Reference Transports: An overall perspective

Mike, I believe Lktak is referring to what nearly all Universal players use. Models like the Denon 3910 and many other Universal players read at something like 10x rate and buffer to SRAM, then reclock out. Some carry this buffering to redbook CD as well. In theory, if your error correction software is infallible and your reclocking extremely precise, this should result in a perfect bitstream. Questions are: 1.) is adaptive error correction good enough. 2.) what influence does mechanical vibration have on (1.) and on the overall performance of the player/transport. I wish I could answer these... I cannot, but I too have heard significant and very meaningful differences among transports.

thanks for the info...i wasnt aware the universals did this (this sparked my interest, i remember the chord dac64 & the tube technology fusion)...

were there any other devices (internal or external) are available beside the genesis lens ?

I´d like to add another one Barclay X-1

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Questions are: 1.) is adaptive error correction good enough. 2.) what influence does mechanical vibration have on (1.) and on the overall performance of the player/transport. I wish I could answer these... I cannot, but I too have heard significant and very meaningful differences among transports.
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Answers:
1. Error correction is designed to fix bit errors. These are gross errors. Ever drive your car thru a bump and your CD player skips? Error correction is designed (together with buffering) to fix these types of problems. If you plan to listen to your music while thumping the player with a hammer, then I would be concerned about how good the error correction is.
2. Mechanical vibration is answered in (1) above.

The transport has no effect on the signal data if it is read out to a storage device such as RAM prior to further processing.

I am not referring to any specific CD/DVD player. In our hypothetical CD/DVD player, the entire song can be uploaded to RAM (i.e. computer memory). This is very inexpensive. Once the song is in RAM which is a digital circuit, it can be read out and processed by the other digital circuits of the CD/DVD player. These circuits perform error correction decoding and filtering. These are typical circuits in any CD/DVD player.
The key point here is that once the song has been uploaded to RAM, the transport is no longer part of the signal path. It is effectively non-existent. You can think of an Ipod Nano as a CD/DVD player which has the song loaded into RAM. Of course the loading of this data is performed from a PC and not a transport.
Once the digital signal has been processed by the digital circuits, this signal has to pass thru a D/A converter. The quality of the D/A converter as well as the clock which clocks the D/A converter can effect the sound quality. If the clock is sufficiently jittery, you will hear this.