MSB Technology M203 User Manual

M-203 AM p l i f i e r
(p e r Mo n o AMp)

Sp e c i f i c A t i o n S

In p u t s :
tr u e Ba l a n c e d (Xlr)
In p u t Im p e d a n c e 36kOh m

sI n g l e -en d e d (rca)
In p u t Im p e d a n c e 18kOh m

In p u t se n s I t I v I t y :

4.34 vp p @ 200W
(hI g h ga I n +28d B )

8.68 vp p @ 200W
(lO W ga I n +22d B )

cO m m O n mO d e ra n g e :
+/- 20 v

ma X . lI n e a r In p u t ra n g e :
10 vp p

ma X . In p u t vO l t a g e :
20 vp p

tr a n s I s t O r s :
al l BI-pO l a r

M203

Users

Fe e d B a c k :
0 ne g a t I v e lO c a l Fe e d B a c k
0 ne g a t I v e gl O B a l Fe e d B a c k

da m p I n g Fa c t O r :
80

sI g n a l t O nO I s e ra t I O :
>120 dB

pO W e r ra t I n g :
>200 Wa t t s a t 8 Oh m s
ca p a B l e O F d r I v I n g

a 1 Oh m l O a d

st a t I c pO W e r cO n s u m p t I O n :
250 Wa t t s

FI l t e r ca p a c I t a n c e :

220,000 µ f

tr a n s F O r m e r s :
du a l 600W tO r O I d a l
tr a n s F O r m e r s .

dI m e n s I O n s :
13” d I a m e t e r X 18” t a l l
100 lBs
sh I p We I g h t 120 l B s , 24 X 20 X 20

Manual

Rev 1 (7/12)

cO n t r O l Fe a t u r e s :

- sW I t c h F O r Ba l a n c e d

O r sI n g l e -e n d e d O p e r a t I O n .

- pO W e r On /st a n d B y /OF F

- re m O t e pO W e r cO n t r O l

- hI g h a n d lO W BI a s mO d e

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M203 Amplifier Users Manual

A Simple Approach

The M203 monoblocks provide a simple but effective approach to good sound. An amplier does two things, it increases the voltage
of an audio signal and it increases the current. Class A ampliers completely overlap the positive and negative signals providing great
performance but with huge power losses. Class A-B overlap only a little with much lower power use but compromised performance.
The MSB amplier uses a fully CLASS A stage to increase the voltage signal, and a CLASS A-B stage with no voltage gain to increase
the current supplied. This unique hybrid gives the best of both - a great performance with reduced power requirements.

Setup and Quick Start

This is easy. Plug it in and go. The power switch has three
positions:

ON =Green, Standby = Amber, and OFF = Red.

Power - The power requirement depends on the speakers

being driven. The ampliers will both run off a single 120V,
20A circuit easily with a standard 8 ohm speaker load.
With a 4 ohm load, they will still run off a 20A circuit, but
with a 2 ohm load, each amp must be on a separate 120V,
20A circuit.

Inputs - The amplier will accept a single-ended or balanced
input.

Outputs - Connect to your speakers.

Burn-In

The concept of burn-in is little understood. Does it take your ears
some time to get used to the incredibly detailed and life like sound
of an MSB product or is something actually changing. The feedback

we receive leads us to recommend at least 100 hours of burn-in on
this amplier. Customers generally recommend one month.

Heat and Bias Setting

These ampliers will get quite warm. They should be used in an open air-conditioned
room with nothing covering them. Operation in extreme conditions will cause failure.
Heat is not reduced in stand-by mode. If your listening room is subject to high
temperature when you are not using these ampliers, please turn them off when not

in use.

The Bias switch on the cover allows you to use the amps in two modes. In high bias
you get the best performance but the M202 will be warmer to the touch. Normal bias

sounds almost as good and runs quite a bit cooler.

Fuse and Voltage

To meet the world-wide AC power specications, three different input power modules
are available. These are not switchable so Ampliers cannot be moved between regions
without changing the input module. The rest of the Amplier is identical.

• USA Model requires 120VAC +/- 10V, 50 or 60 Hz

• Japan Model requires 100VAC +/- 10V, 50 or 60 Hz

• International model requires 240VAC +/- 20V, 50 or 60 Hz

The amplier uses a 15A SLOW BLOW fuse. It is an input fuse only. The
amplier does not have output fuses.

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