using tubes is no small challenge. To achieve the design goals we had to address two
fundamental issues: (1) Deal with the sonic bottlenecks that occur in the multiple stages and
functions of known preamplifier designs, and (2) design a preamplifier that will work in as wide
a variety of conditions as possible, as unaffected by outside environmental influences as
possible. The sonic performance should be musical, predictable and consistent, regardless of
AC condition, load, source component, physical vibrations or digital or other external radiated
noise.
During the long four-plus years of the R&D development cycle of this project, the 5-man VTL
engineering team was given the mission to create the best single-chassis preamplifier that we
could possibly make. During this time our panel of listeners was given the mandate to be
relentless in pushing the requirements for the design envelope -- parts were changed and
modules re-designed over and over again until we were satisfied with all aspects of the sonic
and measured performance.
Making a preamplifier that is capable of driving any load with any length of cable without
flinching is an extremely challenging prospect. In designing a completely novel push-pull low
impedance output stage, and taking a radical approach to the volume potentiometer by
incorporating relays and discrete resistors in an innovative combination, we have finally been
able to significantly improve upon the highly-regarded TL5.5 sound. By coupling this
technology to multiple super-regulated power supplies we have dramatically improved on the
preamplifier’s capability to drive any power amplifier, with truly superior resolution, spatial
imaging and bass control.
Finally, the VTL TL 6.5 Preamplifier is designed primarily for the user whose primary source is
a line source. If phono is a primary source then a separate phono stage will be required to step
the cartridge voltage up to line level and to handle the RIAA equalization needed to re-equalize
the signal from the record. Since this stage is usually a high gain stage and is therefore
susceptible to noise, it is sonically better to separate this stage from the line preamplifier.
The VTL team is proud that you have selected our Signature preamplifier as a new member of
your home audio system. This preamplifier is designed to give you the convenience and
flexibility to manage all your audio and video sources, while at the same time giving you the
musical experience that is the most alive and the truest to your source, and we certainly wish
you many hours of enjoyment from it.
Symbol Conventions used in this guide
Certain symbols are used in this owner’s manual to draw your attention to important
points being discussed. For your own safety and that of your equipment you should
note and heed the warnings that follow these symbols.
The “Warning - Pay particular Attention” symbol used is
And the “Warning – Observe These Precautions for Your Safety” is
TL6.5 Preamplifier Owner’s Manual
VTL
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