The Onix Melody is an Australian design made in China and runs 6L6 valves or equivalents. It had a pretty decent sound for the money when released in early 2000 and one of its main claims to fame was the use of a stepped attenuator.
Another feature is its use of Russian military paper in oil capacitors (in the green cans in the picture above). These are not bad in terms of sound quality, but can be bettered with a decent audio grade capacitor. So, after discussion with the owner, we agreed we would upgrade the cathode bypass capacitors with Elna Silmics and the coupling capacitors with Musicaps. I also installed an earth lift system to stop the amplifier interacting with other equipment.
Overall the result was a very decent uplift in performance.
This preamp dates from the early 90s when it had a reputation for great sound quality. It stands the passage of time well and still sounds very decent. It had had various mods and servicing over the years, including main electrolytic capacitors, valve sockets etc.Someone had also replaced the ribbon connector with some Cat cabling.It is a hybrid valve /solid state design, with transistors used for the phono stage and valves for the line stage.
My work was to upgrade the coupling capacitors, and add a choke power supply by adding a choke and additional smoothing capacitor. Once this work was complete it transpired the original main smoothing capacitor was pretty spent, so that was replaced too.That took a while to find as it broke down after around 2 hours use, but was fine up until then.
The result was very worthwhile, performance has been lifted to a very pleasing level. The pre operates with a much quieter background, displays subtleties better and is more dynamic to boot.
This iconic little amp came in to the workshop for some TLC. Not much wrong really. A blown internal fuse but bias and every other parameter measured fine. So once checked and the fuse replaced the amp works fine and sounds good. There is a noticeable thump on switch on, which is typical for an amp of this age as capacitors and transistors age. A recap and change of transistor would cure this but for an amplifier of this age, I often simply install a slow start module as a cheaper fix for switch on thump. It really depends on how much the owner likes the amp and wants to invest in its future.