Radial Engineering confirms its new Space Heater 500 tube overdrive unit is now shipping. The Space Heater 500 is a single-wide tube overdrive module for the Radial Workhorse and other 500 series racks that delivers natural crunch to drums, adds character to voice, and natural compression to bass and acoustic guitar.
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The new Radial Space Heater 500 is a studio-grade tube distortion for the 500 series format, built to provide anything from subtle warmth to thick and heavy harmonic distortion. Built around a 12AX7 tube, the Space Heater 500 features a drive control to determine the amount of signal passing through the tube, a three-position heat switch to apply 35, 70, or 140 V at the plate and change how the tube reacts to the signal; sweepable high-pass and low-pass filters assignable "pre" or "post" tube; and finally, an output level control providing attenuation or boost through an oversized Jensen transformer.
According to Radial product guru, Jay Porter: “When we launched the eight-channel Space Heater, it became immediately apparent that we had no choice but to make a module for our growing 500 series customer base. The Space Heater sounds huge and brings so much excitement to production, it will likely become one of those tools that you use each and every time you lay down a track.”
The design begins with a single-wide 500 series module in a fully enclosed steel enclosure. This not only protects the sensitive electronics but also helps prevent outside radiation from causing noise, or from the Space Heater 500 creating buzz, due to the high voltage required by the 12AX7 tube. This, in fact, is part of the magic. The three-position HEAT switch enables the user to choose between 35, 70, or 140 V for the desired level of tube distortion.
At the low 35-V setting the tube is starved for voltage which causes the tube to break up at a very low volume. The middle 70-V setting is a great starting point and enables the tube to handle more level before breaking up to a moderate distortion. At 140 V, maximum voltage is applied to the tube producing slight saturation and warmth.
Distortion is further adjusted using the combination of a drive control plus a level for make-up gain. The plate voltage is generated by an internal charge pump while the Workhorse or 500 series 16V supply provides the 12AX7 tube the 12 V needed for the heater. A Jensen transformer is employed at the output to bring a more vintage character to the signal path while benefiting from galvanic isolation to reduce hum and buzz caused by ground loops.
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To further refine the sonic response, the Space Heater 500 is equipped with both high-pass and low-pass filters. These allow to focus the tube effect on a particular frequency band or spread it out as needed. The EQ can also be applied to the signal path either pre or post tube for even greater tonal flexibility.
As the Space Heater 500 employs a high voltage tube circuit with a current draw of 235 mA, a special power allocation switch adjacent to the card edge connector is available to balance the draw for use with most 500 series racks.
MAP for the Space Heater 500: $699.99
www.radialeng.com