Advice: Amp building
 

On 27 Jul 2006 06:01:27 -0700, "Andy Evans"
wrote:

c) Check his laptimes - if they are better, assume he was right....

But that assumption would be faith based, since you can't be sure what
to attribute the change to

Once you are at the stage of fine tuning, you know exactly what to
attribute changes to - I don't think anybody in motor racing employs
the Taguchi method. You make one change and measure - if it is better,
go a bit further until you peak. Then you start on the next parameter
and do it again. Once everything is as good as it gets, you go back to
the beginning and start again because everything interacts. Some
parameters you adjust in pairs because the interaction is first order
A bit like amplifier development in some ways.

d

--
Pearce Consulting
http://www.pearce.uk.com

Advice: Amp building
 

You make one change and measure - if it is better,
go a bit further until you peak. Then you start on the next parameter
and do it again. Once everything is as good as it gets, you go back to
the beginning and start again because everything interacts. Some
parameters you adjust in pairs because the interaction is first order
A bit like amplifier development in some ways.

This is a succinct, informative and practical explanation of product
development, and it sounds a hell of a lot like amplifier development
to me. You obviously have the benefit of experience here - from what
you say a lot of your work was extremely practical and solution
orientated in nature (and include the hard climates and adverse
circumstances.....!!!) Andy.

Advice: Amp building
 

Don Pearce wrote:

On Thu, 27 Jul 2006 13:37:22 +0100, Eiron wrote:


Andy Evans wrote:

The only person banging on about 'magical properties' in this group is
you....

Let's try an analogy to see if we can;t go a bit further than
"everything not substantiated in a double blind test (preferably
repeated) is magical and faith based"

Schumacher regularly tests out different motor and suspension tweaks in
his Ferrari. He gets back to the pits and says "this suspension mod is
clearly better"

What do the team do?
a) Dismiss this as magical and faith based and leave the car
unmodified, as it was worked out in theory on the drawing board?
b) Make a working assumption that Schumacher is right and use the mod
in the next race and then make a post-race evaluation?

c) Check his laptimes - if they are better, assume he was right....


He will tell them how it felt. The telemetry will tell them how it
went. He will put up with an awful lot of feeling bad for a tenth of a
second a lap. That was a poorly thought-through analogy, I'm afraid -
from your point of view anyway.

No, it was a good analogy. Do you build the best (most accurate) amp or do you give
it some distortion and alter the frequency response, which the user may prefer?

--
Eiron

No good deed ever goes unpunished.

Advice: Amp building
 

I don't think anybody in motor racing employs the Taguchi method.

I imagine formula one is about the optimisation to the nth degree of
one or two vehicles - maybe an analogy with DIY search for the best
possible amplifier. The way I see Taguchi is kind of after the creative
process and more into product finalisation, the robust design referring
to minimal variance in tolerances. I imagine this is much more
important to high volume production than individual experiments. Is
this what you were referring to, Don?

Advice: Amp building
 

On 27 Jul 2006 07:17:43 -0700, "Andy Evans"
wrote:

You make one change and measure - if it is better,
go a bit further until you peak. Then you start on the next parameter
and do it again. Once everything is as good as it gets, you go back to
the beginning and start again because everything interacts. Some
parameters you adjust in pairs because the interaction is first order
A bit like amplifier development in some ways.

This is a succinct, informative and practical explanation of product
development, and it sounds a hell of a lot like amplifier development
to me. You obviously have the benefit of experience here - from what
you say a lot of your work was extremely practical and solution
orientated in nature (and include the hard climates and adverse
circumstances.....!!!) Andy.

Yup that was way back when. It was all a bit more demanding than
amplifier development though. I was designing microwave and RF
measuring instruments for Marconi Instruments. The requirements were
many tens of dBs better than anything audio demands. The iterative
process was frequently something like 10 micron increments in the
length of a track connecting a FET gate. I would build a bunch at once
with all the different lengths, then evaluate them.

d

--
Pearce Consulting
http://www.pearce.uk.com

Advice: Amp building
 

On Thu, 27 Jul 2006 15:30:02 +0100, Eiron wrote:

No, it was a good analogy. Do you build the best (most accurate) amp or do you give
it some distortion and alter the frequency response, which the user may prefer?

If you were making chairs, would you make them all with one leg
shorter? That would make sense because no floor is truly flat, and
sometimes it might happen that your wonky chair would sit beautifully
over the bumps.

No, that wouldn't be terribly sensible. You make the chairs as well as
you can within your cost constraints.

d

--
Pearce Consulting
http://www.pearce.uk.com

Advice: Amp building
 

On 27 Jul 2006 07:31:58 -0700, "Andy Evans"
wrote:

I don't think anybody in motor racing employs the Taguchi method.

I imagine formula one is about the optimisation to the nth degree of
one or two vehicles - maybe an analogy with DIY search for the best
possible amplifier. The way I see Taguchi is kind of after the creative
process and more into product finalisation, the robust design referring
to minimal variance in tolerances. I imagine this is much more
important to high volume production than individual experiments. Is
this what you were referring to, Don?

Yes - you do need quantity for Taguchi to make sense - then it can
arrive at an optimum rather quicker than the one-thing-at-a-time
method.

d

--
Pearce Consulting
http://www.pearce.uk.com

Advice: Amp building
 

Don Pearce wrote:

On Thu, 27 Jul 2006 15:30:02 +0100, Eiron wrote:


No, it was a good analogy. Do you build the best (most accurate) amp or do you give
it some distortion and alter the frequency response, which the user may prefer?


If you were making chairs, would you make them all with one leg
shorter? That would make sense because no floor is truly flat, and
sometimes it might happen that your wonky chair would sit beautifully
over the bumps.

No, that wouldn't be terribly sensible. You make the chairs as well as
you can within your cost constraints.

Make them with three legs and bugger the tolerances. :-)

--
Eiron

No good deed ever goes unpunished.

Advice: Amp building
 

On Thu, 27 Jul 2006 15:44:09 +0100, Eiron wrote:

Don Pearce wrote:

On Thu, 27 Jul 2006 15:30:02 +0100, Eiron wrote:


No, it was a good analogy. Do you build the best (most accurate) amp or do you give
it some distortion and alter the frequency response, which the user may prefer?


If you were making chairs, would you make them all with one leg
shorter? That would make sense because no floor is truly flat, and
sometimes it might happen that your wonky chair would sit beautifully
over the bumps.

No, that wouldn't be terribly sensible. You make the chairs as well as
you can within your cost constraints.

Make them with three legs and bugger the tolerances. :-)

I'll phone Honda! Maybe we can get Jenson going a bit quicker in a
three wheeler...

d

--
Pearce Consulting
http://www.pearce.uk.com

Advice: Amp building
 

Make them with three legs and bugger the tolerances. :-)

If you can't obtain a balanced result you could make them with one leg
(single ended) and bugger everything. This would, of course place more
demands on the user. The design concept is quite popular in horse
racing punters. My deduction would obviously be that single ended
amplifiers would sell better in the Republic of Ireland. I'm willing to
do a double blind test if I can find two blind Irishmen.