One of the wood finish variants eventually addressed the problem of controlling the volume from the speaker.
Up until now, the only way to suppress the noise was by placing a hand over the speaker grill. While this method; though pretty basic; could according to the manual 'be used to obtain tonal variations', some better way was needed if the Stylophone was to be used in the presence of less enthusiastic folk!.
A volume control in the form of a rotating knob was added to the bottom left hand corner of the speaker grill, just above the two slide switches.

This model was marketed as the NEW SOUND Stylophone, and contained the '555' chip. This cut down considerably the actual amount of electronic circuit board components need to operate the unit satisfactorily. Apart from the addition of a volume control, when the back is opened on one of these, there is not a lot to see inside.
(In fact, 50% less compared to an earlier model).

NEW SOUND component layout

The New Sound model, with its' wood effect finish, was quite different in appearance to that of it's earlier counterparts, together with the newly added volume control. There was only so much that could be done with these little boxes without losing its' unique size, design and appeal. Cosmetically, it is just the grill that has changed; the keyboard and stylus remain the same, and this example carries the numbered keyboard overlay as opposed to the musical notation type featured on the other wood effect Stylophones shown earlier.
The keyboard has also lost the dark upper spacers between the keys.

The wood effect of the NEW SOUND Stylophone would mirror the appearance of the much larger and more versatile model 350S.
(This model from 1975).

The bright yellow box packaging, with the familiar see through cellophane window still featured Rolf Harris on the front, but the free record was no longer included.

The tunes featured in the booklet that came with the New Sound model were:
Helston Floral Dance, When The Boat Comes In, The Big Ship Sails On The Alley-O, The Yellow Rose Of Texas, The Entertainer, and Michael Row The Boat.
Not exactly the cutting edge of popular music, but that probably wasn't the point.
Even though pretty bland, most people would know at least a couple of the songs, making the learning process a little easier.

Volume

Why fit a volume control when you have a spare hand!.
Although a pretty basic addition to any sound device, this came much later...