The Yamaha AN1x Synthesizer mailing list

Wall Warts

In a previous job I was a Test Engineer for an independent standards and
compliance lab.  We tested many types of equipment to different regulations
and rules - governmental, military, insurance, whatever.  I personally had
the privilege of working with Korg, Shure, ATT, IBM and other big names.
Here's what I learned about wall warts:

In the USA, the testing requirements for electrical saftey are different for
products which require less than 48 volts input to the chassis.  If a
product required more, it needed to meet tougher standards to be allowed to
be sold, and these standards often would require more circuitry, and
therefore would be more expensive.  Therefore, a lot of companies chose to
have the AC converted down to less than 48 volts through a power converter
(wall wart) and then sent to the device through a small twin lead wire
ending in a small plug.  This design decision was nothing more than a cost
saving feature (detriment) in many cases.

My personal advice on gear that uses wall warts is to make very sure that
you have routed the tiny, skinny cable in a way that nobody trips over it.
I have repaired many circuit boards that were really hurt by a kick or an
unexpected pull on these hard to see wires.  I try to route mine down the
side of the keyboard stand and even sometimes tape it down for safety.

Equipment that has the standard IEC male receptacle on the back - that takes
the fully detachable and rugged cable which gets the full AC voltage from
the wall (and is international in design) is much more rugged in general,
surviving trip overs and other abuse...  It is much more "road worthy".

Generally, all of the curcuitry in a wall wart is usually this: a
transformer, some diodes and maybe some capacitors.  These components can be
easily built into the unit.  Tawdry and cheap design is why we suffer with
these stupid warty chunks of plastic and metal that take up so much space.
In the back of my 12 space rack I have to stuff 5 ugly wall warts which
hardly fit.

Ed Edwards
Leader: Ezekiel's Wheel\ufffd      \ufffd\ufffd\ufffd\ufffdRetro-Progressive Rock\ufffd\ufffd\ufffd\ufffd
http://www.untiedmusic.com/ezekiel
http://artists.mp3s.com/artists/227/ezekiels_wheel.html
\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd
\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd

At 12:30 AM 10/1/01 -0400, Ed Edwards wrote:
>
>Generally, all of the curcuitry in a wall wart is usually this: a
>transformer, some diodes and maybe some capacitors.  These components can be
>easily built into the unit.  Tawdry and cheap design is why we suffer with
>these stupid warty chunks of plastic and metal that take up so much space.
>In the back of my 12 space rack I have to stuff 5 ugly wall warts which
>hardly fit.
>

I heard the real reason that companies use wall-warts for their products is 
because for any product with a power transformer, it requires UL (or 
equivalent) approval. But if the transformer is in the form of an external 
AC unit (wall wart), and the particular wall wart already had its UL 
approval years ago, manufacturers can release any number of products 
without having to get individual UL approval for them.



- 30 -
: . elson trinidad, los angeles, california, usa
: . elson@...  :  www.westworld.com/~elson
: . groove to the futurethnic beats of e:trinity at www.e-trinity.org and 
www.mp3.com/etrinity


[Non-text portions of this message have been removed]

Right.  Exactly what I'm saying.  CHEAPNESS.  TAWDRY.  EASY TO GET BY.

The company I worked for was a competitor of UL.  UL is NOT a government
agency, but is a test house, as was MET Laboratories, where I worked.

Ed Edwards
Leader: Ezekiel's Wheel\ufffd      \ufffd\ufffd\ufffd\ufffdRetro-Progressive Rock\ufffd\ufffd\ufffd\ufffd
http://www.untiedmusic.com/ezekiel
http://artists.mp3s.com/artists/227/ezekiels_wheel.html
\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd
\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd


----- Original Message -----
From: "Elson Trinidad" <elson@...>
To: <AN1x-list@yahoogroups.com>; <AN1x-list@yahoogroups.com>
Sent: Monday, October 01, 2001 1:03 AM
Subject: Re: [AN1x-list] an1x construction. (Wall Warts of all sorts)


> At 12:30 AM 10/1/01 -0400, Ed Edwards wrote:
> >
> >Generally, all of the curcuitry in a wall wart is usually this: a
> >transformer, some diodes and maybe some capacitors.  These components can
be
> >easily built into the unit.  Tawdry and cheap design is why we suffer
with
> >these stupid warty chunks of plastic and metal that take up so much
space.
> >In the back of my 12 space rack I have to stuff 5 ugly wall warts which
> >hardly fit.
> >
>
> I heard the real reason that companies use wall-warts for their products
is

> because for any product with a power transformer, it requires UL (or
> equivalent) approval. But if the transformer is in the form of an external
> AC unit (wall wart), and the particular wall wart already had its UL
> approval years ago, manufacturers can release any number of products
> without having to get individual UL approval for them.
>
>
>
> - 30 -
> : . elson trinidad, los angeles, california, usa
> : . elson@...  :  www.westworld.com/~elson
> : . groove to the futurethnic beats of e:trinity at www.e-trinity.org and
> www.mp3.com/etrinity
>
>
> [Non-text portions of this message have been removed]
>
>
>
> Community email addresses:
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>

> Right.  Exactly what I'm saying.  CHEAPNESS.  TAWDRY.  EASY TO GET BY.

Using wall wart you can also make only one model of synth and in a packing
state just inlcude the right wall wart regarding is the unit shipped to
Europe or States ?

I suppose that it costs much less this way for manufacturer?

Cheers,
TimoS

All,

>Right.  Exactly what I'm saying.  CHEAPNESS.  TAWDRY.  EASY TO GET BY.

It's not that black and white...

Having been on the other side of the problem -- I've designed products for 
years -- I can understand the reason for the shift to wall 
warts.  Personally, I hate them, but it's a necessity brought on by the 
short product design cycles in modern consumer electronics.

If you make a line/mains-powered product, and plan to sell it in more than 
one country, the power supply is going to have to acquire a series of 
certifications from regulatory agencies.  For the most part, each country 
is reluctant to just "rubber stamp" their approval on top of another 
country -- sometimes because of differences in the power distribution and 
grounding schemes between countries; sometimes because different countries 
put a higher or lower merit on certain designs and design flaws; sometimes, 
just good old politics -- so samples of the products have to be submitted 
to each agency.

Afterwards, the samples have to be tracked and the results monitored, in 
case a problem arises.  (A sad truth:  If a locally-developed product has a 
certification problem, the agency will likely call the manufacturer to 
discuss the issues; if the product is from another country, it may just end 
up in a big "hold" pile until the manufacturer takes the first 
initiative.)  This requires a full-time compliance group within the 
company, who are aware of all the subtleties (and personalities) among the 
various agencies, and who have the bandwidth to keep tabs on the open 
certifications.  Or, it requires contracting with an outside agency to do 
the submittal and monitoring.  Most of these agencies get $1,000US/day or 
more for their services.

Either way, the process can take months; occasionally, a year or more, and 
the costs get passed on to the customer.  In the case of mass-produced 
products like CD players and PCs, the cost is small per unit sold, but 
musical instruments rarely sell at the same levels, so the cost adder could 
end up being significant -- maybe 5% of the total product cost.  And, it 
means that a product could be late to market, if it gets stuck in an agency 
queue for some reason.

OR, a wall wart design passes off all of the above unpleasantness to the 
power supply manufacturer.  In most cases, the power supply is already in 
production, so the delay between development and production is greatly 
reduced, often to a paper-only submittal.  Finally, power supply design and 
manufacture is a "mature" industry, where several companies may make 
suitable designs, allowing the musical equipment manufacturer to select 
product based solely on cost and availability.  Can you see why so many 
manufacturers have gone this route?

We all enjoy the fact that musical electronics today produce great 
sounding, flexible products at comparatively cheap prices.  (How many 
performing acts in the 60's and 70's could afford to carry around even ONE 
delay/reverb unit?  Most bands today have a dozen or more, counting the 
built-in effects in keyboards and guitar amps.)  There is the down side of 
the equation, however; it's call the wall wart.


Regards,

-BW

--
Bruce Wahler
Design Consultant
Ashby Solutions™
www.ashbysolutions.com
CloneWheel Support Group moderator
978.386.7389  voice
978.964.0547 fax
bruce@...

If we're gonna have wall warts, at least give us the kind that have the 
transformer box sit on the floor while one cord goes to the unit and 
another goes to the power socket -- the kind that doesn't take up more than 
one socket in a power strip.


- 30 -
: . elson trinidad, los angeles, california, usa
: . elson@...  :  www.westworld.com/~elson
: . groove to the futurethnic beats of e:trinity at www.e-trinity.org and 
www.mp3.com/etrinity


[Non-text portions of this message have been removed]

From: "Bruce Wahler" <bruce@...>

> [as per usual, a thorough and interesting explantion]

Could it be an idea to use standard power supplies, that you just shove into
your piece of equipment? All synths take the same voltages (12v, 5v,
0v, -12v I'd imagine) anyway.

- Peter

Peter,

>Could it be an idea to use standard power supplies, that you just shove into
>your piece of equipment? All synths take the same voltages (12v, 5v,
>0v, -12v I'd imagine) anyway.

That approach is often used, and it helps with the time-to-market, but it 
doesn't solve the main issue:  power hazards inside the box.  Regulatory 
agencies say to the manufacturers, "Look you're responsible for any power 
that goes INSIDE your devices; your not responsible for anything that goes 
on OUTSIDE the devices."  Then they define a fairly difficult set of 
standards for voltages above 40-50V, and an easier set of rules for lower 
voltages.  Why?  Because the safety of electrical products is based on two 
things:  the distance between parts at different voltages, which affects 
the tendency to arc or short-circuit; and the amount of power that might be 
dumped into a device in the case of a failure, causing fire.  In both 
cases, the higher the voltage, the more likely that the result is hazardous.

As a designer, if I allow 120/240V into a product, I have to demonstrate 
that there is an extremely low chance of that voltage linking to a part 
that would either a) shock the user or b) cause a fire.  Because of the 
nature of high voltages -- i.e., their increased ability to arc through the 
air or break through insulating materials -- this can be difficult, 
especially in small spaces.  If I can lower the voltage, many of the 
problem areas become safe.  It also becomes easier to demonstrate their 
safety, so I win twice.

Regards,

-BW

--
Bruce Wahler
Design Consultant
Ashby Solutions™
www.ashbysolutions.com
CloneWheel Support Group moderator
978.386.7389  voice
978.964.0547 fax
bruce@ashbysolutions.com

Bruce,
    Sounds like we ought to start a company together - we've already got the
design and compliance sides of it covered.  Now all we need is capital....
:\ufffd/

And now for a useful post to the group:

When I received my AN1x, it was one of the last units that Guitar Center had
in the US.  The box had been opened, but the synth never removed and they
kindly cut the price further.  I excitedly set it up when I got it and was
of course blown away by what it could do.  But it started making some
horrible toilet kind of sounds and the LEDs would blink without prompting
and sometimes I couldn't change patches.  Bummer, I thought, a bad unit.  So
I called Yamaha warranty and began to arrange to ship it to them for repair.
While taking the serial number from me they asked me to include the YA-3
power supply.  I told them that I had another model and the guy puts me on
hold.  Reason for problem- Guitar Center had sent the wrong supply.  It had
the right voltage, DC 10V, but not enough current, 700 mA.   Conclusion - if
your wall wart goes dead, always replace it with one that can supply enough
current.  10 volts at 500 mA didn't work.

Ed Edwards
Leader: Ezekiel's Wheel\ufffd      \ufffd\ufffd\ufffd\ufffdRetro-Progressive Rock\ufffd\ufffd\ufffd\ufffd
http://www.untiedmusic.com/ezekiel
http://artists.mp3s.com/artists/227/ezekiels_wheel.html
\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd
\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd

--- In AN1x-list@y..., "Ed Edwards" <edward.edwards@v...> wrote:
if
> your wall wart goes dead, always replace it with one that can 
supply enough
> current.  10 volts at 500 mA didn't work.
> °·.·°·.·°·.·°·.·°

Well, let me ask a useful question: Too much electricity can kill 
your equipment, can not enough electricity kill your equipment too? 
Did your AN1x still worked after replacing the wall wart?

--Tom

Elson,

>If we're gonna have wall warts, at least give us the kind that have the
>transformer box sit on the floor while one cord goes to the unit and
>another goes to the power socket -- the kind that doesn't take up more than
>one socket in a power strip.

... which brings us back around to my earlier statement:  Replace your wall 
wart with a switching power supply adapter.  They're a little more money, 
but they're lighter, higher power, work over a wide range of voltages (in 
case you travel to gig), and tend to be more reliable.  The AC cord usually 
comes off, too, making it easier to store.

Regards,

-BW

--
Bruce Wahler
Design Consultant
Ashby Solutions™
www.ashbysolutions.com
CloneWheel Support Group moderator
978.386.7389  voice
978.964.0547 fax
bruce@...

>Well, let me ask a useful question: Too much electricity can kill
>your equipment, can not enough electricity kill your equipment too?
>Did your AN1x still worked after replacing the wall wart?
>
>--Tom

Yeah, it's continually worked fine since I got the correct transformer - but
here we're talking about one particular peice of gear.  I can't think of a
circuit which would be killed by low current levels (well, maybe some
special applications stuff).  Take a portable radio, for example.  From the
time you put batteries in it the current and voltage supply are diminishing.
You can play it until it distorts like mad and you can hardly hear it,
replace the batteries, and it's fine.

Look, we're mostly musicians here, not electronics techs.  If the power
supply of something craps out, find the "correct" replacement.

Here's a laugh:
When I grabbed the AN1x wall wart to look at it, it was warm, REALLY warm -
and the AN1x has been off since Sunday!!!  How can this be, you may ask?
Because due to design (apologies here Bruce and others), the stupid thing is
drawing current all of the time!  Transformers are like that, even when the
secondary coil has no load, the primary still has it's own internal
impedance and pulls current and costs money.  So, when the AN1x is off, it
really isn't completely off....

Ed Edwards
Leader: Ezekiel's Wheel\ufffd      \ufffd\ufffd\ufffd\ufffdRetro-Progressive Rock\ufffd\ufffd\ufffd\ufffd
http://www.untiedmusic.com/ezekiel
http://artists.mp3s.com/artists/227/ezekiels_wheel.html
\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd

From: "Thomas" <tomfinegan@...>

> Well, let me ask a useful question: Too much electricity can kill
> your equipment, can not enough electricity kill your equipment too?
> Did your AN1x still worked after replacing the wall wart?

Not enough power will never damage equipment. It's not like your car brakes
down if you only drive it at 30 km/h. (Well, it's a little more complicated
than that, but you catch my drift.)

- Peter

--- In AN1x-list@y..., "Ed Edwards" <edward.edwards@v...> 
wrote:
> Here's a laugh:
> When I grabbed the AN1x wall wart to look at it, it was warm, 
REALLY warm -
> and the AN1x has been off since Sunday!!!  How can this be, 
you may ask?
> Because due to design (apologies here Bruce and others), the 
stupid thing is
> drawing current all of the time!  Transformers are like that, even 
when the
> secondary coil has no load, the primary still has it's own 
internal
> impedance and pulls current and costs money.  So, when the 
AN1x is off, it
> really isn't completely off....

This doesn't sound right to me. I've not had my AN1x turned on 
all week and the Pa-3B power supply (factory supplied) is stone 
cold to the touch.

regards,

Jon

PA-3B!!!!   Yamaha sent me a YA-3.  (???)

Jon, could you please tell me what ratings are printed on the outside of the
PA-3B?


Ed Edwards
Leader: Ezekiel's Wheel\ufffd      \ufffd\ufffd\ufffd\ufffdRetro-Progressive Rock\ufffd\ufffd\ufffd\ufffd
http://www.untiedmusic.com/ezekiel
http://artists.mp3s.com/artists/227/ezekiels_wheel.html
\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd
\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd\ufffd.\ufffd\ufffd


----- Original Message -----

From: <jondl_2000@...>
To: <AN1x-list@yahoogroups.com>
Sent: Tuesday, October 02, 2001 5:48 PM
Subject: [AN1x-list] Re: an1x construction. (Wall Warts of all sorts)


> --- In AN1x-list@y..., "Ed Edwards" <edward.edwards@v...>
> wrote:
> > Here's a laugh:
> > When I grabbed the AN1x wall wart to look at it, it was warm,
> REALLY warm -
> > and the AN1x has been off since Sunday!!!  How can this be,
> you may ask?
> > Because due to design (apologies here Bruce and others), the
> stupid thing is
> > drawing current all of the time!  Transformers are like that, even
> when the
> > secondary coil has no load, the primary still has it's own
> internal
> > impedance and pulls current and costs money.  So, when the
> AN1x is off, it
> > really isn't completely off....
>
> This doesn't sound right to me. I've not had my AN1x turned on
> all week and the Pa-3B power supply (factory supplied) is stone
> cold to the touch.
>
> regards,
>
> Jon
>
>
>
> Community email addresses:
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>
>

Ed,

The YA-3/PA-3 is the older model, rated at (I believe) 10V and 700mA.  (I 
have a replacement supply by Mutec that claims to be the "same 
specifications as the Yamaha PA-3," and that's what it is rated at.)

The replacement PA-3B, which came with my AN1x, is rated at 12V and 
700mA.  I have both, and both SEEM to work with the AN1x, as do laptop 
switcher supplies of 11V @ 1.9A and 12V @ 1.25A that I have lying around.

I suspect that the whole insides of the AN1x are powered by 5VDC, and so 
any supply of 8V or greater should work.  I could be mistaken, though.

Regards,

-BW

--
Bruce Wahler
Design Consultant
Ashby Solutions™
www.ashbysolutions.com
CloneWheel Support Group moderator
978.386.7389  voice
978.964.0547 fax
bruce@ashbysolutions.com

At 06:12 P 10/2/2001 -0400, you wrote:

>PA-3B!!!!   Yamaha sent me a YA-3.  (???)
>
>Jon, could you please tell me what ratings are printed on the outside of the
>PA-3B?
>
>
>Ed Edwards
>Leader: Ezekiel's Wheel®      »»»»Retro-Progressive Rock««««
><http://www.untiedmusic.com/ezekiel>http://www.untiedmusic.com/ezekiel
>http://artists.mp3s.com/artists/227/ezekiels_wheel.html
>°·.·°·.·°·.·°·.·°·.·°·.·°·.·°·.·°·.·°·.·°·.·°·.·°·.·°·.·°·.·°·.·°·.·°
>°·.·°·.·°·.·°·.·°
>