing a number of drivers to fail as well. these amplifiers do sound very nice. Greg

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Hi Greg,

I have an SR3000 and one channel has appeared to have failed also.

I have swapped input leads and speaker leads and it confirms channel A is only providing the faintest whisper of audio.

a few questions of I may...

Is it possible to obtain the schematics? You suggested the chap above but no details are attached.

is the amp worth fixing given current retail value of the amp? (how much is it worth)

I love the quietness of the amp and would like to repair if feasible.

Thankjs for your help in advance.

 

cheers

Dave

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Hi Dave pm me your email and I will send the schematics. Greg
Its quite a tricky amp lots going on.
If you decide not to attempt repair I may be interested in buying it.

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Hi dave, I have sent the schematics.

Greg

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Hi Greg,

I have also acquired one of these with a dead channel, could you please share a schematic?

cheers

andy

[email protected]

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