thebrunx

Ok, Waiting.

Post the equivalent measurements of the Carbon for comparison please.

Topping wants to take over hifi audio, monopoly style.

Seems like everyone is still placing an order.

aren't Topping known for being giant killers?

New King?

my tube filament 6.3VAC supply was grounded with two resistors, (but too low of a resistance, only about 150ohms each) I did this to create a virtual center tap to avoid some annoying tube buzz I was getting from the beginning, it solved the buzz but I guess this added circuit also created a voltage potential that exceeded the el34 cathode to filament maximum voltage ratings and would time to time short circuit v- to gnd (arc in the tube) and pulled too much current in those moments that fried one of the KSA1220A transistors randomly. thank God I had fuses between my amp and DC power supply which probably saved my power supply every time. so with all this in mind, you got to wire the Filament correctly as Kevin has pointed out to avoid creating such a potential in the tubes.

Solved.

Hello, I build the DIY Blue hawaii some months ago, and everything seems done according to the "book". but I have got a big problem. every now and then a KSA1220a Transistor goes bad randomly mostly at start ups but sometimes even in the middle of listening sessions. The KSA1220a transistor replaced the 2SJ79 from the older schematic (under the tube). I have tried different tubes, also transistors from different sellers. the problem remains! it works a few weeks than one transistor dies randomly. Has anyone experienced such a problem and know what the problem could be and how to solve it? its so annoying.

Why these mods?... IMO. If better sound performance is what you are after, I doubt any of the above mods will make any worthwhile audible difference, If any.

Four big snap-in caps.

when I changed the caps on my T1 (not T1S), I remember the original caps did not have the leads symmetrically center oriented like the caps they make nowadays (Weird). Because of this, I needed caps with a smaller diameter than the original for them to all fit in together.

it has a small arrow indicating the selected voltage, you can pull the jumper out and flip it around to select the right voltage for your country.

is there no voltage changer jumper build in your amp? normally at the back panel, or on the bottom from inside.

Has anyone ever tried to measure whether tube-rolling the blue-hawaii or GG for that matter, actually makes an objective difference?.