BLER measurement results of the discs recorded on the testing drives

Inspite of the fact that there are a lot of information on CD-R and CD-RW drives in the Net, nobody still managed to carry out the testing of CD-R devices in terms of record quality. For it, one need to carry out complex tests on expensive equipment (usually only the manufacturers of the discs and drives possess it). 

One of the most important criteria of recorded CD quality assessment is BLER.

BLER - BLock Error Rate, is a parameter which shows how many reading errors from the surface per second are corrected by the block CRC.

Unfortunately, there are no widely available devices, which allow a user to measure this parameter. But we were lucky to get such equipment. 

The device consists of a developed Casio CD-player and a Chinese  multimeter-cymometer.

The principle of working of the device is quite simple - after loading the disc, it starts being read for the purpose to detect possible errors, and the multimeter-cymometer will show you a BLER parameter in figures.

The device doesn't show an absolute value, since it hasn't been calibrated. But in order to compare the record quality of our discs we need only the figures of the current testing. For more information on the devices for disc quality measurement see here.

Guided by my own experience, here I show you the following picture of the quality of the discs recorded on TEAC CD-R56S
 

The first from the end were "unconquerable" BTC and all variants of Ritek products. In their case the BLER were rare less than 100, and even 200 on the disc's edge. Although the standard of "Red Book" allows BLER 220 (so, it's not so frightening for the majority).
 

The results prove the leadership of Plextor products as for record quality for any discs and under any conditions. Note quite good results for Samsung SW-208B and NEC NR-7500A drives when recording the discs. At the same time, Philips Professional discs turned to be of poor quality, when recorded with these drives.

For the Mitsumi CR 4804 TE drive we indicated the maximum value in parentheses. None of the other discs showed anything similar. Noteworthy are bad results of Ricoh RW7120A recorder, especially bearing in mind that it had to record Philips Silver disc. Quite high BLER factor for Taiyo Yuden products doesn't mean very good of this drive. Philips Professional disc had nearly ideal results, when recorded on TEAC CD-W54EK.

Putting inside the disc recorded with Yamaha drive and looking at the results I doubted whether the device worked good. Then I checked some other discs with the obtained results earlier - the device performed well. Then I played the disc one more. 100... No one drive had anything alike. BLER factor for Philips Professional disc leaves no hope. Note, that we didn't notice such thing with Yamaha CRW8824E-NB recorder. A later model shows the results corresponding to the average level.

The complexity of Data CD testing is that the recorded information represent a single unbroken track for the device. That's why it's quite difficult to set the laser to the center or to the end of the disc. Musical CDs don't face this problem. You can position the laser on any spot of the disc. Audiotracks were recorded on the discs from Sony CDQ-74CN (Taiyo Yuden). Unfortunately, we managed to get the BLER device when the most recorders had been tested, and audio discs were recorded not with all drives. It made us to look again for drives wherever we could do it. Fortunately, we managed to fetch all but 3 recorders, so we wrote Audio CDs at the maximum speed. Yes, we know that it's better to set 2x for the optimal quality, but we purposed another aim: it's to position the laser accurately on the definite track: in the beginning, in the center or in the end.

The device's author told me that the modern discs are better to record at the maximum speed. He explains it that the laser has the highest power at the maximum speed, what tells positively upon recording quality of the matrices intended for such speeds.

The disc recorded on the drive from Mitsumi had not any leaps which were noticed on CD-R Philips Professional. Again, we can "admire" the high BLER factor of the Yamaha CRW8424E drive. As for Plextor recorders… we can see it yourselves ;) 

Perfect BLER results were obtained on the matrix recorded on TEAC CD-W54EK. In all other respects, you can see the same quality gradation of the recorded discs as with the discs recorded as Data CD.  

Conclusion 

The leaders in terms of recorded discs quality are the drives from Plextor and TEAC CD-W54EK. Though we should notice that the disc recorded with Teac has rather average BLER result. The next one goes NEC NR-7500A. A positive impression was worsen by middling results of Philips disc recorded with this drive, the BLER factor for the technological disc and Sony disc is excellent, however. BLER factor leaps, when reading the discs from Philips recorded with the Mitsumi CR 4804 TE, prove an unstability of the recording on this type of discs. But bearing in mind that for the technological disc the result was good, we might have just a defective matrix.

The lowest result was shown by Yamaha CRW8424E drive. The drives from Yamaha showed no  good results for all discs. Creative drive didn't outscore others as well. Almost all discs had the BLER factor higher than the average results of the matrices recorded with the other drives. 

For all discs we can observe the tendency of the quality worsening to the end of the disc. The best results in this section were achieved by the drives from Plextor (both models), TEAC CD-W54EK, Ricoh MP7080A-DP and NEC NR-7500A.

For more information on the drives see the corresponding review parts (1 2 3)