The DSP on the Tascam is pretty basic. I guess it would be fine for adding some performance 'verb, But I tend to stay away from it. I have top-notch digital fx from the TC Konnekt unit. The 7000 sports a single knob for headphones and master vol. If you switch it to control just headphones, your master vol. goes to unity. Not ideal, but hardly a major problem if you are careful. So I don't keep headphones plugged in unless I'm actually using them - both vols. stay under the knob. Finally, line going through the preamps is hardly a major deal breaker. I doubt if anyone can tell the difference without turning the vol. up to ridiculous amounts on a great system. Ideally, again, you'd want separate ins, but there is no practical difference. I plug my preamps (Warm, RND, and other transformer units) and synths through the line ins and it sounds excellent.
As to answer my own question as to why the price drop, I imagine Tascam is making some money even priced as is. It is about right when you consider other "Premium" interfaces start about $600 for the extra features - ADAT, monitoring control, inserts. The RME is $700. I doubt if the 7000 is getting new drivers. Craig says the new multi-input Tascams are getting in-house drivers while the 7000 had outside ones. But if you just need the sound quality, you are covered. I'm very happy w/ it.
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