HH was an old and very famous (in the UK)
Solid State Guitar amp maker.

Never ever touched a tube, unlike all others.
Originally (in late 60's, go figure) they made SS power amps so good, that they were chosen by the BBC for Studio Monitoring, which over there is the same as being Knighted by the Queen.
In fact, they also received Queen's awards !!!
And of course, most other Recording Studios chose them too.
Then they started making Guitar, Bass and PA amplification.
Top of the line, with luminous front panels, excellent hardware, etc.
And the first MosFet 500W and 800W power amps.
But then the tide turned to tubes, cheap oriental stuff undercut their prices, and sales fell.
They were absorbed by Laney, which continued making their more successful products for many years.

They also made very advanced PA systems, from mixer to cabinets, and they made their own speakers too , including drivers and bullet tweeters

Some guys were boasting about their:

and because they were *so* well made, most continue working perfectly, 20 or more years later. This is a picture taken at an open air concert, in 2011.
