J20 and J20H Upgrades

I love the feel and tone of the J20, but the build quality, noise floor, and reliability can be vastly improved.





If your J20 Mains Transformer has failed, I can help.

I take the excellent-sounding J20 and make it much, much better. Now you can confidently use the amplifier night after night without worry.

The Mods

1 - The stock ‘forbon’ circuit board, known for becoming conductive over time, is removed, and a new Keystone eyelet board made from FR4 is installed. F&T and Sprague electrolytics, MF and MO resistors, and quality tone capacitors are used to improve the noise floor of the amplifier.



2 - A HT fuse is fitted, along with a safety resistor so that the amplifier can not hold a lethal charge when switched off



3 - The grounding scheme is vastly improved, no more hum and buzz



4 - The stock CTS potentiometers are replaced with Bourns units, including the switched TONE pot.


5 - A lead dress improvement is carried out to reduce unwanted noise

6 - The Mains Transformer is replaced with a custom-wound, UK-made unit, allowing the removal of the noisy cooling fan whilst retaining the sag and bloom characteristics that you love



7 - The Mains wiring is brought up to all current safety regulations, ensuring complete compliance with the law




8 - Screen Grid Stoppers are added to help prolong the life of the output valves, along with setting the bias for optimal tone and feel

Got a J20H? I can carry out the same upgrades as above, but the main transformer doesn’t need replacing, although our unit performs better!

J20 - £550 inc VAT
J20H - £450 inc VAT

12-month parts and labour guarantee on all Rift work on these amps. Prices above do NOT include valves if required.

Please call 01280 472707 or e-mail repairs@riftamps.com to arrange improving your amp to the standard it deserves!