On Sat, 07 Jun 2008 11:07:26 +0100, Tim Phipps wrote:
Meat Plow wrote:

Do you remember looking at the 4-63 volt, 3300uf caps in your 700D? I just
replaced the banana jack on mine and those 4 caps looked like the tops
were puffed. I pulled the top off one and there is a convexed steel cap
over the actual can under the heat shrink that makes these look domed. And
they appear also to run pretty warm discoloring the white glue used to
bond them to the pcb. The amp works fine otherwise and I've never had any
problems with it. It was formerly used to power A/V sub-woofers and had
been left on continuously for a couple years. Next trip to the electronics
shop will probably yield a new set just for my piece of mind.  

I was beginning to think my posts were not making it out there until I
saw your reply (Arfa was right about the Virgin Media news server being
troublesome!)

I don't remember looking closely but I don't think they were
particularly domed.  It was at least 2 years ago when it died.  I do
remember that everything looked very clean in there.  The amp had an
easy life in a church install but for some reason the power transformer
got shorted on the primary thus blowing the mains fuse every time.
Since it was a custom part I enquired with Toroid International about
purchasing a replacement but it would have cost about £150 as I guess
they were not making these in volume any more.  When I saw that I could
just replace the whole amp for the same money it was a no-brainer.

One reason I like the 700D is that the cooling system is efficient and the
fan had infinite control. It is as quiet as a mouse until you started to
drive it. It also draws fresh air directly through the front through a
foam cell filter and through a heat sink tunnel and doesn't expose the
entire amp to forced air dust and other contaminates. Mine suffered a fall
while in a rack which broke the A channel banana jack off or I wouldn't
have ever noticed those 4 caps. They're not big enough physically to be
for rail currents so they must serve some other purpose in the driver
stage?? Here is a recent pic of my 700D in the rack that fell over. Lucky
all the other equipment wasn't in the rack when it fell backwards.

http://i273.photobucket.com/albums/jj220/meatplow1/music/CIMG0259.jpg

Below the Crown amp is a rare Sound Code Systems 2350A MOS-FET amp someone
gave me after they couldn't find anyone to repair it back in 1998. It
needed a new set of outputs 2SK134/2SJ49 TO3 case that had been
discontinued and unavailable at the time. I did find a set on the internet
and repaired the amp successfully. It's been used on and off as a source
for 18" subs in a tri-amped band PA setup since then without any problems.
It too is a quiet amp having a similar cooling system to the 700D. It's
heat sink includes a bristled radiator which is unique.- Dölj citerad text -

- Visa citerad text -

Eeyore wrote:
Meat Plow wrote:

Besides, I can buy a 2000 watt amp brand new also made in China for around
$300 US.

I wouldn't expect it to work for very long.

Seems to me that you have a problem with anything made in China.

You might also remember some time ago when I posted for help with a dead
Studiomaster 700D. The fault turned out to be a bad power transformer
which was not economical to replace even by substitution with off the
shelf parts.

Seems to me that you have a problem with anything made in China.
We all know that you get some crap made there but sometimes
some good stuff comes from there.

There is a difference between items made in China and designed in China. I
have plenty of Chinese-manufactured items that are of high quality. I have
many fewer that were _designed_ there. One is an iRiver H120 jukebox, which
is of very high quality.

William Sommerwerck wrote:
Seems to me that you have a problem with anything made in China.
We all know that you get some crap made there but sometimes
some good stuff comes from there.

There is a difference between items made in China and designed in China. I
have plenty of Chinese-manufactured items that are of high quality. I have
many fewer that were _designed_ there. One is an iRiver H120 jukebox, which
is of very high quality.

Isn't iRiver Korean? We did some work with their products a while back,
had a couple of their engineers over here, I'm pretty sure they weren't
Chinese but I could be wrong.

Tim Phipps wrote:
Eeyore wrote:
Meat Plow wrote:

Besides, I can buy a 2000 watt amp brand new also made in China for around
$300 US.

I wouldn't expect it to work for very long.


Seems to me that you have a problem with anything made in China. We all
know that you get some crap made there but sometimes some good stuff
comes from there. Most of my amps are British made (Matrix) but I have
a couple of Chinese made amps, one Audiohead and the other T.amp brand
from thomann.de which look like the same amp to me, both have been in
service on the road for about 3 years now without trouble.

You might also remember some time ago when I posted for help with a dead
Studiomaster 700D. The fault turned out to be a bad power transformer
which was not economical to replace even by substitution with off the
shelf parts. That amp got replaced with another Chinese made T.amp from
Thomann which has also given me no problems.

Do you remember looking at the 4-63 volt, 3300uf caps in your 700D? I just
replaced the banana jack on mine and those 4 caps looked like the tops
were puffed. I pulled the top off one and there is a convexed steel cap

over the actual can under the heat shrink that makes these look domed. And
they appear also to run pretty warm discoloring the white glue used to
bond them to the pcb. The amp works fine otherwise and I've never had any
problems with it. It was formerly used to power A/V sub-woofers and had
been left on continuously for a couple years. Next trip to the electronics
shop will probably yield a new set just for my piece of mind.

One reason I like the 700D is that the cooling system is efficient and the
fan had infinite control. It is as quiet as a mouse until you started to
drive it. It also draws fresh air directly through the front through a
foam cell filter and through a heat sink tunnel and doesn't expose the
entire amp to forced air dust and other contaminates.

Mine suffered a fall while in a rack which broke the A channel banana jack off
or I wouldn't
have ever noticed those 4 caps. They're not big enough physically to be
for rail currents

so they must serve some other purpose in the driver stage??