mwg@mouton.UUCP (05/16/84)
I heard about Bob Carver's magnetic (?) amplifier a couple years ago. Is it good for a stereo system; what does it cost; and how do I get one? Thanx in advance for any advice. -Mark Garrett
mat@hou5d.UUCP (05/16/84)
Well, I've had one of his original model (201W/ch for *significant periods*)
boxes for two years now. I managed to drive it into safety shutoff ONCE
but it has been trouble-free otherwise. His newer units are better
at long-term reserve, although not as good as units like Haffler's or the
(sigh) Perreoux. (you know, a few thousand dollars, and you get an amp
whose power rating is simply ``adaquate for all musical needs'', with
4000 uf caps on the power supply and enough drive to put out over a hundred
amps for short periods.)
How did I drive the amp into safety? I had a TI thermal printer and a large
window fan running next to me and I was listening to Mahler's Ninth Symphony
(Bruno Walter on Columbia Oddessey) through my bedroom speakers (Boston A40's)
with the volume up quite a bit so I could hear it. The first movement uses
massed strings for minutes at a time. Strings have lots of power in the
high-frequency harmonics and the amp has a power-delivered integrator that is
supposed to protect against overheated voice coils. It's weighted to be much
more sensitive to the high frequencies, and it must have thought I was being
bad to my speakers. The sound cut out briefly without so much as a click,
and then came back on, and cut off again. I went into the living room where
the stereo is and the power-indicator lamps were flickering ``randomly'' at
half-brightness. I turned the volume on the preamp down just a little bit and
the amp came back on line as magically as it had shut down -- and stayed on.
This is the ONLY time is has done anything surprising. I can play back the
Omnidisk demo tracks at wall-shaking levels and I can play the heartbeats
on Dark Side of the Moon right up to about 1/4 inch cone excursion on my
A100's (acoustic suspension 8" woofer).
I don't know how the bigger Carver amps would have behaved.
By the way, the poweramps in Carver's *the Carver Receiver* are more
conservatively rated, and the unit has gotten at least two rave reviews.
--
from Mole End
Mark Terribile
(scrape..dig) hou5d!mat
,.. .,, ,,, ..,***_*.andrew@inmet.UUCP (05/19/84)
#R:mouton:-4000:inmet:2600080:000:1529 inmet!andrew May 17 18:09:00 1984 > I heard about Bob Carver's magnetic (?) amplifier a couple years ago. > Is it good for a stereo system; what does it cost; and how do I get one? > Thanx in advance for any advice. There are two Carver magnetic field amplifiers available. The one I'm more familiar with is the original, the M-400 (now M-400a); I own two of them. 1) Is it good for a stereo system? Well, yes... assuming a) that your speakers can handle the power, b) that you have a separate preamp or at least preamp outputs on your receiver ('tho Carver does sell an adaptor if you don't), and c) that your speakers don't require a common ground (e.g., no passive subwoofers or the new 'holographic' Polks). The reason for (c) is that one channel is positive ground and the other negative; any attempt at connecting a common ground will short one channel out. Sure makes it easy to bridge for mono, though! 2) What does it cost? $399 last I knew (mid-'81). I'm only using one of mine, though; contact me if you'd like to buy the other (needs minor work and is priced accordingly.) 3) How do I get one? Write to Carver (somewhere in WA; their address is in ads in the major audio publications) and ask for a list of dealers. Walk into one of these dealers with a fistful of cash... :-) Andrew W. Rogers, Intermetrics ...harpo!inmet!andrew 733 Concord Ave. ...hplabs!sri-unix!cca!ima!inmet!andrew Cambridge, MA 02138 ...ihnp4!inmet!andrew (617) 661-1840 ...uw-beav!cornell!esquire!inmet!andrew