John Bowers Active Speakers
Andrew Cecotti
opportunity of replacing them with some John Bowers (of B&W).
Does anybody know or have any experience with the JB active speakers?
Many thanks
Andrew
Malcolm
news:D2ji9.2282$bK2....@newsfep1-win.server.ntli.net...
> Hello all, I'm using Meridian M3 active speakers at the moment but I have an
> opportunity of replacing them with some John Bowers (of B&W).
>
> Does anybody know or have any experience with the JB active speakers?
I have a pair of JB Active Ones in perfect outward condition, working but
unused. I thought they were superb when I got them as did a wide variety of
reviewers. I have all the original brochures and instruction manuals if you
need to look up any details. They have 200watt LF and 100w HF amps on each
channel with discrete components throughout. I understand the transformers are
irreplaceable but otherwise they are very repairable.
Their weakness in my experience is that (with age) they tend to go into
standby mode if playing quietly. B&W tried twice to fix them for me but not
only failed, they made it worse. My guess is that the best way of fixing the
problem would be to bypass standby mode altogether. I took mine out of use
only three months ago replacing them with a pair of PMC active transmission
line speakers. The latter are less than half the size and to my mind were just
that little bit better.
My Active Ones are complete with original boxes and manuals and are
unblemished but require the services of someone confident in electronics to
fix or disable that auto-standby feature.
--
Malcolm
Norman Billingham
Andrew Cecotti wrote:
I had a pair for many years and found them superb, as did may reviewers
at the time.
They were only made for a brief time. John Bowers set up a separate
company to make and develop them. When he died Bowers and Wilkins
closed it down and stayed with passive speakers. However, B&W could
stil supply parts for them a few years ago and, more importantly, had
the service manuals.
The electronics can cause problems. The amplifiers work in class A up
to some power output, so there is a high standing current. This is set
by a variable resistor on the board. If it drifts high then the boards
get hot and the tracks can start to lift. This happened to mine but B&W
simply hard wired some of the circuit board and it was fixed - they also
set the currents lower.
The plug/socket connectors between the boards and the speakers could
also go intermittent - I replaced mine.
If you're considering buying a second hand pair, whip the amplifiers out
of one (just undo the heap of long threaded bolts and let it tilt back
into your hands). Have a look at the circuit boards - a bit of brown
staining is OK but if they are showing signs of charring and lifting of
tracks be a bit careful.
Andrew Cecotti
"Norman Billingham" <n.bill...@sussex.ac.uk> wrote in message
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