[quote name='paul_5' timestamp='1369936588' post='2094747']
I'd say DHA VT1. Might be slightly bigger footprint than you're after but it's WELL worth the size. They're the canine's testicles!
I think they a use 500mA supply, but the 1spot delivers 1700mA, so that shouldn't be a problem.
Newer ones use centre negative, but the older ones use centre positive, this one should see you right...
[url="http://www.davehallamps.co.uk/page55aa.html"]http://www.davehalla...k/page55aa.html[/url]
[/quote]
I havn't checked the link, but given it's a valve pedal i would assume it still uses an AC power supply, rather than DC? If so, you couldn't power this from a One Spot.
EDIT - Checked the link, turns out it does accept DC power which is a first for me, however it prefers 12v to 9v, so would still recommend a separate isolated 12v power supply to power such a pedal.