Subject: Re: [linux-audio-dev] Hardware advice please.
From: Paul Davis (pbd_AT_Op.Net)
Date: Tue May 22 2001 - 21:05:49 EEST
>to a new one. I am also intending to buy this new fangeled dream machine
>from RME which will attach to my box via a pcmcia card.
Which is not yet available :)
>So can anyone tell me if 256Mb ram will be enough to record/play say, 32
>stereo tracks at 96mhz and 32 bits/sec with a few ladspa plugins running
>in real time?
Its not a function of memory size as much as disk throughput and CPU
Hz. I can play 32 mono 32 bit (float) tracks on a PII-450 with 148MB
of RAM with disks that provide about 18MB/sec maximum internal
transfer rate. My system isn't sweating too much at that level, but
its definitely working quite hard. These disks would be close to or
over their practical limit for 24 96MHz tracks.
>Also as this card does all the dsp on its own will a 5400rpm ide/atapi
>HDD be enough?
First, i take it that you plan to run Windows on the laptop, since the
"DSP" functionality is entirely based around a Windows app at this
time. I haven't seen enough info on the FPGA programming to know how
easy this will to duplicate for Linux the stuff you've seen on the
website. I would hope all of it, but its hard to tell.
Second, "all the DSP" just means *mixing*. It doesn't cover LADSPA
plugins in any way.
Thirdly, the RPM of the drive is not a good measure of its capacity
for streaming (though its correlated). You need to know the maximum
internal transfer rate. There are IDE/ATA drives out there that can do
33MB/sec which is amazing.
>I also have a pcmcia scsi card to which I could attach a 18GB HDD. If
Again, its not capacity, but maximum internal transfer rate that will
be the determining factor. You also need low seek times as well, which
IDE/ATA drives tend not to offer, and is directly related to disk
RPM. 5400 RPM is probably too slow.
--p
This archive was generated by hypermail 2b28 : Tue May 22 2001 - 23:29:58 EEST