#audio op-amp

[drnk2nkss]

https://www.futureelectronics.com/p/semiconductors--analog--amplifiers--general-purpose/tl084idt-stmicroelectronics-6240253

Operational circuit, general-purpose op amp, Power op amp, operational amplifier

TL084 Series 36V 4 MHz General Purpose JFET Quad Operational Amplifier - SOIC-14

[dvd2ddard]

https://www.futureelectronics.com/p/semiconductors--analog--amplifiers--general-purpose/ts391iylt-stmicroelectronics-5181997

Amplifiers, what is operational amplifier, op amps, Operational amplifier chip

TS391 Series 36 V 400 nA SMT Single General Purpose Comparator - SOT-23

[guitarbomb]

Spurr Audio Sonic Explorers Pedals: A Journey into Space-Age Sound

Spurr Audio has recently launched an exciting line of pedals, the F-201 FET Preamp and Orbit-2 Fuzz, both inspired by the thrilling era of space exploration. These innovative devices promise to take musicians on an unprecedented sonic adventure. F-201 FET Preamp: Warmth Meets Space-Age Design The F-201 FET Preamp is a unique blend of the warm, rich sounds typically associated with tube technology…

[taperwolf]

So this is another Eurorack patch using external devices: here, my homemade cracklebox.

I built this thing quite a while ago; it's a copy of the classic STEIM Krakadoos design. Its oscillator exploits bugs in the design of the ancient μA709 op amp chip to produce squelchy and crackling sounds when you touch the brass buttons on the left hand side. I've been intending to supplement the audio output jack on it, which is directly wired into the discrete amplifier circuit, with an output transformer; I've been told that doing that will make it so that plugging it into something doesn't couple that amplifier to the internals and change the sound.

But I decided tonight that before making any modifications, I should try plugging it into the sync input of my VCO 3340. This audio clip is the result: a solid chip oscillator being intimately tied to a weirdo.

The original zwoopy bounce is the patch as it stands without sync added, and then I turn the Cracklebox on, soft-syncing the VCO first with the ultrasonic base waveform of the Cracklebox, and then going through varying pressure on different patterns of touch knobs. I flip the Cracklebox off in the middle and switch to hard sync before going through the process again.

[teardownit]

DIY Dumble-like sounding MOSFET Overdrive

The Hermida Zendrive guitar pedal we will study, assemble and listen to today is a true masterpiece. Many say its sound is close to the Holy Grail of guitar amplification - Dumble Overdrive Special.

Other people are more pessimistic in their judgments. Still, the precise response to the picking dynamics, the Voicing tuning options, and the sheer beauty of this overdrive's sound are simply impossible not to love.

But before we study the Lovepedal Zendrive or its copy of the Landtone Phoenix song, or the Aion effects Azimuth dynamic overdrive, we'll study the evolution of the MOSFET overdrives that finally resulted in the development of this gem.

Fulltone OCD

Mike Fuller was one of the first to start using MOSFETs instead of diodes to limit the amplified guitar signal in 2004.

His Obsessive-Compulsive Drive overdrive-distortion pedal is built on a standard circuit with one dual op amp. The first operational amplifier, X1, amplifies the amplitude of the guitar signal by a factor from 8 to 463 times, depending on the position of the drive control X3. This is a 1-megohm potentiometer.

Further, through resistor R9, the signal is fed to the limiter, which comprises 2N7000 MOSFETs M1 and M2 connected in parallel. A germanium diode D1 - 1N34A is additionally included in series with M2, which makes the limiter asymmetrical and, therefore, makes more interesting sound.

A limiter in overdrives is usually included in the negative feedback circuit of an operational amplifier (i.e., in parallel with C6). Such a limiter is called a soft limiter.

And here, a hard limitation is applied: clipping sections are included between the preamplifier output of the gain section and the virtual ground - half of the supply voltage Vref, formed by resistors R4 and R7.

Virtual ground is used in the unipolar powering of operational amplifiers to amplify analog signals, such as audio signals. The guitar signal does not change from zero to plus but from minus to plus, passing through zero.

To prevent the signal from being limited to the circuit's ground, it is shifted in the plus direction by half the supply voltage.

Such hard limiting is typical for distortion pedals. But by using MOSFETs instead of diodes or LEDs, the top of the signal is not cut hard but softly rounded. Therefore, OCD can work as both distortion and overdrive.

Due to the smoothed peaks of the limited signal, the sound is highly dependent on the sound's attack dynamics. For rock and especially blues, this is very valuable. With modern metal pickups that compress the dynamic range of the signal, it can help make solos sounding more sweet.

The second operational amplifier X3 amplifies the limited signal by a factor of 3.8, correcting its timbre. Capacitors C6 and C9 prevent the self-excitation of operational amplifiers at high frequencies.

Next is a simple passive tone knob, which implies a treble leak circuit. Potentiometer X4 10 kilohms and capacitor C11 47 nanofarads are connected in the same way as on the pickguard of any electric guitar.

The Switch1 switch changes the circuit's output impedance as if the high-impedance and low-impedance pickups were switched. When it's open, you get a transparent overdrive like the Klon Centaur, and when it's closed, you can get a more aggressive sound like the Marshall Plexi.

Hermida Audio Zendrive

The Zendrive pedal's authors, Hermida audio technology (now produced by LOVEPEDAL LLC), have undoubtedly studied the Fulltone OCD thoroughly. Let's find the differences between the two circuits.

First, the limiter is included in the operational amplifier feedback, that is, between the output and the inverting input, not between the output and virtual ground. That is, here we have a soft limiter.

Secondly, one diode is added in series with each MOSFET. Clipping remains asymmetric: we have one diode in the left arm of the limiter and two diodes in the right arm.

Third, the second operational amplifier is used as a voltage repeater, aka buffer: the output is directly connected to the inverting input.

Fourth, the tone control is implemented a little differently: two OCD`s switchable resistors are replaced by a potentiometer.

And finally, the most critical, fifth difference. A potentiometer is included in the tone correction circuit between the inverting input of the first operational amplifier and the artificial midpoint.

This fourth knob, Voicing, or Character, allows you to smoothly adjust the lower frequencies in the overdrive structure over a wide range, similar to the Resonance control on many tube guitar amps.

The potentiometer is signed as a trimmer in the diagram because some pedal makers don't want to install a fourth knob on the pedal`s body. This is what Landtone did when developing the Phoenix Song Overdrive DIY kit.

The developer suggests installing the trimmer on the PCB, and to access it, you need to disassemble the pedal by unscrewing the footswitch nut and taking out the PCB.

But I will not be lazy to drill an extra hole in the pedal body and install a potentiometer with a knob, connected to PCB by wires instead of the trimmer. Because I consider this regulator simply invaluable and irreplaceable.

Before we get to assembly and testing, let's look at another pedal with a similar adjustment. However, it is based not on the Fulltone OCD but on the Ibanez Tube Screamer.

The Precision Drive

This is a signature pedal by Misha Mansour of Periphery, manufactured by Horizon Devices. Compared to the original Overdrive Pro TS808, the circuit adds a noise suppressor, which we will not consider, and an exciting ATTACK switch.

The Precision Drive scheme was studied and partially replicated by PedalPCB and PCB Guitar Mania. They are manufacturers of DIY kits for guitarists. Their products are called Dwarven Hammer and Collision Drive, respectively. A noise gate is not provided there, but the attack switch is implemented. This is the main difference between Precision Drive and many other overdrive pedals.

In the Fulltone OCD schematic, we saw a resistor switch at the tone shaping circuit in the output section. The Zendrive has a variable resistor in the preamp's RC circuit which is controlling the overdrive structure.

Precision Drive has a constant resistor in the same place, between the inverting input of the overdrive section operational amplifier and the virtual ground, but the capacitors are switched.

This is the same thing: we change the time constant of the RC circuit, which adjusts the audio signal's frequency spectrum. At the same time as the time constant, the complex impedance changes, thus the gain.

A resistor is a resistance to both DC and AC current. At the same time, a capacitor is only resistant to AC current because DC current does not flow through a capacitor. Since DC current does not flow through our RC circuit, there is no difference between adjusting the resistance and switching the capacitance.

But the active/reactive ratio affects the circuit's Quality factor, i.e., its resonance. It's no coincidence that the knob on guitar amplifiers, which adjusts the same frequencies as our potentiometer or switch, is often called RESONANCE. And it is used to adjust to the resonance of the electromechanical system - the loudspeakers in the cabinet, along with the masses of air in and around it.

The reactive impedance accumulates energy and gives it away, except for losses due to dielectric recharging and magnetizing the magnetic core in inductors. This is why coreless inductors are often used in high-end equipment, so-called air inductors. They weigh a lot, take up a lot of space, and are expensive because copper is more expensive than steel. But these are the laws of physics on which technology is based.

Unlike reactive impedance, active resistance converts electrical energy into heat, thus reducing the Q-factor. In some cases, it is necessary and useful. In others, it is harmful. Or it simply creates a unique sound character.

That's why switching capacitors and turning the potentiometer knob in the feedback circuit of an audio frequency amplifier is almost the same thing, but not quite. And it's great that there are such different variants of guitar overdrive pedals!

Landtone Phoenix Song Overdrive

Now you can hear how my Zendrive from the Landtone OD-1 kit sounds, with a Seymour-Duncan SH4 humbucker on a Gibson MM Explorer guitar, into an Orange MT20 with a Torpedo Captor X. And see how I assembled the pedal and also a kitten walking around the table and prancing around.

I liked the pedal, especially its fourth magic Voicing knob, which does things to the sound that other tone controls can't. I also liked the bird on the body. Because I love birds. And in the music world, the decoration of instruments and hardware plays no small role because it inspires creativity. And the fact that the pedal is assembled by my hands also warms my soul and creates inspiration.

[teledyn]

The computer is the same, and omg this fucking phone but what is sadly a most damning feature of this engineering oversight is that the feedback circuit to effect automatic master output volume leveling is mindnumbingly trivial, a single op amp.

We have desktops, even on multiple gamma-corrected monitors, and all apps work fine. My phone has five audio channels and "ok Google set volume 20%" only affects one of them.

I am so incredibly tired of having to watch all TV shows and movies with a remote control in my hand and my finger on the volume buttons!

The music and sound effects are soooooooooooo godsdamned loud and the dialogue is too quiet. I've a constant need to raise and lower the volume so as not to burst my eardrums. It's infuriating.

Please, for the love and peace of eardrums everywhere, balance the audio!

[stgeorgegourmet]

Top 10 Must-Have ICs for Your Next Electronics Project

Integrated Circuits (ICs) have revolutionized electronics, making complex circuitry compact, affordable, and more reliable. Whether you’re working on a hobby project or designing a professional application, certain ICs are essential for building efficient and functional devices. Here, we’ll go over ten must-have ICs that can elevate your next electronics project.

1. 555 Timer IC

The 555 Timer is a versatile IC known for its wide range of applications, from timing to pulse generation. It’s used in both monostable (one-shot) and astable (continuous) modes, ideal for creating oscillators, timers, and even light flashers. It’s a staple for DIY electronics projects and is compatible with numerous applications.

2. LM317 Voltage Regulator

The LM317 is an adjustable voltage regulator IC that provides a stable output. This IC can regulate voltages from 1.25V to 37V, making it essential for power management in electronic circuits. Ideal for custom voltage needs, it’s useful in battery charging circuits, power supplies, and adjustable voltage systems.

3. ATmega328 Microcontroller

This microcontroller IC powers Arduino boards, making it a favorite among hobbyists and professionals alike. It’s programmable with various I/O pins, analog-to-digital converters, and PWM capabilities, perfect for projects that involve data processing, motor control, or IoT applications.

4. Operational Amplifier (Op-Amp) IC: LM741

The LM741 Op-Amp IC is a general-purpose operational amplifier widely used in analog electronics. It amplifies weak signals and is commonly employed in sensors, audio applications, and signal processing. With a wide frequency response and minimal distortion, it’s an essential IC for audio and measurement circuits.

5. 4017 Decade Counter IC

The 4017 Decade Counter is a popular IC in applications where sequential LED lighting or timing control is required. It’s often used in combination with the 555 Timer to create light chasers or display counters. This IC finds applications in counters, timers, and LED displays.

6. ULN2003A Darlington Transistor Array

For projects involving motors, relays, or high-current components, the ULN2003A is invaluable. This Darlington transistor array provides the necessary current amplification to control multiple loads from a single microcontroller or sensor. It’s often used in stepper motor drivers and relay control applications.

7. NE5532 Audio Amplifier

The NE5532 is an audio amplifier IC with excellent noise performance, making it ideal for high-fidelity audio applications. Its low distortion and wide frequency response suit it well for audio mixing, preamplifiers, and general sound processing tasks. Audio engineers and hobbyists alike rely on this IC for quality sound amplification.

8. LM3915 Dot/Bar Display Driver

If you’re creating visual indicators, the LM3915 is a great choice. This IC is used to drive LED bar graphs or dot displays, making it a favorite for visual VU (Volume Unit) meters or battery level indicators. With its easy cascading options, it’s well-suited for applications needing multiple LED levels.

9. MAX232 Serial Communication IC

The MAX232 is crucial for projects involving RS-232 communication. It converts signals from a serial port to signals suitable for TTL-based digital logic circuits. This IC is essential for any project requiring serial communication, like microcontroller-based systems or data transfer applications.

10. ESP8266 Wi-Fi Module

For IoT projects, the ESP8266 Wi-Fi Module IC is a game-changer. This IC provides Wi-Fi capabilities to microcontroller-based projects, allowing remote control and data monitoring. It’s widely used in smart home applications, sensor networks, and any project that requires wireless data transfer.

Conclusion

These essential ICs provide versatility, reliability, and functionality, which makes them indispensable in electronic projects. Whether you’re building a simple timer, creating complex IoT devices, or designing audio applications, these ICs are vital tools. Stocking up on these components will ensure your toolbox is ready for almost any project that comes your way.

If you’re looking to get started with these ICs, you can find a wide selection and Buy Electronic Components Online from Blizzcartz. For more details and the best prices, check out Electronic Components Online in India.

[aeliyamarineinsights]

The Role of Amplifiers in Industrial Automation: Enhancing Signal Strength and Precision

Introduction:

In industrial automation, a high quality amplifier ensures boosting of such signals across various control systems for transmitting data accurately without loss. A high-quality amplifier in amplifying weak signals from sensors and controllers provides the most necessary action of sending it over long distances without degrading. This is particularly crucial in high-noise electrical environments, where a quality amplifier would filter out interference from signals and maintain the clarity of signals to achieve sharp operations. From motor control to sensor data conditioning, high-quality amplifiers enhance the efficiency, accuracy, and stability of the system and are therefore an essential part of modern automated processes.

What is an Amplifier?

An amplifier is an electronic device that increases the strength, or amplitude, of a signal, be it a voltage, current, or power signal. This means that an amplifier can take a very weak input signal to a stronger output signal while maintaining all its characteristics at a greater magnitude. General-purpose amplifiers are used in most audio systems for low-level sound signal amplification, in communication systems for boosting signals over long distances, and for boosting control signals for motors, sensors, and other automated equipment.

Amplitude amplifiers are utilized significantly in industrial automation because they ensure that the signal would not degrade in integrity over long cable lengths or where electrical noise may get superimposed over it, resulting in distortion. It ensures the precise control and accurate reading, which plays an important role in the reliable automation and systems’ efficiency in achieving their objectives.

Types of Amplifiers:

Operational Amplifiers (Op-Amps): These are high-gain voltage amplifiers with differential inputs used for many functions, which include amplification, filtering, and signal conditioning. The operational amplifier amplifies the difference between two input signals and can be very versatile in electronics.

Power Amplifiers: These are designed to offer high power output to drive large loads, such as speakers or motors, through boosting both current and voltage.

Servo Amplifiers: Control servo motors where the position, speed and torque are controlled according to feedback from the system through dynamic modification of power to offer high precision motion control.

Current Amplifiers: Ample signal with negligibly small alteration in its voltage for such applications demanding a high current.

Instrumentation Amplifiers: Low noise, high precision and high output amplifiers to preserve the integrity of the signal in sensitive applications.

Audio Amplifiers: Amplifies the audio signals to the frequency within the audible range; they allow the provision of a high fidelity audio output with negligible distortion.

RF Amplifiers: They amplify the frequency between MHz and GHz in RF frequency to be used for various applications such as wireless communications, broadcasting, etc. It is used for several applications of radar.

Voltage Amplifiers: Amplifiers used to increase the level of voltage in a signal that will be used in some form of further processing or applied as driving power in another circuit.

Key Functions of Amplifiers:

Amplification: Amplifiers strengthen the weak signal so that it can be transmitted through the automated systems for long distances without loss of signal. This feature is required in order to maintain the clarity of transmission among sensors, controllers, and actuators in the vast industrial environment.

Noise Suppression: Electrical noise is a problem in industrial environments because it adversely affects signal accuracy. Amplifiers eliminate noise so that signals are cleaned and clear for reliable data transmittance and control.

Stabilization and Control: Amplifiers stabilize signals, thus preventing fluctuations that could disrupt operations. In specific applications involving motor speed, position, or torque control, this stability is crucial as consistent signals ensure smooth and accurate machine performance.

Power Adjustment: Amplifiers control power levels to meet the requirements of various components. For instance, power amplifiers offer high output power to drive motors or actuators, thus ensuring that these devices receive enough power to function effectively.

Signal Conditioning: In sensor systems, amplifiers condition and enhance signals so that they can be processed. Through signal amplitude alteration and filtering out anomalies, amplifiers ensure that proper data acquisition and processing are made possible.

Support for Long-Distance Transmission: Amplifiers ensure that the signal strength is not affected even if a long cable run is involved, and thus data or control commands are not lost on their way to destinations. This is a function of high importance in large industrial environments where signals need to cover large distances.

Precise Measurement: Amplifiers, particularly instrumentation amplifiers, amplify weak sensor signals in measurement applications to enhance the accuracy of monitoring temperature, pressure, or other critical parameters in industrial processes.

[audio-luddite]

Stuff you have never heard.

I have heard a lot of stuff. But there is far far more I have not. I will generalize if I have had experience with a particular class or brand or type of audio device. For example I will comment in general terms about tube amplifiers. I own or have owned three different examples of those for a lot of years. I will also comment on different Solid State amplifiers for similar reasons. I currently have three examples of those from different brands and generations.

I will reserve comment on stuff I have no experience with.

How many people of this era have actually heard an ARC Sp3 A1? I have. How about a Dynaco PAT 5 with the FET op-amps, I have. They were different, but really close. I also have heard the older ARC D76 tube amps. Really nice, but not perfect.

There are a lot of people who will freely slag stuff they have never heard. I get a bit twitchy when I have heard it, or know the context, and my opinion is opposite.

Recently there have been a few of the old ARC pure solid state amps listed in market places. The specific model the D100 discussed a few posts ago has three examples for sale around North America. One is for an attractive price, the others for "reasonable" prices. As I explained these have the orphan Analog Module parts that if failed cannot be supplied by ARC. I have dug into it and there are at least two sources that say they have developed replacements. One is in Malaysia and I doubt that one. The other is in the US and I think it has promise. If true these old beasts can live again. The risk is reduced.

The Context is that these were developed by a very very good designer who was satisfied with the results. You have to respect that.

Within the blogs discussing these parts there are several comments as to why would you ever fix these old amps? They were crap. That is not even true a little bit. The Stereophile article I attached earlier can be read as clearly liking the sound of the ARC D100. In many cases preferring it over the previous "reference" amplifier. There was a doubt in the publisher's mind as he felt more comfortable with the tube sound of the reference. He could not deny that it had great clarity and power for most application. If there was a problem it was a marketing issue and established customer's (and reviewer's) expectations.

My experience with the Dynaco 400 family is another case of unjust slagging. I know what the original sounded like. It was the peer of several big transistor amplifiers of the era and was respected by both Stereophile and the "Absolute Sound". I read the reviews back in the day and owned one for years. My current Franken amp is based on a Dynaco 410 black box. It reveals amazing details and space if they are on the recording. Definitely not crap.

There are numerous places that I have seen the whole Dynaco 400 family called names. I really doubt anyone making those comments ever heard a healthy one. The asking prices for those is rising.

You can also see that for Crown, and SAE, many other brands are similarly mistreated.

Any respected brand from the last 40 years can sound very good. The Harmon Kardon Citation 12 is very good at 50 ish years old. I have one. It is clean and smooth and detailed. It is not a super amp at only 60 Watts per side buy it is no slouch. In fact I soon have to pull the ARC Cl60 out of my rack as the weather is getting too warm. I can do a head to head to head with the tuber and my two transistor beasts. (The Franken-amp and the HK) That may be fun.

I have another transistor amp. It is a Carver 200T which frankly does not sound that good. It is healthy, and I use it in my AVS system for a subwoofer. Full range it has many tiny problems, the worst is audible cross talk appearing as fuzz in the center of the stereo image.

Any old unit needs checking out as parts age. Electrolytic capacitors are notorious as are some of the older resistors. If someone heard a sick unit well that is not a fair evaluation. It is a common thing with old stuff not a fundamental flaw.

Actually why call anything from a respected brand as crap or not that good? I am sure some mega-buck devices are not as good as the price, but that is a whole different type of attraction.

Getting back to old stuff I know that many products were called perfect. The ARC SP3 A1 was called "A straight wire with Gain" by Harry Pearson of TAS one of the demi-gods of golden ears. I assure you it was really nice, but never that. Things are never so simple.

I have a prejudice about McIntosh electronics. Have heard only a few examples of the tube amps, never any solid state ones for a loong enough time. Music came out. I just do not desire the brand. That is all I can say.

If you want to criticize something please define the context. If you have no personal experience then say that. Honesty is nice always.

[volersystems]

Harnessing the Power of Operational Amplifiers in Analog Design

Analog and signal circuit design is essential for countless electronic devices, ranging from smartphones and computers to medical instruments and automotive systems. Though digital technology often holds the utmost significance, analog circuits are necessary for processing and transmitting real-world signals with precision and efficiency.  Please check out this post and understand the fundamentals of analog and signal circuit design, exploring their significance and applications.

Understanding Analog Circuit

Analog circuits are electronic circuits that process continuous signals like voltage or current whereas the binary values represent the discrete digital signals. These circuits manipulate analog signals in different ways, including amplification, filtering, modulation, and conversion. Analog circuits are specifically characterized by their ability to represent and manipulate real-world phenomena accurately. That’s why these circuits are essential for applications that require precise signal processing.

Important Principles of Analog Circuit Design

An analog circuit design requires a deep understanding of fundamental principles and components. Some important concepts include:

Ohm's Law – This law describes the relationship between voltage, current, and resistance in a circuit.

Kirchhoff's Laws – These laws administer the behavior of current and voltage in electrical circuits, including Kirchhoff's Current Law (KCL) and Kirchhoff's Voltage Law (KVL).

Component Characteristics – They allow you to understand the behavior of passive components like resistors, capacitors, and inductors, as well as active components like transistors and operational amplifiers (op-amps). These components are important for analog circuit design.

Frequency Response - Analog circuits work within certain frequency ranges and require the consideration of frequency-dependent effects like bandwidth, phase shift, and frequency response.

Understanding Signal Circuit Design

A signal circuit focuses on signal transmission and processing that can range from audio and video signals to sensor data and communication signals. These circuits are essential for various applications, including telecommunications, audio processing, instrumentation, and sensor interfacing. Signal circuit design covers different techniques and components tailored to specific signal processing needs.

Applications of Analog and Signal Circuit Design

There are so many applications of analog and signal circuit design in numerous industries and technologies:

Audio Amplification - Analog circuits are useful in audio amplifiers to enhance the amplitude of audio signals for speakers, headphones, and other audio devices.

Data Acquisition - Signal circuits are used in data acquisition systems to convert analog signals from sensors and transducers into digital data for processing and analysis.

Wireless Communication - Analog circuits are integral aspects of wireless communication systems, including radio frequency (RF) transmitters, receivers, and modulators/demodulators.

Medical Instrumentation - Analog circuits are applicable in medical devices like electrocardiographs (ECGs), ultrasound machines, and blood pressure monitors for processing and analyzing signals.

Automotive Electronics - Analog circuits are also used for automotive systems for applications like engine control, vehicle diagnostics, and entertainment systems.

Conclusion:

Analog and signal circuit design is the fundamental aspect of electrical engineering that enables the precise processing and transmission of real-world signals in a comprehensive range of applications. Using fundamental principles, components, and design techniques, Voler Systems engineers can provide analog circuit design services to accommodate the diverse demands of modern technology. Though digital systems continue to advance, the importance of analog and signal circuit design remains paramount, integrating the physical world into the digital counterpart smoothly and effortlessly.

[apn-music]

Analog Obsession releases Color Bundle: Distox, PreBOX

Unleash the power of distortion with the Color Bundle, featuring two innovative plugins: Distox and PreBOX. Dive into a realm of sonic experimentation and discover new dimensions of sound manipulation. This bundle promises to revolutionize your audio processing experience.

Distox

Experience the versatility of multi-mode distortion with Distox, a groundbreaking plugin that combines a tube and an op-amp circuit with various op-amps and tubes. With features designed to empower your creativity, Distox offers: - Input and output controls ranging from -30dB to +30dB, allowing for precise level adjustments. - High-pass and low-pass filters with adjustable frequencies, enabling fine-tuning of the frequency response. - Two distinct circuits featuring three op-amps and four tube models each, providing a wide range of tonal possibilities.

PreBOX

Redesigned from the ground up, PreBOX is the ultimate preamp-distortion box offering unparalleled sonic versatility. Key features include: - Eleven selectable preamp models, each with its unique character and tone. - AGC (Automatic Gain Control) for input gain, allowing for smooth and consistent level adjustments. - Adjustable output gain for precise control over the signal level. - Selectable high-pass and low-pass filters with multiple frequency options for shaping the sound to perfection. Both plugins bear the hallmark of Analog Obsession, a guarantee of exceptional audio quality and meticulous attention to detail. Additionally: - The resizable interface ensures optimal user experience, with the ability to adjust the size from 50% to 200%. - Clickable label for engaging oversampling (4x), enhancing audio fidelity and reducing aliasing artifacts. - Handy resizing tip for managing GUI size across multiple instances, ensuring consistency and ease of use. The Color Bundle is available in VST3, AU, and AAX Native formats, making it compatible with major digital audio workstations. Here are the system requirements: - For Mac users: Operating system versions 10.11 to 13.X are supported, with compatibility for both Intel and Apple Silicon processors. A graphics card supporting "Metal" is required. - Windows users: The bundle is compatible with Windows 10 and 11, requiring a graphics card that supports "OpenGL." Experience the transformative power of distortion with the Color Bundle. Whether you're a seasoned producer or an aspiring sound designer, these plugins offer endless possibilities for shaping your sonic landscape. Elevate your music production to new heights with Distox and PreBOX today. Download Link Read the full article

[where-i-bitch-about-nashville]

Melcor AML-27 restoration/racking 1RU stereo preamp

yoyoyo i got something done! i’ve been stuck on this thing and put it on thr backburner like embarassingly long ago and just went thru and got it back up and working:

Melcor Electronics Corp. AML-27 preamp cards, which were made circa 1965-1969 were sold in this backplane format, ordered or installed with fixed gain they were part of the ‘big green machine’ recording console as well as made with the RCA logo and branding for the same 1731 op amp used on these circuit boards. The 1731 uses 9 transistors. Melcor Electronics Corp/MEC still exists, and they made industrial microwaves and peltier coolers and stuff. MEC sold/ended their audio equipment division in a way that gave rise to Automated Processes, Incorporated, API. They still exist making consoles, and may even still make this format of preamp/line amp cards for all I know. It is 300mm not 500mm though, smaller than the popular 500-series lunchbox format. Anywho, API redesigned this whole thing with improved everything. They came up with the 2520 discrete op amp, which has been made along with its subsequent revisions in later years and is still the backbone of API consoles and outboard gear. The 2520 uses 11-transistors.the 400-17 and 400-20 transformers MEC used would be replaced with the API 2622 and 2623’s on their model 312 mic preamp. Or just the 2623, in the case of the 325 line amp card.

The AML-27 is a perfectly imperfect circuit design, lovely in its time, and it balances all of its various imperfections nicely… nay in an electronic sense, it absolutely juggles the metallurgy (and limitations of the transformer designs), op amp instabilities, feedback, gain, distortion, and overall resonance to make a really awesome fat sound. Compared to the API mic pre, it is much more lows and more third harmonic distortion. The distortion also becomes pretty soft clipping in the high gain settings. The API 312’s feedback lends itself to a more midrangey overall preamp sound. The whole sound comparison just boils down to sounding like the late 60’s vs the API sounding like early 70’s circuits, i dont have much better way to describe it. I read on the now-renamed gearslutz that Melcor circuits are all over the Frank Zappa and the Mothers of Invention album Uncle Meat.

My pair of cards was likely parted out from one of these old MEC backplanes around 6-8 years ago. I have serial numbers 012 and 936, but I have no idea their history before me!

For my part, I removed a PCB card kit build in 2010 that I took apart to rack these up, so everything is sort of prototype quality to get them usable and make sure they work right. It has way too many screw holes and scratched up paint, sharpie, and all kind of mess but so far I recapped the electrolytics, matched the feedback and built Grayhill 1073 12-position rotary switches with 1% metal film resistors for the stepped gain control. It has Bourns output attenuators, 110% shielded pure copper twist wire on all the audio path connections with quad 26ga +/- conductor wires. DC supply is on solid 22ga copper throughout, but retains the original Melcor card power LC filter instead of the diodes that were common on the later API mic pre designs that were based on this. I really paid a lot of attention to grounding, shielding, and cable routing, but turns out I did a terrible job back when I first hooked up the audio lines and need to redo it while spacing the cards out evenly in the chassis.

I got these cards stable up to 65dB of gain! :D I have a plan to get the 70dB stable without having to flip 2 switches, but it will have to wait until I can change to a multigang rotary switch.

So far I’ve fixed the input impedance at 600-Ohms, but I installed switches that will allow for the 3-way 300-, 600-, 1200-Ohm input strapping; i still have to wire that up. There is also already functioning 180° phase reverse, -18dB pad, and 48v phantom power on the input line. In the spirit of the 60’s prototype feel, I just went with directly wired mini toggle bat switches.

The gain and output attenuation knobs are a repro RCA skirted pointer knob scaled down to an appropriate size. The chassis is a 1U Middle Atlantic 8” deep steel puppy I got at Randolph & Rice in 2009 or 10 for the kit build. RIP Randolph & Rice Electronics, I miss them every time I build a thing… I am probably going to paint this with the vintage Melcor logo and the logo silhouette repeated as the eye slit in a stencil and possibly rattle-can likeness of the Big Bad of Tolkien lore, Melkor, aka Morgoth. AFAIK nobody else has seized on the company having a Tolkien themed name in arting up any mic pre builds… does anybody have any good Melkor art they’d want hidden in my rack??

So next I have to polish up my racking Valley People mic preamps project, and build an RCA tube console mic preamp pair from scratch of cobbled together vintage parts and new components. I’m also going to turn an Olsen Color Organ deathtrap box into a multiband filter/EQ, and make a clone Audimation Corp. EQ in an original Audimation EQ rack chassis. haha my work is cut out for me… but the mic pre’s will fill out my setup with a pair or two of every decade of noteworthy and/or Nashville linked sounds. for the early 60’s: something like what was originally installed at RCA Studio B, for the late 60’s: these Melcors, for the 70’s: API 2098 console pre’s modded out to the max for what is in RCA studio B now, the 80’s: Valley People/1979 Loft Audio 800 Console MPA5 made hy Valley People in Nashville, for the 90’s and 00’s: i feel like everyone was using protools and mbox interfaces and stuff that kinda didnt have much of a sound so im throwing in MOTU and RME transformerless preamps, and for the 2010’s: Miktek MPA-201, assembled in Nashville version of a rack pair of 1073 mic preamps using correct NOS transistors with 6 AMI audio transformers, dual metering, and lit relay switches for all the controls. 70dB of clean gain. 🔥🔥 I can pretty much make a recording sound like any of those decades with what I have, or combine it all for a mix with all this richness and character of some sick sounding mic and preamp combinations to do all the hard work up front!

[electronicsemi]

LM741 operational amplifier

The LM741 operational amplifier, an iconic member of the 741 series, has played a pivotal role in electronics for decades. Renowned for its versatility, the LM741 is widely utilized in various circuits, spanning applications from amplification to signal processing. This article aims to provide a comprehensive understanding of the LM741 op-amp, exploring its characteristics, applications, and practical considerations for effective utilization.

Key Features and Applications: The LM741 is a general-purpose operational amplifier known for its reliability and simplicity. With features such as a high input impedance, low offset voltage, and compatibility with a dual power supply, the LM741 finds applications in audio amplification, voltage follower circuits, instrumentation, and more. Its enduring popularity stems from its ease of use and adaptability across a broad spectrum of electronic designs.

Internal Structure and Pinout: Internally, the LM741 comprises transistors, resistors, and other components configured to amplify signals with high precision. Understanding the pinout is crucial for proper integration. The LM741 typically has eight pins, including inputs for inverting and non-inverting signals, power supply connections, and an output pin. A clear grasp of the pin configuration is fundamental for effective circuit design.

Practical Considerations and Limitations: While the LM741 is versatile, it has limitations, including a restricted bandwidth and common-mode rejection ratio. Careful consideration of these limitations is essential for optimal circuit performance. Additionally, external components such as resistors and capacitors may be employed to tailor the op-amp's behavior to specific application requirements.

Conclusion: In conclusion, the LM741 op-amp remains an integral component in the electronics toolkit, valued for its simplicity and reliability. Its wide range of applications and ease of integration make it an enduring choice for engineers and hobbyists alike. This article aims to serve as a guide for understanding the LM741, providing insights into its features, applications, and practical considerations for successful implementation in electronic circuits.

[teardownit]

DAC0832 Digital-to-Analog Converter

Digital-to-analog converters (DACs) are often built into microcontrollers but tend to be slow, noisy, and lack resolution. So, we frequently use specialized DAC chips.

Today's example is a digitally controlled voltage regulator module that could be used in a lab power supply. The workhorse here is the LM317T chip, which has the DAC0832 digital-to-analog converter at its core.

The DAC0832 is a pretty advanced chip, with not one but two latches arranged in sequence. This setup allows it to store digital data from the microprocessor bus and convert it to an analog value at just the right moment.

In the post about the 74HC374 latch, we used it to freeze the readings on seven-segment displays for a second while counting input pulses.

After a second, the data from the counters was sent out to the display decoders, showing the frequency of the input signal measured a second earlier. Meanwhile, the next count of pulses was happening. This made for a good frequency counter.

Each of the two latches in the DAC0832 can be made transparent, meaning asynchronous. In this mode, data from the input instantly appears in the output.

A logic high on the ¬LE (¬LATCH ENABLE) pin is needed to set the input latch to transparent asynchronous mode. You could call it LATCH DISABLE without the ¬ sign.

¬LE = ILE & (¬¬CS & ¬¬WR1) = ILE & ¬(¬CS | ¬WR1).

In simpler terms, you need a logic high on the ILE (INPUT LATCH ENABLE) input and a logic low on at least one of the two inputs, ¬CS (¬CHIP SELECT) or ¬WR1 (¬WRITE1). The ¬WRITE1 and ¬WRITE2 inputs are used for strobe signals.

For the 8-bit DAC latch register, the logic for ¬LATCH ENABLE is more straightforward:

¬LE = ¬¬XFER & ¬¬WR2 = ¬(¬XFER | ¬WR2).

So, you need a low logic level on at least one of the inputs: ¬XFER (¬TRANSFER) or ¬WR2 (¬WRITE2).

The heart of the DAC0832 is the analog-to-digital converter. This analog multiplexer switches precision silicon-chromium resistors deposited on a silicon chip.

This manufacturing technique ensures high accuracy and temperature stability, which is why we use DAC chips in our favorite high-fidelity audio gear.

Plus, a multiplexer can work much faster than pulse-width modulation (PWM) analog-to-digital conversion, which we often use in Arduino DIY projects.

Also, PWM produces square pulses with different duty cycles with a broad frequency spectrum. The frequencies might be inaudible, but their interference with other frequencies in the device can create audible noises, which can be pretty unpleasant.

The homemade tube amplifier article mentioned that asymmetrical and softly clipped waveforms sound pleasant and musical to human ears because they're full of even harmonics.

But a square, symmetrical waveform has many odd harmonics, which aren't so nice to listen to, especially when they create dissonance with the overtones of other sounds played at the same time.

The DAC0832 needs an external operational amplifier to convert the current through switched precision resistors into an output voltage.

We'd probably go with the NE5532 for audio output, which we used for a simple, affordable, and high-quality headphone amp.

But the good old LM358 will do fine for a power supply. Here, op-amp IC4A converts the output current of the DAC0832 into voltage, and IC4B amplifies the resulting signal by six times.

The TL431 chip generates the DAC0832's reference voltage, which is adjusted with the potentiometer RP1. The voltage ranges from 5×1100/1200=0.42V to 4.58V.

The output of IC4B is connected to the adjustment input of the LM317. Therefore, this chip's output voltage, and therefore our homemade power supply's, will be 1.25 volts higher than IC4B's.

So, the output voltage formula is:

Vout = 1.25 + 6 * Vref * DIGITAL INPUT / 256 = 1.25 + 0.024 * Vref * DIGITAL INPUT.

Adjusting the reference voltage can change the increment and decrement steps when pressing the corresponding buttons on the power supply's front panel.

The digital value for converting to a voltage is set by two 74HC193 four-bit up/down counters.

These are presettable counters, similar to the ones we used as registers in our DIY 4-bit CPU.

Each CPU's four registers used one SN74HC161L chip as a latch. The increment function was only used in the program counter (PC) register. The other three registers disabled it by grounding the CEP and CET control inputs.

We used the decrement function in a countdown timer that could be set to any number of seconds from 0 to 99.

Thanks to the preset function, the chosen value from the PRESET ROM of our electronic traffic light tells the second counter how long the current signal combination should last. The decrement function was also used there.

In today's power supply, we do not use the preset function but both increment and decrement counting. There's also a reset button to set both counters to zero.

Accordingly, the digital-to-analog converter will also be set to zero since both of its internal latches are permanently in transparent asynchronous mode.

To lock the chip in this mode, the ¬CS, ¬WR1, ¬WR2, and ¬XFER control inputs are soldered to ground.

We could make a power supply with non-volatile preset memory if we used a microcontroller instead of up/down counters. The microcontroller's analog-to-digital converter could be used for the voltmeter and ammeter.

And if the microcontroller doesn't have enough pins to connect the 8-bit DAC data bus, we could use a shift register for serial data transfer.

In this case, the DAC0832's latch registers could be very handy if the shift register doesn't have a built-in latch.

After all, to convert a binary number into a voltage, you must wait until the binary number is fully received from the microcontroller via the serial bus. Otherwise, you’d get meaningless voltage jumps, which are unacceptable in a power supply.