Introduced in 1967, the E.R.40 was a solid-state
model with similar features to the E.R.30. It seems that the valve-driven E.R.15, E.R.30 and H.R.30
amplifier heads were immediate dropped in favour of the larger solid-state ER40
The E.R.40 had 2 channels each with 2 inputs, treble-boost slide switches, and bass, treble & volume controls. The rear panel included a socket for a slave amplifier. Recommended speaker cabinets were initially the WEM Dual Twelve and the WEM Super 40 Bass. After a year or so, the WEM Super Dual Twelve effectively took over from Dual Twelve.
Tim Remembers.......... "We had one of these in the late 60s : our the lead guitarist bought it along with a couple of 2 x 12" (I think) cabs to use as a guitar amp, but he didn't like it and it ended up as our PA. It actually made a very good PA (by schoolboy standards), I suspect because it's probably very similar to the PA40."
Bell Musical Instruments Advert - November 1967