Coupling capacitor value tube amplifier

Users browsing this forum: Google [Bot] and 4 guests. Posted: Sat Feb 21, pm. How does one determine the size of a coupling capacitor between the stages of an amplifier? I understand the dielectric and quality have a large bearing on the sound of the amp. That the voltage rating needs to be above the actual voltage at that point in the circuit. I have a schematic which shows 0.

We are searching data for your request:

Wait the end of the search in all databases.
Upon completion, a link will appear to access the found materials.

Content:

• Welcome to TubeDepot
• Announcement
• Coupling & Bypass Capacitors
• ~ The QUAD II Valve Amplifier information ~
• The AM Forum
• If All Else Fails, Read This Article. Avoid Common Problems When Designing Amplifier Circuits

WATCH RELATED VIDEO: DIY tube amp, the coupling capacitor

Welcome to TubeDepot

There are a lot of mysterious components within any guitar amp, many of which remain puzzling even to hobbyists who have built a DIY project or two. Coupling caps are different from the electrolytic caps aka filter caps that we looked at in Part One of this series, in that rather than filtering electronic noise from the DC power supply, they connect signal-carrying components within the main part of the circuit.

As such, these caps are working like bypass caps—the bright cap on a volume potentiometer, for example, which lets more highs into the signal when the knob is in its lower range as you turn up that knob, the bright cap has less of an effect because more of the full signal is passing through the potentiometer anyway. Such bright caps can be connected directly between the input tab and wiper tab on a volume pot, as with the 47pF cap on the volume control in the Vibrato channel of a Deluxe Reverb, or on a switch that lets you take it in and out of the circuit, as with the pF bright caps in a Super Reverb and the like.

A lower-value cap passes less low-frequency content in the signal, while a higher-value cap passes more bass. In any case, any thoughtfully designed amp will be voiced by the consideration its maker has taken in which coupling caps are used at which stages, according to the frequencies that they accentuate or attenuate, in combination with the frequency response of the tubes affecting that stage, as determined by its plate and cathode resistors, any cathode-bypass caps used as discussed in Part One , and so forth.

The final sonic result of any chain of signal-influence components always depends, however, on the cumulative effects of those several different parts. Different types and makes might enhance warmth or brightness, perceived depth and richness, or very slightly alter the speed at which the amp reacts to your pick attack, and so forth. Javascript is disabled on your browser. To view this site, you must enable JavaScript or upgrade to a JavaScript-capable browser.

What Does This Thing Do? Written by Dave Hunter.

Announcement

What is a capacitor? The capacitor is one of the oldest electronic components. Electrical conductors where discovered in In the Leyden jar, the first capacitor, was discovered by Ewald Georg von Kleist, a German inventor. A Dutch physicist, Peter van Musschenbroek of the University of Leyden also discovered the Leyden jar independently in Currently, the Leyden jar is a glass jar with a metal foil coating on the inside and outside.

Coupling & Bypass Capacitors

F or those of us blessed with the inclination to build or modify tube electronics there is great reward in voicing your electronics with coupling capacitors that suit your taste. The same can be done with solid-state but generally these amplifiers are more complex so the impact of a single capacitor is lessened. In my experience capacitors reward attempts to voice a system more than interconnects do but not everyone is inclined or sufficiently skilled to take their amplifiers apart. I use single-ended power amps, these are low component count two-stage amplifiers driven from a sophisticated yet simple DHT preamp. My findings are applicable to tube push-pull amps too but the more complex an amplifier becomes then the less obvious the change of a single capacitor or pair of capacitors will be. From the get-go I will say that there will be no winner in the shoot-out. What is best for you depends on your taste and your system. One person may want a small amount of color euphony adding, others may want absolute clarity even if this could be uncomfortable to listen to at times. The ideal would seem to be a sound that is detailed, relaxing and dynamic; these characteristics are not easy to achieve in balance but with the right capacitor you can approach your audio nirvana. Let me also state that a great capacitor won't make a lousy amplifier sound good, indeed it'll probably make it sound worse as you'll hear more of what the amplifier is doing.

~ The QUAD II Valve Amplifier information ~

The Audio Voice Newsletter. Show more 9. Show less. May 26 , Another great research article from Ethan Winer, where he designed a simple device that measures capacitor distortion using a USB sound card and free software to try and determine the importance of high-quality capacitors in the signal path.

The AM Forum

For now the amp is working just fine, so my idea is to change at least the signal path electrolyte caps in the preamp - 3x10u polarized and 3x22u non-polarised Roederstein EKUs per channel with non-polarised WIMA MKS for example. For my philosophy the electrolyte cap are not sutable for signal coupling - for my ears they "color" the sound. I read the thread about the polyester caps and I have a question, especially for yachadm Menahem - I read that those caps could be changed with Wimas with much smaller values, I have never thought about that. Because the 10u Wimas are huge the space in Beomaster is small and expensive, what value and type would you recommend? And how about the CD, the huge russians? You can never replace a capacitor with a much smaller value.

If All Else Fails, Read This Article. Avoid Common Problems When Designing Amplifier Circuits

Tubed preamp, DAC and CD player manufacturers anticipate their gear will be used to feed components with a wide range of impedances. Because of this, many will use output coupling capacitors larger than necessary for many components especially tube amps. While this makes perfect business sense for the manufacturer, as a hardcore solder-slinger, YOU have the ability to optimize your output coupling cap value to your own gear. The calculators above help you do this. Coupling capacitors are used to block D.

Hum is caused by the addition of AC mains power signal to the audio signal of an amplifier. The main sources of hum include AC valve heater powering, DC power supply ripple as well as electrostatic and magnetic coupling. This article will provide some insight into how hum is caused and what can be done to reduce it.

This article takes a look at how the simplest of the valve types, the triode, is put to work as an audio frequency amplification stage, and examines the process of coupling signals between stages while isolating their DC bias potentials using resistor-capacitor RC and other coupling methods, with worked examples for RC and choke coupled stages. Examples are also given of practical circuits for a 3W RC coupled triode amplifier, and a 5W pentode amplifier, and comparisons are drawn with solid-state amplifiers, particularly field effect devices. Old technologies rarely die out completely; there are niche uses and particular applications where the properties of a technology are unique. For instance, the stone age is long gone, but we still use stone. The iron age is long gone, but we still use iron. The steam age is long gone, but steam still plays a very important role in electricity generation.

Discussion in ' Audio Hardware ' started by allied , Nov 9, Log in or Sign up. Steve Hoffman Music Forums. Location: MI. Vintage tube amplifiers can perform as good as new high-end amplifiers at much lower cost even after rebuilding. Some or most stock vintage amplifiers do not sound great.

If you don't how to work on such equipment, work with someone who does know how, having them implement the changes you want to try. Bring a notebook and a pen, watch what your friend does maybe even bring a video camera , ask lots of questions, and take notes. Yes, you're in school, and the lessons you learn will not only help you to eventually do the work yourself, they could save several hundred volts from being discharged through your heart.