Bespoke Audio Company TVC Preamplifier

Our debut product is a pre-amplifier, the heart of a high fidelity audio system. We have focussed our years of high end audio experience into research and development to produce the ultimate line controller.

We proudly present our highly acclaimed, multiple-award-winning pre-amplifier - cherished by music lovers around the world.

A flexible design with six inputs and two outputs in any combination of balanced and unbalanced connections.

An extensive palette of technical options and finishes ensures your pre-amplifier complements your system.

Choose one of our suggested configurations or let us work with you to create something which satisfies your every desire. The decision is yours.

Why a pre-amplifier? A pre-amplifier is the control centre for your whole system. It's the interface between yoursources (CD, Turntable, Tape, etc.) and your amplifiers.Put simply, your pre-amplifier lets you select which source you are listening to, and howloud it is.Everything is connected here, it's the heart of a high end audio system.

Why a passive pre-amplifier? To be clear, our opinion on the merits of a passive pre-amplifier over an active design isonly that: our opinion. It is also inherently biased, since we make a passive pre-amplifier!There are many music lovers who use an active pre-amplifier and enjoy exceptionalsound from their systems. There is no right and wrong in music reproduction, there areonly preferences.

Modern sources have output levels which are more than capable of driving amplifiers totheir maximum volume. So, a pre-amplifier is almost always used to reduce (or attenuate)the signal level. Since there is no need to increase gain, the active element of a pre-amplifier could be considered to be effectively redundant.

Unfortunately, even though they are redundant, the active electronics can cause problems:

• Active electronics introduce noise. This is often heard as a hiss when no music isplaying, but it's also there when music is playing.
• Active electronics rely on the quality of their power supply. This can be a problembecause good internal power supplies are expensive and difficult to make andbecause even the best power supply is reliant on the quality of the mains electricityfeeding it, which is often far from perfect!
• Active electronics can cause distortions. “Distortion” doesn't always mean the soundof a fuzzy electric guitar. In this instance the term “distortion” is simply defined aschanges between the signal going into the pre-amplifier and the signal going out.Unless an active circuit is exceptionally well designed it is likely there will be somedistortion, however small. In a good design, this distortion might be so small thatit's nearly inaudible, but it is always there. And of course, not all designs are good!

Of course, in some circumstances, for some listeners, an active pre-amplifier ispreferable. It might be that the active pre-amplifier adds something to the sound in apleasing way. It might be that the active pre-amplifier's sound, when balanced with aparticular sound elsewhere in the system results in a neutrality, or in a performance whichthe listener enjoy.
Our approach is that the loudspeakers should be suited to the room, the power amplifiershould be capable of driving the loudspeakers and the pre-amplifier should be astransparent as possible. Any particular sonic signature the listener prefers should ideallycome from the source or from the loudspeakers. The amplification chain should offerneutrality, otherwise there is potential for the system to operate as a kind of “see-saw”where each component's performance is dictated and affected by the others. Thisapproach can, of course, result in excellent performance, but it can prove a problemwhen one or other part of the chain is changed.

Why a transformer passive pre-amplifier? One option is to simply remove the active element of a pre-amplifier and just use thevolume control (either as a potentiometer or as a stepped resistive “ladder” attenuator) – called a resistive passive pre-amplifier.

This partially ameliorates the possible problems associated with active electronics (above),but there are some technical issues. Briefly, relying on only resistive attenuation can resultin very poor impedance matching. This can lead to problems with high frequencyresponse and may explain the common perception that passive pre-amplifiers lack“drive”. In order to minimise this effect, it is necessary to use short interconnects, and topay careful attention to the source and load impedances.

The results with resistive passives can be excellent, but the technical limitations can meanthat compromises must be made elsewhere in the system (cable length and thespecifications of other components), which might not be ideal.

Another solution is to use a transformer with a multi tapped secondary winding to allow itto step down the level in various increments – a Transformer Volume Control (TVC).

A good analogy here is with a car. Using a resistive passive is a little like putting thebrakes on, it's inefficient. Using a transformer is like changing gears – the engine isalways working at it's optimum pace, we're simply using gears to adjust it's pace to ourown preference.

There are many other benefits to using a transformer, not least of which is the ability toconvert balanced and unbalanced signals in either direction. There's also the ability tocompletely isolate/decouple the source and load (called Galvanic Isolation), to breakground loops and further minimise noise.

Why The Bespoke Audio Company? We've been involved in the design and manufacture of multiple award winning audioproducts for the last ten years. We are confident we have the experience, the know-howand the proven track record to supply and support high end audio products and theirproud owners.

Right from the start, we wiped the drawing board clean and worked to remove anyrestrictions. We worked with, and consulted with, other designers. We spent time with alocal electronics genius, who is also an enthusiastic audiophile and who has a unique perspective, informed by years of servicing and repairing vintage hi-fi. His input wasparticularly useful because he has very little experience in transformer design, so was ableto help us approach things from a perspective less prejudiced by habit, convention orengrained thinking.

In simple terms, a transformer is made by forming a wire coil around a core. The wireitself is wound onto a bobbin and the core is inserted into the bobbin (and therefore thecoil). In order that our transformer design would not be constrained by commerciallyavailable components, we designed our own bobbin. This means we have more space toexperiment with winding design and we can use a larger core, to great effect.

We experimented a great deal over many months with different approaches and designs.Transformer design follows basic rules of science, of course, but we wanted to see whatwould happen if rules were ignored. The luxury of time to experiment like this meant wecould try things that would not normally be given consideration. Breaking with conventionusually produced predictable test results, but the sonic performance wasn't always asexpected, and this meant the potential existed for progress and spurred us on to keepexperimenting.

Over time we narrowed things down to a few different design options and we built basicpre-amplifiers into identical (off the shelf) enclosures. We gave these pre-amplifierscommon English male names like Nigel and Roger to try and remove any preconceptions,then sent them out to various listeners whose opinions we value and asked them to trythese prototypes in their systems and let us know what they thought.

The response from the listeners was very positive. We found an instant, universal andcompelling opinion prevailed and we were reassured that after many months of learningand experimentation, we'd found what we were looking for: a design which we feelpushes sonic performance beyond what could have been expected before.

Unfortunately, the transformer had become too large to fit into readily available shieldingcans so we had to have a tool made to manufacture our own Mu-Metal cans. Our helpfullocal electronics engineer explained that in his experience of repairing older equipmenthe'd found the petroleum wax used to pot transformers was corroding the lacquer onwinding wire. Eventually, over an extended period, this caused transformers to failcompletely, but he also speculated that before this total failure, there must also be a pointwhere the transformer's performance will be impacted. For this reason, we chose to potour transformers in beeswax.

We've taken the same care and applied the same meticulous attention to every aspect ofour pre-amplifier, from the exquisite casework to the individually printed owner's manual.Finally, we strive for complete excellence in the supply and support of our product, fromthe first enquiry to the delivery of the hand made unit itself and beyond. Our productscarry a lifetime guarantee, so it's not unreasonable to say the service lasts forever.