Peavey EVH 5150
Now if I am honest, I am not a great lover of Peavey equipment. Thin PCBs, think copper tracks of PCBs and general lack of thought when it comes to servicing. Guitarists seem to like the amp’s sound, so I guess that’s the main thing.
I have seen quite a few of the amplifier pictured here. They have lots of multiway cable connectors linking different boards, all of which have a tendency to have intermittent connections. This particular model has a separate board with 5 x ECC83s side mounted. As I mentioned, it is a thin narrow board, secured only at the ends and at about 8” long, tends to flap about in the breeze. It flexes heavily when you remove and replace the valves. It is connected to the main board by several wire ribbons with IDC cable sockets. There is a plate that goes over the chassis with holes for the valves to stick their nipples through as a bit of support, but quite often this gets lost.
The common faults with this amplifier tend to be as a result of dry joints. Both on main board and the mentioned board with the ECC83s. Microphony is common, especially around the first ECC83 in the preamp stage. As a matter of good practice, I tend to fit silicone dampers. I have seen a few relays fail. These are in the channel switching and drive stages. They can become intermittent causing changes in volume etc. All these faults get exaggerated when the amplifier is placed on top of the loudspeaker and vibration get onto the chassis.
So there we have it. With a bit more thought in the physical design and layout and the use of slightly higher rate resistors all round, technicians would not look as grumpy as I do in the picture.
