As you know, regular German type D visas are not restricted to Germany but also allow the holder to visit another Schengen country for up to 90 days in any 180-day period (some visas or other documents restricted to a single country do however exist, e.g. for asylum seekers).
It's not required to enter the Schengen area through Germany either. Article 5 of the Schengen Borders Code even includes several provisions explicitly referring to this possibility (my emphasis):
- For intended stays on the territory of the Member States of a duration of no more than 90 days in any 180-day period, which entails considering the 180-day period preceding each day of stay, the entry conditions for third-country nationals shall be the following:
(b) they are in possession of a valid visa, if required pursuant to Council Regulation (EC) No 539/2001 of 15 March 2001 listing the third countries whose nationals must be in possession of visas when crossing the external borders and those whose nationals are exempt from that requirement ( 18 ), except where they hold a valid residence permit or a valid long-stay visa;
So you can cross any external border, your long-stay visa can replace the Schengen visa you would otherwise need.
Furthermore, the regulation also includes this:
- By way of derogation from paragraph 1:
(a) third-country nationals who do not fulfil all the conditions laid down in paragraph 1 but who hold a residence permit or a long-stay visa shall be authorised to enter the territory of the other Member States for transit purposes so that they may reach the territory of the Member State which issued the residence permit or the long-stay visa, unless their names are on the national list of alerts of the Member State whose external borders they are seeking to cross and the alert is accompanied by instructions to refuse entry or transit;
This means that even if you do not meet the usual conditions for a visit to the Schengen area (e.g. you can't prove you have enough money or health insurance), you should at least be allowed to transit in Amsterdam.
Note that the visa must however be valid so you have to check if the period of validity on the visa sticker itself allows you to enter early.
Finally, some countries (don't know about Germany) require some long-stay visa holders, including students, to complete some formalities (e.g. medical check-up or some form of registration) within a specified time of entering. Presumably the delay runs from the date on your entry stamp. To the extent that it's the case in Germany, it would mean that you have one week less to take care of that.