Posts Tagged ‘bias’

Does Plate Dissipation Affect Valve / Tube Life In Practice ??

Thursday, November 8th, 2012

In general, the obvious connection between higher anode dissipation and shorter tube life holds good, however,  many other factors affect tube life, including accuracy of heater voltages and the efficiency of tube cooling within amplifiers.

The tube leaves the factory with a known amount of cathode coating material which is the source of all the electron emission. In use, this material is used up as it emits electrons when heated by the filament and plate current is drawn.

If plate current is drawn before the cathode is at operating temperature, the surface of the cathode can be damaged (so called ‘cathode stripping’).

This is why the Standby switch should be off when the amplifier is warming up. If, however, the tube is operated for long periods with the filament hot with little or no plate current being drawn, then an oxide-like coating can form on the cathode, effectively blocking the emission of electrons even when normal operation is required (known as ‘cathode poisoning’). TubeSync takes care of this by automatically controlling the bias at both start-up and run conditions.

vacuum tube EL34 valve

Plate dissipation is generally quoted by the manufacturer as a maximum value which, if exceeded could cause damage to the tube and should not generally be used for ‘normal’ operation. The relationship between tube life and plate dissipation follows an exponential curve. Tubes operated correctly at around 30% maximum dissipation can have lives in the region of tens of thousands of hours and can last several decades of years. This figure decreases rapidly as the dissipation increases, in some cased down to hundreds or even tens of hours as they approach or exceed their maximum plate dissipation rating.

Cooling is extremely important as running tubes very hot also increases the risk of arcing and a condition known as thermal runaway, which can instantly destroy the cathode material, making the tube useless. Conventionally biased tubes are most at risk when biased towards ‘Class-A’ operation, as they experience maximum power dissipation when no audio signal is present.

TubeSync_225

Tube Amp Testing For Professional Stage Performers – Engineering Tube Talk

Tuesday, February 22nd, 2011

A common requirement for tube amplifiers used for professional and stage purposes is that there should be a high percentage of confidence that one or more tubes will not fail during the performance. Tubes are often thought of in the same manner as light bulbs, in that they are most likely to fail catastrophically at switch on. This means that the moments just after the switch on point constitute the most stressful and potentially damaging periods in the life of the equipment.

In an attempt to guard against this possibility, it is common practice to do one of two things on a regular basis.

1/ regularly remove the tubes and have them commercially tested;

2/ replace the tubes with new stock on a regular basis.

These two methods may give the operator a degree of confidence but in fact, it can be shown that the faith placed in both methods is misplaced.

It is a known fact that removal of a tube from its socket results in a number of potentially damaging mechanical stresses on the metal to glass seals around the pins. Each insertion of an all glass tube will cause micro-cracking of the glass around the pin. This will invariably cause a small leakage of air into the valve, causing ‘gassing’ and eventually leading to its demise.

Removal for testing will also break the intimate contact between the holder and the tube contact pin, resulting in a poorer contact on re-insertion.

Many tube testers apply unreasonable electrical stresses to the tube internal electrodes and it is not uncommon for a known good valve to be damaged during the test. Tube testers can also give erroneous results depending on the way they perform the tests, possibly allowing faulty tubes to show ‘good’ and the good valves to be rejected as ‘bad’.

The second method of ‘blanket replacement’ with new stock on a regular basis can also lead to problems because if the failure distribution curve for tubes is analysed, it can be seen to follow the classic ‘bathtub’ failure curve. This inevitably means that an amplifier which is regularly ‘re-tubes’ will inevitably be considerably more likely to fail during the first hundred hours service than one which has been left untouched.

TubeSync overcomes these problems by performing an ‘in circuit’ test on the tubes every time the amplifier is powered up. The mutual conductance (gm) of the tube is measured by monitoring the cathode current of each valve whilst adjusting the grid bias in fixed steps. The results are tabulated and the new value is compared with previously stored values. A decision is then made on how far the tube has decayed in emission since the last test. Outputs from the device inform the user of the predicted remaining life of the tube.

TubeSync_350

TubeSync Service Points : Why Should You?

Friday, September 10th, 2010

TubeSync technology

TubeSync streamlines with the amp’s circuitry to constantly test and monitor the amp without altering the fundamental amplification process, tone or sound. It eliminates the need for bias current matching, increases tube life by micro-adjusting the bias on each tube, predicts tube failure and can, in the event of tube failure, even run the amp at half power, preventing catastrophic amp damage. ­­

The result is an amp unhampered by many of the problems associated with conventional tube amplification allowing musicians to enjoy classic tube sound quality without the frustrations.

These are just some of TubeSync’s unique features:

  • Eliminates the need for bias current matching of output tubes
  • Micro-adjusts the bias on each tube to ensure its full potential is realised
  • Assures reliability
  • Maintains optimum performance
  • Increases tube life
  • Reduces quiescent power consumption
  • Sets tubes at their optimum temperature as soon as you power up
  • Detects tube failure and prevents catastrophic damage to amp
  • Switches out faulty tubes and runs amps at half power until tube can be changed

A new industry standard

TubeSync technology has now been incorporated in new amp designs from some of the world’s most prominent amp manufacturers. Hiwatt, famed for their legendary reliability, was one of the first OEMs to recognise the potential of TubeSync for further enhancing the reliability and performance of their amps. KBO Dynamics continues to work with the industry’s biggest names to raise the bar in tube performance and reliability, creating a new industry standard in amp design and manufacture.

Introducing the Bias Engine

The Bias Engine is the hardware that encapsulates TubeSync’s unique technology. Fitting the Bias Engine is a straightforward procedure, with all necessary components supplied within the retrofit kit. It is stipulated that the Bias Engine is fitted by an accredited technician.

Bias engine retailThe Bias Engine is sold as a part of the TubeSync Professional Amp Upgrade Kit containing:

TubeSync Bias Engine Hardware

TubeSync hardware is wired straight into the amp’s circuitry. The Bias Engine is a very compact component that can be incorporated in both point-to-point and PCB wired amps.

Tube fault LED indicator harness and amp chassis LED plate

The Bias Engine is wired to 4 LED indicators that permanently illuminate when the tube is faulty and ‘flash’ when the tube needs to be replaced. The LEDs sit on the amp chassis, surrounded by the LED plate.

Wiring harness and mechanical fixings

The wiring harness, bundling all necessary wires and connectors, completes the kit along with a full set of mechanical fixings for securing the Bias Engine.

TubeSync Bias Runner software

Improving amplifier biasing methods, servicing and fault diagnostics

Interfacing with Bias Engine hardware, our Bias Runner software has been designed to allow OEMs and professional amp technicians to interrogate the status of an amplifier, alter bias settings, perform field diagnostics and configure the amp for best performance, further adding value to your services.Bias Runner_02

Bias Runner is easy to install, offering full fault diagnostics, enabling tube biasing with and without audio present, either collectively or as individual tubes. It is the perfect tool for warranty provision and servicing, providing a database of hardware serial numbers and storing amplifier parameter settings for full traceability.

Total service hours

Reads and displays the total number of hours the amplifier has been powered up. Optional reset facility available if required.

Total duration with audio

Reads and displays the total number of hours the amplifier has been driven with audio. Optional reset facility available if required.

Total hours idle

Reads and displays the total number of hours the amplifier has remained idle i.e. has not been driven with audio. Optional reset facility available if required.

Faulty tube log

Reads and displays the number of times a tube has been switched off due to a fault during the lifetime of the amplifier. A reset function is available for each individual tube.

Bias current (Audio present)

Enables the user to adjust tube current bias settings collectively or individually

Bias Current Idle (No Audio Present)

Enables the user to adjust tube current bias settings collectively or individually

Hardware and version status

Displays the serial number of the TubeSync module and the hardware version number

Serial number and settings database

Stores all serial numbers together with amplifier parameter settings in a   database for full traceability

Our commitment to you

We work closely with all of our partners to promote high standards and to support you in realising the full benefits of our truly innovative and impactful core technology and associated products.

As a TubeSync retailer or accredited technician you will receive:

Guaranteed product quality

All of our products are manufactured to the highest quality standards using state of the art assembly equipment. All components are ROSH compliant and uniquely identified for full batch traceability

A comprehensive solution

A complete package of hardware and software supports ease of use and easy configuration

Technical support

Our approach is founded on product and service quality. We offer our retail partners generous technical support to ensure that you are fully equipped for promoting TubeSync technology and advising your customers appropriately.

As an authorised retailer you will appoint a technician(s) who will receive training from our own technical team and who will be required to become certified as an accredited TubeSync technician before performing installations.

Warranty

All components come with a 12 month warranty which commences from the date of installation. Full warranty terms are available on request.

TubeSync Bias Engines Roll Off The Production Line

Friday, August 20th, 2010

Due to popular demand the TubeSync Bias Engine is now in volume production!

TubeSync

For order enquiries please email sales@tubesync.co.uk

Leaky Tubes / Valves Can Blow the HT Fuse In Guitar Amps, TubeSync Can Avoid This!

Thursday, July 1st, 2010

An interesting phenomenon that some ‘leaky’ tubes, removed from conventionally biased amps, appear to improve when run with TubeSync. The reason may be that when the tube gets hot, g1/cathode leak causes a current increase, but it is automatically biased ‘back’ to compensate, which allows the tube to cool down again and thus reduce leakage et al. After a while the leak sometimes reduces or disappears completely – we surmise that the getter  gets a chance to mop up stray gas molecules or the metallic deposit gets ‘boiled off’ the mica supports.  This type of fault in a conventional amp would normally blow the HT fuse, however TubeSync can avoid is and rectify the problem! Cool eh?

TubeSync_250

German Based Bulldog Amplification Approves TubeSync

Friday, June 11th, 2010

Bulldog Amplification builds handcrafted tube amps in Germany to meet  the ever demanding needs of musicians in terms of tone and reliability. Years of experience in repairing and modifying tube amps has lead to an exclusive line of guitar amplifiers. These instruments are built to produce the best possible tone. Most of today’s amps offer many different sounds and functions, but the guitar signal has to pass through various paths of electronic circuitry until it reaches the speaker, consequently the tone is weakened. Tone and bullet proof reliability are the most important things for Bulldog Amplification and that’s why Bulldog is delighted to announce that TubeSync will become standard within their The Jack 66, Jack 18, Black Bert 1, and Den Lachs amplifier models.

bulldog

The ‘’Jack 66’’

‘’The combination of TubeSync with short signal paths and other high quality components make our amplifiers world class and due to this, Bulldog Amplification is becoming a preferred choice by professional artists and serious guitar players’’.

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The TubeSync ‘’Bias Engine’’

‘’ Robust, bomb proof reliability, with enhanced functionality and perfect tone is what we want’’ – says Ingo Bührmann from Bulldog Amplification. Ingo goes on to say…

‘’Cheap poorly designed products from China are fast becoming unacceptable to guitar players especially within Germany, where high quality engineering is embedded within our culture’’ You would buy a car if the drive was terrible and it broke down when you needed it the most, well would you? ‘’ I believe the same philosophy applies to guitar amplifiers, high performance and reliability is paramount’’.

Bulldog Amps are currently used by a number of high profile bands such as the massively popular German band Guano Apes and Livingston. Bulldog amps with TubeSync will soon be appearing on a stage near you!

Guano Apes

Guano Apes

Liv

Livingston

For more information on TubeSync email:

UK: info@tubesync.co.uk

Germany: info@bulldog-amps.com

Hiwatt launch TubeSync at the Frankfurt Musikmesse 2010

Thursday, April 1st, 2010

Famed for their legendary reliability and tone, Hiwatt have gone one step further in the reliability stakes by employing TubeSync® technology in their already bulletproof amplifiers.

Over the last year, Hiwatt and Durham-based KBO Dynamics have developed their own version of a pioneering technology called TubeSync®, which Hiwatt will launch at Frankfurt Musikmesse 2010 in March. The technology has been developed in order to overcome problems associated with conventional tube amplification such as biasing, tube longevity and overall reliability. What the collaboration has achieved is to improve amplifier design without changing the fundamental amplification process yet retaining the classic Hiwatt tone and sound.

Hiwatt Launch TubeSync

Although not an integral part of the amplification process, Tubesync® is connected to the heart of the amp’s circuitry, constantly testing and monitoring; it’s like having an amp technician working full time inside the box every time the amp is powered up. This technology eliminates the need for tube bias current matching, increases tube life by micro-adjusting the bias on each tube, predicts tube failure and can, in the event of a catastrophic tube failure, even run the amp at half power. The result is the eradication of many of the problems hampering conventional tube amplifiers and peace of mind for the musician wise enough to have taken this route.

KBO Dynamics Chief Exec Andy Fallon: “It has been a pleasure working with Hiwatt who have been extremely receptive to change and have embraced the new technology. They have seen the benefits it can bring to them and of course, their customers, and we are looking forward to further exciting collaborations. This technology genuinely has raised the bar concerning reliability and classic tube amps, and what’s more. It’s been developed exclusively in the UK.”

Hiwatt logo

Guitar Amp Tubes / Valves The History Of .. EL34 s etc

Thursday, March 18th, 2010

Until the introduction of the germanium transistor in the late 1950’s, there was no alternative form of high quality audio amplification to the thermionic valve (American terminology was always ‘Tube’). The 1960’s, 70’s and 80’s saw a steep decline in the usage of valves for all purposes except audio amplifiers, to the point that, with a few exceptions, they were almost entirely replaced by transistors and integrated circuits. However, since the late 1980’s, valve amplifiers have experienced a renaissance which has, in the last decade grown rapidly year on year.

The unique character of the ‘Tube Sound’ has once again attracted both amateur and professional interest in the areas of High Fidelity (HiFi) amplification, Musical Instrument (MI) amplification (notably the electric guitar) and Audio amplification. The dominance of digital technology now, means that the valve amplifier is seen as new to younger people and as nostalgic to the older generation. Please note it is estimated, that the electric guitar amplification market consume as many as three out of four of the world’s production of audio tubes.

EL34 Valve

EL34 Valve

Many arguments have been put forward as to why tube amplification ‘sounds’ better than digital. Some differences can be proved using measuring instruments, whilst others are down to the nuances of the human ear. Whatever the reason, evidence shows more and more listeners appear to prefer the sound of a tube amplifier.

The demand for tube amplifiers is rapidly growing, with products ranging from a few hundred pounds to several thousand pounds, depending on quality and output power, with tube sales worldwide currently standing at over $100,000,000. Today vacuum-thermionic devices hold sway over the US $100 million worldwide guitar amp business. One rough estimate shows a 10-percent-per-year growth in demand for tubes used in MI instrument amplifiers and high-end audio since the late 1980s, with no apparent slackening.

However, the problems with existing tube amplifier technology is that the circuits used are based on ‘classic’ designs developed in the 1940’s and 50’s and, although more modern technology has occasionally been applied, this is usually confined to regulating the power supplies. One of the principle disadvantages of existing tube amplifiers is that they are very inefficient in converting electrical power into audio power. This is largely due to the ‘classic’ methods of controlling them. All analogue high power amplifiers require a system known as ‘Biasing’ to be applied to them. This controls the output devices and prevents them from ‘Thermal’ overload and eventual destruction. It does, however, incur a heavy cost in loss of output power and increased heat dissipation. In addition valves also need to be used in ‘Matched’ pairs, in order to control distortion of the output signal. This process is time consuming and expensive when carried out on a commercial basis.

THE SOLUTION IS ……..

EL34

EL34

Innovation Winners Attracts Famous UK Guitar Amp OEMs

Wednesday, March 17th, 2010

KBO Dynamics are making their mark in the international music industry. They will be showcasing their technology with a number of major customers at the high profile international music fair, Musikmesse in Frankfurt this March. Hiwatt is just one of the world’s most prominent guitar amp manufacturers and KBO Dynamics are delighted to have TubeSync technology incorporated in their latest amp designs.

KBO Dynamics Win Innovation Award 2009

KBO Dynamics Win Innovation Award 2009

KBO Dynamics, winners of the Durham and Wearside Innovation Business Awards 2009, stated : TubeSync technology achieves unique benefits including vastly improved reliability and performance in tube amps.  Securing orders from Hiwatt and others is a significant achievement.

KBO Dynamics Power and Control Devices

KBO Dynamics Power and Control Devices

‘The scale of the companies that KBO Dynamics are working with is impressive. They have ambitious plans for growth and have been performing very well since receiving investment from us. KBO Dynamics is an excellent example of successful innovation coming out of the North East and is testimony to the region’s strong knowledge base,’ Dr Richard Exley, North Star Equity Investors.

­The company has also been supported with market research, manufacturer introductions and early product launch activity by think M., a leading strategic marketing and research agency specialising in technology and innovation.

Andy Fallon, KBO Dynamics, ‘think M.’s channel research played an important part in helping us to secure investment by providing the market evidence required to prove TubeSync’s growth potential. It helped us to refine our offering to amp manufacturers and was instrumental in getting us through the door at some really high profile organisations.’

TubeSync

TubeSync

As KBO look forward to Frankfurt they already have further collaborations underway and anticipate generating more interest from manufacturers, amp technicians and musicians alike. If you would like any more information on TubeSync technology, please visit www.kbodynamics.com.

Hiwatt Launches TubeSync at MUSIKMESSE 2010

Friday, February 19th, 2010

UK-based KBO Dynamics will be showcasing their pioneering technology with Hiwatt at Musikmesse this March. TubeSync® technology achieves unique benefits including vastly improved reliability and performance in guitar tube amps. Hiwatt have incorporated the innovation in new amp designs to further underline their already exemplary reliability.
musikmesse_2010
TubeSync streamlines with the amp’s circuitry to constantly test and monitor the amp without altering the fundamental amplification process, tone or sound. It eliminates the need for bias current matching, increases tube life by micro-adjusting the bias on each tube, predicts tube failure and can, in the event of tube failure, even run the amp at half power, preventing catastrophic amp damage.

The result is an amp unhampered by many of the problems associated with conventional tube amplification allowing musicians to enjoy classic tube sound quality without the frustrations.

Mark Lodge Hiwatt’s general manager stated ‘Our amps have proven their reliability year after year. Incorporating TubeSync technology has allowed us to raise the bar one step further. The benefits are of great value to us and our customers.’

KBO Dynamics look forward to more exciting collaborations this year. For more information on TubeSync, please visit www.kbodynamics.com

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