online pitch source (precision of your A440 reference ?)

[Philippe Errembault]

This makes me wonder... Do you usually have an idea of the precision of the
A440 reference you
use ? I mean... I didn't get any the precision information with my tuning
fork, I found it on the net.
I wonder what are the precisions of professional ETDs, and what precision we
can expect from a
pocket PC, about which I wonder if it even can be as precise as a normal
PC...

In fact, I have one reason to think it could even be better : since this
material is intended to be as small
as possible, it might be that they only contain ONE reference clock, for
time, for CPU and for sound
processing. Then, we could expect the sound precision to be as precise as
their time clock... did any
of you ever tried to check his pocket PC, against a good A440 reference, and
compare the error with
the time drift ? (and by the way, compare it with a desktop PC)
Reminder : 0.1cent = ~0.0058% = ~5sec/day

Philippe Errembault

Ps : I know the buffering of cell phone is small, but this doesn't change
the fact that any shift in it's clock
should be retrieved in the output ! this would lead to an interresting
experiment :
take two cell phone, call the same tone reference and see if there is any
beat between them...
I would be curious about the result !

----- Original Message ----- 
From: "Philippe Errembault" <phil.errembault at skynet.be>
To: "Pianotech List" <pianotech at ptg.org>
Sent: Tuesday, May 16, 2006 12:46 AM
Subject: Re: online pitch source


> Ok, criticise the precision of your PCs, but do you have any idea how
> precise is your tuning fork ?
> I have found on the net that a steel tuning fork can be as precise as 0.05
> Hz while an aluminium one
> would start a 0.2 Hz, quickly degrading to 0,5 Hz
>
> I think a PC with a common soundcard, playing a calibrated wave file is
...
> not to be compared
> with a steel fork, but probably as precise as a common aluminium fork...
>
> If you use tune lab after having properly calibrated it, then it can be as
> precise as a steel tuning fork.
>
> Philippe Errembault
>
>
> ----- Original Message ----- 
> From: "Sid Blum" <piano at sover.net>
> To: "Pianotech List" <pianotech at ptg.org>
> Sent: Monday, May 15, 2006 11:52 PM
> Subject: RE: online pitch source
>
>
> > All this discussion gets me to thinking oscilloscopes, microphones,
> > and especially tuning forks aren't so bad after all.
> > -- 
> > Sid Blum
> > sid at sover.net
> >
> >
>
>
>