Slow to load

I have a website that has become very slow to load over the last couple of weeks and cannot decide if it is a website or server issue.
I have removed the unused and recently installed plug-ins without noticeable improvement. I have also tried uploading through proxy servers with equally dire results.
Before I changed hosts I though i would ask those here to checkout upload times and suggest where the problem may lie.
I have other none WordPress websites on other hosts that upload acceptably quickly.