by Andrey Kuznetcov
10/06/2004 | 08:20 AM
The range of available external optical drives is rather small today, and your choice becomes even more limited if you need a very compact device – to take it with you on your business or entertainment trips. We already presented to you a miniature combo-drive from ASUS in one of our previous reviews; today we will deal with a newer model.
ASUS has never been scrimpy about accessories to its optical drives. Besides the SCB-2408-D drive proper you receive a quick installation guide, a user manual, a CD with Nero Burning Rom (version 184.108.40.206), and a CD with multimedia software (Media Show, Power Director, AsusDVD). Besides that, the drive’s accessories include two blank discs (CD-R 52x and CD-RW 12x), a leather transportation sheath, a USB cable, a FireWire cable, a power unit with a cable, and three adapters.
Having fumbled through the accessories, let’s now take the hero of this review into our hands. The drive resembles its precursor a lot: it is the same box of silvery aluminum designed like the standard CD box but thicker. There are four round rubber pads on the bottom of the case that make the device steady on the flat and slippery surface of a desk, system case and so on.
There’s also a lever for opening the lid manually there. In the top-right corner of the top of the case there’s a triangular STOP/OPEN button to open the lid up or stop the playback. The PLAY/SKIP button allows starting the playback from the first track when the drive is in the idle mode; when playing an audio CD, this button moves the playback to the next track. The Power-On slider is located at the right side of the drive; next to it, there’s an indicator of the voltage and of the driver’s operational mode. The left side of the case has a hole to plug the power adapter into. The back panel of the case has a headphones socket and a volume control as well as USB and FireWire connectors.
It’s time to say a few words about the speed characteristics of the ASUS SCB-2408-D drive. So, it can burn CD-R media at up to 24x speed and CD-RW discs at up to 10x speed. It reads CDs at up to 24x speed (in the DAE mode, too) and DVDs at 8x. The access time is 100msec for CDs and 120msec for DVDs. The amount of cache memory is 2MB. The drive supports media of the following formats: DVD-ROM, DVD-R/RW, DVD-Video, DVD+R/RW, CD-Audio, CD-ROM, CD-ROM/XA, CD-I, Mixed Mode CD-ROM, Photo CD, CD-Extra, Video CD, CD-Text, DVCD, Bootable CD. The support of two interfaces (USB 2.0 and FireWire) provides the necessary connection flexibility.
The drive can automatically detect a disc unbalance and reduce the read/write speed to ensure a higher quality and a lower level of noise and vibration. Besides that, an exclusive intelligent technology for automatic control over the MP3 playback speed helps to reduce the power consumption and extends the lifecycle of the device. FlextraLink technology is monitoring the status of the drive’s buffer to avoid the buffer underrun error, while FlextraSpeed chooses the optimal burn speed by constantly controlling the medium during the burn process.
The dimensions of the device are 129x16x142mm; its weight is 250 gram. The average retail price of the SCB-2408-D combo-drive is $145.
I used the following programs to check out the driver’s operational characteristics:
The testbed was configured as follows:
The drive was attached to the mainboard’s USB 2.0 port.
The utilities report the driver’s support of C2 errors correction, but don’t mention its ability to process DVD+R/RW media, which is declared by the manufacturer. The drive is regionally protected.
This time I couldn’t test the drive using an original disc and two copies of it, on CD-R and D-RW media – the drive couldn’t read the original disc through, reporting numerous errors.
Judging by the two diagrams, I’d say that the drive processes CD-R media better than CD-RW discs as it has better WinMark results, a higher data-transfer rate and a lower access time with CD-Rs.
To carry out the basic CD tests I used a molded CD enclosed with a computer magazine, a 700MB CD-R and CD-RW data discs written with the test utility itself, a likewise-prepared 800MB CD-R and an Audio CD. Thus, my tests will show us how the drive processes the most popular compact-disc formats.
The SCB-2408-D reaches the declared read speed without any troubles on four discs out of five. The 800MB disc poises a certain problem for it, though, and the drive only accelerates to about 17x speed. The access time complies with the device’s specification. I don’t post the results of the disc load test, since this operation is done manually with devices of that type. The high burst rate is indicative of the drive’s using data caching techniques.
Now let’s perform some tests with DVD media. I used five discs again: a Video DVD and its copies on DVD-R (Digitex), DVD-RW (TDK), DVD+R (Fujifilm) and DVD+RW (Verbatim) discs.
The drive could only reach its declared speed with three out of five DVD discs. Of course, the lowest speeds were with the rewritable media. By the way, in spite of what the informational utilities say, the SCB-2408-D successfully handles DVD+R/RW media – just like ASUS, its manufacturer, claims. The measured access time exceeded the specified one.
The Advanced DAE Quality Test will help us determine the hardware properties of the drive pertinent to the quality of audio copies you make with it. I used two special CD-R discs Nero CD-DVD Speed had prepared. One disc was normal, the other had defects of the surface which every long-used disc has.
The first screenshot tells us that the drive provides the maximum quality (no read errors at all) when working with good discs. However, I can’t say it’s perfect for making ideal audio copies since the big offset value prevents the driver from positioning exactly over the necessary spot of the audio CD. The inability of the drive to read the lead-in and lead-out information has a negative effect on making precise audio copies, too.
The second screenshot shows you the drive’s handling an audio disc with scratches on the surface. The average read speed degenerated by a half, and there appear read errors, but the overall quality score remained the same, i.e. the maximum possible. This signifies that the drive is capable of processing errors effectively.
I used the Advanced DAE Error Correction Test for an in-depth examination of the drive’s ability to process C2 errors when extracting audio tracks. Nero CD-DVD Speed itself created a test disc – with scratches on the surface. The program then determines how many C2 errors should be found at all, and how many of them the drive did find. Basing on that, the quality score and the C2 accuracy parameters are calculated, which reflect the efficiency of the hardware error correction mechanism of that optical drive.
The screenshots above suggest that the SCB-2408-D is quite efficient at correcting errors. It missed few C2 errors, approaching closely the maximum possible result.
It’s nice to be able to burn more information on a disc than that disc is rated for. I used four CD-R discs to estimate the drive’s skills at overburning. Three discs were 700MB (Fujifilm 52x, Digitex 40x and TDK 48x), and one was 800MB (TDK 40x). The maximum possible length of the recording in the emulation mode was set up to 99:57.74 in the test program.
The results you see in the screenshots do not impress much in three cases out of four – only two or three minutes above the norm. But when working with the Digitex disc, the SCB-2408-D reached the maximum result, burning the entire disc through without any errors until the set-up limit. So, the overburning capabilities of the drive depend on the media you use – keep this fact in mind.
CloneCD is used to determine the time it takes to copy a legal CD with the Cossacks game into an image file on the hard disk drive and then burn it onto a CD-RW Digitex 4-12x.
The results don’t actually require my comments. Anyway, note that the read speed is almost twice lower than the write speed.
To evaluate the CD-R burn mechanism, I carried out the test of burning four blanks in the simulation mode. The discs were the same as I used in the Overburning test.
The drive reached its declared write speed of 24x with all the four discs. The speed had been steadily growing up to that mark and remained constant thereafter.
The CD Quality Check test once again helped us to evaluate the drive’s ability to process low-quality media. To do the check, I used a molded data CD with a mechanically damaged surface and a CD-RW disc written with CloneCD.
The drive found quite a lot of C2 errors in the first disc which the disc really had. The absolute lack of errors on the CD-RW disc suggests that the drive is very good at burning such media.
The undisputable advantages of the ASUS SCB-2408-D drive are its compact size, small weight, support of two interfaces, ability to work with DVD media of the two competing formats, and efficiency at processing C2 errors.
On the downside, there is the too high offset value. Even with the highest quality score in the audio extraction test, the high offset may negatively tell on the quality of the audio copies you make with this drive. The speed characteristics of the SCB-2408-D combo-drive are rather low for it to compete with modern full-size external and internal devices of that class, so it targets specifically users who need a very compact optical drive. The rather high price of the device also differentiates it from other models, making it a not very optimal choice unless you are really interested in getting the smallest optical combo-drive possible.