The only problem with deductible expenses is generating the income from which they may be deducted.
That's where filing jointly is a benefit, one works and one can play. Last time my wife read one of my posts (not here) there was hell to pay. Big
's please.
Good at least you are placing some context around your claim, still dadod disagrees and I think Mr Marsh is strongly behind his work. Respected members here are making both VFA and CFA amps with 60dB of GNFB and are liking the result.
I've been blessed with a lot of my work being indistinguishable from play. As the old adage goes, Love what you do and you'll never work a day in your life.
I recall an exception when things were going particularly badly at Harman, and I was bitching excessively to my immediate boss about leaving the job. He assured me that it could be arranged.
It is amazing that people who do something for a living can have such significant gaps in their knowledge or believe such myths. Before I came on DIYaudio I naively assumed that commercial audio equipment was designed by people who were at least as competent at what they did as I was at what I did for a living. I was genuinely surprised to discover that this is not always the case. More recently I have discovered that radio antenna design can suffer from the same problem.john curl said:
It is easy to understand: some people prefer a little distortion with their music. Unless you disbelieve in electronics there can be no other factors than the difference between what went in at the input and what came out at the output; in fact is is quite silly to suggest otherwise.
I'm not sure whether you speak of non-monotonicity of distortion vs. signal level or audibility vs. distortion level. For the latter there is evidence that for some people the optimum amount of distortion is not zero; they like a little distortion, and find both less or more distortion less pleasant to their ears.Chris Hornbeck said:
Just to add some context: in another thread someone said that he preferred certain polyester capacitors. I said that this could be because of the nonlinearity of polyester. kamis then popped up with a sarcastic comment aimed at me.kamis said:
The attack on boutique components is ironic in view of the steadfast defense of $50 RCA plugs.
In order to incorporate the output filter of class D amps into the feedback loop, ensuring straight FR under different loads. It is an interesting patent.
I think around this level is a practical figure for a discrete power amplifier using readily available components (I am talking linear amplifiers here and not class D).
Sure, if someone has some GHz high power output devices and drivers we can increase it substantially - but those do not exist that would be suitable for driving high powers in linear mode at anything like reasonable cost. But practically its about 35 dB or there about at 20 kHz. Some execeptional designs might get 40 or 50 dB at 20k, but they probably have other problems.
What I love about Bruno's initial invention: it was done to minimize cost, while he was an employee of Philips. I don't know the details of his separation, but I think it should go down in the annals of corporate organization as about the stupidest thing ever, if it was in any way a push rather than a pull.
And why Philips, now NXP, never bothered to integrate the circuit is baffling.
Among other things, it illustrates that people tend to form judgments first, and construct justifications later. Pointing out to people their inconsistencies and other reasons why they might be wrong can have the effect of making them more certain than ever that they were right all along. See the backfire effect: Google
Yes I recall you could use the circuit as long as you used Philips/NXP parts. How they would police things if you didn't is another question.
Because there is no money in high volume audio power IC's. And that's been the case for about 10 or 15 years.
Trust me, most of this stuff is at low double digit Gross Margins margins if you are lucky. There are lots of Chinese, Korean and Taiwanese outfits now making class D amps for TV, boom boxes etc. NXP supplied some of the Japanese for a while but pricing was always ridiculously low and they pulled out in about 2009/2010. You need to be doing 30-40% GM to break even, and really profitable companies like LT and Maxim last time I looked were at 60%+. Philips always aspired to that, but they were a consumer semi company and those kind of margins were just not there. NXP quickly moved the business in the right direction - anything not highly profitable was quickly axed.
The audio business ended up going into mobile phone audio (lower power class D + DSP and a whole bunch of other stuff) where they were very successful very quickly. I've been out of it for a year now so do not know what the situation is - probably lots of competitors have piled in and the margins have been competed away . . . that's semi's for you.
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Yes as I said what can be achieved given a level of technology, just looking for some justification for a universal rule. In the end as much GNFB as technology allows seems to be OK. So if the ultra-high speed devices actually existed 60, 70, or even 80dB would be OK.
Distortion is an effect used in music, as are compression, reverb, passage through magnetic tape, delays, etc. To a good recording engineer, they are as spices are to a master chef.
Nothing wrong with preferring one dish to another. But, it seems like some times people may attribute good sound solely to low distortion. "If it sounds better, it must be lower distortion." Not necessarily so.
Well, if some people like amps with 10dB gain margin why not...
Indeed there was, and still is, a tendency to beliefs that CFAs are immune from such limitations..
I understood that it was to improve something, my question was about the resulting numbers, THD, IMD DF and so on.
What else is new, I don't think the average poster here quite gets how bad it is. For consumer audio the claims of higher performance are mostly a smoke screen and the price of the BOM is all that matters.
Oh yeah has Pono taken over the market yet?
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Thanks to my and others figuring out how to get them to work, the TDA2007A class AB amp from STM was used in the millions and to a fairly good performance level given the insanely low price. I got concerned that the supply might cease and asked a ST person about it. He said Don't worry some idiots are still using it in megaquantities
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