The Emotive Audio Sira linestage uses a single 5687 for the gain (plus a lot of other tubes for voltage regulation and current sources), and the Emotive Vita amps use a pair of 5687s for input and driver stages.
The YS Audio A2 linestage uses 5687s. I haven't found anything better than the Tung-Sol D-getters here, although they are a bit tipped up...but other 5687 types I've tried in the A2-SE make my system sound like a giant AM radio.
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