Store; Original Value; Fx Loop; Tube-Safety-Control (Tsc) - Hughes & Kettner Switchblade TSC Head 100 Manual

6
4
Master
The Master section lets you adjust the amp's overall Volume, route external effects,
and store Presets.
4.1 MASTER
As its name would suggest, this knob puts the power to control the amp's overall
volume at your fingertips. Exercise restraint when handling this knob to make
music a pleasant rather than a painful experience.
Handling: Unlike the Channel and effect knobs, the MASTER knob is not
programmable! It works like any standard knob, and the position of the knob
indicates the actual setting.
Caution: High volume levels can cause hearing damage. Spare yourself a nasty
surprise and twist the MASTER knob to the far left-hand position before
powering the amp up.

4.2 STORE

Use the STORE button to save your Presets. See chapter 7.4 for more info.

4.3 ORIGINAL VALUE

This LED tells you which knob setting is stored in the given Preset. To this end,
select a Preset, grab the knob and twist it to the left or right until this LED lights
up. The setting at which the LED lights up corresponds to the setting stored in
the Preset.

4.4 FX LOOP

SmartLoop™ is a special effects routing circuit offering a switchable Parallel/Serial
effects loop for patching in external effect devices. Its status is stored in each
Preset, that is, whether it is on or off and configured in a parallel or serial circuit.
4.4.1 SERIAL
Switches the effects loop from Parallel (LED does not light up) to Serial (LED
lights up).
4.4.2 FX ON
Switches the effects loop on (LED lights up) and off (LED does not light up).
Tip: If you have not inserted an effect device into the FX Loop, you can use
this circuit for other purposes and store the configurations individually in each
preset:
• In parallel mode, you can use the RETURN jack to connect a second
instrument or any other audio source. You can also route the amp's signal to a
second power amp.
• In serial mode, the effects loop lets you control the amp's volume remotely by
simply connecting an analog Volume pedal to SEND/RETURN.
Caution: The signal chain is severed if the effects loop is configured serially
and no effect device is connected. Send is not the best to-mixer routing option
because it accesses the preamp signal only. Patch the power amp signal to a
mixing console via the Hughes & Kettner Red Box® and the speaker outputs.
5
Tube Safety Control (TSC)
TSC biases your power output tubes, ensuring they last longer and sound better.
It does this by setting their idle current to the correct value. Best of all, TSC does
this automatically, so there is nothing for you to do.
S w i t c h b l a d e T S C
It also offers some more hip features for dealing with different power output tubes
that are likely to interest you. If not, simply handle the amp as you would any
conventional tube amp. But on issues concerning tube replacement, please do read
and heed chapter 8, Replacing tubes, preventive maintenance, and service as well
as section 5.3.2, Checking for matching ratings when swapping tubes.
5.1. Why did Hughes & Kettner develop TSC?
We developed TSC to satisfy the demands of discerning
guitarists like you who aim to attain and sustain the best
tube-driven tone, enhance tubes' stability and extend their
lifespan, and enjoy the services of even more reliable amp.
Caution: We developed TSC exclusively for power output
tubes, and this chapter addresses only this type of tube.
5.1.1 What's up with bias, ratings, and matching?
The basics briefly explained. Bias is the amount of idle current flowing in the
tube grid when it receives no AC signal. So, biasing is the practice of setting the
idle current in an output tube. Tubes and their component parts are delicate,
and every tube's tolerances vary somewhat. Conventional amps must be biased
to match the given combination of power output tubes. If several tubes share the
same bias point or rating, we say they are matched. The golden rule is to always
use matched tubes in a guitar amp. This has the advantage that the tubes bear
an equal load, which reduces wear and extends tube life. What's more, it yields
better tone. Unmatched tubes in conventional amps don't operate at the optimum
bias point, so they wear faster, must be replaced sooner, and causes your amp to
generate undesirable noise such as crossover distortion, which degrades its tone.
5.1.2 The benefits of TSC:
No more manual biasing: If you swap out all tubes in conventional amps so that
their characteristic curve changes, you have to get a technician to re-bias the amp.
Not so with SWITCHBLADE TSC, because it biases the amp on its own. So
the amp always runs at its optimum operating point, which has both tonal and
technical advantages.
Best possible sound from tubes that no longer match: Tubes are very sensitive.
Even minor knocks can change their characteristics so they no longer match. But
thanks to TSC, tubes always run at their optimum operating point, even if outside
influences such as vibrations and the like change the bias point. If this happens
to a conventional amp, you will experience undesirable crossover distortion.
TSC minimizes this noise by automatically adjusting the bias to achieve the best
possible sound.
Less tube wear: Unmatched tubes in a conventional amp wear faster and must be
replaced earlier. TSC nips this problem in the bud by adjusting the bias of every
power output tube to the optimum operating point, sparing you and the amp in
further technical problems.
It indicates faulty tubes, yet allows you to keep playing the amp: In all but very
few cases, the amp remains operational despite a defective tube. All you have to
do afterwards is analyze the problem by simply looking at the Tube Status Control
LED to see if it flashes or lights up continuously (see section 5.2).
It lets you check power output tubes: You can check the tubes' status,
characteristics, and rating at any time (see chapter 5.3.1).
It lets you use EL34 and/or 6L6GC tubes: As an alternative, you can also use
6L6GCs, even in combination with EL34 tubes (see sections 5.3.2 and 5.3.3)

5.2 What TSC's Tube Status Control tells you:

The LEDs are key components of TSC. They tell you if:
- the amp is operating normally (see section 5.2.1)
- current is actually flowing to the power output tubes (see section 5.2.2)