Hey vaystrem, this is the whole message...
Thank you for your recent request via the NAD Electronics web-site.
In light of the fantastic review that we had for the C352 from What Hi Fi,
there have been a couple of consumers and dealers raise a question regarding
how to tell the difference between the old and the "new, improved" version.
So for the record, here it is. All units for sale in both Grey and Titanium
are the new improved version.
What Hi Fi reviewed a prototype model of the c352 in June last year and
gave it a three star rating. As a result of this, NAD made some subtle
changes to the design. All our customers have the "new, improved" version.
The "CT" referred to in the text is reference to the colour only, if you
note the text beside the picture you will see that it is still labelled as a
C352. Titanium is not available in North America.
The changes made to the unit are as follows:
We improved the DC servo circuit which tightens up the bass response. In a
complementary amplifier design, the positive and negative halves of the
waveform are handled by different "complementary" transistors - the gain of
each half of the circuit must be perfectly balanced or there will a DC
voltage present at the speaker outputs. With the original C352s, this DC
offset could drift in and out of perfect balance. When out of balance the
sound would not be to spec., especially noticeable in the bass region
performance. The "fix" was to add a high speed servo circuit that always
keeps the DC offset at zero. In point of fact, all C352's sold to the
public include this circuit."