Computer CDROMs

[fmak]

There is very little information on computer CD and DVD ROMs on which to base AUDIO performance judgements. The review in the computer web sites go into great depths on seek times and so on but these bear no relationship to parameters like clock accurracy, jitter, ability to read discs properly, error correction in CDA and so on. There is absolutely nothing on how good the SPDIF outs are. Instead, even audio conscious sound card manufacturers seem to confuse SPDIF with CDROM audio - again virtually no info on performance. The drive manufacturers just go on about read accurracy and don't even supply properly shielded 75R cables!

I have taken some time and effort to make a quiet (50dBC) computer with Terratec 2496 card with NO SRC, separated from the Video card by 4 slots and shielded . The IRQ is also separated from the video card but there is no way to give it its own IRQ like the bloody keyboard and mouse! It has proper 75R externally routed connections and ability to read from three drives. The things sounds very good and measures well for a computer system but no where matches my outboard DACs in sound quality.

1. Creative 52X audio(?) ROM sounds best but clock accurracy is poor and my Assemblage D2D will not lock into the narrow band PLL. This drive will read the CD layer of most, but not all SACDs.

2. Pioneer DVD 106S ROM which sounds worst and which will NOT read the CD layers of SACDs. The things just spins round at high speed.

3. TEAC 540 EK CD-RW which reads everthing properly; has accurate clock; and sounds OK.

If the same level of disinformation apply to those pros who use CDROMs to edit/burn discs, then good luck to the industry.

NO hifi enthusiast will buy audio gear without proper specs and review; yet computer audio seems to be lost in the fantasy world of high speed processors, burners and fancy pro software with fancy names for 'unwanted' functions.

What do others think and can they point to sources of informed opinion on CDROMs, sound cards and software?

[SkinnyBoy]

I don't think CDroms would be that good, cos they run off a switchmode powersupply.. if you made a non switchmode supply (using a transformer and regulators) the quality would probably be better...

[fmak]

[QUOTE]Originally posted by SkinnyBoy
[B]I don't think CDroms would be that good, cos they run off a switchmode powersupply.. if you made a non switchmode supply (using a transformer and regulators) the quality would probably be better...
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DVD players mostly use swm power supplies. There is no reson why a CDROM can't perform well on such. My hq power supply has only about 3-4 mV of wide band noise.

What is needed is transparency in what these computer hardware and software guys are doing.