I first encountered Hound Dof in 1976 in a listening booth at a record shop Milsoms in Bath Somerset. They were connected to Duck Son and Pinker who sold instruments initially pianos but later guitars. They didn't do pop, rock, disco whatever. it was classical, jazz, folk, blues and later World. You could get blues albums there and listen to them before purchase. Very archaic by then but they used to get my money so it worked. They also sold sheet music, music books and tutorials like Country Blues Guitar or similar. Photo from this gallery of Milsoms pics.