(Last updated 10/19/2005)October 19, 2005: We have a new champion!
Transcend's new 4 GB SD card, mounted in a Dell X50v, is capable of writing data
at more than 2.4 MB/second. This should easily allow recording at rates
of 24/192 in PDAs with a sufficiently fast CPU.
Following closely behind the Transcend 4 GB card is ATP's 2 GB SD
card.
Our PDAudio high resolution digital audio recording system
can be hosted on PDAs, laptop and desktop PCs. On desktop and laptop
PCs you'd typically record to the internal hard disk. On PDAs though,
you'd record to a variety of mass storage devices including:
- Compact Flash (CF) memory cards
- Compact Flash hard drives ("microdrives")
- PC Card (PCMCIA) hard drives
- Secure Digital (SD) memory cards
- External hard drives with PC Card interfaces
The 624 and 400 MHz XScale CPUs used in the current generation of
PocketPC PDAs, and the 206 Mhz StrongArm CPUs used in the previous
generation, are capable of recording in stereo (two channels) at up to
24-bit/96 Kilosample-per-second. Some memory cards however, can't
support the 576 kilobytes-per-second data write rate necessary for 24/96
recording.
We've found that while some cards are fast enough to support sustained
recording at 24-bit/96 Kilosample-per-second, some can only sustain
24/48, some can only sustain 16/44.1 and some can't sustain even
16/44.1.
To help our customers select the right storage media for their needs,
using SPB Software's excellent Benchmark program (www.softspb.com/products/benchmark/index.html)
we and our customers compiled the following performance measurements.
You can help us to add information to this page. Please download a copy of
SPB Benchmark, run it on your PDA and memory card, and email a copy of
Benchmark's XML fle to: moskowit@core-sound.com .
Transcend, FAT16/64 KB clusters
(Dell Axim X50v) |
4 GB |
2425 |
3615 |
SanDisk standard, FAT16/64 KB clusters
(Dell Axim X50v) |
2 GB |
1599 |
3051 |
SanDisk standard, FAT16/64 KB clusters
(HP iPAQ h5500-series) |
2 GB |
726 |
1103 |
ATP, FAT16/64 KB clusters
(Dell Axim X50v) |
2 GB |
2114 |
2695 |
Lexar, FAT16/64 KB clusters
(HP h5550) |
1 GB |
800 |
1382 |
SanDisk, FAT16/64 KB clusters
(Dell Axim X50v) |
1 GB |
1023 |
2007 |
SanDisk, FAT32/64 KB clusters
(Dell Axim X50v) |
1 GB |
924 |
1910 |
SanDisk, 64 KB clusters
(HP h2200-series) |
1 GB |
1007 |
1326 |
SanDisk, 64 KB clusters
(HP h5100-series) |
1 GB |
836 |
1330 |
SanDisk, 16 KB clusters
(HP h2200-series) |
1 GB |
248 |
702 |
| Transcend 45x |
512 MB |
564 |
792 |
Panasonic
(Toshiba e750/e755) |
256 MB |
228 |
1143 |
Panasonic
(HP h2210/2215) |
256 MB |
56.9 |
327 |
Panasonic
(HP h3800-series, PPC2002) |
256 MB |
58.8 |
366 |
SanDisk
(HP h2210/2215) |
256 MB |
7.68 |
112 |
SanDisk standard, FAT16/64 KB clusters
(iPAQ h5550) |
4 GB |
1000 |
1154 |
SanDisk standard, FAT32/64 KB clusters
(iPAQ h5550) |
4 GB |
1029 |
1171 |
Transcend 45X, FAT16/64 KB clusters
(Dell X50v) |
4 GB |
1246 |
1955 |
Transcend 45X
(HP h2210/2215) |
4 GB |
1001 (formatted 32K clusters) |
1273 (formatted 32K clusters) |
Lexar WA 40X
(HP h2210/2215) |
4 GB |
458 (formatted 32K clusters) |
660 (formatted 32K clusters) |
SanDisk Standard
(HP h2210/2215) |
2 GB |
350 |
579 |
SanDisk Standard
(HP h3800-series/WM2003) |
2 GB |
491
(formatted 8k clusters)
to 691
(formatted 32k clusters) |
814
(formatted 8k clusters)
to 983
(formatted 32k clusters) |
SanDisk Ultra II
(HP h2210/2215) |
1 GB |
674 to 743 |
1100 to 1193 |
SanDisk Ultra II
(HP h5500-series) |
1 GB |
597 |
1060 |
SanDisk Standard
(HP h2210/2215) |
1 GB |
459 |
862 |
SanDisk Standard
(HP h3800-series/WM2003) |
1 GB |
640 |
990 |
Lexar Pro 80X WA
(HP hx4700, FAT16 with 64 KB clusters) |
1 GB |
715 |
698 |
Lexar 40x WA
(HP h5550/5555) |
1 GB |
205 |
542 |
Smart Modular Technologies
(HP h5550/5555) |
1 GB |
143 |
418 |
SanDisk
(HP 5000-series) |
512 MB |
112 |
534 |
Viking
(HP 2200-series) |
256 MB |
292 |
961 |
Hitachi Microdrive, 64 KB Clusters
(HP 5100-series) |
4 GB |
214 |
718 |
Hitachi Microdrive
(HP 5100-series) |
4 GB |
91.3 |
599 |
Hitachi Microdrive
(HP 3800-series/WM2003) |
4 GB |
204 |
652 |
MagicStor 2.2GB
(HP 3800-series) |
2.2 GB |
54.8 |
546 |
Toshiba/Kingston/CMS
(HP h3800-series/WM2003) |
5 GB |
57.2 to 193 |
531 to 611 |
Kingston
(HP 5000-series) |
5 GB w/4 KB Clusters |
128 |
720 |
Kingston
(HP 5000-series) |
5 GB w/32 KB Clusters |
229 |
734 |
Addonics ExDrive/IBM TravelStar 40 GB (40GNX, 5400 RPM), 32 KB Clusters
(HP 5100-series with WM2003) |
40 GB |
1688*1 |
1678*1 |
Addonics ExDrive/IBM TravelStar 20 GB, 4 KB Clusters
(HP 3800-series with WM2003) |
20 GB |
810 |
1217 |
Addonics ExDrive/IBM TravelStar 20 GB, 32 KB Clusters
(HP 3800-series with WM2003) |
20 GB |
1069 |
1281 |
(All benchmark results are +/- 20 KB/s)
Pay attention to the memory card and the PDA.
It's important to note that some PDAs have very slow SD memory card
interfaces. For example, the older iPAQ 3800-series SD card interface
is very slow while the 2210/2215 is much faster and the Toshiba e750/755
is faster still.
What results should I look for if I want to record at... ?
24-bit/96 KS/s recording writes 576 KB to disk every second. The second
column of the benchmark results must be greater than 576 KB/s to sustain
24/96 recording. Ideally, if you want to record 24/96 you should choose
a memory card that has benchmark results higher than 576 KB/s. A
benchmark result close to that value may not record reliably.
24-bit/48 KS/s recording writes 288 KB to disk every second. The second
column of the benchmark results must be greater than 288 KB/s to sustain
24/48 recording. Ideally, if you want to record 24/48 you should choose
a memory card that has benchmark results higher than 288 KB/s. A
benchmark result close to that value may not record reliably.
16-bit/44.1 KS/s recording writes 176 KB to disk every second. The second
column of the benchmark results must be greater than 176 KB/s to sustain
16/44.1 recording. Ideally, if you want to record 16/44.1 you should choose
a memory card that has benchmark results higher than 176 KB/s. A
benchmark result close to that value may not record reliably.
In general, to get the highest write rates you should format the storage
card with as large a cluster as you can. A good formatting tool is
SoftWinter's Storage Tools (
www.softwinter.com). It allows clusters as large as 64k.
In general, the FAT16 file system is faster than FAT32.
So for best performance format your storage media to FAT16 and 64 KB
clusters.
*1 -- Despite the 40GNX's terrific speed, we're unable to recommend it
for use with PDAudio because it is unable to sustain the write rates for
more than a few minutes.
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