Solo Factory Upgrade

Do you own an original Solo headphone amplifier?

Great news! The new Solo Ultra-Linear Diamond Edition board fits! We can upgrade any Solo produced since mid 2004 to flagship status! DIY enthusiast? No problem! You can buy the board and fit it yourself,

Graham Slee have made many great improvements to the Solo sound over the years, none more so than Graham Slee's innovative development of our Ultra-Linear voltage amp technology - all the good sounding things valves do without actually using them! Then late 2011 the breakthrough came - he got the background noise (hiss) right down to -95dB (that's around -105dB "A" weighted) making it much better for In Ear Monitor users. The Diamond Edition version is nicely rounded off by it's improved output current delivery, meaning it will make even the most difficult to drive headphones sound better.

We always look after our customers and what better way to add to our service than making the latest developments available to you for a lot less than having to buy a brand new Solo Ultra-Linear Diamond Edition?

Don't forget you won't appreciate the full performance of the Solo Ultra-Linear Diamond Edition headphone amplifier without our PSU1 power supply, so if you haven't already upgraded to the PSU1, now's the time!