Let’s Discuss the D.A.V. Broadhurst Gardens No.3 (BG-3) Mastering Equalizer
To Judge a Book By Its Cover
The BG-3 may look unimpressive, but it is everything that claims to be, which is more than can be said for countless “mastering” grade equalizers.
Founded by Mick Hinton in 1997, D.A.V. Electronics has cemented themselves as a monolith in British audio. Sporting an acronym representing Digital Audio Visual, Hinton’s no-nonsense approach to product design and development is clear from the start. Since its inception, D.A.V. has designed and manufactured quite a few high performance microphone preamps and audio processors. The overwhelming majority of the company’s products are from their Broadhurst Gardens series, named for Hinton’s 29-year tenure as a technical operator for Decca Studios at Broadhurst Gardens in West Hampstead, London.
Decca Studios, a recording facility controlled by Decca Records, saw the beginnings and peaks of many artists’ careers, from art rock icons like David Bowie to big band jazz legends like Ted Heath. In fact, the Beatles actually failed their audition for Decca Records there in 1962, hence their subsequent signing to Parlophone. Throughout the 1960s, Decca Studios was an establishment with a reputation similar to facilities like Abbey Road Studios. In fact, the production standard set by Abbey Road Studios was the primary factor in erecting the Broadhurst Gardens studio; Decca Records had to produce commercially competitive audio.
One might wonder why such history is relevant to a discussion about a mastering equalizer. Put simply, the time that Hinton spent at Decca Studios is apparent in his products’ design and sonic footprint. For example, Hinton worked for Decca during the inception of stereo audio. Most of his coworkers at the time were ex-Royal Air Force Radio Operators. This was the beginning of audio production becoming an art form as opposed to the science as which it was then regarded. Hinton’s designs fall into a strange place in that regard -- they’re scientifically musical. Or are they musically scientific?
The Broadhurst Gardens No.3, or BG-3, is a low-distortion, electronically balanced parametric mastering equalizer. Physically, the unit is 2U high and fairly lightweight. On the faceplate, the unit sports 18 Grayhill rotary switches for frequency selection, band gain, and output gain. In addition, one will find switches for a high pass filter at -3dB at 28Hz with a slope of 18dB per octave. Frequency band gain is +/- 2.5dB in 0.5 dB steps while output gain is -5dB/+6dB in 1dB steps.
There are 4 LEDs on the faceplate indicating the engagement of the aforementioned high pass filters and the bypass state of the equalizer. On the rear panel, one will find well-labeled balanced connections and a standard IEC power socket.
On a mildly Interesting note, the Grayhill switches are the only components in Hinton’s entire product catalogue that are not made in the U.K.
Function Over Form
Hinton has stated that if he were to make his units look more attractive, the price would likely skyrocket.
Visually, the BG-3 is profoundly boring and industrial. It looks like a broadcast-specific unit that isn’t intended to be client-facing. This is no coincidence, as the metalwork for all the company’s products is done by Bryant Broadcast in the U.K. On the subject, Hinton has stated that if he were to make his units look more attractive, the price would likely skyrocket.
On to particulars, here. The unit features 2 shelving curves and 2 resonance (bell) curves. The bandwidths are fairly broad and, based on initial intuition, well-suited for mastering applications focused on general shaping.
The low shelves offered are 12.5, 25, 50, 100, 200, and 400Hz while the high shelves are 2, 4, 8, 12, 16, and 32kHz. Low resonances are marked at 30, 60, 120, 240, 500, and 750Hz while high resonances are marked at 3, 4, 5, 6, 8, and 10kHz.
One might assume that these selections are rather general and therefore poorly suited for surgical spectral tasks. That assumption would be correct. The frequencies were selected by mastering heavyweights that Mick worked with for decades and were likely chosen for general shaping only.
In use, the BG-3 sounds wonderfully transparent. One can add air, brightness, and body to program content without much of a sonic footprint. The high pass filter is minimally invasive in terms of phase shift while managing to do away with undesirable subharmonic energy. Specifically, the high shelves are incredible.
Here at Rose Quartz, I’ve found that implementing the unit’s 2kHz shelf can lift a track right out of our speakers. Whether it be a vocal that isn’t quite upfront enough, a snare that’s just under the surface, or guitars that need some edge, I’ve found that my first instinct (after subtractive equalization of colluding frequencies) is to use the “lift” that the BG-3 offers in the form of a 2kHz shelf. Typically, 1 to 1.5dB is all that is required.
In terms of presence and air, the BG-3’s 32kHz shelf is widely regarded as an excellent method to add or remove spectral energy in the upper register of program material. In that region, a 0.5dB boost or cut can go a long way, removing nasty high-end pileups or breathing life into a rather dull mix.
On the other end of the spectrum, the unit handles low-end fairly well with cuts. Cleaning up program material’s bass response is quick work with the high pass filter and low shelf. In use, I’ve found that a 12.5Hz or 25 Hz cut with the rotary switches “slammed” to their maximum range of -2.5dB is sufficient to tighten up tracks that sport excessive bass.
However, in regard to adding low-end with the BG-3, something is left to be desired. In my experience, this unit simply adds flabbiness when tasked with beefing up program content. Even when adding 0.5dB at 100Hz, some kind of woolyness or looseness is introduced. I can imagine situations where this could be useful, but for modern masters, I shy away from boosting low-end with the unit.
Perhaps my favorite aspect of the BG-3 is the low resonance band’s ability to purge a track of woolyness. Picture a vocalist singing with a hand over their mouth. A 1.5 to 2dB cut at 120 or 240Hz can take that hand away, pulling a lead vocal out of bass drivers to enhance clarity and emphasize speaker separation. It may not be the only tool used to accomplish this task, but combined with a surgical cut somewhere in the low mids, one can shape that wooly region without excessive difficulty.
In addition, one can shape midrange fairly well with the low resonance band using 500 or 750Hz boosts or cuts. I’ve worked on quite a few records that lacked midrange prominence. Initially skeptical of the unit’s ability to add midrange energy, I thought that a 1kHz boost was necessary to fill out my speakers’ midrange drivers. I could not understand why there wasn’t a 1kHz bell offered on the BG-3. However, in use, the 750Hz region proved to be a better area for the boost that I had in mind as it didn’t introduce harsh spectral pileup between 1 and 2kHz.
Finally, the high resonance band is great for shaping problem areas within a track. For example, harshness in guitars and vocals can be tamed with a cut at 3 or 4kHz, often with the rotary switches slammed to -2.5db. Harsh sibilance can be mitigated, to some extent, with a similar slammed cut at 8 or 10kHz. Of course, this task would be combined with the implementation of a high frequency limiter or de-esser.
The BG-3 has been a staple on 90% of records that come through Rose Quartz since we acquired it in early 2020. For some time, it was the only analog equalizer that I was using. Combined with an excellent mastering compressor like the Knif Vari Mu II, it worked wonderfully as an EQ to shape the overall characteristics of program content. In conclusion, the unit is sticking around. Oh, and as a closing note here, price typically wouldn’t be a factor in a review like this, but at under $2000 USD, this unit is likely the most affordable mastering equalizer around. It sounds like 4 to 5 times its sale price of $1620.
Davelectronics.com
$1620 USD
P.S. There aren’t too many mastering houses that use the BG-3 these days, that I’m aware of. However, one notable user is J. LaPointe at Archive Mastering. It’s one of 2 analog equalizers in his signal chain.