Yes. They will not sound the same as the originals. Different engineers & better equipment. They are getting more info from the source tapes and are being able to transfer that info to the master lacquer. These improvements change the sound quality for good or bad enough that they will not sound the same. Don't forget even though it does not seem it all the time, better quality control and a lot less pressings (2,000,000 or more to now 10,000) will also change the sound.
We also hear differences in the original releases. Records pressed from the first pressing sound differant than from say the 5th pressing of the same record pressed by the same company back in the day. Pressings also differ from country to country. Why pay more for a British release of a Beatles album if it sounded the same as an American release or why even want one for that matter. I think all records other than original first pressing from the country of origin ARE reissues and sound different. That's why people pay more money for an original pressing than even a second pressing of the same album - again, they sound different. IMHO.
We also hear differences in the original releases. Records pressed from the first pressing sound differant than from say the 5th pressing of the same record pressed by the same company back in the day. Pressings also differ from country to country. Why pay more for a British release of a Beatles album if it sounded the same as an American release or why even want one for that matter. I think all records other than original first pressing from the country of origin ARE reissues and sound different. That's why people pay more money for an original pressing than even a second pressing of the same album - again, they sound different. IMHO.