Seattle's DIY Wizards are at it again — this time with more preamps taking advantage of the 500-series format. The Elements line-up of preamps includes four models: Gold, Copper, Bronze, and Silver. Each "element" promises a distinct tone. Available in kit form, all of the preamps share a similar topology of a single op-amp coupled with input and output transformers. The op-amps use the standard 2520 format made popular by API, John Hardy, et al., and because they're socketed, it's easy to swap them and experiment with more sounds. If you are not comfortable building your own preamp, Hairball offers the Gold, Copper, and Bronze models fully assembled as a cost option. 

The kits come with everything you need to complete the build, including a PC board, fully shielded enclosure, phantom power, customizable pad, polarity switch, DI input (thank you!), and choice of variable or stepped input. You'll also receive an appropriately colored anodized aluminum faceplate. The Silver kit is unique, and I'll discuss that in its own section. But first, I want to cover the preamps in use. 

Gold is a clean preamp that we informally started calling the reference preamp. It is based on the 990 discrete op-amp detailed in Deane Jensen's JE-990 AES paper, which set a standard as a workhorse high-fidelity design. Transformers are custom built by Jensen (to accommodate the 500-series format height). On almost any source, the Gold is realistic and true. It goes toe-to- toe with our John Hardy M-1, providing tons of gain while maintaining a low noise floor. We liked it on voiceovers, vocals, and acoustic instruments. When used with a tube mic in omni mode, the Gold preamp seemed perfect for a horn trio session, with a clear top that avoided edgy overtones. In a rock context, the Gold's transparent design is not as sexy or aggressive as other Elements, but you can't go wrong with this choice. If you do a variety of styles, Gold (or the Hairball Audio Lola [Tape Op #93]) could be your best bet. One last note: All of our test models had the optional Grayhill stepped gain switches — critical on the Gold line. Voiceover, brass, and acoustic-guitar sessions have a way of being recalled, and being able to bring back precise gain settings was a blessing. Lest the Gold appear sterile or boring, we found a favorite use for it — guitar solos. For example, with a dynamic mic on a Danelectro practice amp, we cranked the Gold input gain to 9 and clamped the output trim low. The result was a blown-out mess that sat above the mix better than if we had dialed it up with plug-ins. 

Copper is the character preamp. We initially dismissed it as (yet) another 1073 clone, but inside, things are different. Rather than copying the classic Neve circuit, Hairball worked with the transformer manufacturers to approach the British console sound through a different topology. Drawing from Eisen Audio's years of servicing vintage Neve modules, Hairball dialed in perhaps the optimal capacitor configuration. It's that combination of caps, transformer, and op-amp that gets you far closer to a Neve than just copying a schematic. The custom I/O transformers come from Ed Anderson, a respected designer. The BA512 op-amp is from Eisen Audio and is inspired by the BA440 op-amp found in some vintage BBC consoles. Copper was the most popular of the Elements we tried. Using the input gain in conjunction with the output trim, this preamp can start out clean and gradually shift into saturation. For electric and bass guitars, Copper added sizzle and dimension to the sound. One tester, Dave Cerminara, said if he were starting a studio, he would grab eight Hairball Audio Copper preamps immediately. 

Bronze is a unique take on a preamp. Rather than copying a console input, Hairball looked to the well-known LA-3A compressor. Face it, a lot of people stack 1176 and LA-3A processors right after mic preamps to take advantage of the transformers, with the compression circuit often bypassed, but the signal still passing through the I/O sections. Why go through that trouble when you can just have the right preamp out of the gate? Bronze could be that preamp. Hairball consulted with Eisen Audio to adapt the LA-3A output amp for the 2520 format. The result was dubbed the Raindog op-amp. A Cinemag CM-2511 input transformer in combination with an Ed Anderson B11148 output transformer gives you a lot of color. 

While the other preamps land in well-known categories, Bronze is definitely its own beast. With thick lows and muted highs, this is a specific-sounding option. When used with drum room mics, Bronze tamed cymbals, providing a "Motown" vinyl sound. And the more Bronze is driven, the more pronounced the low-pass effect. If you like to saturate your kick, snare, or overheads with the transformers in your preamps (a technique commonly used with the 1176-like Universal Audio 2108 preamp [Tape Op #31]), then Bronze will take you in that direction. The DI comes in handy for thickening keyboards or other electronic instruments. For bass guitar, it can be a definite go-to choice for alternative rock. On electric guitar, Bronze was fine for power-chord rhythm work, but seemed "slow" for faster or more articulate noodling; the resulting sound was warm, but smeared in the low-mids. On the plus side, Bronze is unlike other things we've heard; it really responds to input-gain manipulation, perhaps more than the Copper does, with tons of vibe and saturation. The downside is that Bronze is not an all-around preamp that can be easily used on everything, like Gold can. For someone looking for something completely different, a darker preamp, or some unique transformers to abuse, Bronze stands alone in this regard. But if you're limited in your preamp arsenal, Bronze does not afford a great deal of flexibility. 

Silver is the tweaker's dream. Some of you may recall my review of the Eisen Audio DIY500 mkII [Tape Op #80], a PCB kit that required users to choose their own op amps, transformers, and components. Unfortunately, Eisen Audio discontinued that product after our review ran. Once stock was depleted, there was no longer an easy way to pursue that kind of project. However, Silver is a resurrection of Eisen's concept. For $99, you receive PC board, fasteners, aluminum faceplate, some basic components, and instructions for choosing the remainder of the components for your very own creation. Now I can make more of the "Treelady Labs TEL500" preamps we built for that review. Thank you Hairball. And I've already started emailing the readers who sent their displeasure my way when Eisen ran out of stock. Well, it's time to fire up that soldering rig and get busy. This should be fun. 

We really enjoyed the Hairball Audio Elements preamps. Each model brings a distinct tone to the market. Our only note is the physical colors of the Element faceplates make it difficult to tell the Copper and Bronze apart, especially in low-light studio situations. Not a deal killer, but you don't want to accidently grab one model when you wanted the other. If you are handy with a soldering iron, and have built a few projects, do not hesitate to pick up an Elements kit and start building. But don't blame me if you end up buying eight or more. I'm just the messenger. 

Tape Op is a bi-monthly magazine devoted to the art of record making.

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