Warwick Sonic III amp

[N_Cook]

Not the cause of the problem that it is here for repair, but I cannot return
it to the owner with this glaring potential (in both senses) fault,
presumably the same for all such Warwick amps.
One large heatsink with +75V on it and the other at -75V and 2.5mm between
the two , both mounted on standard polyester pcb with chassis standoffs well
away from the heatsinks. Discharged both before this test of course,
requires only 1.5Kg of force between the 2 heatsinks to narrow the gap to
1.5mm.
Have amp designers never seen the internals of their stuff
resonating/oscillating mounted in or on speaker cabs, especially bass amps
such as this?

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

 

[Meat Plow]

On Sun, 15 Mar 2009 14:04:12 -0000, "N_Cook" <diverse@tcp.co.uk>wrote:

Not the cause of the problem that it is here for repair, but I cannot return
it to the owner with this glaring potential (in both senses) fault,
presumably the same for all such Warwick amps.
One large heatsink with +75V on it and the other at -75V and 2.5mm between
the two , both mounted on standard polyester pcb with chassis standoffs well
away from the heatsinks. Discharged both before this test of course,
requires only 1.5Kg of force between the 2 heatsinks to narrow the gap to
1.5mm.
Have amp designers never seen the internals of their stuff
resonating/oscillating mounted in or on speaker cabs, especially bass amps
such as this?

Ran into similar design phenomena in a Berringer Euro Power powered
mixer. Left me sitting scratching my noggin wondering what the hell
were they thinking.

 

[Arfa Daily]

"Meat Plow" <meat@petitmorte.net> wrote in message
news:2lhalr.gu5.17.1@news.alt.net...

On Sun, 15 Mar 2009 14:04:12 -0000, "N_Cook" <diverse@tcp.co.uk>wrote:

Not the cause of the problem that it is here for repair, but I cannot
return
it to the owner with this glaring potential (in both senses) fault,
presumably the same for all such Warwick amps.
One large heatsink with +75V on it and the other at -75V and 2.5mm between
the two , both mounted on standard polyester pcb with chassis standoffs
well
away from the heatsinks. Discharged both before this test of course,
requires only 1.5Kg of force between the 2 heatsinks to narrow the gap to
1.5mm.
Have amp designers never seen the internals of their stuff
resonating/oscillating mounted in or on speaker cabs, especially bass amps
such as this?

Ran into similar design phenomena in a Berringer Euro Power powered
mixer. Left me sitting scratching my noggin wondering what the hell
were they thinking.

Well Meat, you answered your own question there ! It was a Behringer, so
they weren't thinking at all ... !! d;~}

Arfa

 

[Meat Plow]

On Mon, 16 Mar 2009 09:09:20 -0000, "Arfa Daily"
<arfa.daily@ntlworld.com>wrote:

"Meat Plow" <meat@petitmorte.net> wrote in message
news:2lhalr.gu5.17.1@news.alt.net...
On Sun, 15 Mar 2009 14:04:12 -0000, "N_Cook" <diverse@tcp.co.uk>wrote:

Not the cause of the problem that it is here for repair, but I cannot
return
it to the owner with this glaring potential (in both senses) fault,
presumably the same for all such Warwick amps.
One large heatsink with +75V on it and the other at -75V and 2.5mm between
the two , both mounted on standard polyester pcb with chassis standoffs
well
away from the heatsinks. Discharged both before this test of course,
requires only 1.5Kg of force between the 2 heatsinks to narrow the gap to
1.5mm.
Have amp designers never seen the internals of their stuff
resonating/oscillating mounted in or on speaker cabs, especially bass amps
such as this?

Ran into similar design phenomena in a Berringer Euro Power powered
mixer. Left me sitting scratching my noggin wondering what the hell
were they thinking.

Well Meat, you answered your own question there ! It was a Behringer, so
they weren't thinking at all ... !! d;~}

Arfa

Heh I don't even know how to spell the damn name. I won't work on that
crap unless it's store stock. However I was mildly impressed
(sonically) with the BX4500 amp. I won't look inside, that will no
doubt spoil things.