darTZeel Audio NHB-108 B version User Manual
Page 4

darTZeel NHB-108 model one
User Manual, version B 1.0
Page 4 of 35
Technical Section
T1. Introduction .....................................................................................................18
T2. Genesis of NHB-108 ........................................................................................18
T3. Criteria..............................................................................................................19
T4. Structural aspects ...........................................................................................19
T4.1. The
case modules ......................................................................................................................... 19
T4.2.
Divide to conquer......................................................................................................................... 20
T4.3. Eliminating
vibrations.................................................................................................................. 20
T4.4. Everything
is
transparent..................................................................................... 20
T4.5.
TIO, Totally Identified Object ..................................................................................................... 21
T5. The audio electronics......................................................................................21
T5.1. What
is
distortion? ....................................................................................................................... 21
T5.1.1. Keeping
in
harmony..................................................................................................................... 21
T5.1.2. Inter
Modulation Distortion ......................................................................................................... 22
T5.1.3. Temporal
Distortion..................................................................................................................... 22
T5.2. What
application field? ................................................................................................................ 23
T5.2.1. IGBTs........................................................................................................................................... 23
T5.2.2. FETs............................................................................................................................................. 24
T5.2.3. Bipolars........................................................................................................................................ 24
T5.3.
The circuit of darTZeel ................................................................................................................ 24
T5.3.1. Criteria of choice.......................................................................................................................... 24
T5.3.2. darTZeel
schematics .................................................................................................................... 25
T5.3.3. Component
layout........................................................................................................................ 25
T5.4. Symmetrically
balanced? ............................................................................................................. 26
T5.4.1. From the microphone… ............................................................................................................... 26
T5.4.2. To the loudspeakers… ................................................................................................................. 26
T5.4.3. And into the air… ........................................................................................................................ 26
T5.4.4. Via
the darTZeel .......................................................................................................................... 27
T5.5. darT
to Zeel 50Ω.......................................................................................................................... 28
T6. Onboard safety ................................................................................................29
T6.1. Crowbar
circuit ............................................................................................................................ 29
T6.1.1. Crowbar activation....................................................................................................................... 29
T6.1.2. Crowbar
cycle .............................................................................................................................. 29
T6.2. Supervision
system ...................................................................................................................... 30
T6.2.1. Current
sensing ............................................................................................................................ 30
T6.2.2. For
its eyes only ........................................................................................................................... 30
T7. Power supplies ................................................................................................30
T7.1.
From mains to loudspeakers......................................................................................................... 30
T7.2.
Voltage or current?....................................................................................................................... 31
T7.3. Received idea ............................................................................................................................... 32
T8. The sound of darTZeel ....................................................................................32
T9. Reliability .........................................................................................................32
T9.1. Quantified longevity .................................................................................................................... 32
T9.2. Long
term availability.................................................................................................................. 33
T9.2.1. Spare
parts.................................................................................................................................... 33
T10. The next darTZeel............................................................................................34
T11. Keeping an open door.....................................................................................34
T12. Special adjustments........................................................................................35
T12.1. Output DC voltage drift ............................................................................................................... 35
T12.2. Monitoring circuit ........................................................................................................................ 35