A push-pull amp from China based on super tubes 6550C from Russia.
Phone rings .... "should I buy the music Angel so you could tweak it
for me please ?!?!?! "
Oh no, not another angel PLEASE !!!
I was sick and tired of the angel-mania when my buddy called. So I used
him as a guinnea pig - asking to find an angel-alternative. He
presented me a couple of candidates, and I picked the BEWITCH.
2 weeks later the amp was in my (what was once) living room. It
is still a room, but I dunno about the "living" part.
Anyway, why do I think that BEWITCH is FANTASTIC and it kicks the
Music Angel's ass (at least the KT88 Angel, not yet the 845 Angel.)
Well, for a number of reasons.
Comparison is not fair perhaps, but anyway - the Angel looks a little
bit on the "made in labour camp" side of things. The Bewitch looks like
made in Europe.
Aesthetically, the Angel is on the slightly vulgar side of things, like
it is made to impress other fellow Chinese.
The Bewitch is a cool, simple design, not flashy or vulgar at all.
The feel is very positive and solid. It is a heavy furniture, very very
nice. Bigger and more substantial than the Angel.
Most importantly - WHAT IS INSIDE the BEWITCH ?
The mounting is on one big PCB - not good for tuning, but guess what -
It needs very minimal works, it is good as it is.
It is MUCH BETTER than stock Angel, but a little bit worse than tweaked
Angel KT88.
The tube choice is first class - best Russian 6550C's in power section,
just like in Manley and VTL amps. Very good octal tubes in the front,
good parts, good layout, some silkscreen descriptions, etc.
Generally - it gets my seal of approval in the mid price cathegory (my
sample costed 600 bucks shipping included).
A very safe buy, a good entry into tube world.
And it is very powerful too.
For all perfectionists out there, in my sample nothing rattled, buzzed,
or hissed whatsoever. The amp is stable, runs cool, and plays well.
I even liked it in tetrode mode not only triode (strange, I usually
hate tetrode)
Good transformer and a choke near it.
Above: oryginal schematics Bewitch 6550 amplifier from China
Some of my modifications ideas:
1. Replace the input tubes - 6N9's with russian 6N8's or USA
6SN7GT or similar (all four octal tubes can be the same). At the
cost of some amplification ratio (overall volume) we get much cleaner
sound. The currents is adjusted by the resistor change in first tubes.
as on the picture below.
2. Remove global feedback loop. If you find a problem - use 200K
instead of 100K in the loop.
3. remove R22 and replace it with a MKP cap.
The amp has big power supply tube diodes which I havent touched. They
do affect the sound I heard.
I guess we can try to replace them with two simple diodes N4004
per each tube. But the tubes lkook good and they can of course work.
These will be the first tubes to die - rectifier diodes are short
living tubes.
There we go - we have found a great amp that can suit everybody. The
more ambitious audiophiles can use it for the bedroom system, but it
will not be out of place in serious highend system context.
In my case it ended up with lampized Nakamichi player (TDA1541A) and
P17 speakers based on Saba and Lansing drivers.
This system has serious pretensions to be high end and even top league.
