[Ray Thomas[_2_]]

a lot of talk based around TI chipsets and the right buffer sizes can lead
one away from a potentially more damaging source of audio datastream
non-integrity: IRQ conflicts and resource sharing within computers. Laptops
fare worst apparently, because of their limited re-configurability, but at
least you can identify the source of bottlenecks (and subject prospective
new purchases to a grilling on the demo bench...if your retailer has such ?)
Worth a look...it's clear and to the point:
http://www.mackie.com/support/docume...h_FAQ_no.1.pdf

Ray

[Ray Thomas[_2_]]

"Soundhaspriority" wrote in message
...

"Ray Thomas" wrote in message
...
a lot of talk based around TI chipsets and the right buffer sizes can lead
one away from a potentially more damaging source of audio datastream
non-integrity: IRQ conflicts and resource sharing within computers.
Laptops fare worst apparently, because of their limited
re-configurability, but at least you can identify the source of
bottlenecks (and subject prospective new purchases to a grilling on the
demo bench...if your retailer has such ?)
Worth a look...it's clear and to the point:
http://www.mackie.com/support/docume...h_FAQ_no.1.pdf

Ray

It's good; it's a shame there's no way with usenet to make posts "sticky".
However, readers should supplement their information by searching for
anecdotes that apply to their equipment. And it makes no mention of DPC
Latency Checker, which, I think you told me, you were the first to mention
on this forum.

The advantage of anecdotal information is that it can save the reader from
trying to solve a system for which there is no solution, or missing an
incredibly obscure solution. My personal anecdote, which I was inspired to
try by google search , is that I was able to drop the latency of an old
laptop, a Compal CL-50, to practically nothing, by disabling the "APIC
battery method", which meters the battery.

Bob Morein
(310) 237-6511

Yes the DPC Latency checker is a good one too, I refer to it whenever I make
a change to a device or it's driver...the ACPI battery checker is a nasty
one, I had the same drastic reduction in latency as yourself when I disabled
that one ! Hotkeys can be pretty bad too, especially the Fn + F1 which
gives you the CPU temperature, that one shot my latency up to 8,000-12,000
us when it was on ! Anyway, I just found a USB port sharing my Firewire bus
so I killed off the USB straight away (2 others hanging around which is
plenty for my needs) Best thing about the DPC utility is that you can store
it on a memory stick and run it on any operating laptop in the store without
needing to 'install' it...so theoretically you'd get a pretty good reading
of latency from there before purchase ?

[Ray Thomas[_2_]]

"Soundhaspriority" wrote in message
...
Yes the DPC Latency checker is a good one too, I refer to it whenever I
make a change to a device or it's driver...the ACPI battery checker is a
nasty one, I had the same drastic reduction in latency as yourself when I
disabled that one ! Hotkeys can be pretty bad too, especially the Fn +
F1 which gives you the CPU temperature, that one shot my latency up to
8,000-12,000 us when it was on ! Anyway, I just found a USB port sharing
my Firewire bus so I killed off the USB straight away (2 others hanging
around which is plenty for my needs) Best thing about the DPC utility is
that you can store it on a memory stick and run it on any operating
laptop in the store without needing to 'install' it...so theoretically
you'd get a pretty good reading of latency from there before purchase ?
It's odd that no one has ever posted to this forum something like, "I
tried DPC latency checker on an XXX-brand out of the box, and it was only
YY milliseconds.

Such information would be so valuable to the new purchaser. So far, I have
had one laptop that, with no fiddling, has extremely low latency: an Asus
S5NE subnotebook. There must be others.

Bob Morein
(310) 237-6511

Bob,
That's good to know...I think I'll start going to some of the ex Gov't
surplus auctions, they seem to be turning up older single core laptops all
the time and I'm sure they sell for cheap. Incidentally, do you know what's
a 'good, low figure' for the DPC latency...I seem to be getting a consistent
flat green (or sometimes picket) fenceline on mine....averaging around 200
or else swinging from around 95- 185 but never going into the yellow zone,
so I'm assuming that's ok ?

[Ray Thomas[_2_]]

"Soundhaspriority" wrote in message
...

3. I use Speedstep for enhanced power/performance control. Set power
scheme to "Maximum performance", absolute latency drops to 115 us.

Bob,

Does Speedstep do anything to shut down (or at least slow down) the cooling
fan ? I'm running a Core2Duo Intel laptop, and the fan seems to be on all
the time, with any task beyond idle. I heard of a utility called Notebook
Hardware Control, which I assume functions similarly to SpeedStep...do you
know anything of this ?