Great to discuss 5534 . In another thread I was told off for talking about it . To which I said anyone can put in a chip holder and say which op amp is best . Could they design an op amp ? I put out a challenge to design one using lets say BC550/560 . Absolute silence followed . My other challenge was amps that must have 3055's and 5534's in the spirit of the valve guys spud amps . I said with skillful design many so called super amps could be put to shame . I was told 3055 is fit only for the bin . One brave sole said on paper they should reproduce music OK .
One thing I like about the Handbook blameless amp is the simplicity . Although never spoken of in the book I can not help but think the designs should meet Bob Stewart's criteria . That would be although hard to prove too many components is not a great idea . Bob forgive me if I am wrong ? The talk in the 70's he gave was said to me to be " Distortion in audio amplifiers due to loss of information " .
I forgot why I got told off . I gave in the thread an oscilloscope screen grab of a 5534 going unstable and the cure . I showed how a LF351N would solve the problem if being lazy without the cure . I then said no doubt a OPA 604 would sound better if a lazy person , I had used the 604 but didn't say . It seemed the red mist was up and I knew nothing about op amps . Good news is I will write to them everytime I am being lazy and want op amp advice . That will be so that the publicity fits the prejudices and gives me a peaceful life .
I did do a blind test of op amps for a friend who insisted . The argument being a LT op amp would be favoured . MC 33078 was the winner . People could hear the LT to be better . They just thought they couldn't live with it . In the application the low noise of the LT was obvious so not too contentious . In the end a MC33079 was used with the four devices in parallel to make a nice cheap low noise device . The noise was then better and not far behind the LT . Anyone who has not done that do try it . I should say if the LT had been specified from the start more trouble would have been taken . My point was simply dropping in a chip is not good practice . That was proved . It all came about because someone had told the lady she was out of date with what she had . We used the German high end show for our Guinea pigs . 5532 and 33078 are not so different in market slot . 5532 slightly better on current , 33078 on bandwidth . Both cost peanuts .
BTW a friend had various op amps fitted to Hypex Modules . 5534 was preferred . At least he can say he is certain . Another friend who was with SSL says that in the right era as much as 90% of the Audiophiles treasured recordings have 5534's used as his best guess .
One thing I like about the Handbook blameless amp is the simplicity . Although never spoken of in the book I can not help but think the designs should meet Bob Stewart's criteria . That would be although hard to prove too many components is not a great idea . Bob forgive me if I am wrong ? The talk in the 70's he gave was said to me to be " Distortion in audio amplifiers due to loss of information " .
I forgot why I got told off . I gave in the thread an oscilloscope screen grab of a 5534 going unstable and the cure . I showed how a LF351N would solve the problem if being lazy without the cure . I then said no doubt a OPA 604 would sound better if a lazy person , I had used the 604 but didn't say . It seemed the red mist was up and I knew nothing about op amps . Good news is I will write to them everytime I am being lazy and want op amp advice . That will be so that the publicity fits the prejudices and gives me a peaceful life .
I did do a blind test of op amps for a friend who insisted . The argument being a LT op amp would be favoured . MC 33078 was the winner . People could hear the LT to be better . They just thought they couldn't live with it . In the application the low noise of the LT was obvious so not too contentious . In the end a MC33079 was used with the four devices in parallel to make a nice cheap low noise device . The noise was then better and not far behind the LT . Anyone who has not done that do try it . I should say if the LT had been specified from the start more trouble would have been taken . My point was simply dropping in a chip is not good practice . That was proved . It all came about because someone had told the lady she was out of date with what she had . We used the German high end show for our Guinea pigs . 5532 and 33078 are not so different in market slot . 5532 slightly better on current , 33078 on bandwidth . Both cost peanuts .
BTW a friend had various op amps fitted to Hypex Modules . 5534 was preferred . At least he can say he is certain . Another friend who was with SSL says that in the right era as much as 90% of the Audiophiles treasured recordings have 5534's used as his best guess .
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The 5534 far predates 1990. The best story is that Mullard/Philips designed an op-amp around one of Rupert Neve's mixing console requirements. This was at least 1974 or earlier. Signetics sold it as NE5534 by 1975, and Raytheon had the "best" version for audio (I don't remember why but I think it could be sorted for THD to a very good spec).
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Scott I presume you do similar ? Willing to name one ?
I do remember 5534 being reviewed by perhaps Richard Brice when it first appeared . The comment was something he found hard to equal .
This was an op amp idea I took seriously and built . It is to this day the one I use for tests . Roll back to the chapter 10 beginning . 1992 and showing 5534 to be a bench mark by then .
Hickman's Analog and RF Circuits - Ian Hickman - Google Books
I do remember 5534 being reviewed by perhaps Richard Brice when it first appeared . The comment was something he found hard to equal .
This was an op amp idea I took seriously and built . It is to this day the one I use for tests . Roll back to the chapter 10 beginning . 1992 and showing 5534 to be a bench mark by then .
Hickman's Analog and RF Circuits - Ian Hickman - Google Books
The emphasis then was precision imstrumentation, the DC specs on the 5534 are not especially good.
You can outboard a discrete pnp (base to comp pin and emitter to output) on the AD744 and with the external compensation you can make a pretty hot line level amp.
5534 designer and timeline
The mystery continues...confirming your memories...I have a 1995 Philips Semiconductors "General-Purpose/Linear IC's ". It has application note AN142, originally written in October 1984, "Audio Circuits using the NE5532/3/4".
So, Johan's memory of the date is off...I can check with him and see if this jogs his memory on the other point...
The mystery continues...confirming your memories...I have a 1995 Philips Semiconductors "General-Purpose/Linear IC's ". It has application note AN142, originally written in October 1984, "Audio Circuits using the NE5532/3/4".
So, Johan's memory of the date is off...I can check with him and see if this jogs his memory on the other point...
I think the LM118 predates the NE5534, and they're virtually the same topology:
http://www.ti.com/lit/an/snoa850/snoa850.pdf
http://www.ti.com/lit/an/snoa850/snoa850.pdf
Scott . We did that with the horrible 741 and added a current source to the output and negative rail . Transistors would be 2N4403 . I am told some Audiophile recordings were done that way as that was the microphone input of some mixing desks . I am tempted to build it and use the best Neumann we have . Bipolar op amps make doing that simple as the input adopts the new devices and locks the DC conditions . On our side of the pond we call that " making a silk purse out of a sows ear " . Nearly . The expression if it hasn't migrated means it never happens . I never tried a serious op amp with the idea . I have some 2SA970 that might be OK as inputs .
Hi Guys
Nigel, if you want to drive the maggies or any ESL better, you need an amp with a wide safe operating area - ideally wide enough to handle 90-degree currents. All this requires is a large enough output stage to withstand full current at full voltage across the output devices - parallel enough pairs and you are there.
As far as writing style goes, I think it would be impossible to write a book about audio without an opinion. It is human nature to invest yourself in the work and to impart some of yourself into the pages. To not do this would suggest a lack of true interest or passion for the subject. I think it is obvious in Bob's book, Doug's books and my own books that every author is passionate about the subject - which as noted above, makes the text a whole lot easier to absorb and fun to read.
It is obvious in Doug's writings that economy is high on the list of goals - so typically English, but also the result of working a lifetime inside the audio industry. Bob's book seems more generic and almost aimed at tinkerers, no doubt reflecting the broad range of industry work he has been involved with and that for him (it seems to me) audio is more of a hobby. Certainly, audio is about music and music is about emotion, so it is hard to not have subjective opinions even if you say those are all based on objective facts.
The only problem I have with either book is that the authors refuse to recognise that new volumes are entirely justified - not new editions. Doug wrote his articles for Wireless World (which became Electronics World), then packaged them as an audio power amp book, which added more chapters as more articles from WW-EW were incorporated, to the point where some people may have paid for the original articles six times - seven with ADAP6. Talk about squeezing every penny of return out of something? Bose would be envious.
Personally I think the class-D stuff and the simulation models/ how-to-use-sims stuff could easily be separated out to be separate books. These are whole subjects unto themselves and not strictly linear audio. Besides, it's okay to have thinner books as well as thick ones, and you might open whole new markets for yourself.
There seems to be many talented people on this forum. Why aren't they writing books?
Have fun
Kevin O'Connor
Nigel, if you want to drive the maggies or any ESL better, you need an amp with a wide safe operating area - ideally wide enough to handle 90-degree currents. All this requires is a large enough output stage to withstand full current at full voltage across the output devices - parallel enough pairs and you are there.
As far as writing style goes, I think it would be impossible to write a book about audio without an opinion. It is human nature to invest yourself in the work and to impart some of yourself into the pages. To not do this would suggest a lack of true interest or passion for the subject. I think it is obvious in Bob's book, Doug's books and my own books that every author is passionate about the subject - which as noted above, makes the text a whole lot easier to absorb and fun to read.
It is obvious in Doug's writings that economy is high on the list of goals - so typically English, but also the result of working a lifetime inside the audio industry. Bob's book seems more generic and almost aimed at tinkerers, no doubt reflecting the broad range of industry work he has been involved with and that for him (it seems to me) audio is more of a hobby. Certainly, audio is about music and music is about emotion, so it is hard to not have subjective opinions even if you say those are all based on objective facts.
The only problem I have with either book is that the authors refuse to recognise that new volumes are entirely justified - not new editions. Doug wrote his articles for Wireless World (which became Electronics World), then packaged them as an audio power amp book, which added more chapters as more articles from WW-EW were incorporated, to the point where some people may have paid for the original articles six times - seven with ADAP6. Talk about squeezing every penny of return out of something? Bose would be envious.
Personally I think the class-D stuff and the simulation models/ how-to-use-sims stuff could easily be separated out to be separate books. These are whole subjects unto themselves and not strictly linear audio. Besides, it's okay to have thinner books as well as thick ones, and you might open whole new markets for yourself.
There seems to be many talented people on this forum. Why aren't they writing books?
Have fun
Kevin O'Connor
High Kevin ,
Love what you say . Especially about passion . I think to say D S is passionate might have been overlooked by many of us . Exactly right to say it . One only has to look at the machinery on the non hi fi pages . I was especially drawn to one of an air compressor turntable. Sure it was on the Self site ?
My view is start with a blameless amp and decide what you want . Alan Mornington West seems to have done this with the Naim NAP 250 . I said to someone if they don't like the Naim I could change that easily . The amp by just changing the LTP balance would be different . It seems to be adjusted to have Jean Hiraga distortion spectrum . That is second higher than third and so on in suspension bridge curve . Like a Quad 303 .
Interesting what you say about Maggie's . I had assumed that . I get involved with big gradient devices as used in body scanners so have those ideas burnt into my brain . More via friends these days I should say , I stopped building them in 2002 . As I said to someone Maggie's might not be bad with a NAD 3020 . 3020's runs rings around some amplifiers when 2 ohms .
Class D worries me . It seems to me that at best they are very OK . In the PA world they brake fewer backs . The rule of thumb is Class D half the weight of Class G ( or whatever ) and a quarter class AB . Some of that might be less if using switch mode PSU . The crunch is if no better why allow ourselves to make modules into amps we pretend to build . We are not PA people most of us . I call it cake mix amplifiers . All you do is add eggs .
If careful a blameless amp can be made on tag board . I did it once , it worked fine . Granted not ideal . The Gain Clone people should try this .
One thing I think I see with class D is that the big companies want to dominate as they might have done in the past . Although the hobby will never die I don't think anyone out of a false sense of duty should promote class D over AB let alone class A . I feel CD was promoted over LP with hype bordering on lies ( " Perfect sound that lasts forever " ) . Some had to really hold fast to the mast and insist it was dreadful . We were right and CD required improvement . So don't anyone say something is fantastic when what you are saying considering how bad you expected it to be . In all fairness I like what I have heard . I still doubt the extra work it has to do is a virtue ? A blameless amp is blameless and that being so can not be bettered ? If it weighs more or uses more electricity is not exactly about sound .
Blameless to me is lets say -80 db distortion at mostly any volume . I feel that is 20 dB better than we might really need ?
Love what you say . Especially about passion . I think to say D S is passionate might have been overlooked by many of us . Exactly right to say it . One only has to look at the machinery on the non hi fi pages . I was especially drawn to one of an air compressor turntable. Sure it was on the Self site ?
My view is start with a blameless amp and decide what you want . Alan Mornington West seems to have done this with the Naim NAP 250 . I said to someone if they don't like the Naim I could change that easily . The amp by just changing the LTP balance would be different . It seems to be adjusted to have Jean Hiraga distortion spectrum . That is second higher than third and so on in suspension bridge curve . Like a Quad 303 .
Interesting what you say about Maggie's . I had assumed that . I get involved with big gradient devices as used in body scanners so have those ideas burnt into my brain . More via friends these days I should say , I stopped building them in 2002 . As I said to someone Maggie's might not be bad with a NAD 3020 . 3020's runs rings around some amplifiers when 2 ohms .
Class D worries me . It seems to me that at best they are very OK . In the PA world they brake fewer backs . The rule of thumb is Class D half the weight of Class G ( or whatever ) and a quarter class AB . Some of that might be less if using switch mode PSU . The crunch is if no better why allow ourselves to make modules into amps we pretend to build . We are not PA people most of us . I call it cake mix amplifiers . All you do is add eggs .
If careful a blameless amp can be made on tag board . I did it once , it worked fine . Granted not ideal . The Gain Clone people should try this .
One thing I think I see with class D is that the big companies want to dominate as they might have done in the past . Although the hobby will never die I don't think anyone out of a false sense of duty should promote class D over AB let alone class A . I feel CD was promoted over LP with hype bordering on lies ( " Perfect sound that lasts forever " ) . Some had to really hold fast to the mast and insist it was dreadful . We were right and CD required improvement . So don't anyone say something is fantastic when what you are saying considering how bad you expected it to be . In all fairness I like what I have heard . I still doubt the extra work it has to do is a virtue ? A blameless amp is blameless and that being so can not be bettered ? If it weighs more or uses more electricity is not exactly about sound .
Blameless to me is lets say -80 db distortion at mostly any volume . I feel that is 20 dB better than we might really need ?
Just curious, why would be impossible for audio (and in particular power amplifiers), while it is certainly perfectly possible for topics like A/D and D/A conversion, analog and digital filters, analog and digital signal processing, etc... Tons of such reference books in our library, all (one way or another) related to audio reproduction.
Let me guess: because of the target audience, expecting (and enjoying) a certain degree of bias? Nothing wrong with making your target audience happy, of course, while also understanding you can't make everybody happy.
My library has fewer books now . Oxford isn't exactly the last place in the world to cater for an interest in electronics . I will go again and look . I got the first ever copy of this book from there . Section 621 close to Marine Diesels ( see sine wave analysis if you do on Diesels , same as audio , vibration due to clipped wave on compression ) . My German friends were impressed the numbers work in every Library . They thought not so in Germany , I doubt that . I hope I got 621 right as it has been a while . If not an Armstrong amplifier with Darlington VAS .
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Hi Guys
Waly, if you read the next line of mine after what you quoted, the answer is there. Audio is packed with emotion by its nature, as the use of the equipment is supposed to stimulate our senses.
This is not to say that a designer of computer chips is not passionate about his work, and does not write passionately about it.I've talked to those guys and they definitely love their work. There is always satisfaction in creativity and in achieving a goal. Frankly, I've never found a book about any subject that was not filled with the passion of the writer. There are lots of problems with A-D and D-A converters, to use your example, and engineers working to solve those issues do write with the same verve as everyone else when presenting their solution. It may be harder to see in some cases, clouded by high-level math or "scientific form" expected for a thesis paper, professional journal, etc, but you glean it if you as a reader have any passion or empathy at all.
What would be the point of writing a dispassionate discourse? Trying not to offend anyone? Well, that will happen anyway as the readers are not identical and some may 'offend' if their opinion or view has not been spouted. That happens every day even on this forum....
Doug sometimes seems to want to come across as "just analytical" but he betrays himself all the time. His passion comes through, along with his pet peeves and preferences. It rounds out the reading experience and makes his analysis more accessible. He may be arrogant at times but he has the goods to back up his view. I like that and like him and his work all the more for letting his humanity leak out into his writing.
You may think certain things are just "givens", and undeniable as facts. The world was flat until one guy said maybe it is round, then more, and now mostly it is round. Some still say it is flat. It may not exist as we "know it"... But even "facts" are subjective to some people, so you can never make an entirely dispassionate explanation that everyone will abide.
Have fun
Kevin O'Connor
Waly, if you read the next line of mine after what you quoted, the answer is there. Audio is packed with emotion by its nature, as the use of the equipment is supposed to stimulate our senses.
This is not to say that a designer of computer chips is not passionate about his work, and does not write passionately about it.I've talked to those guys and they definitely love their work. There is always satisfaction in creativity and in achieving a goal. Frankly, I've never found a book about any subject that was not filled with the passion of the writer. There are lots of problems with A-D and D-A converters, to use your example, and engineers working to solve those issues do write with the same verve as everyone else when presenting their solution. It may be harder to see in some cases, clouded by high-level math or "scientific form" expected for a thesis paper, professional journal, etc, but you glean it if you as a reader have any passion or empathy at all.
What would be the point of writing a dispassionate discourse? Trying not to offend anyone? Well, that will happen anyway as the readers are not identical and some may 'offend' if their opinion or view has not been spouted. That happens every day even on this forum....
Doug sometimes seems to want to come across as "just analytical" but he betrays himself all the time. His passion comes through, along with his pet peeves and preferences. It rounds out the reading experience and makes his analysis more accessible. He may be arrogant at times but he has the goods to back up his view. I like that and like him and his work all the more for letting his humanity leak out into his writing.
You may think certain things are just "givens", and undeniable as facts. The world was flat until one guy said maybe it is round, then more, and now mostly it is round. Some still say it is flat. It may not exist as we "know it"... But even "facts" are subjective to some people, so you can never make an entirely dispassionate explanation that everyone will abide.
Have fun
Kevin O'Connor
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I imagine that if you looked here in the USA in the library you would find we use the same numbering system. The Dewy Decimal system if I remember correctly. Nice to know that we have much in common rather than so much that isn't. But these days it seems that he libraries think that they only need to have digital copies or you have to call in a book from another branch as so many go to the library just to get online these days........The best place I find is at the local engineering library at UCLA in Los Angeles, they actually still keep copies of old journals such as JAES and others that you won't find in any library.
That cheers me up . I am not Dr Pearson and never was . I used to read in what is now called Oxford Brooks University . The books I read were from the stack . One day after being addressed I admitted I had no right to be there . " Oh that's OK you are ensuring we keep the books " . The best one I read was about using positive feedback in valve amps to reduce distrotion . That was either 3 or 4 valves . The 3 valves had some positive feedback . A greater negaive feedback to compensate . The two amps had the same measurements . It was like a great secret being given to me . Another had heat to record on a plastic tape . Perhaps even now better than most storage mediums . I think it was 50 000 binary hills per inch ? Erase with heat and re-record . A damping factor of 3 being an ideal minimum using a foil switch to determine if damping was working . I also know a lot about diesel engines . I proposed one with diesel lubrication . A total loss two stroke on Dunalt principle ( no contamination of fuel , stepped piston ) . Even using diesel as coolant . The internet is not the same , it does not make you read marine diesels . My engine , no valves , no oil change , no water , preheats the fuel to 90C . 60 MPG ? V4 1000 CC . Supercharged . Pollution to regulations . Intended for hybrids .
To write a really good book, one to be proud of, takes an enormous amount of time and effort. The payoff is not impressive- to get the rich amount of data he presents, the author of one of the most successful books on tube amp design spent more on the supplies and equipment necessary than he ever recovered in royalties.
Thanks, but one would do better writing porn.
You were not "told off", you old scoundrel, you were simply asked why haven't you taken a look at newer op amps which had come along since then.
For example, I mentioned OP 37, OPA 275 and AD829 as three, in my view, op amps well worth looking into. John Curl mentione LF356 and 357 as two older but trustworthy workhorses, still others mentione the Texas Instruments line, the old Burr-Brown OPA6xxx op amps, etc.
I do not recall anyone statint flatly that the NE op amps were no good and should be thrown away, just that at their time of appearance they made quite a splash, and rightly so, that they were still perfectly usable, but that perhaps there had appeared better alternatives.
And, let's be honest about it, personal preferences plays a significant part in the process of selection. I tend to prefer Analog Devices op amps by default simply because at the time I started fooling around with them, AD had what I saw as the best offer around. To this day, I wouldn't be caught dead without a reasonable stock of OPA 37, AD 818, 828 and 829. I certainly do not claim them to be the best ever, I am simply used to them, I feel comfortable with them.
Just as my output devices can be by anybody so long as they are called Motorola/ON Semi.
In over 30 years, NOT ONE such device ever failed me, even when it wasn't the device's fault.- Status
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