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Hammerfall DSP System
Hans Ippel about the Compaq Armada E500 Thanks for the technical information about audio notebooks on the RME website. I'm looking forward to use the coming Hammerfall DSP packages to make sound recordings on my Compaq Armada E500 notebook. DVD-ready recordings finally become a reality with the DSP series, especially for sound-recording amateurs and small studios doing location recordings. In my case mostly two-track (and hopefully in future 6-channel surround) recordings of classical music and other live concerts. Maybe I can give a positive contribution to the test of the E500 listed in the table of recommended and not-recommended notebook computers for use in audio applications. See this as a user report. I'm not responsible for possible damage caused by the following suggestions, but I feel that it may help a lot people struggling to get most out of their newly bought Compaq notebooks. All suggestions are tried out first-hand on my own E500 and are as such carefully analyzed. First to show you my current E500 setup (bought in December 2000):
Other equipment (for the people interested):
Windows98SE upgrade and fine-tuning
of the Compaq E500: My E500 notebook is further fine-tuned for doing audio tasks, using the recommended Windows-tricks already mentioned on the RME and IQS websites. Most critical item is that DMA on the hard disk cannot be enabled in the Compaq setup, leading to significantly reduced disk throughput and noticeable audio glitching. After the Windows98SE upgrade the DMA option becomes available to be enabled and the sluggish behavior disappears. Sustained transfer rates for the disk now become 12.5 and 10.5 Mbyte/sec for resp. read and write mode on a clean partition, both measured with the SAW HDspeed program. The values are quite respectable for a smaller 4200 rpm 2.5" IBM hard disk. The Norton Utilities 2001 system benchmark of the computer running at 600 MHz now measures a value of 320.2, close to the value for a typical P-III 600 MHz desktop computer. In the original installation the transfer rates were something like 1.5-2.0 Mbyte/sec (!) with heavy glitching occurring whenever audio data was written in bursts to the hard disk. RME has reported the same thing for their computer test, the E500 test model runs at crawling speed, despite being equipped with a 1 GHz Pentium processor. It is obvious that the factory settings, together with the standard 64 Mbyte (or nowadays 128 Mbyte) memory, results in an extremely sluggish machine not worth to consider for audio recording, let alone to run office applications. The bottleneck on the speed issue is logical, because almost every computer action runs via a virtual memory disk file where data are moved in and out of swap at very slow (<2 Mbyte/sec) speeds. A faster processor wouldn't help you in that case. User reports however indicate that, after enabling the Windows98 DMA function, it is not possibly anymore to hotswap the CD-rom or DVD reader for a second hard disk. But with bigger and cheaper Firewire hard drives to come, it looks more convenient to add a second, and easy replaced, 80 Gbyte Firewire audiodrive to your notebook computer. Big advantage of FireWire is that you can swap the audio disk containing the recordings to another editing computer within seconds. Transfer of the audio files over 100Mbps ethernet cards looks fast on paper, but in practice it would still take a massive 2 hours to copy a 6-channel 24bit/96kHz multitrack recording of a total size of 8 Gbyte from your notebook to another computer. Windows98 Memory tricks: To maximize the use of the (expensive) notebook memory, the line ConservativeSwapFileUsage=1 is included in the [386enh] section of the Windows system.ini file to emulate Windows95 behavior. This does miracles to Windows98 computers, because the memory manager is forced to consume physical memory first, before consuming the slower virtual memory page file. Although approximately 106 Mbyte of my 320 Mbyte physical memory still remains unavailable to Windows98, once the (fixed) swap file has finally been put into action by the operating system above ca. 65% of memory usage. Nevertheless, the physical memory, with Windows95 emulation switched on, has been more efficiently utilized than without the extra line in the system.ini file. In that case the swapfile is already partially used at startup time under a memory load of a mere 50 Mbyte, necessary for Windows drivers and other startup utilities. This type of memory mismanagement in Windows98 is normal I'm afraid, even with 256 or 320 Mbyte RAM installed (very bad design of Windows98, blame Microsoft). Restoring wrong icons on the desktop view: Note that it also important for the E500 to manually increase the Max Cached Icons string value from zero to some high value. Still don't know for sure if this originates from the Compaq setup, but it caused problems in the correct display of graphic icons linked to Windows-defined file extensions. In my case the cache was standard set to 0, meaning that Windows occasionally freezes, because of a slow graphic refresh of icons and associated links on the desktop view. The higher cache setting adequately solves the icon problems and also prevents the small Windows interruptions, normally disastrous for time-critical audio streams during digital recordings. Before the cache change recordings ran fine using the DATport, except that at the start of the recording and on average once in every 20 minutes a random small dropout in the recorded file occurred. After the change in the Icon settings >90 minute digital recordings over the DATport are now bit-by-bit identical to parallel-made DAT recordings. For details on wrong associated icons see Windows question
Q132668: Battery power vs external power supply: As a last point RME may consider the quality of the included power supply in the technical recommendations on notebooks. For now I recommended the use of battery power for critical audio recordings on notebook computers. E.g. the universal power supply of the Compaq E500 produced a nasty ground loop problem in one particular case, resulting in electrical interference on the mainpower and rattle-hum sounds on connected audio equipment. Quickly plugging in the external power supply adapter into a 240 Volt wall socket seems also dangerous. It happens occasionally that a big blue arc sparks out upon connecting the 240 Volt net cable to the adapter and if you're not careful the chances are pretty high that you electrocute yourself by grabbing the extension cable too close to the adaptor. You don't read THAT in the manual! But all in all, this is not a good sign for the presence of well-designed electronics inside the external power adapter. Big question here: is it useful to look for another, more audiophile oriented (read non-switching) power supply for notebooks ? Build-in ESS Maestro soundcard and tips to reduce ambient noise levels By the way, here is a extra tip to improve ambient noise
levels generated by the E500. To come back to the internal soundcard and the two speakers in the E500. Muting the speakers is also very useful to prevent the inevitable warning beep sounds when the notebook is running low on battery power. The warning beeps are controlled in the BIOS and difficult to circumvent by software. The volume and mute buttons in the mixer applet don't work to make the beep silent, so keep a 3.5 mm miniplug inserted to avoid the nice and loud beep sounds at recital concerts. Low battery indication on the E500 starts as soon as the accu reaches 13% capacity, however you can go down to 3% power reserve before you're seriously have to think about shutting down your computer. A tip here: please calibrate your battery in the Compaq setup first before upgrading the operating system, otherwise I cannot guarantee a correct calculation of the remaining power indication on the E500. Conclusion: In conclusion, the E500 does its job quite well after the software upgrade and applying other tricks. Please blame the Compaq software for poor performance, it's not because of inferior computer peripherals inside. I hope that these observations on the E500 computer may help other people to choose a suitable notebook and to lift the reputation of this particular computer model. The advantages of the Compaq E500 are:
Note that even with a modest 500 or 600 MHz processor running at 100% raw CPU power during two hours, the buildup of excess heath (despite maximum fan speed) can transform your notebook into a suitable device to quickly defrost pizzas on. Be warned to apply 100% CPU power on notebooks with >1 GHz Pentium processors for long extended times without taking actions to limit overheating, e.g. placement of the computer on a aluminum plate/heatsink or by lifting the notebook from the (insulated) table, c.q. putting it on four small blocks to increase airflow underneath the notebook. The big disadvantage of the E500 remains the fact, that by fine-tuning your E500 computer to gain optimum performance, the system becomes quite modified and for that reason the prospect that Compaq still gives warranty on your computer is not high. Whatever the choice of notebook will be, now it is only waiting for the coming revolution in mobile recording with the Hammerfall DSP series of RME. Written on June 12th, 2001 |
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