Cyrus Two would be the best selling and successful British Amp ever made. Definitely, it is the most important product to bring the market standing in its history.
After almost 40 years, it is still a very good amp around. Definitely, very good value for its second hand price.
Cyrus two phone section consists of super matched pair LM394 which is still the best matched pair today.
Here welcomes any idea to maintain and upgrade the Cyrus Two and its Power Supply to improve its performance to race with today's best amp.
1. Replace the aged E-cap
2. Replace of coupling cap for better performance
3. Replace low value and better feedback resistor
with higher quality resistor.
4. Replace the important resistors in RIAA section
the best quality type
However, a lot of component and design is still very good like the Holden & Fisher...