Altis DAP Reference Bitstream Decoder

I don't have any experience with this unit but here is what everything on the front panel means:
44.1 SPS
48.0 SPS
These are both sampling rates, 44.1 is the sampling rate of regular redbook cd, 48.0 is the sampling rate of dat (digital audio tape) machines. If you only use cd's you'll always see the 44.1 light lit up.
Sync
Making a bit of a guess here, but I'd guess that means the dac has a good connection to the transport, they're in "sync".
De-emphasis
In the early days of cd, some recordings were pre-emphasized. I don't know exactly what this means, but if you play one of these discs through your dac, it will automatically de-emphasize the disc and that light will be lit. Those are all pretty standard things to find on the front of a dac. Others may have a different take than me, but I'm pretty sure I'm dead on. In any case, enjoy your new dac!

Great answer. Preemphasis is the process whereby certain frequencies are boosted and others are cut, just as happens with LPs. Deemphasis then puts the playback through an inverse filter to restore the flat frequency response. In LPs the filter curve is the famous RIAA equalization curve ... I have no idea what was used for CDs, other than it's not widely used any more.

Ingrese Hello zepolrotciv

Today in 2020, a friend is selling me for $ 1,000 an Altis DAP Reference (like the one you showed you in this post in 2003). Could you please help me? Do you think it is a good investment? Tell me what you think about this DAP? My CD is an Audio Research CD3.

Thanks