They inherited it from Agilent, who inherited it from Hewlett Packard, who bought eeSOF way back in the 1990s. In my last post, I showed several super simple, but very effective, tube circuits. Two P-channel FETs are used in the conventional differential amplifier input stage. 3, Number 2 of your magazine from one of my customers. Using a big battery unloads the power transformer, whereas rectifying a winding only further burdens the power transformer; in fact, even more than just running AC into the heaters.... Solid-State Email Tube-based, push-pull power amplifiers come in two basic types: transformer-coupled and OTL (output transformer-less). You can vary the coupling factor, then see what an ideal coupler does over frequency. Most electrostatic loudspeakers and headphones are crossover free; consequently, both deliver a far more coherent sound, free as they are of the yards of magnet wire and many capacitors and resistors in the average passive crossover.... Third-Order Active Crossovers In spite of the beefy triode and high idle current, balanced driving 300-ohm headphones was its limit. I hope to see many old friends and, perhaps, hear a few good sounds. In the last post, we saw a patent from NASA for Manuel Kramer's "Electronic Amplifier with Power Supply Switching," which was a class-H amplifier push-pull power amplifier. I have shown countless MOSFET-based Circlotron designs, which any google search will quickly reveal... CCCS ???? We have seen how to make a simple supercharged grounded-cathode amplifier, but the same technique could be applied to cathode followers or cascode amplifiers or White cathode followers or Broskie cathode followers, even, SRPP amplifiers. So if this stepped attenuator was so great, why did I stop selling them? Due to several requests for a PCB that held the 12Vac power supply from the 12Vac SRPP. The two-tube Circlotron is considered so inviolable, so sacrosanct that to posit an alternative is to blaspheme most egregiously. I can almost hear all those heads being scratched... Happy New Year! The LT1166 is ideally suited for driving power MOSFET devices because it eliminates all quiescent current adjustments and critical transistor matching. Is this really that good of news? We saw it back in blog number 211. Just do a web search on "Retro rocker clear glasses" or "Fashion nerd eyeglasses." It could, however, be much better... Chromecast Audio The PS-19 is a tad bit bigger, being 3.2 by 3.7 inches big. So, instead I created a 12Vac power supply that delivers a regulated 12.6Vdc (or 12Vdc) heater voltage. One possibility is that most classic albums are quite good.      22 Jun 2014. Good news. Between a passive line-stage and an active line-stage amplifier with gain, falls the active buffer line-stage that develops no gain. If you do a search on the web, you will no doubt find the following topology, as it is the obvious way to go... Sneaky NFB Two-Stage SRPP Amplifier Amazing Push-Pull Power Buffer By cutting the highs and boosting the bass, the phono stage’s inverse RIAA equalization of the LP’s RIAA equalization curve returns the signal to flat. In contrast, the feedback-based shunt regulator sees only the disturbance on the output side of the series resistor. How do you get 120Vdc out 12Vac? I was searching for single-ended amplifier schematics—tube-based single-ended amplifiers—when I encountered the following circuit in my huge stash of SPICE circuits that I have created over the last twenty years, which is a super-triode design that holds triodes and transistors. Fortunately, Bjørn, a reader in Norway, sent me a list of errors. He didn’t need a lot of gain and he wanted to experiment with different ultra-linear ratios, so I recommended the following circuit as a useful test bench and starting point.... Ultra-Linear Cascode The Aikido PH-1 is an excellent tube-based phono stage. Was it just one decade ago or is it closer to three decades? Aikido Cascode How many times have you had to convert electrical degrees to length or delay? One of the best sellers at the GlassWare-Yahoo store is the Select-2 three-input signal selector switch and PCB. by what arouses keen interest in my posts. A solid-state Circlotron was patented in 1959 by A. W. Donald III. What if you wish to use 4-ohm drivers with 8-ohm drivers? Voltage regulators are high-gain, unity-gain amplifiers, which means that they are also high-feedback amplifiers... Push-pull class-A output stages are naturally clean, as sharp on-off transitions are excluded and the two output devices’ transfer curves combine in single flatter curve; additionally, class-A operation prevents the problems of switching distortion, gm doubling, and tweaky bias adjustments. But before digging into the details, we should mention the huge practical difficulties in testing cables sonically... My Interconnect History I like high idle current and class-A operation, but not the short output tube life span and the extra heat. Now we can stray far afield from established practice. Imagine a single 300B that could put out 200W, which will give you a good idea of what an ideal super-triode amplifier might be like.... DHT Super-Triode Sans CCS The differential amplifier accepts a balanced input signal and delivers a balanced output signal.