The legendary sound of Ardent Studios now available with this ultra-limited edition Vari-Mu Compressor.

When you hear records made at Ardent, you are listening to the heart and soul of Memphis and from here on out, that spirit is captured by the HERCHILD Model 670: The Ardent Edition.

Ardent Recording Studios is one of the most iconic music studios in the world. Known for its creative energy and technological excellence, it’s been home to a wide range of unique and talented recording artists, producers, and engineers, and has witnessed the creation of many timeless recordings that have influenced the direction of modern music and music production.

So it is easy to understand that when Ardent Studios first contacted us to evaluate the possibility of having an Ardent Edition of our HERCHILD to substitute their original Fairchild units we could barely believe it. Since its release, the HERCHILD has stablished itself as the industry reference for “Vari-Mu FAIRCHILD” compression all over the world, but with this request from Ardent we now had a new challenge…a unique opportunity to take it to another level.


But, what is so special about the original Ardent’s Fairchilds? Ardent’s team modified the attack and release times of their original units in the early 70’s so that the time constants were faster and, therefore, more usable for modern recording studios at the time. This mods were first used to track Jimmy Page’s acoustic guitars on Led Zeppelin III and it is been a best kept secret… until today.

After receiving the pencil on paper notes from the original modifications, the Heritage Audio team has worked together with Ardent’s to nail the time constants of the original and after several months the HERCHILD “Ardent Edition” is a reality. Ardent’s team were so impressed by the performance of the HERCHILDs that they have changed their original FAIRCHILDs for four HERCHILD 660s and a HERCHILD 670.

Ardent’s specific 6 Attack and Release times have been exactly duplicated in the TIME CONST section as has its all-tube side chain circuit for precise control.

Direct access to the progressive ratio with the DC THRESHOLD, which is a unique curve adjustment combining control of the ratio and the knee. This is continually adjustable from hard limiting to very smooth and transparent compression settings.

The SC FILTER is a side chain filter with 4 selectable frequencies to reduce the lower frequency’s influence on the signal, a must have nowadays.

The HERCHILD Model 670 “The Ardent Edition”, being a 2 channel unit, also has the AGC section to determine which of the 4 modes it will work in. The 4 modes of operation to choose from are: IND, LINK, LAT VERT & LAT VERT LINK. IND gives you independent control for each channel while LINK, obviously, links the two channels operation together so both channels are controlled by taking the average from the two channel’s settings to determine what the overall stereo control will be.

The LAT VERT mode is originally from the days of using a cutting lathe to prepare vinyl records. It was crucial to carefully decide the depth and the width of the grooves, so you had precise control over both aspects in this mode. Nowadays, people have discovered the advantages of mixing and mastering with MID/SIDE processing as it allows you creative control over the center and side signals of a stereo track separately. LAT VERT is the equivalent to MID/SIDE and when used properly it really gives you the control to make your songs sound wider, deeper and more focused. And the last option is LAT VERT LINK and is again for MID/SIDE processing but this time with the two channels linked together and controlled by taking the average from the two channel’s settings to determine what the overall control will be.
  • Input Impedance: 2 kΩ.
  • Output Impedance: 600 Ω.
  • Output Level: +30 dBu clipping point.
  • Frequency Response: 20 Hz to 20 kHz ± 1 dB.
  • Signal To Noise Ratio: 120 dB.
  • Self Noise: Less than -82 dBu.
  • Harmonic Distortion: Less than 1% at any level up to +18 dBu output (no limiting).
  • Watts: >100W.
  • Dimensions (W x H x L): 482 mm x 134 mm (3 Rack units) x 200 mm.
  • Weight: 7.365 Kg.
Herchild-Model-670-The Ardent Edition_Side
  • Input Impedance: 2K Ω
  • Output Impedance: 600 Ω
  • Output Level: +30dBu clipping point
  • Frequency Response: 40Hz to 15kHz +/- 1db
  • Self Noise: Less than -82dBu
  • Harmonic Distortion: Less than 1% at any level up to +18dBu output (no limiting)
  • Dimensions (W x H x L): 482mm x 134mm (3 Rack units) x 200mm
  • Weight: 7.365 Kg
Customer Ratings