Some are too quiet, and thus a threat to pedestrians. As a result, some have been made more noisy as a safety feature.
Probably related to the PWM circuit. You should hear the Harley-Davidson proto electric, it's earsplitting.
Apparently, that's a good thing. Rides nice, though. https://www.youtube.com/watch?v=vuhPZTrSmBw
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Funny about the car sounds; I remember seeing a "system" in a Warshawsky (JC Whitney) catalog that made your basic car sound like a hotrod. Somehow it was doubtful that a tiny amp with 4" surface mounted speakers could pull that off.
Until recently, the idea of a stereo in my car was a joke; the engine was the sound system...
But pertaining to the topic of the thread, it's always been my feeling that there was just too much demand placed on a tiny op amp die, with it's limited materials, to properly reproduce audio to the same effect that would be possible with dedicated, specialized components.
Again, just my opinion.
I would have hoped for more hybrid circuits that would maybe use an op amp within a circuit that also employs a separate transistor for an output, similar to what Burson has done with a new product.
Maybe if I would have gotten into this hobby sooner, I would find a way to measure for the "fatiguing" sound that come along with ic op amps.
Until recently, the idea of a stereo in my car was a joke; the engine was the sound system...
But pertaining to the topic of the thread, it's always been my feeling that there was just too much demand placed on a tiny op amp die, with it's limited materials, to properly reproduce audio to the same effect that would be possible with dedicated, specialized components.
Again, just my opinion.
I would have hoped for more hybrid circuits that would maybe use an op amp within a circuit that also employs a separate transistor for an output, similar to what Burson has done with a new product.
Maybe if I would have gotten into this hobby sooner, I would find a way to measure for the "fatiguing" sound that come along with ic op amps.
I had a little AM radio with 3 of the transistors on the board not connected to anything.
It looked more impressive that way, though. That made catchier magazine ads, too.
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Try a different kind of support, and a century.
(takes a heap of cunning Jesuit training to make a leap)
A lot of 'not found' searches. Not surprising, they were developed in the 40s!
We swapped the discrete transistor (metal can BC108 etc) card rack that drove the Magamps at Rotherham Primary mill and used some modern class B transistor audio amps to get the necessary volts to drive the magamps.
The control was surprisingly improved despite the magamps still in circuit. Control still sent through MG sets, Mercury arc rectifiers etc to the DC motors.
The operators had to retune their hands. The machine did what they instructed, not what they expected!
Swapping the whole lot out for modern thyristor DC drives on other mills gave surprising accuracy and the ability to auto-roll very difficult sections. The extremely crude (but unburstable) mechanics was the limiting factor.
Fitting a modern op-amp to replace the 1990s / mid range standard seems to be the same. Yes, specific applications have need for low noise, high stability, low offset or whatever. The standard slice of bread in 99% of applications - and you'll never know: because the clanky electromechanical and high power parts on the end will always swamp the .00005% THD or noise difference in the low level front end.
I just changed the TLO62 in my Bass guitar for an OP2277. Actually, the noise was coming from the worn 1/4" connector which I found whilst pulling the OP-Amp. I feel better and I'm sure it will have more presence, deeper quiet spots and more accuracy with the new amp
No, purely advertising. A fancy AM radio required an RF amplifier, an oscillator, a mixer, an IF amplifier or two, a detector, the first stage amplifier and a push-pull output. Eight transistors and a diode if done full blown and legit. High frequency transistors were often state of the art NPNs. Audio older PNPs.
The basic and most popular 6 transistor radio used a mixer oscillator, an IF stage or two, a detector, the first stage amplifier and a push-pull output. By using a transistor B-E junction for the detector diode they could call it a seven transistor radio.
Now as AM stations were fairly high power the RF stage was almost never needed. That was good because RF transistors of the day were noisy and very low FT. The basic tuning capacitor was two sections one for RF filter and the other tuning the local oscillator.
The output stage was transformer coupled to allow push pull drive with just PNP transistors. They were also transformer driven by a single preamp stage.
I probably fixed dozens of these in my youth. Motorboating was the common problem caused by a failed battery filter capacitor.
For advertising purposes they would try to add as many transistors as possible without screwing up the basic circuit. RF preamp-bad idea, extra IF possible 1 stage more but that was the limit for such strong signals. So there really wasn't much to do with the extra transistors except to put them on the board to increase the count.
Now Just for Marce, the PC layouts were all hand drawn with almost all curves and ink blots for three hole spots. Resistors were mounted vertically and the electrolytic capacitors were much smaller than the Sprague versions, also leakier.
https://www.google.com/search?q=6+t...=Tyg7WMy8JMeMjwSVxoiYCw#imgrc=1vXGJawIGyim8M:
Shows the typical schematic of a real 6 transistor radio with 2 IF stages.
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I have a complete KLH stereo system with the turntable and loudspeakers, if you are interested!
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