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Authentic tube mic preamp modeling
When Universal Audio founder Bill Putnam Sr. introduced the 610 Modular Amplifier preamp in the early '60s, it was a milestone in audio recording history. The 610 became famous among record producers for its startling harmonic detail, and rich clipping characteristics, and its ability to overdrive in a warm, ultra-musical fashion.
The original 610-A preamp was integral to countless legendary recordings — from the Beach Boys' Pet Sounds and Johnny Cash's At Folsom Prison. Its modern variant, the 610-B, helped to create new classics by Adele and Cold War Kids. Today, you can add the same tube presence, warmth, and body to vocals, guitars, bass and more with the UA 610 Tube Preamp & EQ Collection.
- Give your tracks startling three-dimensional tube warmth, presence, and body
- Use the 610-A plug-in to get the exclusive sound of the Wally Heider "Green Board," used to record Neil Young, Ray Charles, Elvis Presley and Jimi Hendrix
- Record "through" the 610-A or 610-B tube preamp models in real time using any Apollo interface that features mic preamps
- Get the character of the 610's entire signal path, including tube amplifiers and transformers, and circuit nonlinearities
- Mix and saturate signals for an iconic tube glow
- Control Apollo interface mic preamp gain staging and impedance directly from the plug-in via Unison™ technology
The First Genuine 610 Tube Preamp Emulation
With over three years of development, the UA 610 Tube Preamp & EQ Collection represents the first comprehensive modeling of the legendary 610-A tube preamp and its modern variant, the 610-B — including their tube and transformer components and all of the unique distortion characteristics of the originals.
The 610-A is modeled on a channel from the storied Wally Heider "Green Board," used to record Neil Young, Ray Charles, Elvis Presley and Jimi Hendrix, and offers simple 10 kHz high-shelf and 100 Hz low-shelf EQ. The modern 610-B offers selectable input impedance, adjustable high- and low-shelf EQ, and expanded gain range.
Unison Technology for Apollo Interfaces
With UA's Unison technology, the UA 610 Preamp & EQ Collection blurs the lines between analog and digital, giving you all of the 610's important impedance, gain stage "sweet spots," and circuit behaviors that have made it legendary.
And just like their hardware relatives, both the 610 plug-ins allow Line and Mic levels, with both 500 Ω and 2.0 k Ω impedance setting options available in the 610-B. Combined with Apollo's physical preamp gain, this provides a tonal range from clean to clipped — with tons of broad, musical sweet spots in-between.
Add Tube Color to any Source
UAD-2 and Apollo 16 owners can use the UA 610 Tube Preamp & EQ Collection for mixing, adding color and saturation to any source, without going outside the box. Inject your tracks with the legendary warm, natural compression the 610 is famous for, allowing you to place instruments perfectly in the mix while giving them a rich, three-dimensional tube character.
UA 610-A (left) and UA 610-B (right)
The UA 610 Plug-Ins
The UA 610 Tube Preamp & EQ Collection consists of two distinct plug-ins: The vintage UA 610-A, and the modern UA 610-B. Each plug-in has its own modeling and each captures its unique segment in the 610's sonic history.
The complete signal path is modeled for both 610 plug-ins, including tube amplifiers and transformer components, along with all the phase shift and distortion characteristics that are inherent in each hardware preamp.
Vintage 610-A
The original 610 Modular Amplifier had two versions; the 610 and the 610-A. Besides minor cosmetic differences (such as updates to the panel layout and the UA logo), the only circuit difference between the two was the addition of a +3 dB setting to the 10 kHz High Shelf EQ.
The UA 610-A plug-in models the vintage 610-A module in the original Wally Heider "Green Board" console.
Modern 610-B
The 610-B is the modern Universal Audio preamp design used in our popular hardware products such as the 2-610, LA-610mkII, and 6176.
The UA 610-B plug-in is modeled from the Universal Audio 2-610 Dual Channel Tube Preamplifier hardware, including all the expanded features optimized for modern use.
In Use
A primary use for either 610 plug-in is for individual vocal or instrument tracks where colorful tube character and broad EQ strokes are desired. The 610 is widely used as a vocal, bass, horn or strings channel by many modern users, but it sounds great on any source signals, as proven by over five decades of record making.
Tonal Range
From clean to clipped, with a broad sweet spot between, extreme tonal flexibility is possible with the 610-A and 610-B. The input and output circuits each have their own tube-driven gain stage, and because each stage imparts its own color, many variations can be obtained by tuning the I/O gain structures. The UA 610 equalizers can also add lots of flavor. Because the EQ has a feedback-style design, it effects the distortion characteristics of the output stage.
Presets
The UA 610 plug-ins include presets. You can access presets using the UAD preset browser.
Control Differences
The UA 610-A and UA 610-B plug-ins have similar controls and layouts.
For some parameters, the function of these controls is identical for both plug-ins. In the parameter descriptions below, controls and/or descriptions that are common to both plug-ins are detailed at the top of each control name section.
Any differences and/or controls that are unique to each specific plug-in are detailed after the common description.
Note: As with the original hardware, values on the control labels may not match actual measured values.
Apollo Unison Interactions
Some control descriptions begin with the Unison Interaction(s) heading. Descriptions in these sections apply only when the plug-in is placed in the dedicated UNISON insert on the Apollo preamp channel within Console or LUNA.
Note: When Unison plug-ins are used in standard (non-Unison) inserts, the Unison interaction descriptions do not apply.
For complete details, see the Unison chapter within the Apollo Software Manual (for rackmount and desktop models) or Apollo SOLO Manual.
Gain parameter outlines in Unison gain stage mode indicating hardware control is available
Input Controls
UA 610 input levels are adjusted with the overall combination of the input select, pad, and gain controls available within each plug-in.
These controls, which are different in the 610-A and 610-B, adjust the first tube gain stage. Generally speaking, higher input gains in the first tube stage will produce more color in the signal. The Pad is used to attenuate incoming signals for less coloration, while the Gain control increases the input signal level for more tube color.
Input Select
The 610 hardware has both mic and line level inputs. When used with a DAW, the Input Select control switches between the "virtual input jacks" in the emulated preamps.
Tip: Click the text labels to change the settings.
Important: Use caution when switching to Mic from Line, as signal output levels can increase significantly (as they would with a hardware preamp).
Unison Interaction |
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Software and hardware controls are mirrored and bidirectional, and can be adjusted with the plug-in, Console/LUNA software, or Apollo's hardware INPUT switch. When Apollo's Hi-Z instrument input is connected, the source switch is automatically overridden and the switch has no effect. |
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Line
When set to Line, it's as if the DAW signal is plugged into the line level input of the emulated 610 hardware. Less tube gain is applied, and a cleaner sound is obtained.
Mic
When set to Mic (with UA 610-B, when 500 or 2.0K is selected), it's as if the DAW signal is plugged into the microphone input of the emulated 610 hardware and approximately 30 dB of additional (unattenuated) tube gain is applied. Since the incoming signal in from the DAW is already at line level, this mode will more readily result in the tube color, saturation, and/or clipping associated with overdriving the input.
610-A Mic Impedance
The mic input impedance of the 610-A hardware is 600 Ohms.
610-B Mic Impedance
The Mic input can be switched to 500 or 2K Ohms; the different input impedances have subtle effects on the signal color and response.
Unison Interactions |
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The hardware input impedance of the Apollo mic preamp is switched to match the value in the plug-in for physical, microphone-to-preamp resistive interaction. With UA 610-B, matching the microphone to the closest impedance value is generally recommended, but this parameter can be used creatively and will not harm equipment connected to the Apollo mic preamp. |
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Input Gain
The Pad and Gain parameters both control the signal level at the tube input stage. The Pad controls are used to attenuate incoming signals for less coloration, while the Gain controls increase the signal level for more tube color.
Tip: Click the text labels to change the settings.
Unison Interactions |
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Software and hardware control is mirrored and bidirectional, and can be adjusted with the plug-in, Console/LUNA software, or Apollo's hardware PREAMP knob. When Apollo is in Unison Gain Stage Mode, the control is outlined in orange, indicating it is available for hardware control. |
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610-A Input Gain
The three-position LO/OFF/HI rotary switch exposes the little-known internal gain jumpers that are on the circuit boards inside the vintage modules.
Setting the switch to the HI position adds approximately 8 dB of gain at the tube input stage and also changes the distortion characteristics. This is a digital-only control unavailable on the original hardware module.
When Input Gain is set to OFF, the plug-in is bypassed and DSP usage is reduced (if DSP LoadLock is inactive). This control has the same function as the OFF position with the Output Level knob.
610-B Input Gain
The 5-position rotary Gain switch changes the level at the tube input stage, and also changes the distortion characteristics. The control attenuates the input signal by -10 or -5 dB, or adds +5 or +10 dB of gain. In the center "0" position, neither gain nor attenuation is applied.
Mic Input Pad
Additional attenuation for the Mic input is available via the two-position Pad switch. Setting the switch to the up position attenuates the Mic signal at the tube input stage. In the down position, no attenuation is applied.
610-A has -20 dB attenuation available, while 610-B has -15 dB attenuation available.
Note: The Input Pad is not available for line input.
Unison Interactions |
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Software and hardware control is mirrored and bidirectional, and can be adjusted with the plug-in, Console/LUNA software, or Apollo's hardware PAD switch. In Unison mode, PAD is unavailable with Line and HI-Z inputs. |
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Polarity
This switch inverts the polarity (aka "phase") of the signal. The signal polarity is inverted when the switch is in the up position. Polarity is normal when the switch is in the down position. Polarity inversion can help reduce phase cancellations when more than one microphone is used to record a single source.
Tip: Click the text labels to change the setting.
Unison Interaction |
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Software and hardware control is mirrored and bidirectional, and can be adjusted with the plug-in, Console/LUNA software, or Apollo's hardware ø switch. |
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EQ Controls
The UA 610 preamps feature high and low frequency boost/cut shelving filters with stepped gain controls. The equalizers utilize a feedback-style design which effects the distortion characteristics of the output stage.
Tip: Click the text labels to change the settings.
610-A EQ
The 610-A EQ has low frequency (L.F.) and high frequency (H.F.) shelf filter bands that can be cut or boosted by various amounts. The rotary switches determine the amount of boost or cut applied to the low and high filter bands. When set to 0 dB, the filter band is inactive.
L.F. Gain
The low frequency (L.F.) shelf EQ has a fixed cutoff frequency of 100 Hz. Fixed gain values of ±6 dB or 0 dB can be selected.
H.F. Gain
The high frequency (H.F.) shelf EQ has a fixed cutoff frequency of 10 kHz. Fixed gain values of -6, 0, +3, or +6 dB can be selected.
610-B EQ
The 610-B EQ has low (LO) and high (HI) shelf filter bands with selectable cutoff frequencies that can be cut or boosted by various amounts.
LO Frequency
This switch determines the cutoff frequency (70, 100, or 200 Hz) of the low shelf EQ. This switch has no effect if the Lo EQ Gain value is zero.
LO Gain
This rotary switch determines the amount of boost or cut applied to the low frequency signal. Fixed values of plus or minus 9, 6, 4.5, 3, or 1.5 dB can be selected. When set to 0 dB, the filter is inactive.
HI Frequency
This switch determines the cutoff frequency (4.5 kHz, 7 kHz, or 10 kHz) of the high shelf EQ. This switch has no effect if the Hi EQ Gain value is zero.
HI Gain
This rotary switch determines the amount of boost or cut applied to the high frequency signal. Fixed values of plus or minus 9, 6, 4.5, 3, or 1.5 dB can be selected. When set to 0 dB, the filter is inactive.
Output Controls
Level
Level (aka "the big knob") is used to control the gain of the tube output stage of the preamp. Higher values add more coloration.
The amount of available gain using this control is approximately 61 dB for both plug-in models.
Unison Interaction |
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When Apollo is in Unison Gain Stage Mode: Software and hardware control is mirrored and bidirectional, and can be adjusted with the plug-in, Console/LUNA software, or Apollo's hardware PREAMP knob. The control is outlined in amber, indicating it is available for hardware control. |
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Output / Off
Output
Output is a clean gain control adjusts the signal level at the output of the plug-in without effecting the sonic character of the signal. The range is from -∞ dB (off, but DSP still loaded) to +12 dB.
Tip: Click the "0" label text to return Output to 0 dB.
This control, which does not exist on the original hardware, facilitates the ability to maximize color of the overall signal. For example, Gain and Level can be cranked for more distortion, while lowering Output to normalize levels. This is similar to having the line output of a 610 plugged into a console and using the console fader to pad the output of the 610.
Unison Interactions |
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When Apollo is in Unison Gain Stage Mode: Software and hardware control is mirrored and bidirectional, and can be adjusted with the plug-in, Console/LUNA software, or Apollo's hardware PREAMP knob. The control is outlined in green, indicating it is available for hardware control. |
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Off
When Output set to OFF, the plug-in is bypassed and DSP usage is reduced (if DSP LoadLock is inactive). This control has the same function as the OFF position on the Input Gain switch.
Tip: Click the OFF text label to disable the plug-in. The OFF position cannot be set by rotating the output knob unless Gain Stage Mode is active.
610 History
Creating an original 610 desk meant buying the individual modules and building the console from scratch, as no complete consoles were ever sold commercially. However, Bill Putnam himself built a few full-fledged desks for his own studios, complete with fabricated frame, power supply, metering, and bus/effects routing options.
Although very few desks were built from 610 modules, their contribution to the history of recorded music is enormous. Ray Charles, Frank Sinatra and The Beach Boys were a few artists captured with the 610 at United/Western as part of landmark recordings such as "Sounds in Country and Western Music," "Strangers In The Night," and "Pet Sounds," respectively.
One of these 610 desks is the famous Wally Heider "Green Board." This extremely well-built example was originally fabricated by Frank DeMedio for Wally Heider's Remote Recording Service in the early `60s. Wally originally handled many of the live recording dates booked by Putnam. This console recorded and mixed some of the greatest performances of the era, from many live shows with the "Rat Pack," to recording the very last concert under the baton of Igor Stravinsky in Los Angeles.
With the Wally Heider Green Board alone, the list of records using the 610 is staggering. Here are but a few notable acts recorded with the Green Board: Duke Ellington, Elvis Presley, Johnny Cash at Folsom Prison, Fats Domino, Little Richard, Cream, The Beach Boys, The Doors, Janis Joplin with Big Brother & The Holding Company, The Who, The Grateful Dead, The Steve Miller Band, Moby Grape, The Byrds, Jefferson Airplane, Booker T. & the M.G.s, Otis Redding, Eric Burdon and The Animals, Simon and Garfunkel, and The Jimi Hendrix Experience (live at the Monterey Pop Festival, where he first set his guitar on fire!).
In the early '70s, long before this one-of-a-kind desk's historical significance could be anticipated, Neil Young bought the 12-channel board from Wally Heider. Young immediately moved it to his Broken Arrow Ranch. He installed the desk in his barn, which he used as a recording studio, and employed it to record his seminal record "Harvest" and may other classic albums. The Green Board remains at Broken Arrow Ranch, and is still in use today.
The Universal Audio 2-610 Dual Channel Tube Preamplifier