AKAI normal EWV 2000 and remodeled EWV 2000 are simultaneously played and tested 

For both stations, INST IN / OUT dual-purpose connectors are added to EWV 2000 so that it can be played simultaneously with one stick.
The sound source above is a normal transformer, the sound source below is equipped with a switching power supply (85 V to 265 V) that fits inside, and checked with an oscilloscope whether there is change or noise in the output waveform.
Although the sound is coming out, it is the sound of the modified EWV 2000 below (the top is not ringing)
Waveforms are also upper (yellow) transformer type, lower (blue) switching type.
Well I think that there is little difference.
Here is the remodel of EWV 2000
wp.me/p7AhKJ-ad