Crown CE2000....anyone actually repairing this junk?

[Gtr_tech]

Got a CE2000 in that was damaged by running it in the wrong output mode (I think it was set to bridge with stereo spkr cabling, maybe the opposite) and took out a whole bank of output devices. There's SMT stuff blown up all over this thing....all the emitter resistors (1/4w smt....how are they getting away with this??) are open on the bad bank....other smt transistors and resistors....who knows what else. There's really no way to work on them without taking *everything* out of the case and strewing it all over the bench. With the hot heatsink design that's not my idea of fun.

I'm thinking its not worth the hassle. Pass....parts carcas.....

[tim]

When I get stuff like that, I try to find out how much a new board would cost from the manufacturer and then mark it up 50% and tell the customer how much for the repair...usually they pass on it....if they don't and DO want it fixed, it's usually a board swap / an easy fix and you make a few bucks.

Some companies won't sell you a board either because you're not an Authorized repair center or they just don't sell fully populated boards to anyone, regardless of who you are. In that case I just call the customer and let him know it isn't worth fixing.

[Gtr_tech]

Since they're discontinued, I doubt they (Crown) want anything to do with them.

[mac1amps]

Wow! What a change from the old days when Crown was looked upon as "state of the art". So much for progress.

[oc disorder]

Had a CE 1000 ages ago with the fan circuit kaput.Replaced the smd MJD112 but that was all that was wrong.
At the time I saved some coments from a forum that no longer seems to exist. So here from my personal wayback machine...

I see a steady trickle of these things with amps totally FUBAR.
Crown is meant to be a reputable outfit, but often there does not seem to
be any evidence of user abuse, so it kinda points to a design flaw. When
they go bang they REALLY go bang, and often take out the wooffer as
collateral damage. Rebuilding them takes forever, and there's always that
nasty feeling that, not knowing the cause of the original fault, they may
do it again.
Anyone have any idea why they fail ? M
(picture also attached oc)

Ouch !!
It is a bit hard to tell from the Photo but those aren't the Emitter
Resistors are they ???

R wrote in

No they aren't :-) They were before they got vapourised - 2 * 2512 (1
watt) per output device. Tis the only time I've ever seen these tiny
critters used in this application - they don't cope well when the MJ's
head south.
M

M wrote:

The CE1000/2000 series amps are known to be somewhat weak amps,
especially for sub duty. The CE4000 is a different animal and is more
up to the task. It is not the same design as the other two. I would not
recommend smaller model CE series for anything other then higher
frequency applications at higher impedances - no lower then 4 ohms
stereo/8 ohms bridged. Do yourself a favor and get something more heavy
duty for you subs.

R

M said

No they don't!

I have fixed countless CE1000/2000 Sometimes if it's a warranty job you can
talk Crown into a new board. I was also finding many vaproized traces
also... WATCH FOR THESE!!!!!. I always felt bad sending these back out.

Some reasons I found for failure:

NL4 to 1/4 adaptors in bridged mode or wired improperly.

Operator error, it's a low end amp and lower end users tend to be DJ's
running the hell out of them.

It's not a 1000 watt amp, it's 225 a side, and will be damn lucky to do this
for very long. Crown started using a limiting system, when in these
limiters (like all limiters) the average power is raised. They don't seem
to be able to handle the stress.

If something goes south in a die-hard true component amp then it will go
into protect, the smaller components (SMT) tend to go fast and do a good job
at the cascade effect.

Crown has had MANY updates, study these and watch your serial numbers. I had
all the updates printed out above my bench

If the amplifier is run within spec, no clip lights, they will run a long
time. If you run it like it's not yours it's going to cost 'ya.

I never agreed with a 2 watt total SMT emitter resistor, I'm not saying it
won't work on paper but in the real world.......

Best use of SMT in a inexpensive amp I feel is the RMX series, SMT where
it's applicable and thru hole where it's not.

Nice pic! Does the bottom of the case look like someone dragged a welding rod
around it? If not then they didn't do it right

Other reason's for failure I have found:

Renegade screw under board, from another amp in the rack, big holes in front
you know!

Dirt, these baby's will get hot!

Fan failure and fan control failure.

overvoltage 220V in USA, DUH!

They get cranky when powered up and and come out of protect when lots of
signal is applied (breaker trip, protect re-init). I know but it happens!
One ot two oscillated, found grounding torx has come loose.
Good luck, I feel your pain! C

C W wrote:
There is no reason why a protection circuit should not work reliably,
unless its incorrectly designed. I have seen many incorrectly designed
protection circuits though.
It should not do this.
It sounds like there are main design faults. If you can post the
schematic, I could probbaly tell you whats wrong, if I have the time:-)

K A
Read, a limiter run on the ragged edge raises average power. Many of these
users are running them on the ragged edge. Yet another good example of how
being a desk engineer differs from seeing how the real world treats gear.

Should not do what, run reliably if operated within it's specs? SMT
components have a higher speed of heat rise and decline due to their lack of
surface area, to design a protection circuit to deal with SOA of ALL the
semiconductors would bring the amp beyond it's price point. People are just
hitting them too hard, too fast.

Don't need a schematic, flip one over Don't have to be a design engineer
to go, "oh dear god" You probably will not find a fault with your
calculator, Crown has some great engineers, they just missed this one on the
price-reliability-who'sgonnauseit ratio. If you are what you say you are
then you will see the faults immediately if you have real world feild
expierience. C

Yup, they tend to look like my first "Hell I can do that, it looks easy"
adolescent attempts to arc weld rust holes in the mudguards of a Hudson
Terraplane !.

I have a couple of intractibles that are doing this, one on one channel,
one on t'other. Customer cupport has been interesting - Crown have said
go away, not our problem, call JBL (as these particular specimens are out
of 418SPs), JBL simply remain silent.
Thanks for your thoughts, C
M

"M D" said
I have seen that and found a burnt trace going to a "snubbing cap" just
after the pre driver (I think). Can't even remember location since I
stopped working on these a year and a half ago. Rarely I have seen the cap
go bad but it's usually the trace.

The oscillation I was referring to was a flat out "take off and run like
hell" till the protection kicked in. Usually too late for the SMT gain
stage.

Any burns on a JBL VC and it's "no soup for you" VERY strict warranty
policy. I have seen loyal JBL customers turn away from the brand in favor
of a more "Liberal" warranty policy. Been run head-long into that fence a
few times also. Fun to be the middle man eh? BTW I am still a JBL user,
never burnt a coil though

Un-pertaining to the CE series....Think about what a cone goes through
during ODEP limiting, food for thought......"no soup for you".....again.
C

[jrfrond]

That level of damage is almost impossible to repair on a CE2000. The CE1000 and 2000 were all board swaps at that level.

Crown no longer carries the Main PCBA for that amp, but we have two in stock if you want to purchase one. PM or e-mail me.

[Gtr_tech]

Had a CE 1000 ages ago with the fan circuit kaput.Replaced the smd MJD112 but that was all that was wrong.
At the time I saved some coments from a forum that no longer seems to exist. So here from my personal wayback machine...


C[/COLOR]

HAH! The picture says it all.....same thing I have here......<laughing>.....
Whatta buncha crappity crap crap!

[Steve Conner]

Ouch, that looks pretty burnt up.

I think the problem started when Crown brought out a budget range. They needed Chinese crap of their own to compete with the Chinese crap sold by Samson, Tapco, Behringer and so on.

As far as I know the budget amps weren't even designed by Crown, the design was outsourced. However this is just a rumour I heard.

[jrfrond]

Ouch, that looks pretty burnt up.

I think the problem started when Crown brought out a budget range. They needed Chinese crap of their own to compete with the Chinese crap sold by Samson, Tapco, Behringer and so on.

As far as I know the budget amps weren't even designed by Crown, the design was outsourced. However this is just a rumour I heard.

Actually, the CE1000 and 2000 (same topology; the 2K uses higher supply rails and more devices for higher wattage) are pretty much an updated version of the old, reliable DC300A design, and ARE Crown-designed. Crown designs ALL of their own power amps, including the new xTi-series which replaces the CE1K/2K-series, which originally replaced the PowerBase series. The difference with all of the new stuff is that surface-mount technology makes it more economical to board-swap than troubleshoot.