Prev: day shot to hell
Next: Ping Bil Slowman; The global warming hoax reveiled
From: TTman on 21 Nov 2009 04:56
100Watts, runs from a 1.5V battery . Yes, that's correct ! So that would be
a 500AHr. single nicad then, with a 2C charger.
Its true !
http://www.audiumsemi.com/


From: Jan Panteltje on 21 Nov 2009 07:17
On a sunny day (Sat, 21 Nov 2009 09:56:56 -0000) it happened "TTman"
<someone.pc(a)ntlworld.com> wrote in <PPONm.21138$2E.3148(a)newsfe20.ams2>:

>100Watts, runs from a 1.5V battery . Yes, that's correct ! So that would be
>a 500AHr. single nicad then, with a 2C charger.
>Its true !
>http://www.audiumsemi.com/
>
>

Links to:
http://www.audiumsemi.com/news002.php
100 W *peak* power output.
That would be 100 mW normal RMS?
From: Dave Platt on 21 Nov 2009 11:10

>>100Watts, runs from a 1.5V battery . Yes, that's correct ! So that would be
>>a 500AHr. single nicad then, with a 2C charger.
>>Its true !
>>http://www.audiumsemi.com/

>Links to:
> http://www.audiumsemi.com/news002.php
>100 W *peak* power output.
>That would be 100 mW normal RMS?

Something like that, I suspect. The footnote on their October 9th
news article says:

[1] Normal listening level is defined as 73dBC sound pressure level
(SPL) at a distance of 1 metre, with a speaker sensitivity of 89dBC/W
at 1 metre.

Quiet background music, from relatively efficient speakers located
only a few feet from you. -16 dBW, or only 25 milliwatts of audio
delivered to the speakers.

Let's see... "up to 10 months on a set of four C batteries, playing
for up to three hours per day." That's 300 days, 900 operating hours,
45 watt-hours (assuming 100% efficiency), or 15 amp-hours at 1.5 volts.

According to The Great Dubious Reference (WikiPedia) alkaline C
batteries have a nominal capacity of 8530 mAh. Four of them in
parallel would have about 35 amp-hours of energy, which is
quite a bit more than the 15 amp-hours which would need to be
delivered to the speakers. Required "battery in to audio out"
electrical efficiency would be around 40%.

So, it seems to me that their claims don't necessarily violate the
laws of physics... assuming high efficiency in the amp, the sound
level and speaker sensitivity that they assert, and the "up to 10
months" and "up to three hours per day" boundaries. They don't seem
to specify frequency response, distortion, or noise levels.

They'd need a *very* different power supply arrangement in order for
the "100 watt" number they quote to be even slightly relevant and
believable.

Seems as if it may be an interesting niche product.

--
Dave Platt <dplatt(a)radagast.org> AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!
From: Ralph Barone on 21 Nov 2009 20:01
In article <PPONm.21138$2E.3148(a)newsfe20.ams2>,
"TTman" <someone.pc(a)ntlworld.com> wrote:

> 100Watts, runs from a 1.5V battery . Yes, that's correct ! So that would be
> a 500AHr. single nicad then, with a 2C charger.
> Its true !
> http://www.audiumsemi.com/

And also "is 20 times more efficient than competing devices, such as
Class D amplifiers...". Well, that spec is obviously not measured
anywhere within 13 dB of full power, since Class D amps are near 100%
efficient at full power. Reading further, it seems that they do power
rail switching (a la Class G) to get their claimed high efficiency at
low power output. The big question is of course, "So what?".

The first product on their product listing is the AS2001 50 WPC stereo
amp. Let's assume that at power levels below 1 WPC, that they have
higher efficiency. However, any decent product built with this part
will need a power supply capable of > 100 W, or energy storage capable
of delivering ~ 100 W for some reasonable amount of time. Once you've
done that, who cares whether you can save 0.5 W dissipation when you're
listening really, really quietly?
From: fitlike min on 22 Nov 2009 02:03
On Nov 21, 10:56 pm, "TTman" <someone...(a)ntlworld.com> wrote:
> 100Watts, runs from a 1.5V battery . Yes, that's correct ! So that would be
> a 500AHr. single nicad then, with a 2C charger.
> Its true !http://www.audiumsemi.com/

It quotes peak output power. I switched off then. Only amateurs use
peak power or fraudsters.
Power is defined as average power or instantaneous.

F.
 |  Next  |  Last
Pages: 1 2 3 4 5 6
Prev: day shot to hell
Next: Ping Bil Slowman; The global warming hoax reveiled