Re: [LAU] hardware - Intel CPUs

From: david <gnome@email-addr-hidden>
Date: Thu Apr 17 2014 - 23:41:44 EEST

On 04/17/2014 12:13 AM, Gene Heskett wrote:
> On Thursday 17 April 2014 06:09:56 david did opine:
>
>> On 04/16/2014 02:54 AM, Gene Heskett wrote:
>>> On Wednesday 16 April 2014 08:44:15 david did opine:
>>>> On 04/15/2014 03:17 AM, Len Ovens wrote:
>>>>> On Tue, 15 Apr 2014, James Mckernon wrote:
>>>>>> On Mon, Apr 14, 2014 at 2:06 AM, Len Ovens <len@email-addr-hidden>
> wrote:
>>>>>> I would realy like to stay away from having to use a USB or
>>>>>> FW audio IF. In fact I would like to be able to continue to
>>>>>> use my delta 66 for as long as I can before I spend more
>>>>>> money :) The
>>>>>>
>>>>>> Thanks for the useful info in your post. Just to be clear on this
>>>>>> part: are
>>>>>> you saying you don't want to switch to USB/FW solely because you
>>>>>> want to keep using your delta 66, or because you have some
>>>>>> definite preference for
>>>>>> PCIe over USB/FW devices? If the latter, I wonder why?
>>>>>
>>>>> USB in audio is limited. Getting clear USB ports interrupt wise is
>>>>> not easy. Audio can not be on a hub or share it's usb with anything
>>>>> else, but many new MB have no mouse or kb port so the USB is
>>>>> already being used for that much. The real reason though, is
>>>>> latency. With the pci the latency can be 1/4 what it can be in USB
>>>>> or FW. That is the lowest seeting jack for USB or FW is 64/2, but I
>>>>> can run the d66 at 16/2 with no problem on a well tuned system.
>>>>> This does make a difference for live work. I know that 64/2 seems
>>>>> like very good latency (it is) but remember that the card then adds
>>>>> another ms in each direction as well as the stage distances on top
>>>>> of that. That is the time it takes the sound to reach my ear after
>>>>> going through the computer as a processor and then through the air
>>>>> to my ear. Maybe that is still not worth worrying about... but even
>>>>> with 30 feet of cord and no digital delay, I can hear the delay
>>>>> from my playing to the sound reaching my ear.
>>>>
>>>> Interesting. What is the difference between speed of sound in air and
>>>> the speed of electricity through a cable?
>>>
>>> Sound is nominally 720 miles per hour. Rather leisurely IOW.
>>> A perfect cable is C speed, 258 times faster. But cable (coaxial)
>>> actually range in speeds between 66% of C for home usable cables, to
>>> around 98% of C for 9" diameter high power broadcast stuff, C being
>>> 186,272 miles per second in a vacuum. Thats 298,035.2 kilometers per
>>> second for the metric folks here.
>>
>> Then running your sound from stage to backhouse sound board back to
>> stage and hearing it through headphones would give no latency at all.
>
> For an analogue board, small fraction of a millisecond, for a digital
> board, anybodies guess. A/D and D/A's are essentially pretty quick, but I'd
> still put most digital boards above a millisecond.

That's interesting. We're looking into replacing the analog board with a
digital one.

-- 
David W. Jones
gnome@email-addr-hidden
authenticity, honesty, community
http://dancingtreefrog.com
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Received on Fri Apr 18 00:15:04 2014

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