The Chandler Limited REDD.47 Mic Amplifier is a faithful recreation of the original tube line amplifiers used in Abbey Road’s EMI REDD.51 console with additional features for modern recording standards.
It’s a fairly common practice for manufacturers whose equipment was used in famous recordings to claim their unit as “the sound of The . . . ” when in reality it was just a part of a much larger signal chain, which in turn has an effect on the unit in question. In essence, you could say that no preamp is an island unto itself, but there are always exceptions, a notable one being the original REDD.47, which actually did determine the sound of The Beatles, and not just as part of a signal chain. (More on that later). Originally designed as a modular replacement for the extremely rare and rich-sounding Telefunken V72, which was the key sonic factor for the Abbey Road consoles preceding the REDD.51, the REDD.47 mic amp actually did become integral to the sound of Abbey Road. The REDD.47 lent its unmistakably punchy and aggressive character to music recorded at Abbey Road Studios' Studio Two between 1964 and 1968, including many tracks by The Beatles. Updated for the modern age, the Chandler Limited REDD.47 offers even more tonal options.
Chandler Limited REDD.47 Mic Amplifier—Just the Facts:
- Recreation of the original tube line amplifiers used in Abbey Road Studios’ heralded and rare EMI REDD.51 recording consoles circa 1959-1968
- Expanded voltage gain over the original
- Fine Gain Set offers an expanded range of ±5dB available in 1dB increments over the original REDD.47
- Variable output gain control acts as a channel fader
- Low-cut rumble filter featuring eight frequency settings from 30-180Hz
- Easily reproduces the guitar distortion heard on The Beatles’ “Revolution.”
Chandler Limited REDD.47 Mic Amplifier—Under the Hood
Designed as a central component to the EMI REDD.51 recording console, the original REDD.47 line amplifier was used to amplify virtually every stage of the audio path (mic inputs, line inputs, echo sends and monitors). The Chandler Limited REDD.47 Mic Amplifier offers many additional benefits to the original design including increased gain, allowing a range of tonal options from pristine clean sound to classic rich, saturated tone with up to 2% harmonic distortion before clipping. The Chandler Limited REDD.47 preamp easily reproduces the distortion heard on John Lennon’s guitar on The Beatles’ “Revolution.”
Chandler Limited’s REDD.47 tube microphone preamplifier delivers the legendary sound of Abbey Road Studios’ “Holy Grail” preamp, with extra features to meet today’s recording studio standards.
The Voltage Gain control is a stepped input gain switch in 6dB increments. The gain range available from this control is expanded to 16dB-52dB over the original REDD.47’s 34dB, 40dB, and 46dB. Use this control to set the desired input gain. An additional ±5dB input gain is available via Fine Gain Set.
Fine Gain Set
The Fine Gain Set control is a stepped switch allowing for fine-tuning of the input gain. The Fine Gain Set offers an expanded range of ±5dB available in 1dB increments over the original REDD.47 line amplifier. When Voltage Gain and Fine Gain Set are set fully clockwise at the highest settings, the total input gain is 57dB.
The original Rumble Filter was a filter circuit available via jumper on the REDD.51 console. It was both unique in circuit design and function, rolling off bass at 30Hz. The Rumble Filter of the Chandler REDD.41 control is a low-cut mechanism, featuring eight frequency settings (30, 45, 60, 70, 90, 110, 130, 180Hz.) The Rumble Filter may be fully disengaged from the amplifier by setting it to “Out.” This feature is useful for removing unwanted low-frequency information from the signal. The Rumble Filter only works upon signal applied to the XLR input.
The Output control is variable and acts as a fader would on a console. It controls the overall output level of the pre-amplifier to your recording device or DAW, enabling you to “hit” the input of the REDD.41 harder for more saturation while protecting you’re A/D converter from overload.
A 20dB pad is included to tame hot sources applied to the mic-input XLR jack. The pad is handy for taming hot signals or using the REDD.47 for line level sources. To add rich harmonic texture to a digital mix, you can use a pair of REDD.47 Mic Amplifiers on your mix bus. If you’re using the REDD.47 on your mix bus, turn down your DAW’s master fader enough not to distort the REDD.47’s input (you might not need the pad either), then turn up the Voltage Gain and use the Fine Gain Set to dial in the right color, then let the REDD.47 do its job: Amplify.
The EMI/Abbey Road Studios REDD.47 line amplifier was first conceived in 1958 as a replacement all-purpose line amplifier cassette for the Telefunken/Siemens V72s used in early REDD mixing consoles.
In 1958, EMI and Abbey Road Studios, through their REDD (Record Engineering Development Department) division, set out to design the next-generation REDD mixing console, the REDD.51. The REDD.51 would be the last of the tube-based mixing consoles built by EMI, and the only one to use the REDD.47 line amplifier, making it that much more unique.
The first REDD.51 console was manufactured in 1959. However, it wouldn’t be until 1964 before a REDD.51 console was installed at Abbey Road Studios’ Studio Two, home to the Beatles. The REDD.51 console and its REDD.47 line amplifiers left their unique and exceptional sonic character on Beatles records recorded at Abbey Road Studios’ Studio Two during 1964-1968; the majority of the Beatles’ catalog.
Only four REDD.51 consoles were built, none of which have resurfaced after Abbey Road sold off its old equipment in the ’70s, though one sits unused in a private collection in Italy. Hence, if you want the sound of the REDD.51’s REDD.47 preamps, you’d be completely out of luck—but not any more—thanks to Wade Goeke’s Chandler Limited REDD.47. As an aside, with tubes being replaced by transistors in the ’70s, EMI began work on the TG consoles, which replaced the REDD. (Chandler also makes TG channels, but you probably knew that already.)
Start a Revolution
One of the most unique and iconic guitar sounds is heard on the Beatles song, “Revolution.” As we previously mentioned, the REDD.47 is the exception to the rule regarding “being the sound of the Beatles.” In point of fact, John Lennon’s guitar sound was created solely with the REDD.47 (well, two actually) and without the use of a guitar amplifier. You can achieve this sound by plugging directly into the line amplifier, overdriving one REDD.47 into another. (Not trying to put anything over on you—you’re going to want two REDD.47’s regardless.)
If you’re looking for the legacy sound of ’60s Abbey Road and The Beatles, the Chandler Limited REDD.47 tube microphone preamplifier is one of the very few devices that can truly deliver. For more information, call or chat online with your PAD Studio Specialist, or order yours online today.
- Channels: Mono
- Circuit: Tube (EF86, E88CC)
- Inputs: Mic/Line XLR (pin 2 hot), DI (1/4")
- Output: XLR (pin 2 hot)
- Transformer balanced I/O (custom-wound)
- Voltage gain: Stepped 16-52dB
- Fine gain: Stepped ±5dB
- Total Gain: +57dB
- Output control: Variable
- Rumble filter: Inductor-based, switchable (30,45,60,70,90,110,130,180Hz)
- Pad: 20dB, switchable
- Phase: 0/180º, switchable
- Phantom Power: +48v, switchable
- Internal power supply