Technical Highlights
The following reasons are why VTL products are technically far superior to other tube products.
- Proprietary Auto Bias and Fault Sensing technology
- Fully balanced differential circuit in Signature and Reference amplifiers
- Precision Regulated Power Supplies
- Audiophile quality parts
- Hand crafted with care
- Listening as the ultimate test
Auto Bias and Fault Sensing
VTL’s proprietary logic-controlled automatic bias system is designed to keep the tubes at peak performance and operates completely outside of the signal path. The tube biasing circuit checks and adjusts the tube bias values automatically during the power on sequence, as well as when the amplifier is at idle (i.e. when no music signal is being amplified,) and drops out of the circuit path when music signal is detected.
Comprehensive fault sensing system in the amplifier monitors internal and external conditions, protects the circuits, and alerts the user under any adverse conditions. In the case of any malfunction of the output tube the amplifier is shut down to protect the circuitry and faults are indicated on the front panel, along with the blinking LED on the top deck next to the tube that caused the fault shutdown, to make diagnosis and tube replacement easy.
Fully Balanced Differential Circuit
The current generation of VTL’s Signature and Reference amplifiers feature a new fully balanced differential circuit all the way through. The amplifier will develop a balanced output signal from a single-ended input signal, and this fully balanced differential operation yield a much better rejection of power supply noise.
Precision Regulated Power Supply
The most important components of a tube amplifier are the output devices, power supply and output transformer. Any amplifier is only as good as its power supply, and we use a large capacity reservoir and big well regulated transformers, along with high speed solid state rectifier power supply for top end crispness and dynamic bass slam.
Moreover, our Signature and Reference amplifiers are further enhanced with our proprietary Precision Regulated Power Supply where all critical voltages are precision regulated for consistent and predictable performance under a wide variety of conditions. Huge energy storage reservoirs mean that the amplifier is capable of delivering huge peak current swings into demanding loads for powerful, musical performance.
Audiophile Quality Parts
VTL amplifiers differ from others in our approach to spending most attention (and cost budget) on the components that contribute to sonic performance. Each component used in our products is chosen for reliability and durability.
Custom hand-crafted with care
All VTL products are built in our Chino, California factory by an experienced team of technicians. Our team takes an immense pride in the high quality work they deliver, whether from the smallest amplifier, the IT-85 to our Siegfried Reference Monoblock.
Listening as the Ultimate Test
The design of all of our products goes from paper to prototype, with lab testing and then listening tests conducted in our factory listening room, in our home Reference system and our dealer’s showroom. The feedback gathered from these listening sessions determines the improvements needed to be made before the next iteration of the design cycle.
Listening tests are the ultimate determining factor in determining whether our product is ready for the market or not. Once our listening tests satisfy us that the sound is accurate compared to our live music references, the product goes into final design and production.
Other features
- Proprietary VTL Signature Output Transformer used in all Signature and Reference products.
- Stiff, well regulated power supplies, with separate B+ power supplies for each stage.
- Well regulated, low noise double- insulated power transformers.
- High capacitance energy storage.
- All solid state rectification for long life and high reliability.
- Specially matched, comprehensively tested and burned in tubes.
- Small signal frequency response: 7Hz – 100kHz, +0, -1 dB
- Full power frequency response: 20Hz – 25kHz @< 1.5% THD at rated power