I'VE HEARD THAT THERE IS A RULE FOR NAMING CONVENTIONS OF
POWER AMPLIFIERS AND PREAMPLIFIERS...


Date: October 20, 1998 03:05 PM 
Author: julian vereker 
Subject: Yes 

I'm sure we put this info somewhere . . . 

NAC 52 - Naim Audio Control (model No) 5 2 (channel) 

NAP 250 Naim Audio Power (125 watts + 125 watts into 4Ohms continuous)
= 250

etc. 

julian 




IF NAIM IS SO MINIMALISTIC, WHAT IS THE REASON FOR KEEPING A BALANCE
KNOB? MOST OF OTHER MANUFACTURERS DO NOT PUT IT. CAN I GET RID OF IT?


Date: April 27, 1999 02:33 PM 
Author: julian vereker 
Subject: balance 

The connection and correct value of balance control is rather
important to the correct signal conditioning (safe driving of the
power amp) that the preamp does.

julian

PS Less is not always more. 



Date: March 24, 1998 02:03 AM 
Author: julian vereker 
Subject: balance control 

>>> I suppose Julian will tell us that all pre-amps feature the
balance control as an intrinsic part of the circuit,
and its removal would send the thing into oscillation. <<<< 

Exactly so. 

julian 

PS, I suppose that a bit of history comes in here, in the early
days Linn found it very difficult to make speakers with the same
sensitivity, and I can't tell left from right (hence ch.1 & ch.2),
so the balance control was pretty useful - and then in 1983 when
we introduced the NAIT in which the balance control only changed
the balance by +/- 3dB there was a general outcry.

Also, from a performance point of view, it doesn't matter whether
the control is there or not there as long as the circuit is designed
for its inclusion or not.




WHAT CLASS ARE NAIM AMPS? AUDIO MAGAZINES STATES THAT CLASS A IS
THE BEST...


Date: March 29, 1998 03:55 AM 
Author: julian vereker 
Subject: Bias 

All Naim power amps are class B and they have as low a bias as we
can manage, just a few milliamps.

There are two reasons for doing this, in order to make a good
push/pull power amp, the two halves need to match very closely
since there is only one common feedback loop - this applies whatever
the 'class' of the amp. If one achieves this degree of precision
then one only needs a very small bias current.

Also it is extremely wasteful of resources making class A power
amps, since they use large amounts of electricity even when they
are not playing music, this means the waste heat has to be dissipated
into the atmosphere without overheating the components and thus
shortening their lives, which implies large heatsinks, big heavy
and expensive in terms of resources pieces of equipment.

There are quite a few power amps about, that are called class A
for marketing reasons, but are in fact to all intents and purposes,
class B. (Save the planet - buy class B).

julian 



Date: April 19, 1999 02:44 AM
Author: julian vereker
Subject: Cliff

Just a quicky - Naim pre-amps are class A and therefore the current
stays pretty constant (except when switching on the relay switched
ones).

[...]

julian



Date: April 01, 1998 01:22 AM
Author: julian vereker
Subject: EW


D Self's writings (along with several other 'experts') in EW were one
of the reasons for cancelling my sub.

The guys who write in the mags on the subject of audio design, do it
with such certainty and I (we) know that it just isn't like that.

For example they never seem to discuss the PCB which is as important a
part of the circuit as anything else.

All our preamps are single ended class A (mainly for noise
considerations and of course, simplicity)

julian

PS I may be being unfair, but isn't there a saying "Those who can, do
and those who can't, write about it".




I CAN HEAR HISS ON MY FRIENDS' NAIM HI-END SYSTEM WHEN NOTHING IS
PLAYED. THIS IS RIDICULOUS!


Date: February 21, 1998 05:11 AM
Author: julian vereker
Subject: hiss

The hiss from the speakers is quite normal, specially when the phono
input is selected.

There are two issues, one: the DBLs are very efficient compared to
most other speakers and therefore the hiss will sound about twice as
loud as it would for the same volume setting using other speakers.
(and the music would also be about twice as loud if you happened to be
playing music rather than listening to the hiss).

Second: the way that our pre-amps are designed, the noise is such that
it is always masked by the noise from the source, ie the background
noise off vinyl (the worst case) is some 6dB noisier than the pre-amp
noise.

The 52 has a remote control - try reducing the volume or pressing
'mute' to reduce the hiss when not listening to music.

julian