wjm@lcuxc.UUCP (B. Mitchell) (03/18/85)
I've been quite pleased with my Hafler 110 preamp (and 220 power amp) which
I've had for 2 1/4 years now. The only problem I had with the assembly of
the 110 was that the secondary leads on the power transformer were not
color-coded the same way as listed in the instructions. (At that time, Hafler
provided all 110's with multi-voltage transformers - they may still do so)
A quick DC resistance check with a VOM told me which leads were which, and
the rest of the kit went together very smoothly.
I've never had any problems with the 110 - The 220 went together even quicker -
The only thing you assemble on a DH-220 is the power supply and the chassis,
everything else is on two pre-wired PC boards. Unfortunately, Hafler supplied
a bad transistor or bias resistor on one of the boards in my unit, and the
resistor went up in smoke 2 hours into the initial burn-in period. I sent
the unit back to Hafler, who fixed it without charge (since it was their error
and the kit was correctly assembled). The amp has worked perfectly since then.
You should have some experience building electronic kits before tackling the
Hafler kits (a Heathkit or two will do nicely) but the instructions are
fairly good (not up to Heath's traditional standards, though - I haven't
built a Heathkit lately so I don't know if the new ones are in the same league)
and you don't need an EE degree to follow them (admittedly, my 3 degrees in
EE came in handy in tracking down the mis-coded transformer leads though :-))
Regards,
Bill Mitchell ({ihnp4!}lcuxc!wjm)
186,000 miles/sec - its not just a good idea, its the LAW