This review details the "Boomster 933 Mark II," a clone of the original Breeze Audio amplifier, highlighting its impressive performance, build quality, and sound characteristics for its affordable price point.
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hi guys in this episode of the Clone
Wars we'll talk about bommaster 933 Mark
I clone amplifier produced by Breeze
audio called also Breeze high-fi uh yes
the original amplifier was produced
between 1996 and 2004 and it was pure
power amplifier with balanced XLR inputs
only uh this clone is based on the
internal structure and on the principles
and diagrams of original amplifier
however it has additional volume control
here and it's using single-ended inputs
uh it doesn't have any balanced inputs
whatsoever um yes um the
specifications uh this is uh basing on X
amp Build architecture it's using this
coupling so we'll see some operational
amplifiers inside uh the power to
specification uh on paper is 70 wats
into 8 ohms and 120 wats into 4 Ohms uh
but the U the shop U the store also um
provides additional information that the
actual measured uh Power output was uh
almost 150 watts uh for for ohms so
that's quite nice uh uh I got this clone
uh because of uh the numbers uh and
branding uh but the numbers that uh made
me uh think about it uh were uh three
things the first one dumping Factor it
has a huge dumping faor Factor because
according to the data it's 3,000 so The
Dumping factor for this amplifi is 3000s
that means that the terrorist says that
it should be able to stop the membranes
of your speakers in place uh another uh
interesting number is total Harmony
Distortion uh according to the
manufacturer data THD for this
amplifier uh is between
0.002% at 10 wats so 10 watts would be
your regular listening level probably uh
and uh it goes up to up to
0.011 at 70 Watts 70 Watts uh for the
most for would be uh I don't know uh
defining level uh so that's still very
very clean in both cases these are very
very low harmonic Distortion numbers and
the third number that made me uh pick
this amplifier is signal to noise ratio
uh it reaches 107 DB which means that
the distance between the noise flow and
the signal uh level uh is uh way above
100 DB so so pretty pretty good numbers on
on
paper uh what I've measured here when I
was uh doing the tests uh is the fusing
keys that the noise floor is uh actually
very very low uh you can you can't hear
any kind of hising even with uh very
sensitive uh motion Transformer speakers
uh when you'll get your ear to the
speaker and you'll Max the volume it's
still that silence
also no hum from the Transformer
whatsoever but we'll get to that uh I've
measured the power usage the power
consumption at uh 36 Watts when idle and
40 Watts uh when playing music the
temperature the temperatures you might
say were very very healthy because uh
they were between 36 and
37° centigrade yes uh this amplifier
comes into uh two flavors you can choose
between two external chassis uh this one
is actually the cheaper version uh I got
it uh for
$250 shipping excluded and shipping was
about uhu $50 I think uh shipping to
Europe so all in all
$300 uh for this version uh the more
expensive version uses CNC machined uh
chassi also made from aluminium but uh
the other version uh looks almost
exactly like the musical uh Fidelity A1
clone that I reviewed uh so I like the
look of this particular chassi better
and I didn't want to have two amplifiers
looking almost exactly the same so the
fact that this actually is cheaper was
additional bonus for me uh uh yeah
threat from verat speaker verstat German
YouTuber uh threat from speaker
verat uh has a short review of this more
expensive version so you can take a look
at the more expensive chassis and you
also will be able to uh take a peek
inside of the
amplifier uh there is one difference
between this unit and the one that he
got uh the capacitors power bank
capacitors are different branded uh but
more on that later
yes so what do you get for your $250
$250
uh the front power switch power LED
which looks very nice because of this
small place uh hidden here uh when it's
uh lighting up uh this whole area is wed
so it looks very nice uh volume pot here
and a very funny thing uh in front of it
uh very lucky typo uh so you don't have
boom here but you have boomster here boomster
boomster
933 high-fi
amplifier yes On The
Backs we have solid aluminum fins very
good and in the back we have speaker
tabs quite good looking and solid
speaker tabs that will accept uh B wire
spade and banana
connectors uh they are looking quite
nice we have RCA connectors for left and
right channels uh we have input voltage
selector because this can operate on
110 uh volts power grids uh we have uh
power cord connector and integrated fuse
compartment here uh the specification
says that the actual model number is PA
933 uh the model with the more expensive
chass has Dash and uh two number two at
the end and it also says that it's
specified for 120 watts per
channel uh the whole amplifier weighs
around 10 kilos it's very small it's
very compact but it's quite
heavy yes the build quality the build
quality the build quality is excellent
It's solid aluminum and that kind of
build quality is actually spoiling me
because I came to expect that kind of
build quality on the amplifiers that I'm
reviewing so unfortunately all our local
Brands will have a hard time now because
I'll be expecting at at least 3 to 4 mm
thickness on the
chassis yes what's
inside uh inside of this amplifier uh we
have toal Transformer with uh thick
shielding uh which is actually actually
very good and it's not quite common on
the power amplifiers that I reviewed
some of them uh had just bar
Transformers uh in the open uh The
Shield is nice uh because it provides
additional shielding from Emi uh for the
uh left and right channel boards uh we
have some nice ceramic resistors here uh
all of the red capacitors are German
VMAs uh which is very nice uh the
transistors are sunkens let's take a
look at them
y uh we also have uh Ron transparent
relays uh what we don't see here is that
we do not have any kind of internal
fuses on the boards inside of the
amplifier the only uh fuse is in the
back in this compartment I'm mentioning
because I'm mentioning this because some
of the other amplifiers that I reviewed
uh had also additional fuses inside uh
but that's that's that's perfectly fine
this one should be uh good enough
uh yes uh the main capacitor Banks uh
each one of these capacitors is uh
10,000 microfarads rated for 63 volts
and they are they are produced by a
light I don't know the brand if you
happen to see that b earlier you may
give me a shout in the comments so that
would be one of the things to upgrade in
the future uh the other interesting
thing is
that the rectifiers here are using head
SNS uh which is also not very common and
actually I'd say that may be very rare
uh in other equipment that I reviewed
you can see that the boards are marked
with uh bumas 933 Mark I version three I
suppose that's the version of the PCB
board uh yes we have blue Alps for
volume control and we have one thing
that I don't really like uh here and
I've already mentioned mentioned that in
my first look video uh the LCA inputs
are going from the back of the amplifier
to this symmetrical
connectors uh on the PCB symmetrical
because the other PCB looks exactly the
same but it's just mirror design so your
input signal travels then along the PCB
board Edge right up to this point and
then it goes to the connector that moves
that yes so uh the track is too long I
don't like that idea idea and uh since
uh I'm planning to bypass the volum pots
uh volum pot anyway uh I will
be making uh cable that will be running
straight from RCA input some kind of
good quality to shielded cable I don't
know from Mami uh maybe some kind of
microphone cable from canar or Sumer uh
and the cable will be running from the
RCA straight the board you have marked
uh right input and ground uh points here
and left input and and ground points
here uh so I'll probably uh use uh
separate C for that in order to be able
to uh get back to the stock connection
Set uh the other thing worth mentioning
is that uh these the cables that are
connecting the speaker output from the
board to the actual speaker tabs uh are
also candidates uh for maybe replacing
with something ther and better quality
and uh at the same time uh I would just
order anything straight to the tabs and
and the board um but uh the connectors
used here are not exactly a bad solution
uh the idea uh for using them is very
simple uh This is highly modular build
and it's very easy to uh remove
everything to disconnect all of the
cables and to get access to the boards
uh which is a very good thing if you're
going to be servicing this unit or if
you will be uh doing some uh molds like
for example replacing capacitors uh it's
a very good thing because in order to
get to the bottom of the PCB you don't
have to theholder any kind of theholder
any kind of cable you just need to
unplug everything so that's it uh yes uh
we have some transparent on on relays
here uh we have head SNS on
the rectifiers which is a very nice
thing because it's one of the the few
that has them uh and I think that's it
about the internal build uh another look
on the sun
transistors and that's
it uh
yes so all in all I like the build build
inside I like the quality of the
components used here it does leave some
room for improvement if you're into little
little
it yourself uh you can you can replace
some things uh yes
now we've covered the build the
specification the internals let's talk
about the most important thing of the
review let's talk about the sound
quality of this
amplifier uh well I've divided this
section into the usual Parts uh so let's
start with the base uh the base of this
on this amplifier is very strong and it
gives very solid uh foundation for all
of your music and it has absolutely
great texture uh the one of the um
positives of having such a high dumping
factor is that uh you're controlling the
membranes of the speakers very precisely
uh so this translates into very
involving uh sound into very involving
base uh that makes you track everything
that's happening down below uh all of
the BS guitar lines uh all of the BS
textures present there are absolutely
Splendid uh the base doesn't hold back
uh it's very strong it fills the whole
room uh with the base uh but it's not
the thick muddy type of Base it gives
the solid foundation and it's just
everywhere so yeah I absolutely love uh
the base on this
amplifier um
the important thing to note here I think
this is the first time that I'm noting
this uh in um review uh of any of power
amplifiers that I got so far uh is that
the this base is a very uh rhythmic one
it makes you tap your foot it kind of
reminds me uh in this regard uh nine uh
units that I had in my time uh I had
nine Unity cutes two versions of unity
cute and I had uh one of smaller NN uh
Power amplifiers um and this amplifier
also has this uh quality uh I'm not
saying that the other ones were not
rythmic but this one will make you tap
your food to almost
everything uh including uh some
classical music uh the great example for
that would be Topsy uh Topsy uh is so WR
here that you in voluntar uh will use
your hands or your feet to tap to the
written um yes going to the MS uh the MS
are full bodied uh and uh we have very
natural sized
voices uh the piano the piano here uh
was very detailed uh very uh melodical
but also full-sized uh you didn't have
that uh idea that the sound of the piano
comes from some point in space but you
actually listening to the amplifier you
actually feel like the piano is a big
instrument and you can actually hear the
size of this instrument I know this sign
sounds weird especially for someone who
never heard uh or is about to hear for
the first time uh good quality amplifier
but uh for those of you that have some
um possibility to hear a good quality
audio stuff you'll know what I'm talking
about uh you can actually hear the size
of the instruments and with this
amplifier the same goes for brass
instruments uh they are very detailed
they have very nice textures but also at
the same time you almost able to hear
the size and the weight and the
solidness the the of the instrument the
fact that it's made uh from metal and
that it has some uh weight behind the
sound so that's also very surprising
especially given the price that was only
$250 that's wow uh okay another thing
that I've noted here uh it's
detailed uh and the coral songs uh these
convey a lot of emotion um and what's
important uh they are detailed so you
are able toar the distinct voices uh
within the cor uh it's not like one
sound of the group of people singing
together but you can actually hear the
members of the car singing together
that's very important and it's that
that's very uh good thing in my book uh
but at the same time uh there is no
listening faure and no uh calance
whatsoever here and the Seance gets us
to tble
uh no the t is not cilant the t is very well
well
extended uh it's uh it
um at the beginning when I started my
session I thought that rebble is a
little bit dry but then I
realized that uh I didn't let the
amplifier uh to get warm and I've waited
for like 10 and 15 minutes and the tble
was perfectly fine so the thing to note
here and I repeat that at the end of the
review is that this amplifier sounds
best after something like 15 minutes of
warm up uh it reaches this 36 57°
centigrade and it sounds best then uh so
very extended very transparent uh treble
maybe maybe they could use a little bit
more of the top uh and air but that's
just a small amount and this may come
from the two things the first one is
that uh I'm electrostat guy so I love
plenty of air at the top end and the
second thing is that U since uh you're
hearing the instruments with the full
size sizes uh this means that maybe I'm
perceiving the sound uh
uh how to say that uh how should I word
that uh if the size s of the instruments
are bigger then the spaces between them
will be a little smaller so maybe that's
something that I'm perceiving uh and
that would actually translate into a
very good trait of this amplifier so
anyway the treble
extended good precise detailed no
listening F uh fatigu uh no Cilan
whatsoever uh and one thing to note here
it's very delicate and musical uh the
symbols on Dance of the witches by John
Williams were absolutely stunning um
yeah I think I make a video on the TX
that I'm using uh for test purposes so
anyway Dance of the witches is one of
them and the symbols in that songs in
that song we're absolutely great with that
that
amplifier moving on to the detail uh
closing the Travel section and moving to the
the
detail the tble is very good and very
precise but this is the type of the uh
detail that's not in your face uh the
amplifier doesn't push uh detailed
information in your face and it's not
forcing you to focus on the details uh
but at the same time everything is still there
there
you can uh focus on single instrument
you can focus on single voice and get
all of the detailed information that's
hidden in the track so that's very very
very good in my opinion uh because it's
musical it's not analytical but at the
same time all of the detail information
all of the analytical side of the music
is still present there so that's a very
good point here
uh I love the details on that one uh and
the detail detail sorry my problems uh
the detail um moves us towards uh scene
and imaging uh this amplifier has a very
good Center image uh the instruments as
I said are full-sized the stereo Imaging
is also very
precise uh it's able to easily get the
sound away from the speakers uh when you
close your eyes listening to the music
uh you have no uh feeling whatsoever
that you're listening to two
speakers uh once you close your eyes the
sound gets away from the speakers uh
it's in the front of them and it's gets
and it gets very wide so that's that's
uh also another very good
trade uh the it's not the 3D imaging
King uh because uh the depth information
and height information were there uh
they were not as uh on the same level as
in best amplifiers that I've tested so
far uh but they were nevertheless very
very good the best was left and right IM
much there was death information there
was some he
information uh it was not the best in
theout but it was uh very very good
nevertheless uh I will have to as I
wrote a couple of times already I'll
have to do detailed comparations uh
between different amplifiers uh
different listening sessions and then
I'll be able to uh determine the exact
uh quality of the scene here but it's
very good it is very
good uh yes
um when I finished my in sessions with
my Dynamic speakers and by the way the
equipment uh used for the testing
sessions uh will be described in the uh
video description uh the the detailed
information uh will be uh provided there
uh when I finished my regular listening
sessions as you probably know uh at the
end I'm switching the speakers to my
electrostat speakers because these are
like uh x-rays x-rays for audio equipment
equipment
uh and I'm uh doing the listening
session again I'm checking uh what's
changed uh with my uh Martin Logans
because they reveal everything and uh in
this case I have just uh a few notes uh
the first one about Imaging yes Imaging
uh for the death and height could be a
little better better but uh what's
interesting uh is the fact that the
separation between instruments was
excellent so very good stereo
information uh a little less information
on the depth and on the head but at the
same time the um very precise
information uh on the
separation so the instruments and the
sounds were not blending together but
they are very clearly separated and that
was very nice
thing uh uh yes uh one more thing uh
that maybe uh should be obvious by now
this amplifier was able to properly
drive my
electrostats and that's not something
very common uh these are a very
difficult load because uh they don't
have a very high sensitivity uh they
have 90 DBS and the piggest problem is
that they present a difficult load
because the tble the top end in region
of 20 kils uh makes them go to as low as
1.5 ohms uh 1.2 ohms uh which means that
uh it's very hard uh for most of the
amplifier to give proper proper able
extension with electrostats and this
little Powerful Beast could do that the
Reel was absolutely very very good uh
the extension was proper the detail was
there the airiness was there so yeah
small but
powerful uh yes and
uh this uh arrives us to uh the last
part of the review uh my loose thoughts
and the summary uh loose thoughts as
usually I have different things that
I've noted during listening sessions
that do not exactly fall into uh
previously uh this categories so the
first thing uh this amplifier I think
may be a bit of the on the darker side
because uh of the base I said the base
is everywhere uh so it's not light and
air there's no fair is flying around
it's a little bit on a darker side but
not exactly warmer side uh and I like
that I really like that it was a very
nice pairing with my
electrostats uh yes another thing that
I've noted uh is uh that the base was
absolutely stunning yes the dynamic
swings were also absolutely stunning it
can go from very quiet to very loud in a
second and it can go from very loud to
very quiet in another second stopping
your speakers in place uh once again
High dumping Factor uh yes the good
sense of Rhythm and feeling of power
that's something something that uh
you'll get when you're listening to this
particular device for
example uh for the for being powerful
and the written uh London F harmonic
Orchestra uh made a uh set of recordings
uh with uh computer games music and uh
Listen to Call of Duty Modern Warfare uh
main uh Team uh from that set of
recordings by the way I highly recommend
the whole
um the whole CD um yeah uh this mic uh
qualities as I said are reminding me of
uh names uh it's a fun um that makes you
want to go louder and louder and uh
that's actually true I during my Lessing
sessions uh my wife shouted to me that
the other people living in other part so
maybe I should tune the room down
because it makes you want to go louder
you want to feel the Earth tremble the
base is so good here and it was fun
until I had to lower the volume
but once in a while yeah uh okay as I
said it needs about 15 to 20 minutes to
sound best so that's a interesting thing
most of the solid state amplifiers uh do
improve their sound after a while uh but
it's quite short uh this one yeah 15 to 20
20 minutes
minutes
uh one thing worth noting here is that
if you're following my channel I've
already reviewed a couple of power
amplifiers this one is different this
one is really really different it has a
very interesting signature a signature
that I loved it's very fun it's very
powerful uh but it is
different uh you always ask me which one
is better
and I always say at this level the
competition is so close that it's not
about who is better because there is no
one single amplifier that is worse they
are different flavors they differ in the
way they present the sound so you should
get one that will be uh maybe not not up
to your standards but uh that will fit
your partic particular uh listening
habits the best so anyway
this one is so good and it's so fun and
it's so different uh that regardless of
the outcome of my quest to get the best
amplifier for my electrostats this one
stays in my collection it's so good it's
so small and it's so powerful that I
want to have it it needs to stay with
me uh if I would have to coin the slogan
to Market this thing I would say that
this is a small box of condensed power
and fun
uh that's also something that I noted here
here
um uh for for those of you that would
like to mod this amplifier maybe a
little like me uh one parting thought on
moding is uh that there is a moding
potential here the wires uh maybe the
capacitors Etc uh but yes I will change
the wires yes I will bypass the pots but
I'm a really afraid to touch anything
else including cups not because I break
something but because I really really do
like the sound quality and I am afraid
that if I use some better Parts I will
destroy this uh delicate State uh this
uh delicate Harmony between base and
Trel here um I've also noted that some
of the capacitors on the
board like these ones have uh higher
values than the descriptions on the
boards I've asked about that b I
contacted the manufacturer about that
and once I have the explanation for that
I let you know I'm mentioning this now
because uh there are usually two cases
uh for such situation the first one is
uh when you're changing the the values
of uh elements uh on the board because
your listening sessions say that you
should slightly change them the second
one is uh when you're having the
available stock of components and you
replacing capacitors with the next
closest Value because you don't have the
particular value uh in your stock and it
doesn't change the change the sound
signature uh nevertheless uh I've asked
Bree about that and I'll post uh answer
in the descript description of the video
but for
now seriously guys I'm quite terrified
to change anything here except the wires
here yeah because the wires will not
affect the sound that much and the
changing wires here will not affect the
sound in any kind of negative way this
input signals bypassing the volume pot
that's that's not that's nothing it will
improve the sound but everything else
I am afraid to touch
it uh okay
one Lal One summary for the end of the
uh sound quality part for the money it's
absolutely Nob brainer don't think about
that don't wonder if you should get one
or not if your bus l or not just buy one for
for
$250 and compare it to your other amplifier
amplifier
it's so different and so fun and so
powerful and precise at the same time
that it should be a part of everyone's
collection and one more thing this was
my first contact with bras CL uh you'll
probably aware that there are two um
available two others available on the
AliExpress the first one is B Master uh
99 and the second one is B 956
and this little guy made me very
seriously wonder about getting the other
two it is so good that I really want to
hear the bigger and more expensive
Brothers of this
amplifier so I hope you enjoy this video
stay tuned for other videos I have a
quite large collection of the stuff that
I wanted to show you here we have
another set of uh preamps and Hood
amplifier that are burning in right now
I'll be getting back to my cable reviews
yes you see fake noost Valhalla too
getting burned in there if you have uh
any questions feel free to ask them in
the comments I am trying to answer all
of the questions and all of the comments
usually uh once or twice per day uh so
you shouldn't wait uh very long uh if
you like that video and you if you feel
like you'd like to buy me a beer I'm a
beer guy and you can do that using
supers or donations or whatsoever I
drink to your health uh yeah stay tuned
for other videos that will be coming
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