Yamaha Stagepas 300 failure mode

Just as well I'm not paying Yamaha 50 squid a pop for these blown amps.
Repaired one end of 2011 , it bounced back.
It is due to the short stub lead between amp and its immediate speaker, the
elbow connectors.
No name elbows on lead marked UPOFC Classic Pro Loudspeaker Cable. Took a
bit of grinding to cut the top off the elbow, quite thick monkey metal. The
ground connection out to the cable solder point is like a solder tag but
with a 2mm x 1mm x tag thickness lug opposite the solder extension ,that
locates into the moulded plastic insulator. The tag is not spot
welded/bolted to the elbow metal so any twisting of the cable is transfered
to the tag and the ring part can twist and touch the conductor stem to the
tip, as the cylinder insulation along this stem does not extend into this
solder tag, or perhaps as only touching ground contact, then localised
heating and the cylinder insulation melting back a bit. I've not explored
that far in, the top moulded insulation plastic does not look melted.
These elbows have a vague brassy/coppery tinge of plating or something just
on the tips , the main elbow body is Hex in plan and between it and the stem
is what looks like a hank bush swage-form.



Several people have reported that their problems began when they started

On 31/01/2012 11:05, N_Cook wrote:
Just as well I'm not paying Yamaha 50 squid a pop for these blown amps.
Repaired one end of 2011 , it bounced back.
It is due to the short stub lead between amp and its immediate speaker,
the
elbow connectors.
No name elbows on lead marked UPOFC Classic Pro Loudspeaker Cable. Took a
bit of grinding to cut the top off the elbow, quite thick monkey metal.
The
ground connection out to the cable solder point is like a solder tag but
with a 2mm x 1mm x tag thickness lug opposite the solder extension ,that
locates into the moulded plastic insulator. The tag is not spot
welded/bolted to the elbow metal so any twisting of the cable is
transfered
to the tag and the ring part can twist and touch the conductor stem to
the
tip, as the cylinder insulation along this stem does not extend into this
solder tag, or perhaps as only touching ground contact, then localised
heating and the cylinder insulation melting back a bit. I've not explored
that far in, the top moulded insulation plastic does not look melted.
These elbows have a vague brassy/coppery tinge of plating or something
just
on the tips , the main elbow body is Hex in plan and between it and the
stem
is what looks like a hank bush swage-form.



Several people have reported that their problems began when they started
using speaker cables other than those supplied with the units which sadly
are just not quite long enough.

Ron

"Ron" <ron_at_lunevalleyaudio.com> wrote in message
news:qdadnY1LK8NCTrrSnZ2dnUVZ8rOdnZ2d_at_bt.com...
On 31/01/2012 11:05, N_Cook wrote:
Just as well I'm not paying Yamaha 50 squid a pop for these blown amps.
Repaired one end of 2011 , it bounced back.
It is due to the short stub lead between amp and its immediate speaker,
the
elbow connectors.
No name elbows on lead marked UPOFC Classic Pro Loudspeaker Cable. Took
a
bit of grinding to cut the top off the elbow, quite thick monkey metal.
The
ground connection out to the cable solder point is like a solder tag
but
with a 2mm x 1mm x tag thickness lug opposite the solder extension
,that
locates into the moulded plastic insulator. The tag is not spot
welded/bolted to the elbow metal so any twisting of the cable is
transfered
to the tag and the ring part can twist and touch the conductor stem to
the
tip, as the cylinder insulation along this stem does not extend into
this
solder tag, or perhaps as only touching ground contact, then localised
heating and the cylinder insulation melting back a bit. I've not
explored
that far in, the top moulded insulation plastic does not look melted.
These elbows have a vague brassy/coppery tinge of plating or something
just
on the tips , the main elbow body is Hex in plan and between it and the
stem
is what looks like a hank bush swage-form.



Several people have reported that their problems began when they started
using speaker cables other than those supplied with the units which
sadly
are just not quite long enough.

Ron


The thing is, Yamahas user manual specifically warns against using speaker
cables other than those supplied with the units, so they are covered.

e.g.

11 Only use attachments/accessories specified by the manufacturer.

and:

To avoid any possible malfunction, use only the speaker cables included
with
the device




Cheers,


Gareth.

"Ron" <ron_at_lunevalleyaudio.com> wrote in message
news:qdadnY1LK8NCTrrSnZ2dnUVZ8rOdnZ2d_at_bt.com...
On 31/01/2012 11:05, N_Cook wrote:
Just as well I'm not paying Yamaha 50 squid a pop for these blown amps.
Repaired one end of 2011 , it bounced back.
It is due to the short stub lead between amp and its immediate speaker,
the
elbow connectors.
No name elbows on lead marked UPOFC Classic Pro Loudspeaker Cable. Took
a
bit of grinding to cut the top off the elbow, quite thick monkey metal.
The
ground connection out to the cable solder point is like a solder tag
but
with a 2mm x 1mm x tag thickness lug opposite the solder extension
,that
locates into the moulded plastic insulator. The tag is not spot
welded/bolted to the elbow metal so any twisting of the cable is
transfered
to the tag and the ring part can twist and touch the conductor stem to
the
tip, as the cylinder insulation along this stem does not extend into
this
solder tag, or perhaps as only touching ground contact, then localised
heating and the cylinder insulation melting back a bit. I've not
explored
that far in, the top moulded insulation plastic does not look melted.
These elbows have a vague brassy/coppery tinge of plating or something
just
on the tips , the main elbow body is Hex in plan and between it and the
stem
is what looks like a hank bush swage-form.



Several people have reported that their problems began when they started
using speaker cables other than those supplied with the units which
sadly
are just not quite long enough.

Ron


The thing is, Yamahas user manual specifically warns against using speaker
cables other than those supplied with the units, so they are covered.

e.g.

11 Only use attachments/accessories specified by the manufacturer.

and:

To avoid any possible malfunction, use only the speaker cables included
with
the device




Cheers,


Gareth.

Gareth Magennis <sound.service_at_btconnect.com> wrote in message
news:Cv2dnZygeY6aRbrSnZ2dnUVZ7sWdnZ2d_at_bt.com...

"Ron" <ron_at_lunevalleyaudio.com> wrote in message
news:qdadnY1LK8NCTrrSnZ2dnUVZ8rOdnZ2d_at_bt.com...
On 31/01/2012 11:05, N_Cook wrote:
Just as well I'm not paying Yamaha 50 squid a pop for these blown
amps.
Repaired one end of 2011 , it bounced back.
It is due to the short stub lead between amp and its immediate
speaker,
the
elbow connectors.
No name elbows on lead marked UPOFC Classic Pro Loudspeaker Cable.
Took
a
bit of grinding to cut the top off the elbow, quite thick monkey
metal.
The
ground connection out to the cable solder point is like a solder tag
but
with a 2mm x 1mm x tag thickness lug opposite the solder extension
,that
locates into the moulded plastic insulator. The tag is not spot
welded/bolted to the elbow metal so any twisting of the cable is
transfered
to the tag and the ring part can twist and touch the conductor stem to
the
tip, as the cylinder insulation along this stem does not extend into
this
solder tag, or perhaps as only touching ground contact, then localised
heating and the cylinder insulation melting back a bit. I've not
explored
that far in, the top moulded insulation plastic does not look melted.
These elbows have a vague brassy/coppery tinge of plating or something
just
on the tips , the main elbow body is Hex in plan and between it and
the
stem
is what looks like a hank bush swage-form.



Several people have reported that their problems began when they
started
using speaker cables other than those supplied with the units which
sadly
are just not quite long enough.

Ron


The thing is, Yamahas user manual specifically warns against using
speaker
cables other than those supplied with the units, so they are covered.

e.g.

11 Only use attachments/accessories specified by the manufacturer.

and:

To avoid any possible malfunction, use only the speaker cables included
with
the device




Cheers,


Gareth.




The foot long lead is not original Yamaha. The general warning applies
about
these non-moulded , ie user applicable solder-on tags with screw-on
knurled
barrel over the cable entry. The soldering and choice of cable was fine,
it
is a bad design of connector

"N_Cook" <diverse_at_tcp.co.uk> wrote in message
news:jgavsm$d1e$1_at_dont-email.me...
Gareth Magennis <sound.service_at_btconnect.com> wrote in message
news:Cv2dnZygeY6aRbrSnZ2dnUVZ7sWdnZ2d_at_bt.com...

"Ron" <ron_at_lunevalleyaudio.com> wrote in message
news:qdadnY1LK8NCTrrSnZ2dnUVZ8rOdnZ2d_at_bt.com...
On 31/01/2012 11:05, N_Cook wrote:
Just as well I'm not paying Yamaha 50 squid a pop for these blown
amps.
Repaired one end of 2011 , it bounced back.
It is due to the short stub lead between amp and its immediate
speaker,
the
elbow connectors.
No name elbows on lead marked UPOFC Classic Pro Loudspeaker Cable.
Took
a
bit of grinding to cut the top off the elbow, quite thick monkey
metal.
The
ground connection out to the cable solder point is like a solder tag
but
with a 2mm x 1mm x tag thickness lug opposite the solder extension
,that
locates into the moulded plastic insulator. The tag is not spot
welded/bolted to the elbow metal so any twisting of the cable is
transfered
to the tag and the ring part can twist and touch the conductor stem
to
the
tip, as the cylinder insulation along this stem does not extend into
this
solder tag, or perhaps as only touching ground contact, then
localised
heating and the cylinder insulation melting back a bit. I've not
explored
that far in, the top moulded insulation plastic does not look
melted.
These elbows have a vague brassy/coppery tinge of plating or
something
just
on the tips , the main elbow body is Hex in plan and between it and
the
stem
is what looks like a hank bush swage-form.



Several people have reported that their problems began when they
started
using speaker cables other than those supplied with the units which
sadly
are just not quite long enough.

Ron


The thing is, Yamahas user manual specifically warns against using
speaker
cables other than those supplied with the units, so they are covered.

e.g.

11 Only use attachments/accessories specified by the manufacturer.

and:

To avoid any possible malfunction, use only the speaker cables included
with
the device




Cheers,


Gareth.




The foot long lead is not original Yamaha. The general warning applies
about
these non-moulded , ie user applicable solder-on tags with screw-on
knurled
barrel over the cable entry. The soldering and choice of cable was fine,
it
is a bad design of connector





So not really a Yamaha Stagepass 300 failure mode as the thread title
states
then.



Cheers,


Gareth.

It seems its a fault of Yamaha supplying 2 "long" leads only. Or this
owner
from new received only 2 "long" leads and no foot long lead. He got a shop
to make up a foot long lead, and a long-long lead, nothing wrong with the
job they did, unknowingly bad choice of elbows .

It seems its a fault of Yamaha supplying 2 "long" leads only. Or this
owner
from new received only 2 "long" leads and no foot long lead. He got a
shop
to make up a foot long lead, and a long-long lead, nothing wrong with
the
job they did, unknowingly bad choice of elbows .



Well it sounds to me that the "shop" actually made a BAD and ignorant
choice
in the components they used, which ultimately cost the customer a lot of
money.

Doesn't sound like a good job to me at all. Particularly as they no doubt
charged him for the priveledge.



Cheers,



Gareth.

Gareth Magennis <sound.service_at_btconnect.com> wrote in message
news:c%iWq.28607$vf5.25959_at_newsfe14.ams2...

It seems its a fault of Yamaha supplying 2 "long" leads only. Or this
owner
from new received only 2 "long" leads and no foot long lead. He got a
shop
to make up a foot long lead, and a long-long lead, nothing wrong with
the
job they did, unknowingly bad choice of elbows .



Well it sounds to me that the "shop" actually made a BAD and ignorant
choice
in the components they used, which ultimately cost the customer a lot of
money.

Doesn't sound like a good job to me at all. Particularly as they no
doubt
charged him for the priveledge.



Cheers,



Gareth.





with seventh sense of hindsight

"N_Cook" <diverse_at_tcp.co.uk> wrote in message
news:jgdhnm$rm8$1_at_dont-email.me...
Gareth Magennis <sound.service_at_btconnect.com> wrote in message
news:c%iWq.28607$vf5.25959_at_newsfe14.ams2...

It seems its a fault of Yamaha supplying 2 "long" leads only. Or this
owner
from new received only 2 "long" leads and no foot long lead. He got a
shop
to make up a foot long lead, and a long-long lead, nothing wrong with
the
job they did, unknowingly bad choice of elbows .



Well it sounds to me that the "shop" actually made a BAD and ignorant
choice
in the components they used, which ultimately cost the customer a lot
of
money.

Doesn't sound like a good job to me at all. Particularly as they no
doubt
charged him for the priveledge.



Cheers,



Gareth.





with seventh sense of hindsight





I would have to disagree.
I have done a lot of professional wiring in my time, and if you absolutely
HAVE to use jacks for a speaker connection (a terrible choice for all
sorts
of reasons) then you make sure the two connectors cannot ever touch each
other, either by using a proper jack plug (Neutrik) or by sleeving the
soldered terminals in such a way that they will always insulate against
the
kind of problems you describe.

The shop it seems chose a crap jack plug and did not sleeve it, and
charged
the customer for this terrible piece of work, which cost him a lot of
money.


I wouldn't be best pleased.



Cheers,


Gareth.

Gareth Magennis <sound.service_at_btconnect.com> wrote in message
news:7fsWq.30144$vf5.24264_at_newsfe14.ams2...


"N_Cook" <diverse_at_tcp.co.uk> wrote in message
news:jgdhnm$rm8$1_at_dont-email.me...
Gareth Magennis <sound.service_at_btconnect.com> wrote in message
news:c%iWq.28607$vf5.25959_at_newsfe14.ams2...

It seems its a fault of Yamaha supplying 2 "long" leads only. Or
this
owner
from new received only 2 "long" leads and no foot long lead. He got
a
shop
to make up a foot long lead, and a long-long lead, nothing wrong
with
the
job they did, unknowingly bad choice of elbows .



Well it sounds to me that the "shop" actually made a BAD and ignorant
choice
in the components they used, which ultimately cost the customer a lot
of
money.

Doesn't sound like a good job to me at all. Particularly as they no
doubt
charged him for the priveledge.



Cheers,



Gareth.





with seventh sense of hindsight





I would have to disagree.
I have done a lot of professional wiring in my time, and if you
absolutely
HAVE to use jacks for a speaker connection (a terrible choice for all
sorts
of reasons) then you make sure the two connectors cannot ever touch each
other, either by using a proper jack plug (Neutrik) or by sleeving the
soldered terminals in such a way that they will always insulate against
the
kind of problems you describe.

The shop it seems chose a crap jack plug and did not sleeve it, and
charged
the customer for this terrible piece of work, which cost him a lot of
money.


I wouldn't be best pleased.



Cheers,


Gareth.


The first time this amp turned up with a blown amp modulle, that was
probably due to non sleeved connector for the "L" channel, I agree there.
I
sleeved the elbow and added spiral wrap to the handle to avoid that
happening again. The next time would be due to bad design of elbow,
internal
shorting. These look robust jacks from the outside. More robust than those
usual right angle jacks on 100 or 150W combos , very low profile ones.
They
can hardly handle 100W from the number of times I've noticed them warming
from compression of the insulation under the rivet-type central connector
,
if not so loose it is intermittant contact.
Any other makes other than Neutrik proven reliable for 150W upwards?

"N_Cook" <diverse_at_tcp.co.uk> wrote in message
news:jgdnv8$o72$1_at_dont-email.me...
Gareth Magennis <sound.service_at_btconnect.com> wrote in message
news:7fsWq.30144$vf5.24264_at_newsfe14.ams2...


"N_Cook" <diverse_at_tcp.co.uk> wrote in message
news:jgdhnm$rm8$1_at_dont-email.me...
Gareth Magennis <sound.service_at_btconnect.com> wrote in message
news:c%iWq.28607$vf5.25959_at_newsfe14.ams2...

IMHO you should not be using jacks for anything over 150W. Far too Mickey
Mouse, and not designed for that purpose.

I will not use anything other than Neutriks for speaker cables - the cable
grip system is as imporant as the robustness of the jack itself, and
Neutriks (both jacks and XLR's) do not EVER break if wired correctly in
the
first place.

Which is kind of what you need really, in a live situation, as failiure of
speaker cables in particular can destroy your amps as well as your
reputation.


Cheers,



Gareth.

Another identifier , perhaps, for these shoddy elbow jacks, the "hank shank"
section has 32 "teeth" around it