[Nate Najar]

K&H 0110 powered near fields. They're both giving a constant, low level high pitched whine and one of them has diminished high frequency response so the image is shifting. I checked with neumann about service and of course they're long out of warranty. I am in Florida. I imagine the only real option for repair is to indeed ship them up to neumann in Ct and pay the rate, but does anyone know of any other appropriately capable and possibly more convenient options for servicing these?

thanks!

N

[Nate Najar]

On Wednesday, December 14, 2016 at 10:40:50 AM UTC-5, Nate Najar wrote:
K&H 0110 powered near fields. They're both giving a constant, low level high pitched whine and one of them has diminished high frequency response so the image is shifting. I checked with neumann about service and of course they're long out of warranty. I am in Florida. I imagine the only real option for repair is to indeed ship them up to neumann in Ct and pay the rate, but does anyone know of any other appropriately capable and possibly more convenient options for servicing these?

thanks!

N

$700(!) from neumann for repair. I can buy a good condition second hand set of these speakers for $1000!

[John Williamson]

On 14/12/2016 15:46, Nate Najar wrote:
On Wednesday, December 14, 2016 at 10:40:50 AM UTC-5, Nate Najar wrote:
K&H 0110 powered near fields. They're both giving a constant, low level high pitched whine and one of them has diminished high frequency response so the image is shifting. I checked with neumann about service and of course they're long out of warranty. I am in Florida. I imagine the only real option for repair is to indeed ship them up to neumann in Ct and pay the rate, but does anyone know of any other appropriately capable and possibly more convenient options for servicing these?

thanks!

N

$700(!) from neumann for repair. I can buy a good condition second hand set of these speakers for $1000!

Send them to Neumann, and you can be sure they'll be repaired to
original spec and should last as long as they have from new.

Second hand speakers will be a crap shoot, and you'll be wondering why
the original owner wanted to get rid of them.

--
Tciao for Now!

John.

[JackA]

On Wednesday, December 14, 2016 at 10:40:50 AM UTC-5, Nate Najar wrote:
K&H 0110 powered near fields. They're both giving a constant, low level high pitched whine and one of them has diminished high frequency response so the image is shifting. I checked with neumann about service and of course they're long out of warranty. I am in Florida. I imagine the only real option for repair is to indeed ship them up to neumann in Ct and pay the rate, but does anyone know of any other appropriately capable and possibly more convenient options for servicing these?

thanks!

N

Obsolete. Get the K+H 120's, cheaper and better audio quality! Found that on Gearslutz!

Jack

[Scott Dorsey]

Nate Najar wrote:
On Wednesday, December 14, 2016 at 10:40:50 AM UTC-5, Nate Najar wrote:
K&H 0110 powered near fields. They're both giving a constant, low level =
high pitched whine and one of them has diminished high frequency response s=
o the image is shifting. I checked with neumann about service and of cours=
e they're long out of warranty. I am in Florida. I imagine the only real =
option for repair is to indeed ship them up to neumann in Ct and pay the ra=
te, but does anyone know of any other appropriately capable and possibly mo=
re convenient options for servicing these?

$700(!) from neumann for repair. I can buy a good condition second hand se=
t of these speakers for $1000!

Before doing anything, I'd try taking them out of service and putting them
into a different room and see if they still whine all alone with nothing
connected up to them. If not, you may have a grounding issue and not a
speaker issue.

Also I'd swap the two speakers left and right and see if the high frequency
problem is actually the speakers and not the room.

These are likely to be two unrelated issues. The whine is likely to be
something easy for a good technician to fix; bad supply capacitors or a
loose ground connection somewhere. If the high frequencies are altered on
one, though, that may be a more difficult thing to track down.

Ask Neumann if they will do repair as time and materials instead of as flat
rate. That's likely to be less expensive (although can sometimes be more).
Sadly Neumann's service is not what it once was when they were a more
engineering-driven company.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Nate Najar]

On Wednesday, December 14, 2016 at 12:39:12 PM UTC-5, Scott Dorsey wrote:

Before doing anything, I'd try taking them out of service and putting them
into a different room and see if they still whine all alone with nothing
connected up to them. If not, you may have a grounding issue and not a
speaker issue.

I did try that



Also I'd swap the two speakers left and right and see if the high frequency
problem is actually the speakers and not the room.

this too



These are likely to be two unrelated issues. The whine is likely to be
something easy for a good technician to fix; bad supply capacitors or a
loose ground connection somewhere. If the high frequencies are altered on
one, though, that may be a more difficult thing to track down.


they are unrelated... the one with the diminished HF response was doing the high pitched whine thing for a while- but only when it was powered up. after a few minutes it would go away. the other one (with the seemingly still correct freq response) just started whining the other day and it is a different pitch and louder than the other. And they both do it constantly now..

Ask Neumann if they will do repair as time and materials instead of as flat
rate. That's likely to be less expensive (although can sometimes be more).
Sadly Neumann's service is not what it once was when they were a more
engineering-driven company.

the problem is that their system is completely automated now. They even disconnected the phone number! I cannot figure out how to reach a real person and I've spent a good deal of time this morning trying to find that information.

[geoff]

On 15/12/2016 4:40 a.m., Nate Najar wrote:
K&H 0110 powered near fields. They're both giving a constant, low level high pitched whine and one of them has diminished high frequency response so the image is shifting. I checked with neumann about service and of course they're long out of warranty. I am in Florida. I imagine the only real option for repair is to indeed ship them up to neumann in Ct and pay the rate, but does anyone know of any other appropriately capable and possibly more convenient options for servicing these?

thanks!

N


Surely there is a local electronic service outfit capable of
fault-finding what is likely to be a basic problem ?

But two failed at the same time ? Maybe check out some possible external
factor firs.

geoff

[geoff]

On 15/12/2016 10:12 a.m., geoff wrote:
On 15/12/2016 4:40 a.m., Nate Najar wrote:
K&H 0110 powered near fields. They're both giving a constant, low
level high pitched whine and one of them has diminished high
frequency response so the image is shifting. I checked with neumann
about service and of course they're long out of warranty. I am in
Florida. I imagine the only real option for repair is to indeed ship
them up to neumann in Ct and pay the rate, but does anyone know of
any other appropriately capable and possibly more convenient options
for servicing these?

thanks!

N


Surely there is a local electronic service outfit capable of
fault-finding what is likely to be a basic problem ?

But two failed at the same time ? Maybe check out some possible
external factor firs.

geoff


....t

geoff

[Nate Najar]

On Wednesday, December 14, 2016 at 4:12:45 PM UTC-5, geoff wrote:

Surely there is a local electronic service outfit capable of
fault-finding what is likely to be a basic problem ?


if there is such an outfit, I haven't found one. There


But two failed at the same time ? Maybe check out some possible external
factor firs.

well, the one developed the whine a long time ago. the other developed a similar but not exactly the same whine very recently. and the HF thing is almost nearly a driver issue and is also fairly new. I've eliminated every external factor I can think of.....

[JackA]

On Wednesday, December 14, 2016 at 4:12:45 PM UTC-5, geoff wrote:
On 15/12/2016 4:40 a.m., Nate Najar wrote:
K&H 0110 powered near fields. They're both giving a constant, low level high pitched whine and one of them has diminished high frequency response so the image is shifting. I checked with neumann about service and of course they're long out of warranty. I am in Florida. I imagine the only real option for repair is to indeed ship them up to neumann in Ct and pay the rate, but does anyone know of any other appropriately capable and possibly more convenient options for servicing these?

thanks!

N


Surely there is a local electronic service outfit capable of
fault-finding what is likely to be a basic problem ?

But two failed at the same time ? Maybe check out some possible external
factor firs.

I'm with you, highly unusual for both to act up. Found the manual, looks like a bass reflex speaker with amp built-in (probably for a flatter response). If both have identical amps, start comparing voltages. There's more to this story.

Jack


geoff

[Trevor]

On 15/12/2016 2:46 AM, Nate Najar wrote:
On Wednesday, December 14, 2016 at 10:40:50 AM UTC-5, Nate Najar
wrote:
K&H 0110 powered near fields. They're both giving a constant, low
level high pitched whine and one of them has diminished high
frequency response so the image is shifting. I checked with
neumann about service and of course they're long out of warranty.
I am in Florida. I imagine the only real option for repair is to
indeed ship them up to neumann in Ct and pay the rate,

Why would you imagine that?

but does anyone know of any other appropriately capable and possibly
more convenient options for servicing these?

thanks!

$700(!) from neumann for repair. I can buy a good condition second
hand set of these speakers for $1000!

That makes your decision easy then, get a local tech to look at them
first. Sounds like an amplifier issue, which should be a lot cheaper to
fix than the drivers themselves. And cheaper than buying used ones which
may have problems anyway.

Trevor.

[geoff]

On 15/12/2016 10:43 a.m., Nate Najar wrote:
On Wednesday, December 14, 2016 at 4:12:45 PM UTC-5, geoff wrote:
Surely there is a local electronic service outfit capable of
fault-finding what is likely to be a basic problem ?

if there is such an outfit, I haven't found one. There


But two failed at the same time ? Maybe check out some possible external
factor firs.
well, the one developed the whine a long time ago. the other developed a similar but not exactly the same whine very recently. and the HF thing is almost nearly a driver issue and is also fairly new. I've eliminated every external factor I can think of.....


OK not at same time. then.

Possibly aging capacitors, maybe in power supply section. If so likely
obvious to any service-tech worth his/her salt. Pro-audio, hi-fi, TV, etc

geoff

[John Williamson]

On 15/12/2016 03:37, geoff wrote:
On 15/12/2016 10:43 a.m., Nate Najar wrote:

Possibly aging capacitors, maybe in power supply section. If so likely
obvious to any service-tech worth his/her salt. Pro-audio, hi-fi, TV, etc


Mode = cynic That's if you can find one locally that knows which end
of a soldering iron to hold.

--
Tciao for Now!

John.

[Nate Najar]

On Thursday, December 15, 2016 at 9:12:47 AM UTC-5, John Williamson wrote:


Mode = cynic That's if you can find one locally that knows which end
of a soldering iron to hold.


my point exactly!

[Scott Dorsey]

geoff wrote:

Possibly aging capacitors, maybe in power supply section. If so likely
obvious to any service-tech worth his/her salt. Pro-audio, hi-fi, TV, etc

Yeah, that's my suspicion, and that's kind of shameful for a piece of
equipment at this price range.

Another possibility (and an even more shameful one) is that an audio stage
is oscillating because of an aging electrolytic.

Also the ever popular loose or corroded ground to a shield.

And... if there is a lot of ultrasonic crap coming out as well, that may have
affected the tweeter....
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[John Williamson]

On 15/12/2016 15:13, Scott Dorsey wrote:
geoff wrote:

Possibly aging capacitors, maybe in power supply section. If so likely
obvious to any service-tech worth his/her salt. Pro-audio, hi-fi, TV, etc

Yeah, that's my suspicion, and that's kind of shameful for a piece of
equipment at this price range.

Are they of an age to have been caught in the Chinese capacitor problem?
A lot of makers got caught by that, even high end component suppliers
suffered from that.


--
Tciao for Now!

John.

[JackA]

On Wednesday, December 14, 2016 at 10:37:08 PM UTC-5, geoff wrote:
On 15/12/2016 10:43 a.m., Nate Najar wrote:
On Wednesday, December 14, 2016 at 4:12:45 PM UTC-5, geoff wrote:
Surely there is a local electronic service outfit capable of
fault-finding what is likely to be a basic problem ?

if there is such an outfit, I haven't found one. There


But two failed at the same time ? Maybe check out some possible external
factor firs.
well, the one developed the whine a long time ago. the other developed a similar but not exactly the same whine very recently. and the HF thing is almost nearly a driver issue and is also fairly new. I've eliminated every external factor I can think of.....


OK not at same time. then.

Possibly aging capacitors, maybe in power supply section. If so likely
obvious to any service-tech worth his/her salt. Pro-audio, hi-fi, TV, etc

geoff

Maybe this is like Remastering phobia, where one person mentions capacitor aging, then the entire world does! Been involved with electronic most of my life, never really had issues with capacitors.

If there is feedback, I'd look at the loop that controls input signal to avoid output noise.

Jack

[Scott Dorsey]

John Williamson wrote:
On 15/12/2016 15:13, Scott Dorsey wrote:
geoff wrote:

Possibly aging capacitors, maybe in power supply section. If so likely
obvious to any service-tech worth his/her salt. Pro-audio, hi-fi, TV, etc

Yeah, that's my suspicion, and that's kind of shameful for a piece of
equipment at this price range.

Are they of an age to have been caught in the Chinese capacitor problem?
A lot of makers got caught by that, even high end component suppliers
suffered from that.

And THAT was even more shameful. But easy enough to diagnose.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Nil[_2_]]

On 15 Dec 2016, JackA wrote in
rec.audio.pro:

Maybe this is like Remastering phobia, where one person mentions
capacitor aging, then the entire world does! Been involved with
electronic most of my life, never really had issues with
capacitors.

Selling batteries at Radio Shack doesn't count.

The fact that you're completely ignorant of the capacitor issue says
all that needs to be said about your "involvement".

[JackA]

On Thursday, December 15, 2016 at 2:00:15 PM UTC-5, Nil wrote:
On 15 Dec 2016, JackA wrote in
rec.audio.pro:

Maybe this is like Remastering phobia, where one person mentions
capacitor aging, then the entire world does! Been involved with
electronic most of my life, never really had issues with
capacitors.

Selling batteries at Radio Shack doesn't count.

The fact that you're completely ignorant of the capacitor issue says
all that needs to be said about your "involvement".

Hello Nil!

Jack

[Trevor]

On 16/12/2016 1:12 AM, John Williamson wrote:
On 15/12/2016 03:37, geoff wrote:
On 15/12/2016 10:43 a.m., Nate Najar wrote:

Possibly aging capacitors, maybe in power supply section. If so likely
obvious to any service-tech worth his/her salt. Pro-audio, hi-fi, TV, etc


Mode = cynic That's if you can find one locally that knows which end
of a soldering iron to hold.

You mean you don't then? And don't know how to look for one either?

Trevor.

[Trevor]

On 16/12/2016 1:40 AM, Nate Najar wrote:
On Thursday, December 15, 2016 at 9:12:47 AM UTC-5, John Williamson wrote:

Mode = cynic That's if you can find one locally that knows which end
of a soldering iron to hold.


my point exactly!


Gee, somebody who can't do it themselves, and doesn't even know how to
look for somebody who can, shouldn't be chucking **** on others IMO.
Asking here for recommendations is fine, why not leave it at that?

Trevor.

[Trevor]

On 16/12/2016 2:39 AM, John Williamson wrote:
On 15/12/2016 15:13, Scott Dorsey wrote:
geoff wrote:

Possibly aging capacitors, maybe in power supply section. If so likely
obvious to any service-tech worth his/her salt. Pro-audio, hi-fi, TV,
etc

Yeah, that's my suspicion, and that's kind of shameful for a piece of
equipment at this price range.

Are they of an age to have been caught in the Chinese capacitor problem?
A lot of makers got caught by that, even high end component suppliers
suffered from that.

Which is the shameful part. Real high end manufacturers only use high
quality components sourced from reliable suppliers, NOT the cheap
Chinese knock offs that caused all the problems.

Trevor.

[John Williamson]

On 16/12/2016 03:45, Trevor wrote:
On 16/12/2016 1:12 AM, John Williamson wrote:
On 15/12/2016 03:37, geoff wrote:
On 15/12/2016 10:43 a.m., Nate Najar wrote:

Possibly aging capacitors, maybe in power supply section. If so likely
obvious to any service-tech worth his/her salt. Pro-audio, hi-fi, TV,
etc


Mode = cynic That's if you can find one locally that knows which end
of a soldering iron to hold.

You mean you don't then? And don't know how to look for one either?

I'd have no trouble repairing them, but the transatlantic shipping bith
ways might make it not worth the bother. I've been repairing and
building stuff for decades.

I don't know about your side of the herring pond, but on this side,
competent repair techs are getting very rare.
--
Tciao for Now!

John.

[John Williamson]

On 16/12/2016 03:52, Trevor wrote:
On 16/12/2016 2:39 AM, John Williamson wrote:
Are they of an age to have been caught in the Chinese capacitor problem?
A lot of makers got caught by that, even high end component suppliers
suffered from that.

Which is the shameful part. Real high end manufacturers only use high
quality components sourced from reliable suppliers, NOT the cheap
Chinese knock offs that caused all the problems.

A lot of them made it into places you'd not expect to see them. They
tested perfect when they were installed, it was only a couple of years
down the line the problems became apparent.


--
Tciao for Now!

John.

[Scott Dorsey]

In article , Trevor wrote:
On 16/12/2016 2:39 AM, John Williamson wrote:
On 15/12/2016 15:13, Scott Dorsey wrote:
geoff wrote:

Possibly aging capacitors, maybe in power supply section. If so likely
obvious to any service-tech worth his/her salt. Pro-audio, hi-fi, TV,
etc

Yeah, that's my suspicion, and that's kind of shameful for a piece of
equipment at this price range.

Are they of an age to have been caught in the Chinese capacitor problem?
A lot of makers got caught by that, even high end component suppliers
suffered from that.

Which is the shameful part. Real high end manufacturers only use high
quality components sourced from reliable suppliers, NOT the cheap
Chinese knock offs that caused all the problems.

Well, in fact in this case it was cheap Taiwanese knockoffs, really, although
the issue of (frequently invalid) technology leaks in China is a serious one.

But it's true that you didn't see Panasonic or Rifa putting out products with
the "improved" electrolyte....

The difference in price is substantial, though. I can get Teapo caps for as
much as an order of magnitude less money than the Panasonic FC types. I can
understand why that is tempting for manufacturers.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[JackA]

On Thursday, December 15, 2016 at 10:52:38 PM UTC-5, Trevor wrote:
On 16/12/2016 2:39 AM, John Williamson wrote:
On 15/12/2016 15:13, Scott Dorsey wrote:
geoff wrote:

Possibly aging capacitors, maybe in power supply section. If so likely
obvious to any service-tech worth his/her salt. Pro-audio, hi-fi, TV,
etc

Yeah, that's my suspicion, and that's kind of shameful for a piece of
equipment at this price range.

Are they of an age to have been caught in the Chinese capacitor problem?
A lot of makers got caught by that, even high end component suppliers
suffered from that.

Which is the shameful part. Real high end manufacturers only use high
quality components sourced from reliable suppliers, NOT the cheap
Chinese knock offs that caused all the problems.

Trevor.

I'd like to interject here. I purchased a Shortwave radio, Tecsun brand, Made In China, at it received LOTS of review applause; I was impressed, too.

Look at America now, toss some recycled foam in a cloth bag, claim it has interlocking foam pieces, fabricate some idiotic Patent, sell it as My Pillow US Made crap for $100.

Jack

[[email protected]]

the title of the thread would sound better as

meine klein und hummel

:-)

m

[Chuck[_12_]]

On Thu, 15 Dec 2016 08:18:05 -0800 (PST), JackA
wrote:

On Wednesday, December 14, 2016 at 10:37:08 PM UTC-5, geoff wrote:
On 15/12/2016 10:43 a.m., Nate Najar wrote:
On Wednesday, December 14, 2016 at 4:12:45 PM UTC-5, geoff wrote:
Surely there is a local electronic service outfit capable of
fault-finding what is likely to be a basic problem ?

if there is such an outfit, I haven't found one. There


But two failed at the same time ? Maybe check out some possible external
factor firs.
well, the one developed the whine a long time ago. the other developed a similar but not exactly the same whine very recently. and the HF thing is almost nearly a driver issue and is also fairly new. I've eliminated every external factor I can think of.....


OK not at same time. then.

Possibly aging capacitors, maybe in power supply section. If so likely
obvious to any service-tech worth his/her salt. Pro-audio, hi-fi, TV, etc

geoff

Maybe this is like Remastering phobia, where one person mentions capacitor aging, then the entire world does! Been involved with electronic most of my life, never really had issues with capacitors.

If there is feedback, I'd look at the loop that controls input signal to avoid output noise.

Jack

Of the electronic items that I have repaired for the last 20 years,
electrolytic capacitor problems have been the most common failure.

---
This email has been checked for viruses by Avast antivirus software.
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[JackA]

On Friday, December 16, 2016 at 4:58:40 PM UTC-5, Chuck wrote:
On Thu, 15 Dec 2016 08:18:05 -0800 (PST), JackA
wrote:

On Wednesday, December 14, 2016 at 10:37:08 PM UTC-5, geoff wrote:
On 15/12/2016 10:43 a.m., Nate Najar wrote:
On Wednesday, December 14, 2016 at 4:12:45 PM UTC-5, geoff wrote:
Surely there is a local electronic service outfit capable of
fault-finding what is likely to be a basic problem ?

if there is such an outfit, I haven't found one. There


But two failed at the same time ? Maybe check out some possible external
factor firs.
well, the one developed the whine a long time ago. the other developed a similar but not exactly the same whine very recently. and the HF thing is almost nearly a driver issue and is also fairly new. I've eliminated every external factor I can think of.....


OK not at same time. then.

Possibly aging capacitors, maybe in power supply section. If so likely
obvious to any service-tech worth his/her salt. Pro-audio, hi-fi, TV, etc

geoff

Maybe this is like Remastering phobia, where one person mentions capacitor aging, then the entire world does! Been involved with electronic most of my life, never really had issues with capacitors.

If there is feedback, I'd look at the loop that controls input signal to avoid output noise.

Jack

Of the electronic items that I have repaired for the last 20 years,
electrolytic capacitor problems have been the most common failure.

Interesting. If I had to pick a common component, it would be semiconductor failure.

Jack



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[Chuck[_12_]]

On Fri, 16 Dec 2016 07:48:51 +0000, John Williamson
wrote:

On 16/12/2016 03:52, Trevor wrote:
On 16/12/2016 2:39 AM, John Williamson wrote:
Are they of an age to have been caught in the Chinese capacitor problem?
A lot of makers got caught by that, even high end component suppliers
suffered from that.

Which is the shameful part. Real high end manufacturers only use high
quality components sourced from reliable suppliers, NOT the cheap
Chinese knock offs that caused all the problems.

A lot of them made it into places you'd not expect to see them. They
tested perfect when they were installed, it was only a couple of years
down the line the problems became apparent.


Rubycom and Elna electrolytic capacitors had a high failure rate for
years and they are considered good brands.

---
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https://www.avast.com/antivirus

[JackA]

On Friday, December 16, 2016 at 5:31:56 PM UTC-5, Chuck wrote:
On Fri, 16 Dec 2016 07:48:51 +0000, John Williamson
wrote:

On 16/12/2016 03:52, Trevor wrote:
On 16/12/2016 2:39 AM, John Williamson wrote:
Are they of an age to have been caught in the Chinese capacitor problem?
A lot of makers got caught by that, even high end component suppliers
suffered from that.

Which is the shameful part. Real high end manufacturers only use high
quality components sourced from reliable suppliers, NOT the cheap
Chinese knock offs that caused all the problems.

A lot of them made it into places you'd not expect to see them. They
tested perfect when they were installed, it was only a couple of years
down the line the problems became apparent.


Rubycom and Elna electrolytic capacitors had a high failure rate for
years and they are considered good brands.

What type electronic equipment are you talking about, Chuck?

Jack



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[Gray_Wolf]

On 12/16/2016 3:58 PM, Chuck wrote:
On Thu, 15 Dec 2016 08:18:05 -0800 (PST), JackA
wrote:

On Wednesday, December 14, 2016 at 10:37:08 PM UTC-5, geoff wrote:
On 15/12/2016 10:43 a.m., Nate Najar wrote:
On Wednesday, December 14, 2016 at 4:12:45 PM UTC-5, geoff wrote:
Surely there is a local electronic service outfit capable of
fault-finding what is likely to be a basic problem ?

if there is such an outfit, I haven't found one. There


But two failed at the same time ? Maybe check out some possible external
factor firs.
well, the one developed the whine a long time ago. the other developed a similar but not exactly the same whine very recently. and the HF thing is almost nearly a driver issue and is also fairly new. I've eliminated every external factor I can think of.....


OK not at same time. then.

Possibly aging capacitors, maybe in power supply section. If so likely
obvious to any service-tech worth his/her salt. Pro-audio, hi-fi, TV, etc

geoff

Maybe this is like Remastering phobia, where one person mentions capacitor aging, then the entire world does! Been involved with electronic most of my life, never really had issues with capacitors.

If there is feedback, I'd look at the loop that controls input signal to avoid output noise.

Jack

Of the electronic items that I have repaired for the last 20 years,
electrolytic capacitor problems have been the most common failure.


Mine too and I've been in the trade for 50+ years. I've replaced a ton
of the old wax paper caps with some good mylar also.

[Trevor]

On 17/12/2016 8:58 AM, Chuck wrote:
On Thu, 15 Dec 2016 08:18:05 -0800 (PST), JackA
wrote:
On Wednesday, December 14, 2016 at 10:37:08 PM UTC-5, geoff wrote:
Possibly aging capacitors, maybe in power supply section. If so
likely obvious to any service-tech worth his/her salt. Pro-audio,
hi-fi, TV, etc

Maybe this is like Remastering phobia, where one person mentions
capacitor aging, then the entire world does! Been involved with
electronic most of my life, never really had issues with
capacitors.

Of the electronic items that I have repaired for the last 20 years,
electrolytic capacitor problems have been the most common failure.

Yep, but since Jackass has never repaired anything, he thinks it's a myth.

Trevor.

[Trevor]

On 16/12/2016 6:48 PM, John Williamson wrote:
On 16/12/2016 03:52, Trevor wrote:
On 16/12/2016 2:39 AM, John Williamson wrote:
Are they of an age to have been caught in the Chinese capacitor problem?
A lot of makers got caught by that, even high end component suppliers
suffered from that.

Which is the shameful part. Real high end manufacturers only use high
quality components sourced from reliable suppliers, NOT the cheap
Chinese knock offs that caused all the problems.

A lot of them made it into places you'd not expect to see them. They
tested perfect when they were installed, it was only a couple of years
down the line the problems became apparent.

Well duh! That is usual for most inferior components, which is why no
self respecting high end manufacturer would ever take the risk. The
pretend ones only in it to separate suckers from their money (probably
the majority unfortunately) do of course. :-(

Trevor.

[Trevor]

On 17/12/2016 1:01 AM, Scott Dorsey wrote:
In article , Trevor wrote:
On 16/12/2016 2:39 AM, John Williamson wrote:
On 15/12/2016 15:13, Scott Dorsey wrote:
geoff wrote:

Possibly aging capacitors, maybe in power supply section. If so likely
obvious to any service-tech worth his/her salt. Pro-audio, hi-fi, TV,
etc

Yeah, that's my suspicion, and that's kind of shameful for a piece of
equipment at this price range.

Are they of an age to have been caught in the Chinese capacitor problem?
A lot of makers got caught by that, even high end component suppliers
suffered from that.

Which is the shameful part. Real high end manufacturers only use high
quality components sourced from reliable suppliers, NOT the cheap
Chinese knock offs that caused all the problems.

Well, in fact in this case it was cheap Taiwanese knockoffs, really, although
the issue of (frequently invalid) technology leaks in China is a serious one.

But it's true that you didn't see Panasonic or Rifa putting out products with
the "improved" electrolyte....

The difference in price is substantial, though. I can get Teapo caps for as
much as an order of magnitude less money than the Panasonic FC types. I can
understand why that is tempting for manufacturers.

Of course it was tempting for any company working to a price point. That
any manufacturer claiming to be high end and charging whatever the
market will bear would be tempted at the cost of their repuation is the
shameful part. Sadly common when bean counters get control unfortunately.

Trevor.

[Don Pearce[_3_]]

On Fri, 16 Dec 2016 16:31:51 -0600, Chuck wrote:

On Fri, 16 Dec 2016 07:48:51 +0000, John Williamson
wrote:

On 16/12/2016 03:52, Trevor wrote:
On 16/12/2016 2:39 AM, John Williamson wrote:
Are they of an age to have been caught in the Chinese capacitor problem?
A lot of makers got caught by that, even high end component suppliers
suffered from that.

Which is the shameful part. Real high end manufacturers only use high
quality components sourced from reliable suppliers, NOT the cheap
Chinese knock offs that caused all the problems.

A lot of them made it into places you'd not expect to see them. They
tested perfect when they were installed, it was only a couple of years
down the line the problems became apparent.


Rubycom and Elna electrolytic capacitors had a high failure rate for
years and they are considered good brands.

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I did a lot of work last year on switched-mode power supplies for
high reliability applications. The two manufacturers that came out at
the top of the list were Panasonic and Nichicon. Choose 125C
temperature rating and be attentive to ripple current. Also try not to
use the top ten percent of the voltage rating.

After that keep them as cool as possible, and you have a reliable,
long lasting setup.

d

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[John Williamson]

On 17/12/2016 10:31, Don Pearce wrote:
I did a lot of work last year on switched-mode power supplies for
high reliability applications. The two manufacturers that came out at
the top of the list were Panasonic and Nichicon. Choose 125C
temperature rating and be attentive to ripple current. Also try not to
use the top ten percent of the voltage rating.

After that keep them as cool as possible, and you have a reliable,
long lasting setup.

All true, but it conflicts with the desire of makers and users to fit
the PSU into as small a space as possible. In my powered speakers, for
instance, there is minimal heat sinking and it's inside an unvented box
with the PA and the speakers, so keeping it cool is hard. In my portable
mixer, there is a size restriction on the power supply due to it having
to fit in a plug top, and so on...


--
Tciao for Now!

John.

[Don Pearce[_3_]]

On Sat, 17 Dec 2016 11:17:37 +0000, John Williamson
wrote:

On 17/12/2016 10:31, Don Pearce wrote:
I did a lot of work last year on switched-mode power supplies for
high reliability applications. The two manufacturers that came out at
the top of the list were Panasonic and Nichicon. Choose 125C
temperature rating and be attentive to ripple current. Also try not to
use the top ten percent of the voltage rating.

After that keep them as cool as possible, and you have a reliable,
long lasting setup.

All true, but it conflicts with the desire of makers and users to fit
the PSU into as small a space as possible. In my powered speakers, for
instance, there is minimal heat sinking and it's inside an unvented box
with the PA and the speakers, so keeping it cool is hard. In my portable
mixer, there is a size restriction on the power supply due to it having
to fit in a plug top, and so on...

I know, and it is such a shame that cost has to be such an enemy to
quality. My spec was a minimum 7 years guaranteed lifetime and an
operating temperature range from -40 to +85C.

I have several pieces of domestic electronics that I opened on day one
and swapped the main bulk cap (the one that is a reservoir for the
rectified mains) as that is the most stressed one. In a few instances
I had to mount it a couple of inches away on leads.

d

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[Les Cargill[_4_]]

Don Pearce wrote:
On Sat, 17 Dec 2016 11:17:37 +0000, John Williamson
wrote:

On 17/12/2016 10:31, Don Pearce wrote:
I did a lot of work last year on switched-mode power supplies for
high reliability applications. The two manufacturers that came out at
the top of the list were Panasonic and Nichicon. Choose 125C
temperature rating and be attentive to ripple current. Also try not to
use the top ten percent of the voltage rating.

After that keep them as cool as possible, and you have a reliable,
long lasting setup.

All true, but it conflicts with the desire of makers and users to fit
the PSU into as small a space as possible. In my powered speakers, for
instance, there is minimal heat sinking and it's inside an unvented box
with the PA and the speakers, so keeping it cool is hard. In my portable
mixer, there is a size restriction on the power supply due to it having
to fit in a plug top, and so on...

I know, and it is such a shame that cost has to be such an enemy to
quality.

But it isn't. It's more that much of the retail channel is about
overwhelming People With Credit Cards into an impulse purchase.

Example: Main singer has a "floorbox" for his mic ( and acoustic
guitar ). Secondary singer wants to signal seriousness about singing;
buys one. Both will require considerable effort to improve over
nothing in a gain-before-feedback environment.

My spec was a minimum 7 years guaranteed lifetime and an
operating temperature range from -40 to +85C.

I have several pieces of domestic electronics that I opened on day one
and swapped the main bulk cap (the one that is a reservoir for the
rectified mains) as that is the most stressed one. In a few instances
I had to mount it a couple of inches away on leads.


Most of this stuff is designed to sit in a closet for most of its life.

d

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--
Les Cargill