Name: Heritage Audio Herchild HA670 "Ardent Edition" Stereo Tube Compressor
Brand: Heritage Audio
SKU: Herchild670
Price: 308000000 VND
Availability: InStock

Heritage Audio’s Amazing Hot-Mod 670

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For over six decades, recording, mastering, and broadcast engineers alike have coveted the grandaddy of limiter/compressors, the iconic Model 670. This reverence is due to its inimitably smooth, creamy, and natural-sounding dynamics control, which can be heard on countless classic recordings. Less than 1,000 were ever built, and today, they are exceedingly rare — even more so if you’re seeking one in good working condition. If you can find a suitable Model 670, it will command a hefty price commensurate with its 66-pound curb weight. Fortunately, Heritage Audio launched its Herchild Model 670 in 2023 at half the price (and weight) of a functioning vintage 670. Now, the company has released the Heritage Audio Herchild Model 670 Ardent Edition stereo limiter/compressor, which incorporates modifications performed by the engineers at Ardent Studios in Memphis in the early 1970s.

A very special, limited-run Herchild 670

As impressive as the original 670 was, the engineers at Ardent Studios saw fit to modify their units to bring them up to date with the rapidly advancing studio technology of the era. These modifications had their baptism of fire when Ardent’s modded 670s were used on Jimmy Page’s acoustic guitar tracks for Led Zeppelin III. The results speak for themselves. Jumping forward four decades, Heritage Audio, working in collaboration with Ardent Studios, has created the Herchild Model 670 Ardent Edition. This limited-run stereo limiter/compressor will be available in very small quantities, so you would be wise to reserve yours at Sweetwater while you can!

The modifications

The Heritage Audio Herchild 670 Ardent Edition modifications give your workflow a tremendous productivity boost. The attack and release times have been tweaked to perfectly match Ardent’s modified vintage units. You have direct access to the continuously variable slope control (DC Threshold), which on the original 670 is adjusted via internal trim pots. This allows for adjustment over a wide range, from a seamless transition between compression and hard limiting to a harder, more pronounced knee. It’s rare to see a modern compressor without a sidechain filter, a critical tool that allows you to minimize the influence of low frequencies on compression action. While the original 670 didn’t have one, Heritage Audio’s 670 Ardent Edition now offers this indispensable usability feature with four selectable frequencies to precisely tailor compression action to the needs of your source material.

Smart, program-dependent soft-knee compression

The buttery-smooth sound of the vocals on Beatles’ records is largely thanks to the original Model 660, the mono version of the famous compressor, of which EMI Studios (Abbey Road) owned several. (If you prefer a mono unit, note that Heritage Audio also makes the Herchild Model 660 Ardent Edition.) This sound is the result of a number of factors, including a plethora of tubes and transformers. An inherent sonic attribute of this type of “variable-mu” dynamics control is the gentle, soft knee of the compression curve, with reasonably fast attack and fairly long release times. It’s also program dependent, so gain reduction starts at a very low ratio on small peaks and gradually increases to brickwall territory on very loud input signals.

Discover the power of mid-side processing

Like its vintage inspiration, the Heritage Audio 670 Ardent Edition works differently from most other compressors. The original design dated from the late 1950s and addressed the need for effective level control in vinyl disc mastering. The stereo long-playing record was becoming established and existed alongside monaural LPs. Being that stereo disc grooves stored twice the amount of information as those of a mono LP, dynamic shaping of the program material was essential (as was stereo/mono compatibility). The 670, placed in front of a cutting lathe, gave the mastering engineer precise control over the depth and the width of the grooves in order to maintain sufficient program length and level for an LP to be competitive with other commercial releases. Like the original, the 670 Ardent Edition features LAT VERT as well as LAT VERT LINK modes. If you’ve discovered the advantages of mixing and mastering with mid-side (M-S) processing, LAT VERT gives you mid-side functionality for mixes with increased width, depth, and focus. LAT VERT LINK does the same, but with the two channels linked.

Heritage Audio: legendary performance and epic value

Founded in 2011 by engineer/producer Peter Rodriguez, Heritage Audio immediately set about designing and manufacturing equipment inspired by legendary vintage British console modules. The company leverages the same handwired, transformer-coupled Class A circuitry with functionality aimed at today’s studio workflows. In 2021, the company turned its attention across the Atlantic with the acclaimed MotorCity EQ, followed by the Herchild 670 and 660 tube limiter/compressors, and now the 670 and 660 Ardent Editions. Designed to stringent tolerances and meticulously crafted in the company’s factory in Spain, Heritage Audio gear delivers clean, problem-free audio with generous headroom and the vintage-flavored sonics we all crave. Sweetwater is proud to offer you this distinguished line of high-performance pro audio equipment.