Sorry, but I don't know a great deal about Hofner guitar amplifiers. I am hoping that by adding this Fact File to the website, others who do know something about them or have pictures of them will make contact, allowing me to develop this page into a useful source of information. What I have learnt so far is:
The GV Series were manufactured between 1961-63 by a Munich based company called Eben, for Hofner. The Eben company produced units also for the German Hi-Fi brand Dual, and these days they manufacture circuit boards for other companies.
During the same period, 1961-63, Hofner appear to have also sourced a bass amp head and speaker cabinet from another company - Uniton AG in Switzerland. The amp head, designated the BV60 by Hofner, has a strong family resemblance to the famous Swissecho tape echo units made by the same company. The Swissecho units also appear in the Hofner catalogues of the period, but still retaining the "Swissecho" logo rather than "Hofner".
It has now been ascertained that the Schaller Company (who's factory is only about 30km from the old Hofner Bubenreuth factory) made the KV Series of amplifiers for Hofner from 1964 onwards. The evidence is that the Hofner KV-10 is virtually identical to the Schaller Piccolo guitar amp. Also, there was a Schaller KV-50 produced which was basically the same as the Hofner KV-50.
In 2017, Hofner brought out a new small boutique amplifier called the Hofner Little Fury. This is a combo amp rated at around 15w output, and fitted with a 10" Jensen speaker. It is fully valve (tube) driven and point-to-point wiring.
A very useful source of information on German manufactured guitar amplifiers, speakers, and effects units can be found at the superb website run by Hans Ohms in Germany. - THE ORCHESTER-ELECTRONIC WEBSITE
Hofner GV-6 Combo Amplifier
A 6watt amp with two inputs, simple volume, bass and treble controls. Size:17.25" x 11.5" x 8.5". In the Hofner 1963 catalogue.
Hofner GV-18 Combo Amplifier
An 18 watt combo with 5 inputs (2 microphone, 2 guitar, and 1 tape-phono-radio-echo !!) and Tremolo. Equipped with a single 12" loudspeaker. Size 23.5" x 15.75" x 8.75". In the Hofner 1963 catalogue.
A 36 watt combo fitted with a 12" and a 10" speaker. Otherwise similar specification to the GV-18. Size 29.5" x 19" x 9.5". In the Hofner 1963 catalogue.
Hofner KV-10 Combo Amplifier
A small solid state amplifier featuring tremolo and 10 watts output. Fitted with 10" speaker. Dimensions: 400mm x 500mm x 200mm.
Solid State 18w amplifier, fitted with a single 10" speaker. Dimensions: 610mm x 500mm x 220mm.
Hofner KV-25 Combo Amplifier
Solid state 25 watt amplifier, equipped with tremolo. Fitted with 12" loudspeaker. Dimensions: 610mm x 500mm x 220mm.
Hofner KV-40 Combo Amplifier
Solid State 40w amplifier. Fitted with single 12" speaker. Dimensions: 610 x 800 x 320mm.
A three channel amplifier, fitted with two 12" speakers. Tremolo, reverb, and analogue delay effects are built in. Dimensions: 705mm x 535mm x 270mm.
This model was an early hybrid design with a solid state preamp and a tube power amp ( 2x EL34 providing 50 watts). Two Goodman 12" speakers apparently were fitted. The power amp section was located at the bottom of the cabinet and connected with an octal plug to the preamp section in the upper cabinet. (Just like the old Selmer-Truvoice amps.) The delay unit contained a magnetic disc, similar to the old Baby Binson echo units, and three delay heads.
G30 Speaker Cabinet (Lautsprecherbox)
30 Watts output through three 8" x 7" loudspeakers.
G40 Speaker Cabninet (Lautsprecherbox)
40 Watts output through six 10" x 6" loudspeakers.
G60 Speaker Cabinet (Lautsprecherbox)
60 Watts output through six 11" x 7" loudspeakers.
Hofner G100 Speaker Cabinet Konzertbox)
100 watt cabinet loaded with a Goodman's Audiom 91 18" Speaker.
Speaker Cabinet (Baßox)
Bass Reflex design, fitted with two 12" Speakers.
Hofner K100 Speaker Cabinet (Kompaktbox)
100 watt cabinet fitted with four 12" Goodmans Speakers.
Hofner "Little Fury" Combo Amplifier
15 Watts Output through a single 10" Jensen speaker. Fully valve (tube) driven and point-to-point wiring.