I asked a colleague of mine, a professional electronic designer, as well as a professional audio recordist, about the THAT1510-12. The answer was that it is very good, BUT not great. Better can be done with tubes or discrete. Good enough for portable, battery powered stuff. Doesn't surprise me in the least.
Some of this might still apply . Hope it helps .
5.1Precision BJT matched-pairs for Current Sources & Voltage Refrences
5.1Precision BJT matched-pairs for Current Sources & Voltage Refrences
A shame , My first experience listening to mastertapes in an Hi-Fi setting was at Peter Mcgrath's ,(78 or 79) funny seeing it being revitalized again today .
Old time sumting come back again ...
Kid all you want to, Godfrey, but whoever tries them, DOES remember them for a long, long time.
They are NOTHING like the stuff from Heinz cans. No less than 3 types of meat in them, of which two must be smoked beforehand. Lots of carrot, onions and some paprika (not hot). No less than 6 hours on the stove, as slow as you can manage it.
Way back, while we were (dad, mom and I) in Ankara, our best "customers" were the Brits, winning hands down, and followed by the Americans. Both are grossly misrepresented, in my view. The Brits are the next best thing after ideal guests - exceptionally tolerant, they take their time about it, they don't stuff themselves. Americans, as opposed to the idiot stereotype, may not have much of a cuisine (also untrue, but that's another story), but they sure as hell know to recognize good food when they are served some. And unlike many others, they are always willing to try something new, with extremely few exceptions.
Of course, after one of mom's lunches or dinners, everybody knew the Brits wouldn't be coming to work the next day, too preoccupied with ice on the forehead and Alka Seltzer in their tummies, but, to their credit, they NEVER failed to turn up again.
Americans seem made of sturdier stuff, they could take it without casualties.
Which makes both a host's Dream Team guests.
Germans and Austrians not counted, they are practically locals, they can take anything in their stride. And what with the number of Serbian restaurants in both countries, chances are they are already well versed.
Sounds like you had your fair share of Bully Beef ...
Why my IC150A sounded Live ...
Worth trying .
Try BCV 61 and 62 as current mirror in Self type amp ( protected by VAS so 30 V OK ) . Better than transistors I have hand matched ( good Vce ) . Very good if VAS Vbe is < 0.6 V . I use 22R as a starting point for re ( x 2 )
http://www.farnell.com/datasheets/775182.pdf
Worth trying with That's matched pairs . BTW Self amps do not work exactly as simulation . Current mirrors especailly . I add 4R7 to VAS emitter to help that ( not local feedback , a little gain lost ) . Also although I do not know where someone says the input stage noise is not optimum due to resistor values choosen in the same designs .
Try BCV 61 and 62 as current mirror in Self type amp ( protected by VAS so 30 V OK ) . Better than transistors I have hand matched ( good Vce ) . Very good if VAS Vbe is < 0.6 V . I use 22R as a starting point for re ( x 2 )
http://www.farnell.com/datasheets/775182.pdf
Worth trying with That's matched pairs . BTW Self amps do not work exactly as simulation . Current mirrors especailly . I add 4R7 to VAS emitter to help that ( not local feedback , a little gain lost ) . Also although I do not know where someone says the input stage noise is not optimum due to resistor values choosen in the same designs .
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Especially for D V V .
Extreme Low Noise Preampifier
This theme was covered by the predecessor of the That's chip .
This man compares a blameless amp with a previous Naim amp . Interesting reading . Not what I expected . Musicality and sweat !
http://www.pinkfishmedia.net/forum/archive/index.php/t-37966.html
Extreme Low Noise Preampifier
This theme was covered by the predecessor of the That's chip .
This man compares a blameless amp with a previous Naim amp . Interesting reading . Not what I expected . Musicality and sweat !
http://www.pinkfishmedia.net/forum/archive/index.php/t-37966.html
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Interesting interview on U-boob with Mark discussing his early years and that Pre-amp ...
another : http://www.youtube.com/watch?v=sKtPmthrdYw
...
another : http://www.youtube.com/watch?v=sKtPmthrdYw
...
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I didn't John . I heard some Red Rose speakers once and liked them . That was Mark I beleive ?
D V V and I like BF transistors and this seems another endorsement . Seems that performance was out there .
I was told a special Philips TV driver transistor had the best ever Rbb noise ( we called it that , no idea if it's correct ) . Philips required the TV chassis numbers before supplying as they were fed up with us lot buying them ( no idea which ) . TO126 I think .
I learnt about noise from the mic chip we have been discussing . It was the RS spec sheet ( before That's about 10 years ago ) .
Lehmann of Black Cube told me it is the Re if the internal LTP that adjusts gain on the differential input pair on those chips . Johnathan Carr says not .
I added some 2N4403 to an op amp . Lower noise and easy biasing as it was a bipolar input . However the sound was less detailed .
BTW it was Julian Vereker who taught me about noise in about 1976 . His pre amps were not good in that and it did concern him . Not bad for a mechanical engineer JV .
D V V and I like BF transistors and this seems another endorsement . Seems that performance was out there .
I was told a special Philips TV driver transistor had the best ever Rbb noise ( we called it that , no idea if it's correct ) . Philips required the TV chassis numbers before supplying as they were fed up with us lot buying them ( no idea which ) . TO126 I think .
I learnt about noise from the mic chip we have been discussing . It was the RS spec sheet ( before That's about 10 years ago ) .
Lehmann of Black Cube told me it is the Re if the internal LTP that adjusts gain on the differential input pair on those chips . Johnathan Carr says not .
I added some 2N4403 to an op amp . Lower noise and easy biasing as it was a bipolar input . However the sound was less detailed .
BTW it was Julian Vereker who taught me about noise in about 1976 . His pre amps were not good in that and it did concern him . Not bad for a mechanical engineer JV .
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Mark did an interesting interview, but he did not mention me or the products that I designed for him. He is the 'same old Mark', a little more humble than he was for a number of years, and actually quite likable again. He used to be like that when I first worked with him, but he changed a lot as his company powered up. Now he is back to normal.
Nigel, the problem is that we are discussing 'throwaway' designs, rather than anything with some sophistication.
I have been using the 2N4403 in circuit designs since 1968, or 44 years ago, and it is a bit behind the times, except for 'throwaway' designs. Today, we would use a low noise jfet for the input or a device with an even lower rbb'. We would try to make everything direct coupled, and get rid of input and output caps, etc, etc.
I might be wasting your time, here, but wouldn't you rather discuss more sophisticated circuits?
I have been using the 2N4403 in circuit designs since 1968, or 44 years ago, and it is a bit behind the times, except for 'throwaway' designs. Today, we would use a low noise jfet for the input or a device with an even lower rbb'. We would try to make everything direct coupled, and get rid of input and output caps, etc, etc.
I might be wasting your time, here, but wouldn't you rather discuss more sophisticated circuits?
...
Sounds like you had your fair share of Bully Beef ...
Ahem, ... what's "Bully Beef"?
Why my IC150A sounded Live ...
Because you are hard of hearing?
Haleluyah!
That's exactly what I've been trying to get Nige to do. I have absolutely no doubt in my mind he can do it, but for some reason, he seems to be stuck in a time prior to 1978 or so ...
You know, one bipolar and two MOSFETs for a power amp, that sort of thing. While this can work indeed, it will soon show up some of its shortcomings. Nige is an ardent believer in the KISS (Keep It Simple, Stupid!) principle, but takes it too literally. He thinks this means as few parts as possible, whereas I take it to mean as few parts as possible to satisfy the design principles and criteria.
But, given time, ...
In that interview he did not , there was another , actually better interview , where he discussed his early amp/pre , how he sold stuff to the Hollywood elites but for some reason I cannot find it anymore , searched all over so they may have removed it ..
The yanks said that about Russian rockets and aircraft . I work with Soviets and they are very smart . They never throw anything away . When I said 2N4403 I was being provocative . " Yanks " is affectionate I must tell you .
Tin corned beef ......
SHUT THE FRONT DOOR!!!
Wayne, I don't do canned, I don't have to so I don't. I use fresh stuff only. And it's not beef, it's pork.
I am extremely fortunate in the supply aspect of the location I live in. I have both general strores, one supermarket (really BIG), specialized stores (like dairy and general milk products, butscher, three bakers) and amenities (like three banks, one post office, dry cleaning) ALL no further than 150 yards from my apartment building.
That's not counting the contents of the shopping mall right across the street from me, 50 yards distance at best.
Haleluyah!
That's exactly what I've been trying to get Nige to do. I have absolutely no doubt in my mind he can do it, but for some reason, he seems to be stuck in a time prior to 1978 or so ...
You know, one bipolar and two MOSFETs for a power amp, that sort of thing. While this can work indeed, it will soon show up some of its shortcomings. Nige is an ardent believer in the KISS (Keep It Simple, Stupid!) principle, but takes it too literally. He thinks this means as few parts as possible, whereas I take it to mean as few parts as possible to satisfy the design principles and criteria.
But, given time, ...
Better men have tried and failed .KISS in my religion . I have friends who do complicated for me .
My project at this moment is one FET and one 211 tube . At 1000V we go to Gu70 Russian tube ( old German tube ) . No caps from in to out . No feedback globally . Just a bit of fun . Like Ongako only better . Doubt it will work . Uses 1938 anode to drain feedback .
1936 to be accurate as where I am fixed .
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Well, yes, generally true.
I do say "generally" because I have only three types I use alot, and there wuld be the small signal BF 422/423, BF 471/472 and BF 720/721.
This last one, BF 720/721 (300V) or 722/723 (250V), is a particular favorite of mine, because it's one of the least distorting devices I know of.
All three types od devices do share common traits, like a very low output capacitanje (< 3 pF for 422/423), high voltage, not great but very linear gain curve, and not very high but again very linear repsonse (422/423 to 100 MHz).
Also, they are widely available (except for 720/721, not quite anywhere, bit no great trouble either) and very reasonably priced.
God is, I am told, understanding, so in religion, you can stretch the rules a bit.
But to you, KISS is an obsession, and that's a whole new ball game.
Not to worry, mate, it's not a terminal disease, cure does exist.
D V V . You need someone like me around . I just like music and don't get too bothered . Input noise is my obsession . When I add bits I see noise grow . Others do it better that's for sure .
When I see computers there is no work for me in a world like that . You know I even champion new vinyl 78's as the closest approach to the master tape . Remember knowing Michael Gerzon he and I would not be able to agree about that . That's why he took time with me . I was wrong and he was kind enough to teach me .
When I see computers there is no work for me in a world like that . You know I even champion new vinyl 78's as the closest approach to the master tape . Remember knowing Michael Gerzon he and I would not be able to agree about that . That's why he took time with me . I was wrong and he was kind enough to teach me .
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