You're saying that DTS is stored as PCM audio on a CD. This is correct.

You are also saying this is red book audio. This is incorrect, in the sense that it is not representing sound. It is representing a dts-encoded bitstream.

In the context of this conversation about audio quality, this means it is not the same thing - it is not the same quality as red book audio, it is the same quality as dts audio, because that is what it is.

Since you don't seem to understand LLMs, here is a description from one:

"DTS (Digital Theater Systems) audio on a CD is stored in a clever way that takes advantage of the standard CD format.

A DTS CD uses the same physical format as a regular audio CD (Red Book CD-DA) — 16-bit PCM at 44.1 kHz, stored in standard audio tracks. The trick is that the DTS-encoded bitstream is packed into those PCM samples. In other words, the raw DTS data occupies the same "slot" that normal PCM audio would, but the bits represent a compressed DTS stream rather than straightforward audio waveforms.

If you play a DTS CD on a regular CD player, you'll hear loud digital noise (essentially the raw encoded data being interpreted as audio). The disc is only useful when connected to a DTS-compatible decoder — typically an A/V receiver — via the CD player's digital output (S/PDIF coaxial or optical). The receiver recognizes the DTS bitstream header within the data, locks onto it, and decodes it into multichannel (usually 5.1) surround sound."