Yup, friend…I reckon she’s the biggest fiddle anywhere in these here parts. 

Actually, this is a T-Rex 4-String Octave Viola in the process of construction. The varnish has just finished curing enough on this one that we could string it up for some evaluation. The components are nowhere near the caliber we will use on the finished instrument and the bridge has yet to be trimmed down to a reasonable height.

As big as it looks next to a regular violin, it has a 16” body (note: viola sizes are designated by their body length, expressed in inches). Because it is based on a Tertis viola pattern, it is really wide. The span of the lower bout is more than 10 inches. Nevertheless, some test playing confirmed that the instrument is surprising easy to manage and hold (yes, with an extra large shoulder rest), as the rib height is a manageable 38mm; about the same as a regular 16” viola.

Here are some more photos of the freshly varnished instrument, ready for the next stages of completion.

Available as a 5-String as well: While the instrument featured here is a 4-string, it is also available in a 5-string configuration.

The T-Rex Octave Viola and other amazing low-pitched bowed instruments are available at the Don Rickert Musician Shop.

Some More Details About This Instrument

For our initial testing, we used regular viola strings rather than octave viola strings. Even strung and tuned as a regular viola, the instrument really roars with sonic power!

This particular T-Rex Octave Viola (aka “chin cello”) will have even more power, as it is to be customized as an acoustic-electric.

It will have a custom large viola version of the best violin pickup available, a Twin Hybrid Model by Barbera Transducer Systems. This pickup has 8 dual piezo element transducers; that is 2 transducers (4 piezo elements) per string! That is a total of 16 piezo elements (most violin pickup bridges have one transducer, period). The idea of all of those transducers, which are located near the pinnacle of the bridge, is not necessarily to generate higher volume (although higher volume without feedback is possible with these pickups).

The purpose, rather, is to capture the true tones generated by the strings and that humans hear instead of the chaos of noise resulting whenever a transducer is placed on the soundboard, such as under the bridge. It is only through the magic of the human auditory system that a person’s brain can interpret what emanates from a violin’s body (especially the top) as music. The field that studies this and similar phenomena is called "Psychoacoustics".

A Bit About Installing the Barbera Pickup

A Barbera bridge has more mass than a regular bridge. Consequently, there is going be some muting…no way around that. The customer presented the idea of installing the pickup bridge so that it can be easily swapped with a regular bridge. This was a great idea. What follows is an illustration and brief explanation of how we will do this.

Note: The following does not explain that a bridge jack is to be used to raise the strings without the necessity for de-tensioning in order to swap the bridges.

Two Bridges

As previously mentioned, two bridges are involved:

1. A conventional large viola bridge
2. A custom Barbera bridge made to large viola size

First, the correct string height and fingerboard relief for octave viola strings will be achieved. This is all in the realm of conventional (except for the super fat octave viola strings part). Generally, more material is removed by planing the part of the fingerboard underlying the octave C string. This is to allow for a more natural bridge arch without making the string heights ridiculously high. You will see this asymmetrical fingerboard profiling process in use on most cellos and older violas that were strung with real gut strings (which have larger vibration arcs than synthetic or metal core strings). It is called a “Hill bevel.”

Once the conventional bridge and fingerboard profile is perfected, the Barbera bridge is carved to achieve the same height and as close to the arc as possible. It is important to note that Barbera bridges can only be trimmed at the feet, as the transducers are just below the surface at the top edge of the bridge.

Custom fabricated (by D. Rickert) ebony tailpiece with a built in gain control

A gain control is essential for a powerful pickup such as a Barbera. A gain control is kind of a hybrid between a volume and a tone control. Less gain produces a darker timbre. Higher gain, more mid-range and treble. Barberra does not make a gain control tailpiece for viola. A violin tailpiece would be far too short for a 16” viola body.

The tailpiece gain control will have an input jack, allowing for removal of the Barberra pickup bridge and substitution of non-pickup bridge. 

The tailpiece gain control will also have an output jack for running a small wire from the tailpiece to the main output jack, to be mounted on the left (bass) side of the instrument.

The details follow.

A: Dov Schmidt “Hollow” Harp Tailpiece

This is a viola size version of the renowned Dove Harp Tailpiece. It is hollowed out on the underside for purported acoustic enhancement. For our purposes, the hollowed out underside is to make room for the electrical components.

Our experience has been that these hollow tailpieces tend to break, especially when used for octave strings. We will be weakening the bridge even more by drilling a hole right in its middle for the gain potentiometer. For this reason, the entire underside of the tailpiece will be reinforced with carbon fiber or Kevlar fabric saturated with industrial epoxy resin.

B: Gain Control Output Plug-in Point

This consists of a miniature jack and plug, to which the output wire is connected.

C: Pickup to Gain Control Plug-in Point

This consists of a miniature jack and plug, to which the pickup output wire is connected. 

D: Pickup

Barbera Transducer Systems (BTS) Twin Hybrid 4-String pickup bridge for VIOLA; single “ganged” output

E: Custom-Fabricated Output Jack Assembly

This part will be designed a custom-made by D. Rickert. The main cable (to an effects array, DI box and ultimately to an amplifier) plugs in from the bottom.

F: Gain Control to Output Jack Plug-in Point

This consists of a miniature jack (part of the Output Jack Assembly) and a miniature plug connected to the Gain Control Output wire)

G: Custom 1 meg-ohm (1000 ohms) Gain Control Assembly

This is a special high impedance gain control made by NS Design and is compatible with the high output of a BTS pickup. A variety of knobs are under consideration. This is purely an aesthetic concern

H: Hill Bevel on Fingerboard

Part of the fingerboard under the C string is planed to afford the extreme vibration of the C string while keeping a reasonable arch on the bridge. This is especially important, as the arch of a BTS pickup bridge is unchangeable.

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Octave Violins and Octave Violas at Don Rickert Musician Shop