ECC83 and one ECC82 preamplifier valves. The input accommodates both active and passive bass pick-ups; there is also an XLR DI output for recording complete with Earth (grounding) lift and Pre/Post EQ switches. In 2008, Marshall honoured Lemmy Kilmister of Motörhead with their first-ever signature bass amplifier head, based on his 100 watt super bass unit "Murder One". There are also solid-state models called MB series ranging from 15 watts to 450 watts and extension cabinets. CODE series In 2016, Marshall introduced the CODE series of modelling amplifiers, ranging from the 25-watt Code 25 (single 10-inch speaker), 50-watt (single 12-inch speaker) to the 100-watt Code 100 (available as either a 2×12-inch combo or as a head unit). Developed in conjunction with Softube, the amplifiers contain 14 MST preamps, 4 MST power amps and 8 MST speaker cabinets, along with 24 effects. The amplifiers can be controlled via Bluetooth from iOS and Android devices and can also be used to stream audio from a PC. Origin series A series of low-wattage, all valve heads and combos assembled in Vietnam hearkening back to the "Plexi"-era of the company. The Origin series was introduced to address a demand for lower volume amplifiers that many guitarists were calling for. To address this, Marshall announced the Origin5, a 5-watt amplifier that can run on either high (5-watt) or low (0.5-watt) with the help of Marshall's Powerstem technology. With the introduction of the Powerstem technology, the Origin amplifiers are able to provide reduced output power while retaining the same tonal characteristics of a full-powered amplifier. This is accomplished through the new attenuation system, Powerstem, by dynamically reducing the rail voltages throughout the amplifier. The Origin line consists of the Origin5 combo (5-watt, 1 x 8" Celestion Eight-15 speaker), Origin20 combo (20-watt, 1 x 10" Celestion V Type), Origin20 head, Origin50 combo (50-watt, 1 x 12" Celestion G12N-60 Midnight 60 speaker), and Origin50 head. Model number confusion Occasionally confusion has arisen due to Marshall's method of naming each amplifier model, especially during its first few decades, when it was distributed under Rose-Morris. Early amplifier models were simply named after their catalogue number, so for example the 1962 Bluesbreaker was item one thousand, nine hundred and sixty-two in the Rose-Morris catalogue. Later amplifiers were given range designations as well as model numbers, which often indicated information about the amplifier itself, for example the JCM2000 range of amplifiers had