Featuring twin-channel operation, selectable multi-impedance compatibility and true continuous attenuation, Reload II is our most advanced Load Box to date. In this article, we summarise some key information relating to what a Load Box is, setup considerations and some commonly asked questions to help you get the best out of your Torpedo Reload II device.

What is a Load Box?

In routine use of a tube amplifier, it is highly recommended that the power output of the amplifier is always connected to a speaker cabinet or suitable load prior to powering on. The speaker cabinet (rated at either 4-, 8- or 16-Ohms) must always be connected to the corresponding speaker output of the amplifier. Neglecting to do so can lead to partial or complete destruction of the output stage of the tube amplifier.

The majority of tube amplifier designers protect their products with fuses or alternative suitable protection systems; however, some amplifiers are still insufficiently protected. It is therefore impossible to predict the behavior of all amplifiers on the market in relation to the instantiated load (be it a speaker cabinet or a Load Box).

The electronic term that describes the speaker cabinet with respect to the amplifier is the “load”: we say the cabinet “loads” the amplifier. The term “Load Box” is used to describe any product that provides a load to the amplifier. The main parameter of the Load Box is its impedance, expressed in Ohms. Impedance matching between a Load Box and amplifier is paramount and as such should be actioned wherever possible (i.e. an 8-Ohm Load Box must be plugged to the 8-Ohm speaker output of the related amplifier).

The power sent by the amplifier to the corresponding load is turned into heat; as such, it is vital to refer to the cooling recommendations stipulated in the manual of the respective load; overheating may cause damage, both to the Load Box and to the amplifier.

Warnings & Setup Considerations

The following details our suggested considerations when configuring your Load Box into your live- or studio-backline:

• Always connect the speaker out of your tube amplifier to an appropriate load (speaker cabinet or Load Box). Reload II, once powered, is such a load. Always power on Reload II before your amplifier. The maximum admissible power of Reload II is 200W RMS
• Always ensure the impedance rating of your amplifier’s speaker output is matched to the AMP IMPEDANCE setting on Reload II; failure to ensure a correct match may result in irreversible damage to your amplifier or Load Box
• Always use a Speaker Cable for connections between the amplifier’s speaker out and Reload II’s AMP IN. Always use a Speaker Cable for connections between the Reload II’s CAB OUT A/B and any connected cabinets. Using an Instrument Cable instead of a Speaker Cable can cause significant damage to your amplifier or Reload II, ultimately requiring service by a qualified technician. If unsure about the classification of your cabling, please seek advice from a qualified specialist
• Only connect traditional guitar or bass cabinets to Reload II’s CAB OUT A/B connectors; for active speaker connections please use Reload II’s LINE OUT A/B XLR ports.
• Reload II’s CLIP indicators on CHANNEL A or CHANNEL B light up red whenever the signal is too strong. If preset, please lower the volume at the corresponding input

Setting the Output Volume for an Amplifier

The correct use of an amplifier with a Load Box requires caution. Due to the inherent silence while playing through an amplifier with a Load Box, it is easier to accidentally run the amplifier beyond the reasonable limits set by the manufacturer - more so than when using a speaker cabinet in conjunction with the amplifier. This can lead to faster tube wear and, in some cases, damage to the amplifier or Load Box.

When testing the amplifier at high volume, monitor the color of the tubes and the general state of the amplifier. Red-glowing tubes or any appearance of smoke are signs of a problem that may result in partial or complete destruction of the amplifier.

Please note that the “sweet spot” - the optimal level of the amplifier’s power amp volume - is rarely obtained at maximum volume. In addition, the volume control of the amplifier is usually logarithmic, meaning the volume increases quickly within the first half of the accompanying potentiometer’s rotation, reaching its maximum at 12 o’clock, Therefore, maximum volume of the amplifier can be reached even if the volume potentiometer is not set at its maximum value.

When reaching the maximum value of the aforementioned output potentiometer, you will likely hear considerable distortion. In fact, most amplifiers sound comparatively poor at maximum volume. In addition, always keep in mind that your amplifier may not have been conceived to be used at maximum volume for a long period of time. Running an amplifier at high volume will cause premature wear of the tubes and possible malfunction or damage at the output stage.

Setting your amplifier’s master volume to maximum may result in irreversible damage to your amplifier or Load Box. The fact that the volume control of your amplifier is not set at maximum does not mean your amplifier is not running at maximum volume - as such, we advise setting the output of the companion amplifier to a volume configuration you would use in a rehearsal or on stage.

Is the use of a Load Box Totally Silent?

The term “silent recording” is often used when a Load Box is involved. If we compare a Load Box solution to a traditional cabinet miking solution, the results are considerably quieter and controllable in terms of audible sound output. Noises that you may not have been able to hear before (due to the overbearing volume of the speaker cabinet) may become more apparent. Below is a non-exhaustive list of those sounds that may be heard when using an amplifier in tandem with a Load Box for silent recording purposes:

• Your guitar or bass strings can be heard. If you are not used to this, it could be initially distracting, depending on the environment
• You may hear some noise coming out of your Torpedo Reload when playing, akin to a small speaker inside the device. This is perfectly normal and there is no reason to worry. The sound is produced when power runs through the coil of the reactive load embedded within the Torpedo Reload II. The vibration is related to the power stemming from the amplifier connected to the Torpedo Reload II and to the signal’s frequency content (i.e. the pitch of notes played are heard). Your amplifier - specifically the output transformer of your amplifier - may also produce similar noise. Such noise is usually not heard, simply because it is often obscured by the sound stemming from a loudspeaker in traditional amplifier and cabinet setups
• Torpedo Reload II features a built-in fan as there is significant power dissipated into heat inside the device. The fan provided is marked as a “silent fan”, but as it is running fast, it is never entirely silent. With this said, in normal use (i.e. hearing your DI Signal through monitors or headphones), the fan is barely audible.

Does Torpedo Reload II Need to be Powered to Function as a Load Box for my Amplifier?

Yes. Reload II will only function as a reactive load for your amplifier when powered. When Reload is off, the amp is placed on a safety load of 270 Ohms to avoid any damage to the amplifier.

If Setting Reload II’s CHANNEL Input Selector Switches to Line, Will My Amplifier Still See the Load of Reload II.

It will indeed! Reload II’s Load Box circuitry is placed before any channels or channel routing facilities, ensuring any amplifier connected is always presented with a suitable load.

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