CD to iPod Solution 6.4.2 Online Manual

Frequently Asked Questions

Q: What's an ASPI manager, and how do I know if I have one?
A: ASPI is an interface created by Adaptec, and is used by CD to iPod Solution to access the CD-ROM hardware. Windows 95 comes with the ASPI manager pre-installed, while NT does not. To tell if you have an ASPI manager installed, look for a file called WNASPI32.DLL in your Windows system directory (c:windowssystem or c:winntsystem32 are common locations). For NT, it is usually supplied by the manufacturer of your SCSI adapter or devices -- unfortunately, not usually supplied for IDE devices under NT. Some ATAPI CD-R and CD-RW devices do however supply the ASPI manager, specifically so that it can interface with the CD-R and CD-RW burning software.


Q: Does CD to iPod Solution work without an ASPI manager?
A: Under Windows NT (SP 4+) and Windows 2000, CD to iPod Solution can use the SCSI pass through interface to gain low-level access to the CD unit. The preferred method is still via the ASPI manager, but since neither Windows 2000 nor NT has a built-in ASPI manager, this method is provided as a fall-back.


Q: What is "jitter", and just how does "jitter correction" work?
A: "Jitter" is a term used for the inherent uncertaintly in most CD-rom units, which is caused by the way audio is stored on a CD. Although one logical block on a CD takes up 2352 bytes, the amount of data stored in the block varies. For a data block, 2052 bytes are actual data, and the remaining 300 bytes are information used to accurately find the block. For audio, however, all 2352 bytes contain audio data -- there is no positioning information returned in the block read. When CDs first came out, they were used for audio, and it didn't matter if a CD player got within +/- 1/75 of a second of the intended start position. After it started, as long as the player kept reading, it could accurately read the data -- the problem only came about when initially seeking the start position.

"Jitter correction" is the process of trying to compensate for "jitter" in software. Generally, it involves using overlapping reads, and attempting to match the end of one read with the beginning of the next, so that there are no gaps in the data read. These gaps cause clicks and pops in the resulting WAV or MP3 file produced. For instance, the program might begin reading a track at block 1000 and read 27 blocks total. On the next read, it would issue a read command starting at 1024, and would try to match the end of the first read in the beginning of the second read. Once it finds a match, it would cut off the beginning of the second read, and use only the part after the match. In this way, you can eliminate the clicks and pops.

CD to iPod Solution has an additional, more sophisticated mode for jitter correction. It will attempt to issue many read commands quickly and buffer the output. When ripping with CD to iPod Solution, you can see this happening in the "Read buffer" gauge on the rip dialog -- it will attempt to buffer as much as it can quickly, and then wait for the encoder to process it. When the buffer is almost empty, it starts reading again. It only performs jitter correction after an error is reported by the CD unit. Most drives will read audio correctly as long as the drive doesn't stop reading for too long, and read commands are issued sequentially, ie. the next read starts immediately where the last read left off. Using this method results in a vast speed improvement over brute-force jitter correction.

Most times, an LP or music cassette also contains multiple separated tracks, so that you can easily digitize each track one by one, or you can use the Audio Editor to separate tracks if you record an entire LP or cassette side at once.


Q: I can't seem to rip any tracks at all. Help!
A: Try resetting the jitter correction values to their defaults in the CD Options dialong (click on the "Reset" button). If that doesn't work, In the CD Options dialog, try using the "Autodetect" read algorithm. If it still doesn't work, try the others individually. If none of this helps, send an email to support@mcfunsoft.com with the make and model of your CD rom, operating system (Win95/98/NT,2000), whether it's a SCSI, ATAPI, CD-R, etc. and a description of the problem. It's also possible that your drive simply doesn't support digital audio extraction -- while most SCSI drives support digital audio extraction, not all IDE drives do.


Q: I can rip, but it seems to rip very slowly.
A: Try checking the "On Error" jitter correction in the "CD Options" page. This mode is faster than the "Always" setting, and should produce results comparable to "Always".


Q: How can I tell if my CD supports digital audio extraction?
A: If CD to iPod Solution doesn't seem to work with your CD, try a different program -- you can find many shareware and freeware programs at www.mcfunsoft.com.


Q: I'm still getting clicks and pops in the ripped tracks. What can I do?
A: Go to the CD Options page by selecting the Options->CD Settings menu item. Try using the "Always" setting for jitter correction -- this setting will attempt to correct inaccuracies in the positioning of the read regardless of whether the CD reported an error or not. If you receive errors, try increasing the overlap a little; this will increase the size of the buffer that is used to align the read, and so increases the chances for successful alignment.