Inside Ovation's Acoustic Pickup Evolution
The piezo pickup designed by Ovation engineer James Rickard was awarded a U.S. Patent in 1973 and is still used in the majority of the company’s guitars today.
In my last column, A Piezo Pioneer, we talked about Takamine, one of the pioneers in the amplification of acoustic guitars. The other major brand offering factory installed, full systems (pickup and integrated preamp) in the ’70s was Ovation. Designed by an Ovation engineer named James Rickard, their innovative pickup was issued U.S. Patent No. 3,712,951 in 1973.
The Ovation design differed from Takamine’s in that it sat in a saddle slot in the bridge, rather than in a structure that coupled to the saddle from underneath the bridge. Like the Takamine pickup, however, Ovation’s pickup used six very massive, piezo-ceramic elements. Consequently, the pickup and its integrated 1/4" saddle was much wider than the more traditional 3/32"-wide saddles that were commonly used by companies like Martin, Gibson, and Guild.
To understand what makes this baby tick, let’s talk about what’s under the hood. Starting at the top (Fig. 3), we find a molded plastic saddle that is segmented like a toy snake. This design feature allows the saddle to be a one-piece affair made out of a fairly hard plastic. Yet it still maintains the flexibility needed to direct the force of each individual string directly downward onto its respective piezo element. This segmentation also eliminates undesirable crosstalk and phase cancellation from the adjacent strings.
The saddle is shaped like a tent (Fig. 6) and contacts the piezo element only on the edges of each element. The resulting pocket over the top face of the elements provides the necessary space to solder a buss wire (in this case the ground buss) directly to the top face of each sensor.
On the bottom of the assembly, the elements ride on two plastic rails running along their edges. This creates another pocket that provides clearance for the bottom solder connections of the positive signal buss. The entire assembly is then inserted in a grounded, aluminum channel that acts as both a supporting structure and a Faraday cage that shields the positive buss and electrodes from electromagnetic interference.
During assembly, the structure is injected with an RTV silicone-rubber compound, which fills the air gaps, seals the ceramic elements, and holds the structure together. Since the pickup and saddle form a unitized assembly, thin plastic shims were inserted under the pickup during set up to allow for action-height adjustment.
Ovation’s pickup design is still used in the majority of their current offerings, but their preamps have advanced significantly, now providing multi-band tone controls and onboard tuners.
Overall, the Ovation system, like the Takamine, is a great, no hassle, plug-and-play solution offering excellent performance in high-volume stage settings. From my experience designing pickups, however, I do see two major problems with the Ovation system. The first is its massive size, which is primarily an aesthetic issue since it just looks out of character with a traditional acoustic guitar. The other problem is that all the interceding materials incorporated in the design (aluminum channel, plastic rails, silicone rubber, etc.) tend to decouple the pickups response from the body tones and lean a little too heavily toward the string tones.
Let’s fast-forward to the ’80s when it was routine to see acoustic-electric Takamines and Ovations sharing the stage with electric guitars, basses, and drums in many of the leading country-rock and “hair” bands. Meanwhile, if you owned a Martin, Guild, Gibson, Taylor, or Fender acoustic, you were relegated to standing statue-still behind a stage mic, struggling to be heard. While this setup was fine for an acoustic-bluegrass band or for a soloist in a coffee house, it just didn’t cut it playing alongside electric instruments and drums in larger venues. Consequently, these companies were losing sales to the ready-to-go acoustic-electrics and were beginning to understand that they really needed to jump on the bandwagon.
Seeing this opportunity, California-based transducer company Barcus Berry developed a large format, 1/4"-wide undersaddle pickup that was showing up in some Guild models, and Japanese supplier Nanyo Boeki was supplying a similar system to Ibanez, Hondo, and Aria. L.R. Baggs released a smaller take on the Ovation pickup with their 1/8"-wide LB6, which had a metal body that supported the ceramic elements and an integrated saddle that bonded to the chassis. The LB6’s saddle material was not segmented like the Ovation, and had to be handcut to create the necessary radius and saddle height before installation. This was always a good-sounding pickup and enjoyed a loyal following, but the handfitting required for installation prevented it from being adopted by manufacturers who needed a more production-friendly solution.
Still looking for a non-invasive solution that would not require the alteration of the basic guitar structure, Martin approached Barcus Berry and requested a scaled-down variation of their wide-format, undersaddle transducer. This new design fit into a conventional 3/32" saddle slot and was brought to market by Martin as the Martin Thinline 332 in 1983. The pickup was first introduced in the Martin Shenandoah series and was also sold as an aftermarket retrofit.
Although the Thinline 332 had promising initial success, some fundamental design flaws and quality issues prevented it from reaching its full potential. It was because of this initial success, however, that Martin reached out to other designers in an attempt to remedy some of the issues and reintroduce the product.
Next time around, we’ll take a detailed look at the result of their outreach!
Larry Fishman holds more than 30 patents in transducer and musical instrument design. He is president and founder of Fishman Transducers, which he began in his garage in 1981. In the early ’90s, he also co-founded and managed Parker Guitars (which was later sold to U.S. Music Corp.) with his friend Ken Parker.