… and there was sound!
Completed most of the remaining wiring and measured the HT and heater supply voltages before plugging in the valves:
HT = 197 V dc
Heater supply: 6.00 V dc
- switch off and wait a while for the HT caps to discharge – I’m rather allergic to high voltages ;-).
- Now plug in the two 6N3 valves and switch on
- Yes!!!! The valves are heating up
Before plugging in the SKRM-eTap2 module (which actually produces those luscious vintage echo sounds, courtesy of the FV-1 chip designed by the late Keith Barr (of Alesis fame) and carries the DSP program by my friend Piet Verbruggen) I did a loop through test of the audio path.
First, connect a jumper lead from the Left O/P of the SKRM (pin 13 ) to the left I/P (pin 2)
Now connect guitar to the front panel input jack and connect the rear output jack to a guitar amp. Switch on, wait for the valves to warm up, pluck those strings and – hey Presto – we got sound 😀
First impression – very little hum and hiss – and that’s without the case being screwed back together. The Arduino hardware is not powered up so I’m hoping that won’t generate much noise.