12 Technology Drive, Ste.13   East Setauket, NY 11733

 HIWATT AMP REPAIR

These are just about my favorite amps of all time. There are really two kinds of Hiwatt amps, those made before 1981 and  later production.

"Dale R" amps 1965-1981:

If there was a award for beautiful wiring and construction, these would take first prize. The layout on these amps is excellent. The actual construction was done to British Mil-Spec standards by a shop that built electronic equipment for the Royal Navy. Tight wiring, perfect right angle lead dress, hand laced wiring harnesses and top level components. These amps have HUGE transformers and insanely overspec power supplies. In addition, most of these use a  modified Mullard driver circuit with a set bias point that gives a very clean, distortion free signal to the output tubes.

When we have one of these in the shop I really like to treat them as restoration/conservation items and just try to replaced any dried out filter caps and overheated resistors, clean the controls and rebias the amp. These amps drove the output tubes really hard, and most modern tubes cannot take the current. I usually set them a bit cooler but not enough to affect the tone. If parts have been changed over the years I try to restore the amp as close to original as possible, using resistors and caps that are as close as possible to the originals. These are amps I will not alter or screw around with, only get them back to as close to original as possible. These amps are the British version of "Loud and Clean". Perhaps a good indication of their quality it that David Gilmour of Pink Floyd still uses the same four Hiwatt lead amps for over forty years.

"Transistion" amps:

These are really not all that bad and would be considered decent amps if not compared to the classic Hiwatt amps. These amps use circuit boards that are pretty poor and develop bad solder connections. In addition they used total crap tube sockets. If gone over carefully the can be good sounding amps. I have done a few "retro: conversions of the amps to turret board construction and the results have been very good.

Modern Hiwatts:

For a while now there have been new Hiwatt amps made with build quality  a bit similar to the original Dale Reeves models. Have had few of these in for repair of minor issues and they are well made and good sounding amps. Not up to the level of the old beauties, but rather nice amps.

 These pages last modified 02/23/2011