Sound System at Bohemien

Updated: Jun 29

The sound system at Bohemien is divided into three parts, one of which consists of the Altec Model 17s, the line arrays another, and those that run on a 70V system, the pendants, the third.

Line array at Bohemien.

Tarek Debira, who owns Bohemien, also owns another restaurant, Chez Moi, and bar, Le Boudoir down the block. The original plan was to put up some cool old gear - cooler and better-sounding than the usual pro-audio black speakers in every other bar - and call it a day... but then had some other ideas.


I connected Tarek to my friend Perry Brandston, who has a long and storied history in the world of NYC nightlife sound, and continues that today with his work as part of Sound Concern and his latest project, Oda. Perry had installed a pair of similar arrays at Planeta that I had heard, and thought that they would be incredible in a space like Bohemien. Tarek was interested in a system that would be more experiential and part of the design of the space, so we all talked. After a few discussions, Perry sketched out the types and placement of speakers and what was required for the arrays, and then I took it from there to finalize the design, then fabricate and install.


While the Bohemien space had long been a bar, it’s not really designed for loud music - so the idea was to design a system that sounded great throughout the space, wasn’t bass-shy, but also one that wouldn’t shake the rafters or excite the room (or neighbors) too much.

Altec Model 17s at Bohemien

The Altec Model 17s in the rear, with vintage 604-8G drivers, always sound great - there are reasons that those nearly 50 year-old drivers still command top dollar. At Bohemien, they run full-range with minimal EQ, with a midrange to die for - way back in the day, these were the studio monitors. There’s no replacement for displacement, and if I get the chance to be in there by myself, sometimes I’ll turn off the rest of the system and just listen to those. The nature of the drivers is such that while they go down to about 30Hz, we still rely on the arrays for the rest of the low-end oomph in the space. Securely fastened to the ceiling, each weighs about 140lbs.


One of the line arrays at Bohemien, pendants visible to the left.

The arrays in the front of the space look striking, and add a lot to the sound and the experience - they’re about 9 ½’ tall, and comprise 136 drivers each - 8 12” woofers, 32 3” mids, and 96 1” tweeters. Each is a sealed box with two chambers inside - one for the woofers, and one for the mids and tweets. While the internal volume seems small-ish, because it’s an array and the excursion is minimal, it all works (and can be tweaked with EQ). The brilliance of the system lies in Perry’s design and driver selection - succeeding in both performance and price-point. It’s fascinating how with arrays in general - and especially with the piezo tweeters - individual driver irregularities disappear giving an improved overall response.

Mock-up of the sides of the enclosures.

The actual enclosures are rectangular, the radiused sides are a decorative element we added. (Or rather, I mean, are designed to help with edge diffraction! -ed.). They’re made from ½” Baltic birch kerfed on the table saw so as to bend it. The Dibond panel for the tweeters and front Baltic birch panel I had CNC’d by my friends at The New Motor (who also cut the pendants). A big part of this project was the added element of craftsmanship and fine woodworking - none of this is off-the-shelf - and in that area I think we succeeded.

Enclosures in process on-site.

Arrays behave as a line source, so you have a “column of sound” coming toward you, rather than a point source (like a “flashlight”) as you do with traditional speakers with individual drivers. Generally the sound "travels farther" with an array (like those J-shaped arrays you see hanging from the ceiling at venues) - although less of an issue in this case. Here, in a near-field setup, it's more a feeling that you’re wrapped in a cocoon of music, and you notice it each time you walk in the door. Because they’re facing one another, it’s not like a home setup, and that does create some irregularities with standing waves, but it’s not distracting.


What I like is the sense of “sound everywhere” - next time you’re there, stand next to one array, and you’ll notice you can still hear the other. No individual driver is terribly loud, so you can stand a foot away at peak volume levels, and it’s fine, and you get that effect standing anywhere between them. The arrays are tri-amped, with a dbx PA2 serving as the crossover. The woofers and mids are wired in series/parallel to achieve a reasonable load for the amplifier. The piezoelectric tweeters are also wired in series/parallel, but with additional resistors wired in series with the tweeters due to the nature of the piezos - to an amplifier, they look like capacitors.



The "pendants" - in process.

The pendants are designed to provide a bit of fill, clarity, and augment the sound of the Altecs and arrays - especially when it’s crowded. Each 8” driver sits in a doughnut of Baltic birch suspended from the ceiling. As an “open-baffle” setup (i.e. the driver is not in a box - both front and rear are radiating sound into the space), the size of the baffle (in this case, the width of that wood circle and driver) affects how low it will go. At lower frequencies, the wavelengths get longer, and eventually the out-of-phase waves emanating from the rear meet the waves from the front, and gradually cancel each other out - so no bass. With these, doing the math, that starts somewhere around 500Hz, which is right around the middle of a standard piano keyboard. With a bit of EQ, we can get it to sound ok for another octave lower or so, down to around 250Hz, but then it falls off, and no amount of EQ can fix that. Fortunately, this is just what we wanted - to hear the vocals, a bit of treble, but not sound boomy or wake the neighbors. If we listen to the pendants alone, they don’t sound great - like a speaker with a blown woofer - but together it all works.


The pendants run on a 70V system, and that’s the reason for the small transformers and wires you see on each of the speakers. Systems like these are most common in situations where you need a lot of speakers with long cable runs - larger bars or restaurants, department stores, etc. The higher voltage from the amp is stepped down by a transformer and is roughly analogous to the high voltage lines you see carrying electricity vast distances - it’s a more efficient system over longer distances. With this setup, the actual impedance of the speaker doesn’t really matter - all speakers are connected in parallel, and it’s easy to wire in one more wherever.


This isn’t really a setup for true fidelity - but it’s not supposed to be. It just makes the full bar sound surprisingly good - and more simply and elegantly than a bunch of black boxes with a lot of EQ. In addition, the transformer on each speaker has a number of different taps - e.g. 10W or 5W - which can be used to adjust the relative volume of each pendant individually. In our case, due to the spacing, it made sense to lower some and raise others to give a relatively even volume level across the space.


Currently, there’s a pair of Technics SL-1200 MkIIs in the bar connected to a small mixer, and that feeds into a Symetrix Jupiter system downstairs. An 8-channel QSC amplifer powers the Altecs and arrays, with a separate Ashly amp for the 70V system. A dbx PA2 sits between the 2-channel array output from the Symetrix and six array inputs on the amp. The Symetrix allows us to EQ all three systems and adjust the relative levels of each, add delay, and set presets.


The collection of a few hundred records is curated by Shawn Schwartz - of Halcyon and the former Output.


Like many things, it’s a bit of a work in progress - or that’s how I see it. While it sounds great now, there are always cool things Bohemien may want to try in the future - like running the Altecs off low-power tubes which could be incredible as those 604 drivers are just so efficient. Or we can also reevaluate some EQ choices, or upgrade the turntables, mixers, and more. Looking forward to see what develops.


Bohemien Bar is located at 97 Atlantic Avenue, near Hicks Street, in Brooklyn. In addition to the sound, they serve some serious cocktails and small plates too.



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