Little Castle Studio  'Holy Grail'  Acoustic Instrument Amplifier
Technical Description:
Getting good stage sound for acoustic instruments has long been the 'holy grail' of sound reinforcement work.  We believe  The Holy Grail acoustic instrument amplifier is the first real  comprehensive solution. Typical approaches have used either transducers that have terrible dynamic envelope characteristics, and despite their claims, inaccurate frequency response,  and/or microphones mounted inside the instrument.  Mics inside the instrument offer a truer soundscape of the instrument's character, but really are hearing an environment still quite different than what we hear outside the instrument.  People avoid exterior mics because of the obvious feedback problems, when trying to get enough stage level.

What we are offering is a way to use crown's cm311 headworn mic (or any other mic of choice) mounted outside the instrument, hearing the most accurate soundscape.  We have designed a very narrow and transparent four band tunable analog notch filter to seek and destroy feedback.  Used with the on-board hard limiter, it is extremely easy to locate and zap feedback.  This enables a gain in stage level of 6 to 9 db, which now makes for a more than useful stage level.  Our analog filter also has much better transient response and accuracy than the automatic feedback elimination devices on the market that go through A/D/A conversion to achieve their goal in the digital domain.

The system shown in the enclosed photo (being custom built for one of our clients) starts with two mic pre-amps, each with defeatable 3-band EQ , phase reverse,  phantom power with indication, overload LED, EQ in/out with indication, gain adjust, and spare balanced direct outs for each pre, for dry sends  The EQ can be custom tuned to your specifications.  Both mic pre's can accept any balanced or unbalanced input source available on the market today, anything from a transducer to an expensive studio mic.  This allows mixing and matching of sources.

The signal from both mic pre-s is then normaled and summed into the input of the analog notch filter, again with global defeat.  This filter has four sections, all capable of sweeping from 55hz to 14khz.  Each section has an enable switch, a hi/lo frequency range switch, a switch to widen the notch slightly, and coarse and fine frequency sweep pots.  Rear panel input jacks break the normaling, to enable inserting outboard processing.

Another critical part of the system is a simple switchable hard limiter, with indication, which allows turning system gain up to create feedback that is held at a safe, stable level while searching for it. Without it, feedback can either run amuck and harm performer's or audience member's ears,  or dissappear elusively and give you erroneuous clues about whether or not you found it!

Together, the notch filter and limiter make for a powerful tool to zap feedback in a way that is as easy to use as the tuning  dial on your fm radio to find a station.

The notch filter is followed by a master section with an equally powerful set of features.  Included is an onboard, true stereo, 18 bit multi-effects unit with 16 presets and a level control.  There is an additional separate effects send and stereo effects return with it's own level control. There is built-in hush noise reduction for the quietest operation imaginable. And last but not least, there are two sets of balanced direct outs, each with their own level control - one for outputting to the powered stereo stage moniter section, and one for outputing to the house system.

Once you finally dial in that gorgeous, studio-accurate sound you've been hoping for, you can output it to the front yourself the way you want it heard. No more sound-guy making bad decisions about what you should sound like!

The system is finished with a set of stereo powered speakers, built with audiophile grade Morel woofers and tweeters, as a final compliment to the level of accuracy achieved by the rest of the system.  Though the photos enclosed show a typical guitar amp configuration, the system is also available in an amp-head with satellite speakers configuration, to widen the on-stage stereo image.   Cabinets are hand-rubbed baltic birch.

This is a powerful system that works as beautifully on violin, sax, mandoline, flute, banjo(or any acoustic instrument) as it does on guitar.

It is also available in a variety of simpler forms, at a lower cost, the simplest being a single mic pre with notch filter and limiter only.   We nearly always build these units custom-configured to match your personal fantasy about what would really be perfect for you, based on your playing style, your existing setup, and your budget.

Pricing available upon request.

Here's what an expert luthier feels
about our systems:

Tuesday, April 20, 1999

To all acoustic guitarists and all acoustic musicians


As a guitar maker it is important to me that my guitars, when played on stage, have a natural and pure sound, a sound I have worked hard to achieve.

The  most natural and true to life sound reinforcement systems I have heard are those engineered and built by Horace Williams of Little Castle Studios in Vermont.  His systems produce unmatched gain and clarity starting from his music friendly feedback control (to name only one of the things he has designed) down to his audiophile quality speaker systems.

I recommend his miking and amplification systems to all my customers.  I use them myself.  Anyone interested in having the natural beauty of their instrument heard on stage should try this system.  There is no more natural sound.

Craig Anderson

1(802) 349-1280
Skype:   horacewilliamsjr
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