#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.

[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.

[linuxgamenews]

Bring the Epic Battle to Life With The Art of Flight

The Art of Flight bullet hell SHMUP game is due to makes its way onto Linux via Steam Deck with Windows PC. The game comes to life thanks to the dedication and hard work of the team at Et Al Games. Due to make its way onto Steam. The Art of Flight brings a fresh take on space action games. Instead of piloting just one spacecraft, you find yourself in command of an entire squadron. So you will have multiple spaceships that all move in sync, darting and weaving through the vastness of space. This isn’t just about shooting and dodging; it’s about coordinating a dance, where each move has the potential to change the outcome of an epic battle. Visually, The Art of Flight stands out. The choice of using water color aesthetics gives everything a dreamy, fluid quality. It's as if you're gliding through a mesmerizing artwork where colors blend and swirl. This isn't the crisp, digital look you might be used to; it’s softer, almost otherworldly. And it's all due to be playable on Linux via Steam Deck.

So we'll definitely be usable thru Proton as we're planning to release for the Steam Deck.

According to the The Art of Flight developer's email reply, there are no plans for a Linux port, but they will keep the option open post launch. What you can expect, proper Vulkan support via Proton. Complementing this is the The Art of Flight soundscape. Think of the strum of warm guitars and the rhythmic beats of drums that seem to pulsate with life. There's something deeply engaging about the audio; it's not just background noise. The most unique part is how it's responsive. As you maneuver your squadron, the music alters, echoing your moves. It's as if you're not just controlling spaceships but also designing a dynamic musical composition.

The Art of Flight - SHMUP Fest Trailer

Challenges pop up in the form of episodic encounters. Each of these has its own spin, urging you to adapt and reconsider your The Art of Flight tactics. Navigating these waves becomes a blend of strategy and reaction, making every session feel distinct. Power-ups, when captured, grant your squadron enhanced abilities, broadening your approach to battles. Boss encounters amp up the challenge. Using a single ship against these titans would be a colossal task, but in The Art of Flight, you've got an entire squadron. Coordinate, strategize, and find those weak spots. For those who thrive on high stakes, the scoring mechanics are crafted to reward daring plays. Every decision, every move, could mean the difference between setting a new record or starting over. Local co-op introduces another layer. Collaborate with a friend, and the coordination reaches new heights. For those who prefer a more leisurely pace, or perhaps just want to immerse in the visual and auditory experience, there's the option to adjust the speed. This thoughtful feature ensures that everyone, regardless of skill level, can dive into The Art of Flight and enjoy it. In essence, The Art of Flight transcends typical space action experiences. It's an artistic journey, a synchronized ballet of ships, combined with strategic depth and immersive visuals and sound. For those who've ever dreamt of the stars, this offers a chance not just to fly, but to command, to orchestrate, and to truly experience The Art of Flight.

[avaqsemi]

NE5532 vs TL072: What are Differences and How to Choose 2023

The NE5532 and TL072 are both operational amplifiers (op-amps) frequently used in electronic circuits, but they have some differences in terms of specifications and performance characteristics. Choosing between them depends on your specific application requirements. As of my last knowledge update in September 2021, here are the key differences and considerations for choosing between the NE5532 and TL072 in 2023:

Noise and Distortion:

NE5532: The NE5532 is known for its low noise and low distortion characteristics, making it suitable for high-fidelity audio applications. It has a lower total harmonic distortion (THD) and lower input noise voltage compared to the TL072.

TL072: The TL072 is also a low-noise op-amp but typically has slightly higher noise and distortion levels compared to the NE5532. However, it may still be suitable for many audio and general-purpose applications.

Bandwidth and Slew Rate:

NE5532: The NE5532 generally has a wider bandwidth and higher slew rate compared to the TL072. This makes it better suited for high-frequency applications.

TL072: The TL072 has a lower bandwidth and slew rate compared to the NE5532, so it may not be ideal for applications requiring high-frequency response.

Power Supply Voltage:

Both the NE5532 and TL072 typically operate with dual power supplies, but they can also work with single-supply configurations with some limitations. Be sure to check the specific datasheets for voltage requirements and limitations.

Input Bias Current:

The TL072 usually has lower input bias current compared to the NE5532. This can be important in applications where input current offsets can impact performance.

Price and Availability:

The TL072 is often more cost-effective and readily available compared to the NE5532. If your project is cost-sensitive, the TL072 may be a preferred choice.

Application Considerations:

Choose the op-amp that best suits your application's requirements. If you're working on audio equipment or other high-fidelity applications where low noise and distortion are critical, the NE5532 may be the better choice. For less demanding applications or when cost is a factor, the TL072 can be a suitable alternative.

[teardownit]

The Cheapest and Simplest Audiophile Headphone Amp

This small amplifier finds its use not only with headphones for listening to your favorite tunes in good quality or for playing the electric guitar without causing any annoyance to your close ones.

It can also amplify line-level audio if any of your audio system components have too low sensitivity or output levels.

Our amplifier also has a low output impedance and a reasonably high input impedance—50 kilo-ohms. So, the amplifier serves dual purposes as a buffer with gain and as a power amplifier for headphones.

The design is inexpensive and quite compact, so it can be used in almost any project. The bipolar power supply is not required; any stabilized power source or 12 to 18-volt battery is sufficient.

This amplifier has a linear stereo input, not a Hi-Z instrumental input, for connecting an electric guitar. Therefore, if you play the guitar, you will need an additional preamp.

Headphone amplifiers are assembled using transistors, tubes, and microchips. The tubes add a pleasant warmth to the sound by adding even harmonics to the signal. We have already looked into this in a post on the DIY tube amplifier.

That sweet little amplifier is an excellent buffer for a hi-fi audio system. It can happily work with an electric guitar. But its output power is not enough for headphones. (Yet it can be an excellent preamp for our headphone amp today.) A tube amplifier needs to be powered with an AC transformer, which is not a portable solution.

Discrete transistor amplifiers can be decent, but they contain many elements. They need to be carefully configured, pairs of transistors with the same parameters must be picked, and a large quantity of high-quality capacitors must be used.

Some audiophiles say the best sound is created only with special carbon-fiber resistors. If the influence of the design and materials of capacitors on the quality of sound reproduction is objectively proven and has been measured, valuable parameters for resistors, from a technical standpoint, are accuracy and temperature stability. Metal film resistors are primary candidates, as they are known for this feature.

If you didn't already know, low-power carbon resistors are usually beige (modern film) and brown (vintage composite), and metal film resistors are often blue. But there are many exceptions.

Be that as it may, music is for pleasure. Music is an art, and this applies not only to composing and performing but also to playing back, listening, and making musical instruments and equipment. Therefore, subjective opinions and feelings must be respected because music is just about them. And the components should fit the person who creates the amplifier and the person who will listen to it.

Any way you approach it, creating transistor and tube amplifiers costs money and time, takes up space, requires skills, and sometimes requires special equipment for adjustment. Integrated circuits make everything much more compact, accessible, and simpler.

And if we talk chips for audio processing, first, we need to discuss operational amplifiers.

By the way, LM386 is an op-amp, too, designed to work with a loudspeaker or a headphone. I'm sure you've already used LM386 on your devices. Clearly, it is not at all an amplifier for high-quality sound reproduction through headphones or a small speaker.

Although, oddly enough, with a large 12-inch guitar speaker (not the 80-watt Celestion Seventy 80, better something like a 25-watt Greenback), the LM386 can sound very good in the room, it has just enough volume to be used as a bedroom amplifier.

But guitar amplification is a totally separate thing. You need to amplify specific guitar frequencies; the LM386 can handle this fine. And when you need to reproduce with high fidelity the sound of an entire orchestra, a rock band, or birds chirping in the forest, you'll need something bigger.

So, we will use NE5532.

The best op amp for audio

"There is probably no music on the planet that has not passed through a hundred or more 5532s on its way to the consumer." Douglas Self, British electronics engineer.

Please do not confuse NE5532 for NE532. The NE532 is just a complete analog of the good old LM358, developed in 1972 as an industry standard for operational amplifiers.

Surprisingly, the LM358 circuitry is built into many other integrated circuits. For example, the TL494 PWM controller contains two error amplifiers constructed according to the LM358 diagram.

We often use the LM358, sometimes even for audio processing, but in most cases, we still prefer the TL072 and NE5532. Why is that? This is precisely what we will talk about today.

NE5532 are considered operational amplifiers for enthusiasts, and rightfully so, one can find them in even the most expensive and prestigious audio equipment. From 1979 to 2007, that is, for 28 years, NE5532 was unattainable—the best in class! And then LM4562 came along.

There are several more expensive and more advanced operational amplifiers for audio, including those assembled on a printed circuit board from discrete components rather than an integrated chip design. After all, progress never stops, and there is no limit to perfection.

In fact, in the vast majority of cases, the characteristics of the NE5532 are more than sufficient for high-quality audio signal processing. This is confirmed by its application in various professional music and sound recording equipment and household high-fidelity audio systems.

This is all thanks to the fact that the NE5532 has very low noise, extremely low harmonic distortion (THD) with an appropriate switching circuit, and, very significantly, a high slew rate. It is equal to 9 V/uS versus 0.3 9 V/uS for the LM358.

It would seem that even LM358 has a gain bandwidth of 1 MHz (according to datasheets from different manufacturers, from 700 to 1200 kHz). However, gain bandwidth does not mean the effective gain band but just the frequency at which the unity gain is preserved.

When the voltage is amplified by +20 decibels, i.e., 10 times, the LM358's gain begins to decline already at a 10 kHz frequency. In contrast, for the NE5532, this frequency is 200 kHz.

Why does an audio signal need wide bandwidth anyway? An average human cannot hear sounds with a pitch above 20 kHz. Besides frequency, the attack of sound matters. The wave's shape matters, too, and to avoid distorting it, you need a bandwidth 10 times wider.

So, our amplifier is called "47" and consists of two identical channels - left and right. Each channel is built on a dual NE5532 operational amplifier. Resistors R1 and R2 divide the supply voltage in half, forming a common virtual ground for both channels.

Op-amp U1A is used in a non-inverting configuration: the input signal is applied to the non-inverting input, and resistors in the feedback loop set the gain from the output to the inverting input.

In our case, the coefficient equals (4.7 + 10) / 4.7 = 3.13, 9.9 dB.

Operational amplifier U1B is connected as a repeater with unity gain and simply doubles the channel output current. Resistors R8 and R9 limit the current to protect the headphones and amplifier.

The second channel is assembled according to the same diagram as the first one on a separate U2 chip. If you don't need a second channel, you can build just one using one chip.

This amp sounds very clean. Unlike guitar equipment, it does not alter the sound but simply reproduces the input signal with high quality.

So, high fidelity is not always difficult and expensive. Sometimes, you can achieve excellent results simply by finding a suitable scheme.

[audio-luddite]

Killing time.

I have an FEA running on my other computer. Got nothing to do until it finishes. An FEA is a computer analysis of in this case a large composite vessel. Such is my daily life.

So to occupy myself I look around and see an ad for a nice amplifier in the Classifieds. It is an ARC solid state unit, a D100A. Back in the day it caused confusion and consternation with the golden ears. It may have been the best amp ARC ever made up till that day in the 80s. 100 Watts per channel with not a tube anywhere. ARC no tubes WTF!?

The ad claimed it was fully benched and redone and brought up to spec with everything old and tired replaced.

But.

This was from the era when ARC tried to leave tubes behind. They created "analog modules" which were basically big Op-Amps made from discrete components cast into blocks to hide the contents. These things were intended to behave like tubes. at least that is what the marketing said. Glassheads slagged them hard. For that reason they are less desirable (cheaper) than tube stuff. They will also be impossible to repair if one of the modules cooks. There is no record of what went into the various types. ARC cannot help you.

But.

It has the usual ARC level of engineering and build. If all you care for is performance it is desirable. The golden ears said it had greater clarity and drive than their favorite at the time, which was another big ARC amp with tubes. It had no vacuum, no magic, confusion reigned. Yet it sounded really good.

This is the nexus of tubes versus transistors fight. If "tube sound" is your vision of perfection downgrade the new kid. If accuracy and neutrality is the goal, sign up for one.

It is not perfect. A similar unit was tested by those Geeks in Seattle (I think they are in Seattle) Audio Science Review. It came out less than great as it had distortion less than but similar to tube units. In their tests all tube units do very badly. ARC was trying to keep its voice I guess.

I have said a few times I am a fan of ARC. A fan is a person with an irrational motivation to like something.