Discrete audio amplifier project PT20 Measuring distortion with computer JohnAudioTech 2026-09-23 | Discrete audio amplifier project PT20 Measuring distortion with computer
Angels Horn H002 BT turntable review - Good starter table with an issue JohnAudioTech 2024-06-16 | I test out this turntable and list the pros and cons.Amazon link: http://b.nxw.so/2LpawV15% off code ''Angels'' for Official website link: bit.ly/4czxqPCSupport this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Dealing with amplifier power on/off pop sounds JohnAudioTech 2024-06-13 | Some amplifiers make pop, click or thump sounds when turned on or off. Sometimes you can fix it, sometimes you can't. This video looks at some possible causes and solutions.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Phono preamp kit build and test - Elliott Sound Products JohnAudioTech 2024-06-03 | Elliott Sound Products site: sound-au.com/index.htmlPhoto Preamp link: sound-au.com/project06.htmPlease support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Oscillating amplifier - Tips to fix JohnAudioTech 2024-05-11 | If your vintage audio amplifier is oscillating, this video shares a few tips on how to determine the cause.Help support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Vintage Dual 1237 turntable plus what going on with this channel JohnAudioTech 2024-04-13 | I finally get a good turntable to play my records.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Solar eclipse - April 8th 2024 JohnAudioTech 2024-04-08 | Likely the only time I'll witness a total solar eclipse. I was fortunate enough to live in the "totality zone" and had only light clouds. Also fortunate to see it with my elderly parents. The shot at the end was using a camera with a tele zoom lens.
Douk Audio H7 Pro amplifier XLR level issue JohnAudioTech 2024-03-30 | After reading some comments from the review video, it seems the H7 Pro has a couple issues I need to address. I also added a couple extra measurements as well.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Douk Audio H7 Pro class D amplifier review (TPA3255) JohnAudioTech 2024-03-21 | Another class D amplifier review for you. This time it is a brand new product, the Douk Audio H7 Pro for $130 US. Let's see if it is any good.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
QuantAsylum QA403 Audio Analyzer first look JohnAudioTech 2024-02-23 | Finally got my hands on one of these as they have been had to come by due to stock issues. This video is an overview of the of the unit.QuantAsylum site: quantasylum.comSupport this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
The blue LEDs that existed before the current InGaN blue LEDs JohnAudioTech 2024-02-13 | Although a gallium nitride based blue LED was demonstrated in the early 70's, The silicon carbide based blue LED was the first commercially available. This video takes a quick look at them.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Transistor breakdown voltage demonstration JohnAudioTech 2024-01-25 | Bench test of transistor breakdown voltage Vceo, Vcbo and more.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
JAT501 amplifier hot rodded for more power JohnAudioTech 2024-01-14 | Boosting the voltage rails and minor changes to the JAT501 project amplifier for more power into 8 Ohm speakers.Link to JAT501 files: drive.google.com/drive/folders/17hZnd7lHIgxiF0vYiqyiVZeuyNLp8Kk0Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
1 By One turntable motor replacement and quick review JohnAudioTech 2023-12-23 | Speed was getting wonky on this record player, so I attempt to replace the motor and give it a quick review.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
DOUK AUDIO ST-01 Pro amplifier performance tests with teardown JohnAudioTech 2023-12-16 | A budget class D amplifier with tube stage in for review. Sells for around $125. Let's check it out!Douk Audio site: doukaudio.comSupport this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
DIY speaker project revival - PT1 enclosure volume JohnAudioTech 2023-12-06 | Time to get the speaker project going again but in a new direction.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
DIY bench lighting project - simple as it gets JohnAudioTech 2023-11-27 | I'm getting back into the swing of things but first, I need to get lighting on the bench at my new house with minimal effort.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Review of some cheap speakers JohnAudioTech 2023-11-12 | As I clear my life of the clutter, I wanted to test some cheap small bookshelf speakers I have. The worst ones get hauled off to the Goodwill store where they will probably price them the same as they cost when new.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Fosi Audio P3 Pre-Amplifier review & analysis JohnAudioTech 2023-10-30 | Fosi Audio gets another crack at it on the JAT channel. I never reviewed a preamp before. Let's see how this goes...Amazon US -amzn.to/3QwGsE1Aliexpress - https://s.click.aliexpress.com/e/_ok91hH7Fosi Audio Official - bit.ly/46P95BO15% off promo code: FAP3MKT15 (works for all platforms, will expire on 16th Nov.)Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Fosi Audio V3 on 48 volts - power measurement JohnAudioTech 2023-10-11 | Testing the V3 amplifier that normally comes with a 32 volt power brick with the optional 48 volt brick. Also checking the gain of the amplifier.My V3 review: youtu.be/b4wH-X2QufUSupport this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Changes in my life - the reasons Ive been gone JohnAudioTech 2023-09-18 | Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Amplifier modification to fix clipping asymmetry JohnAudioTech 2023-06-30 | Back on the Grommes Precision G-62 to see if I can correct the early clipping problem when driving 4 ohms loads.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Fosi Audio Class D amp - model 3V review - TPA3255 JohnAudioTech 2023-06-26 | Looking at another Fosi Audio amplifier. This new model just released, the V3 features quality components, swappable opamps and a better thermal design. Let's see if it is really any good.If you are interested in purchasing this amplifier:Amazon: amzn.to/45RBsiXOfficial purchase link: bit.ly/fosiaudiov3Aliexpress: aliexpress.com/item/1005005605031795.html12$ off promo code: FAV3MKT12 (works for all platforms)Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Grommes model G-62 commercial duty amplifier JohnAudioTech 2023-06-02 | Last of the audio equipment I brought home a couple years ago. This amplifier is designed for commercial use (Muzak, paging) in grocery stores, warehouses and the like. Let's check it out.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Carver m400t amplifier repair final JohnAudioTech 2023-05-18 | This amplifier has been sitting around for months needing me to finish the repair job on it. There is a problem with premature clipping on the negative peaks on one channel.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
TDA7268 amplifier video from 2009 - JAT Xtra content JohnAudioTech 2023-05-11 | This is a video from my old YouTube channel. Recorded March 2009. Snickers the cat popped in as usual.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Fosi Audio TB10D amplifier review JohnAudioTech 2023-05-06 | The BT10D amplifier (current price $77 us) has lofty claims. Let's test it out.Product Links:Amazon US：bit.ly/azustb10dAliexpress：https://s.click.aliexpress.com/e/_olV6A6ZOfficial website：fosiaudio.com/product/2-channel-amplifier/tb10d$15 off code: TB10DP15YTB (only for official website)Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Null test for comparing amplifiers JohnAudioTech 2023-04-28 | After modifying the SWTP Tigersaurus amplifier, a question was raised: How will it sound compared to the unmodified unit since they will be used together in a stereo system?Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
SWTP Tigersaurus amplifier modification completed JohnAudioTech 2023-04-22 | After modifying the output stage to not have gain (be a buffer), I modded the input and VAS stage to run at full rail voltage and then fix the bias circuit to work with the mods.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Amplifier feedback compensation and stability - JAT801 JohnAudioTech 2023-04-13 | I discuss amplifier loop stability and compensation and then test the JAT801 to see if it really has an issue.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
FNIRSI tablet style 2 channel oscilloscope model 1013D review JohnAudioTech 2023-04-08 | My opinion of this budget friendly battery powered oscilloscope. Current (April 2023) listed price (US) is $165.99 w/ 100x probe or $155.99 without the 100x probe (two 1x/10x switchable probes are included).Purchase links:Amazon: bit.ly/3Kd8no0Aliexpress: https://s.click.aliexpress.com/e/_okU6dwPAdvertised specs:Number of Channels 2Bandwidth 100MHzSample Rate 1GSa / sStorage Depth 240KbTimebase 50S / div~10nS / divVertical Sensitivity 50 mV / div~500 V / divInput Impedance 1M ohmTrigger Modes Auto / Normal / SingleTrigger Types Rising Edge / Falling edgeCoupling DC / ACHighest Test Voltage 1X : 40V / 10X : 400VCursor Position XY / Trigger YWaveform Manager Support (1000 pic +1000 waveform)Frequency Precision ±0.01%USB Export SupportPower Supply 6000 mAh lithium batterySupport this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
tigersaurus 210/A stability work - PART 2 JohnAudioTech 2023-04-01 | Tackling this oscillating beast.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
SWTP Tigersaurus 210/A amplifier oscillation problem JohnAudioTech 2023-03-30 | Vintage amplifier resists several attempts to be stabilized.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
JAT801 amplifier stability tests JohnAudioTech 2023-03-28 | Failure is okay. It helps you to learn.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Resistor bank dummy load for testing amplifiers - DIY build JohnAudioTech 2023-03-16 | It is time to upgrade my dummy load for testing amplifiers.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
SWTP Tigersaurus Amplifier 210/A power test & checkup JohnAudioTech 2023-03-12 | I have two Tigersaurus amps in. One is working, the other needs a lot of TLC. This is a checkup on the good amp.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
AM radio interference - seeking the source JohnAudioTech 2023-03-10 | Interference on the AM dial blocks out DX sources, so I go on a search for the cause.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
JAT801 audio amplifier assembly and first power up JohnAudioTech 2023-03-06 | I populated the board with parts and applied power. Will it work? Watch and see. Included are some tips for assembly.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Transistor case style confusion JohnAudioTech 2023-03-04 | Planning to assemble the JAT801 amplifier board but I got transistors that won't fit!Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Amplifier turn-on pop and audible noise - budget board comparison JohnAudioTech 2023-03-02 | Comparison of a few of these cheap amplifier boards / kits for turn on (and off) sounds and audible noise (hiss).Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
JAT801 amplifier and speaker design / build project updates JohnAudioTech 2023-02-26 | I received the prototype boards for the JAT801. Also discuss latest plans on the speaker project.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Speaker design and build project - Part 1 JohnAudioTech 2023-02-15 | I haven't built a speaker in over 10 years. Let's fix that!Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Tigersaurus 210/A amplifier schematic walkthrough JohnAudioTech 2023-02-04 | The Southwest Technical Products Corporation "Tigersaurus" was an ambitious high-powered solid-state amplifier from the early 70's. Boasting 200w into 8 Ohms or 250w into 4 Ohms and very low distortion figures for the time, it was sold assembled or as a kit. Although some claimed it worked fine for them, others had problems with it oscillating and/or burning out parts. I was helping a friend try to repair one (from afar) and I thought the design was interesting to cover in a video.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Badly corroded SATA power connector JohnAudioTech 2023-01-14 | I found this when removing HDDs from an old computer.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
JAT801 150 watt audio amplifier project - preliminary design PT1 JohnAudioTech 2023-01-08 | About time I get this going.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
LED Bulb burnout - what fails inside? JohnAudioTech 2022-12-17 | Analysis of 22 LED bulbs that burned out to find the most common point of failure.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Class G & H audio amplifiers - How they work JohnAudioTech 2022-12-14 | Part 4 to the "Introduction to Audio Amplifier Classes" video series covers class G and class H.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Class D audio amplifiers - How they work JohnAudioTech 2022-12-09 | Part 3 of the "Introduction to Audio Amplifier Classes" series.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Class B & AB audio amplifiers - an introduction - Part 2 JohnAudioTech 2022-11-28 | In part 2 of the introduction to audio amplifier classes series, I look into class B and class AB amplifiers.Note: Another bit of confusion is Class AB1 and AB2 which is for the biasing of vacuum tubes. I've seen people try to apply it to transistor amps which makes no sense to me.Misspelling note: should be "dissipation" in class AB disadvantages.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
Audio amplifier class introduction - Part 1: Class A JohnAudioTech 2022-11-19 | This video series is an introduction to audio amplifier classes and how they work. I have a few examples of simple class A amplifier circuits on my channel.Support this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
InfiRay Xview V2 thermal imaging camera review - Great tool for the bench! JohnAudioTech 2022-10-21 | Thermal imaging cameras have many uses and is great tech to have on the bench. Special thanks to Pergear for providing me one for review. For more info or to purchase this camera check the following:Amazon US: amazon.com/dp/B0B8P1576G?ref=myi_title_dp Amazon CA: amazon.ca/dp/B0B8P1576G?ref=myi_title_dp Amazon AU: https://www.amazon.com.au/dp/B0B8P1576G?ref=myi_title_dp Pergear: pergear.com/products/infiray-xview-v2More specs not mentioned in the video:Thermal sensor resolution: 192 x 256 (vertical oriented)Frame rate: 25HzVideo & still pixel res: 286 x 384WIFI: real time screen sharing to smartphoneRated battery life: 5hr per charge1 meter drop resistantIP54 water / dust proofProduct promotional video here: youtu.be/8teEmQKSa7USupport this channel on Patreon patreon.com/user?u=12254451Email: johnaudiotech@gmail.comThank You!
