Big in the USA and virtually unknown in Europe, Ultrasound (by Dean Markley) has a large range of acoustic amplification. The AG50 DS4 is certainly a popular amp Stateside and has a homely, rather seventies look to it. The slightly sloping fronted cabinet is covered with a light tan leatherette, which could be a little tidier in places, with chromed metal protectors on each corner and an old-style hi-fi speaker-type grille cloth that hides the two eight-inch coaxial speakers. It’s actually a stereo 25W-per-side unit. It’s not overly weighty at 10.9kg (24lb), so it’s easy to carry with the top-mounted handle.