[quote user="tractorboy"]Hmm... and the answer is... "yes". Or "no". Here's what could happen: you decide to go with single wiring and spend 30 quid on 6 metres of QED. Then, after a few weeks of listening to your system, you start thinking, "but what if...?" And then go and spend 60 quid on 6 metres of QED silver anniversary biwire. Total cost, £90. Personally, I'd buy the biwire from the start and effectively save yourself 30 quid. That kind of saving should help you to justify the expense

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If you decide to bi-wire after single wiring, just buy another set of cable the same as the first - two lots of single wired cable is the same, less a "bit of glue", as a bi-wire cable.
Better still would be to spend a little more, up to the point of being "good enough" but not beyond, on you single run of cable which will probably give you better results now, and then if you add another amp you'll have forgotten about the extra dosh you spent and won't mind doing it again. Maybe!