The Sequence
Source >
Preamplifier >
Amplifier > Speaker
and or TV / Projector
Source
An audio or video
source is the initial component of the sequence. Audio
and video sources include compact disc players, turntables,
DVD players, BluRay players, cable boxes, satellite
receivers, Internet streaming devices, AM/FM tuners, audio
cassette decks, game consoles, off-air television tuners,
Bluetooth devices, etc.
Each source has output jacks
that feed the input jacks of the next step in the sequence
via -- HDMI, single-ended RCA, optical Toslink, or balanced
XLR -- interconnecting cable. Wireless Bluetooth and
WiFi sources transmit to Bluetooth and WiFi receivers of the
next sequence step.
*Audio
or AV Preamplifier
The next step in the
sequence path is the audio and or audio/video preamp.
Sources enter the preamp via dedicated labeled input jacks
or wireless Bluetooth and WiFi receivers. The preamp
switches between connected sources via a knob or row of
buttons on the preamp front panel.
Prior to the exiting the
output jacks, selected sources are manipulated and or
processed via another knob, buttons, or the setup
menu.
Manipulation includes volume, bass/treble control,
equalization. Processing includes surround formats,
digital audio formats, video scaling, video
trans-coding.
The selected source is then routed to the next step in the
sequence.
Audio or Video Amplifier
The Audio Amplifier
The audio preamp output jacks
connect to the input jacks of the amplifier.
The amplified audio then continues to the speaker connecting
output jacks.
The Video Amplifier
The AV preamp video output
connects to the video input of a TV or projector.
Video amplification is integrated with the TV video decoding
circuitry.
The Speaker ...........
The amplifier output speaker
jacks are connected to the speaker input jacks.
The speaker modulating speaker cone that reproduces the
ultimate sound waves.

........ and or TV/Projector
The AV preamp output connects
(typically via an HDMI interconnect) to the TV or projector
input jack.
The combined output of the TV video decoder/amplifier
illuminates the pixel elements of the TV or projector.
Sequence confusion, audio
adjustment, and three additional notes.
1. TV Confusion
The television can add confusion. TVs include
additional input jacks plus
"The Sequence" of an off-air-TV-tuner source > switching
pre-amp > amplifier > speaker and TV screen.
This permits the TV to perform as a stand-alone low-fidelity
audio plus video system.
2. *Pre-amp Adjustment
Many audio pre-amps and receivers have eliminated the phono
preamp stage. If a turntable is in play, then a
dedicated-phono-pre-amp must be added and inserted to the
input of the pre-amp. The phono pre-amp boosts phono
cartridge voltage and provides RIAA specified playback
equalization.
3. Sequence Note
A stereo or AV receiver is a source AM/FM tuner + pre-amp +
amplifier in one cabinet.
An integrated amplifier is a pre-amp + amplifier in one
cabinet.
A portable radio is an AM/FM tuner + pre-amp + amplifier +
speaker in one very small cabinet.
4. Video Sequence Route Note
The video source determines the interconnect path to the
TV. Contemporary product is widely limited to HDMI
cabling. However, legacy product may employ composite
video, component video, or RGB interconnects. If you
start a sequence with composite video, then composite
cabling must continue to the TV. If component cable,
then component cable must complete the sequence.
Multiple types of cabling requires multiple hookup paths to
the TV, and video source switching, unless the
receiver/preamp includes video transcoding.
Typical transcoding converts composite and component video
to HDMI. However, transcoding has disappeared
from many current AV receivers. Therefore, ask
customers if they plan to use legacy video sources.
Then choose the appropriate receiver/preamp.
5.Interconnect Jack Note
Each sequence step described connection via outputs and
inputs jacks. Integrated devices (as in Note #3) are
connected on their PC boards.