David wrote...

Size?

Assuming this is a similar model (SX-PX 20) then;
the service manual downloadable from...
http://elektrotanya.com/technics_sx-.../download.html
doesn't say much only...

Speaker 1 = 16cm 8ohm
Speaker 2 = 12cm 8 ohm
Speaker 3 = Horn tweeter 16ohm.

It does mention that there are Stereo Left and Right audio outputs on
RCA on the rear panel which if present on your model could possibly be
used if no luck with the speaker(s).


To download the SM you should click the small red left and right arrows
to the right of the cover image to view several ads, a "Get manual" link
will eventually show and it will then download.


--
Ken O'Meara
http://www.btinternet.com/~unsteadyken/

"UnsteadyKen" wrote in message
om...

David wrote...

Size?

Assuming this is a similar model (SX-PX 20) then;
the service manual downloadable from...
http://elektrotanya.com/technics_sx-.../download.html
doesn't say much only...

Speaker 1 = 16cm 8ohm
Speaker 2 = 12cm 8 ohm
Speaker 3 = Horn tweeter 16ohm.

It does mention that there are Stereo Left and Right audio outputs on
RCA on the rear panel which if present on your model could possibly be
used if no luck with the speaker(s).


To download the SM you should click the small red left and right arrows
to the right of the cover image to view several ads, a "Get manual" link
will eventually show and it will then download.


Thank you Ken, that's fantastic.
I'll have a listen to see which speaker has blown (assuming it is a
speaker), but at least it's not stereo so only need to replace one.
Will let you all know how I get on.

David

In article , David


Thank you Ken, that's fantastic. I'll have a listen to see which speaker
has blown (assuming it is a speaker), but at least it's not stereo so
only need to replace one. Will let you all know how I get on.

Erm... You now say *assuming* it is a speaker. Whereas you initially said
it *was*.

What are the actual symptoms, and what makes you think it is a *speaker* as
distinct from, say, a broken wire in the unit or a blow amp (or its fuse)
or various other possibly problems?

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

"Jim Lesurf" wrote in message
...
In article , David


Thank you Ken, that's fantastic. I'll have a listen to see which speaker
has blown (assuming it is a speaker), but at least it's not stereo so
only need to replace one. Will let you all know how I get on.

Erm... You now say *assuming* it is a speaker. Whereas you initially said
it *was*.

What are the actual symptoms, and what makes you think it is a *speaker*
as
distinct from, say, a broken wire in the unit or a blow amp (or its fuse)
or various other possibly problems?


I'm not 100% that it's the speaker but it sounds like a bass drive unit
fault. It buzzes at certain frequencies. The drive units still work. I'm
not sure how to diagnose what it actually is without replacing various bits.

I'll have a listen tonight to see if I get a better idea.
How would I tell whether it's an amp or speaker problem?

Thank you

David

In article , David
wrote:
"Jim Lesurf" wrote in message
...


What are the actual symptoms, and what makes you think it is a
*speaker* as distinct from, say, a broken wire in the unit or a blow
amp (or its fuse) or various other possibly problems?


I'm not 100% that it's the speaker but it sounds like a bass drive unit
fault. It buzzes at certain frequencies. The drive units still work.
I'm not sure how to diagnose what it actually is without replacing
various bits.

The 'buzzing' you report is useful as a symptom. It rules out various
things which other behaviour might have caused. The speaker being damaged
sounds plausible, although it might perhaps be something else like a poor
connection rattling or a loose wire against the cone.

If you'd said the speaker had fallen silent, then it might have been a
broken connection or an amp or channel fuse failure. 'Buzzing' might still
be the amp. But the speaker is a better bet I'd think.

I'll have a listen tonight to see if I get a better idea. How would I
tell whether it's an amp or speaker problem?

If the unit is 'stereo' (has two sets of speakers and two amps in this
case) you can check by swapping over the connections so that which amp
drives which channel is swapped. If the symptoms stay with the speaker, it
points to a speaker problem. If they follow the amp, an amp problem.

However the 'buzz' does seem like a speaker problem.

You might find it is a loose wire that can be reconnected or moved to avoid
it touching the cone of the speaker. You may even find that rotating the
speaker top-bottom will help if the speaker unit has 'sagged' under
gravity. If there is no obvious mechanical damage such experiments might be
worth a try. If they work, good. If not, you are no worse off for trying.

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

"Jim Lesurf"

The 'buzzing' you report is useful as a symptom. It rules out various
things which other behaviour might have caused. The speaker being damaged
sounds plausible, although it might perhaps be something else like a poor
connection rattling or a loose wire against the cone.


** If you were a service tech Jim, you would FIRST suspect a foreign
object.

It's an electric piano - so the speakers typically face upwards through a
slotted grille that small objects can fall through.

Makes a nasty distorted sound that is very level and note dependant.

Occam's Razor rules...........




..... Phil

"Phil Allison" wrote in message ...

** If you were a service tech Jim, you would FIRST suspect a foreign
object.

It's an electric piano - so the speakers typically face
upwards through a slotted grille that small objects
can fall through.

Makes a nasty distorted sound that is very level and note dependant.

Well in this case and with most and possibly all Technics pianos, they face
downwards so pretty unlikely.

D

"Jim Lesurf" wrote in message
...

However the 'buzz' does seem like a speaker problem.


Jim. I received an e-mail in reply to my post
in this thread, from a UK service tech in
Hertforshire.

He told how he too had removed a suspect speaker that
rattled and buzzed, from a Roland stage piano, just as I
had done.

As he took the speaker out, something that had been
wedged between the cone and the spider, fell to the floor.
It was a nickel-brass threepenny bit, of 1953 vintage.

One wonders how it got there. It predates
the piano by more than forty years.

I know little about numismatics, but I wondered
which was worth more, the coin or the piano-)


Iain

In article , Iain Churches
wrote:

"Jim Lesurf" wrote in message
...

However the 'buzz' does seem like a speaker problem.


Jim. I received an e-mail in reply to my post in this thread, from a
UK service tech in Hertforshire.

He told how he too had removed a suspect speaker that rattled and
buzzed, from a Roland stage piano, just as I had done.

As he took the speaker out, something that had been wedged between the
cone and the spider, fell to the floor. It was a nickel-brass threepenny
bit, of 1953 vintage.

Alas, that means I can't do a joke about "at that point, the penny
dropped". :-)

One wonders how it got there. It predates the piano by more than forty
years.

Ghost in the Machine? 8-]

Or maybe a passerby throwing an old coin into the piano thinking of the old
'prepared piano' works. Do you think those with a preference for 'period
performance' would argue that coins of the vintage of the *composition*
would be required even for an electric piano?

I know little about numismatics, but I wondered which was worth more,
the coin or the piano-)

Our piano is a 'pianola', alas with the mechanism in something of a mess
due to all the rubber, etc, perishing. I think I have some thrupenny bits
somewhere. I've assumed they aren't particularly valuable, however I'm no
numasmatist, either!

That said, I seem to increasingly confirm my own view that we find
'history' more interesting as we come to recall being present for more of
it. Hence the page I put up recently on Concorde 001 and the 1973 Eclipse.
Which *is* slightly on-topic here. I used a Revox A77 as the data recorder.
I still have the tape, but not the recorder. :-)

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

"Iain Churchus = Nong "

He told how he too had removed a suspect speaker that
rattled and buzzed, from a Roland stage piano, just as I
had done.

As he took the speaker out, something that had been
wedged between the cone and the spider, fell to the floor.
It was a nickel-brass threepenny bit, of 1953 vintage.

One wonders how it got there.


** The gap above the keys would allow a coin inside.

Then the piano gets moved around.


It predates the piano by more than forty years.


** So ****ing what ?



..... Phil