I'm amazed they went to the trouble and expense of patenting this---and spent years at it. The patent text also says it's an alternative to complex designs 🙂 They also emphasize low noise, which right off the bat is suboptimal with the emitter resistors in the input stage. Oh well. I guess the phase compensation is clever, after a fashion.
They even present a flow chart for how to do a specific design.
EDIT: Although AA is prone to sloppy wording in their blurbs, how does one separate the input stage distortion from the overall performance of the amplifier? Are we talking about an open-loop signal at the base of Q5? The signal at the collector of Q7?
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I went through my service manuals , 10 amps with a similar CFP differentials
from the 70's. how could you get a patent on what has already been built/sold ?
OS
from the 70's. how could you get a patent on what has already been built/sold ?
OS
You need to go on a jihad against the patent office. You are energetic, enthusiastic, and 100.000% convinced you are right. All of these are powerful weapons when fighting a bureaucracy.
Better question, how are they suppose to enforce it? Pfft. Sure. As most of you have already noted, it's nearly impossible.
Anyone still listening to LP's?
CD players are about to stop.... only one source of mechanism left.
FM about to stop.
That only leaves HD downloads/streaming.
THx-RNMarsh
CD players are about to stop.... only one source of mechanism left.
FM about to stop.
That only leaves HD downloads/streaming.
THx-RNMarsh
Got to laugh, like they need to record rap music in HD audio.
Even Neil Young with all his guitar distortion grunge and off key voice, like he needs HD resolution too. Boy people lose track of what is necessary and what is a waste of time.
Richard, I think the LP will outlast you and me.
Even Neil Young with all his guitar distortion grunge and off key voice, like he needs HD resolution too. Boy people lose track of what is necessary and what is a waste of time.
Richard, I think the LP will outlast you and me.
Real high fidelity is still with us and strong amongst those who care to pursue it. It is just more expensive to get 'right' than it used to be. Quality recordings of unusual merit have been made for the last 60 years or more, if one chooses to seek them out.
Mid-fi has always been with us, especially with the popular music at the time. Today's popular music (rap) is no different than when I first heard Little Richard doing 'Tutti Frutti' at least 60 years ago. It doesn't HAVE to be real hi fi, just playable.
As far as real hi fi software is concerned, it isn't necessarily at the discount store, but it is available by mail order or real hi fi shows. Hi end is alive and well.
Mid-fi has always been with us, especially with the popular music at the time. Today's popular music (rap) is no different than when I first heard Little Richard doing 'Tutti Frutti' at least 60 years ago. It doesn't HAVE to be real hi fi, just playable.
As far as real hi fi software is concerned, it isn't necessarily at the discount store, but it is available by mail order or real hi fi shows. Hi end is alive and well.
Get out from under a rock. LP's sell better than they have in years.
FM isn't stopping is it? I think it's just going digital signal.
Digital is getting better too! Like Richard says. Quality vinyl records are also available. SACD is pretty good, already, for the most part.
I still remember the prophecy from the eaerly 70ies that vacuum tubes will slowly slip into oblivion as transistors get better and better. It sure doesn't look like that came true to me.
On LPs, everybody has their answer to that. I still do listen to them, although I admit they are now my secondary source, right after the CDs. One of the raesons is that I still have material recored on LPs with no CD equivalents, the other reason is pure nostalgia and it makes me fell good to go therough the whole masochistic process of playing LPs and cleaning them.
Year ago I sold off my reel to rell machine, a Philips N4520, all 25 kilos of it, when I finally found a few cassette decks which could produce recording almost of the same audio quality as a reel to reel at 7.5 ips, most notably have high frequency lossess of less than 5 dB re. 1 kHz, just like reel to reel machines used to have. Blank reel tapes are hard to find and are very expensive, while cassette tapes are still available in quantity and quality for reasonable money. Admittedly, this is achieved by using multiple electronic systems, like Dolby C and HX Pro, but I still have dual capstans, quartz lock and MANUAL calibration (Sony TC-K 808 ES) It still alows me to have an all analog signal path right to my ears, as John once said, with all the nice distortions of the tape recording process distortion. 😀
Also, remember that situations vary across the globe. Poorer countries still use lost of FM stations, and some of them are rather good, even if most used MP3 Nonetheless, my Revox B760 tuner still occasionally makes me visually check whether I'm listeting to it or the CD player.
So, why force digital? Let it grow up and fight for its No.1 place. Most Internet radios I've heard are very convenient, but still below par of high quality FM radio waves.
On LPs, everybody has their answer to that. I still do listen to them, although I admit they are now my secondary source, right after the CDs. One of the raesons is that I still have material recored on LPs with no CD equivalents, the other reason is pure nostalgia and it makes me fell good to go therough the whole masochistic process of playing LPs and cleaning them.
Year ago I sold off my reel to rell machine, a Philips N4520, all 25 kilos of it, when I finally found a few cassette decks which could produce recording almost of the same audio quality as a reel to reel at 7.5 ips, most notably have high frequency lossess of less than 5 dB re. 1 kHz, just like reel to reel machines used to have. Blank reel tapes are hard to find and are very expensive, while cassette tapes are still available in quantity and quality for reasonable money. Admittedly, this is achieved by using multiple electronic systems, like Dolby C and HX Pro, but I still have dual capstans, quartz lock and MANUAL calibration (Sony TC-K 808 ES) It still alows me to have an all analog signal path right to my ears, as John once said, with all the nice distortions of the tape recording process distortion. 😀
Also, remember that situations vary across the globe. Poorer countries still use lost of FM stations, and some of them are rather good, even if most used MP3 Nonetheless, my Revox B760 tuner still occasionally makes me visually check whether I'm listeting to it or the CD player.
So, why force digital? Let it grow up and fight for its No.1 place. Most Internet radios I've heard are very convenient, but still below par of high quality FM radio waves.
Whilst the DVD and bluray are still be pumped out in qty there will still be mechanisms that will play CDs.
And yes I still listen to LPs.
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