In the immortal lyrics of Bachman-Turner Overdrive hit, "You Ain't Seen Nothin' Yet".
Consider.
Transistors basically act as modulators. Therefore, you need at least two resistors per trannie to get it where you want it to be, in the operating mode you want it in.
What you see on the photo is all right for what that amp was, but it isn't much compared to what later series FP amps used. Their input stage alone used 118 transistors, which implies roughly 236 resistors, or 472 resistors for a stereo version.
I wouldn't be surprised of the complete amp had anything between 800 and 1,000 resistors overall. What would that be, a resistor Xmas?
Consider.
Transistors basically act as modulators. Therefore, you need at least two resistors per trannie to get it where you want it to be, in the operating mode you want it in.
What you see on the photo is all right for what that amp was, but it isn't much compared to what later series FP amps used. Their input stage alone used 118 transistors, which implies roughly 236 resistors, or 472 resistors for a stereo version.
I wouldn't be surprised of the complete amp had anything between 800 and 1,000 resistors overall. What would that be, a resistor Xmas?
I built a power supply this week with what I have available . BD135 and 136 . The results are about 10 dB better than a LM317 or 337 . Simple zener diode chain and capacitor filters . Voltages near enough perfect . Cheap low noise devices with good bandwidth . These ones have surprising high gain ( 200 ) . Surely much more than resistors we should worry about active devices . I can hear resistors . Carbon comp does sound 1950's ish . Surprisingly is hardly shows on measurements . I say that because CC is a NO-NO device in text books . It's low inductance is handy as is price . Zener diodes are NO-NO also , I was told that 40 years ago . Only recently did I check and found zeners are better than commercial regulators if used with care . The band gap reference I was told to use isn't as good on noise . The best noise 317 can give is about 17 bit . Transistors and zeners about 20 bit . John a friend says do not think 24 bit DACs and 17 Bit PSU a bad idea . It might be helpful . Now that needs saying .
In my work I use LM317's . It is that I can dial an exact voltage and it is good enough for my needs , 1.5A is useful . A zener would be hopeless . Audio has no need for this usually .
In my work I use LM317's . It is that I can dial an exact voltage and it is good enough for my needs , 1.5A is useful . A zener would be hopeless . Audio has no need for this usually .
It seems wire-wound in inductive anti phase is the best value . Foil resistors loading MC pick up's do seems better . I have used metal film in inductive anti-phase ( two ty-rapped from the same batch , colours opposite ) . It might be imagination , I felt it worked better and is so cheap . CC sounded better than single metal film although a bit dull . This was pick up loading alone . No difference higher up the circuit . The single metal film makes the stylus sound as if it is dirty . A friend sent me a bunch of Tyco resistors to fit to his preamp . I was to say the least surprised . he paid $8 for each , $20 if Farnell . The sound difference greater than between the NE 5534 and anything that can be bought . Measurements were not showing much . The nearest is swapping tubes in amps . Like between Chinese ECC 83 and Brimar or whatever . The Chinese ( white box ) one sounds metallic and the Brimar lush . Both measure about the same .
Do not mention Vishay to me. Many years ago, I wrote a white paper for John Cunningham of Texas Components, maker of Vishay resistors. I was attempting to explain why they made even digital circuits"sound better" Low and behold, John sent a copy to Vishay Corporate. The very next month there is an ad in TAS, citing the points I had made with NO ATTRIBUTION. They are a bunch of intellectual crooks. Regards John Dozier
I think there is merit in considering resistors . Some rod shaped Philips ( BC ) in the largest SMD seemed the best value that I found . Getting rid of one wire seems a good idea . The ones in question were recommended for low noise applications . I found them especially easy to solder compared with most SMD . 50 = $1 typical . Although disapproved of I used a magnet to hold them ( yes copper on steel tinned end caps ) . Then solder a temporary wire to place them . Solder and remove wire in on go . Many resistors have steel wires . I doubt it is a problem . I have some Soviet resistors with silver wires . They were the best I suspect . As far as I know pure silver and < 1% .
The kind I hate most, the smooth slickers, pretending to be something, when in fact they are little removed from nothing.
I've also been ripped off a few times, half my text quoted with no reference to me, published as their text.
Neither - a good circuit instead.
Although, truth be told, I am partial to silver wiring, either fully pure silver, or well made OFC copper which is silver plated.
Also, pay attention to the soldering wire. Most contain silver these days, but the perecntage of silver in them varies, at least in Europe, from 4 to 9 per cent. I am currently using a British solder wire because it has 9% of silver inside, while my 30+ year old acquaintance, Flutin of Germany, seems to have stopped at 7% (as far as I can tell).
All I know is the leads were pure silver ( my brother analyzed them ) . And why not . Silver was the waste product of other mining in those days . Not very expensive . Now is different . Also the Soviets often were very exacting about details .
I made a universal phono preamp for an ex Decca recording engineer using those resistors and polystyrene caps . It worked a bit like a safe combination . By dialing up certain numbers almost any EQ could be had whilst the signal path remained very simple . Colin worked at Parlophone in the glory days . He said some EQ 's were not official and like a picture coming into focus he could find them by ear . The sound of this EQ box was very open without edginess . Regardless of op amp used I doubt many would hear it's equal . I built half of it on holiday in Penzance about 1 mile from where Michael Faraday started his experiments ( tag boards with resistors and caps ) . Always thought it helped where it was conceived .
Dan you are probably right . One has to guess so much of this . I have tried inductive cancellation of cheap resistors and feel it does work . Two resistors rather than one . This came from a radio amateurs book rather than hi fi .
The reverse of usual beliefs is the steel wires used on some resistors . As far as I can tell it does not make them lower grade .
Similar to this is the use of a capacitor in the feedback arm to an op amp . Even a cheap cap seems better than no cap . Measurements showed nothing of note . My brother said op amps like 100% DC feedback ideally and explains what I heard . This might help explain why some people prefer JFET op amps as they need little or no current to work when in this arrangement . DC offset often is perfectly acceptable without a capacitor so that is not the reason . I also can see that a wire link has the best bass response . The sound often is harsher without a cap .
The reverse of usual beliefs is the steel wires used on some resistors . As far as I can tell it does not make them lower grade .
Similar to this is the use of a capacitor in the feedback arm to an op amp . Even a cheap cap seems better than no cap . Measurements showed nothing of note . My brother said op amps like 100% DC feedback ideally and explains what I heard . This might help explain why some people prefer JFET op amps as they need little or no current to work when in this arrangement . DC offset often is perfectly acceptable without a capacitor so that is not the reason . I also can see that a wire link has the best bass response . The sound often is harsher without a cap .
I recall SY showed a reference measurement resistor assembly that exhibited close to zero series inductance.
IIRC, the construction was a good handful of resistors in in a series/parallel arrangement between two plates that utilised direction of currents cancellation to achieve the low series inductance...no mention of parasitic capacitance though I think.
Stuart, can you refresh some details please ?.
IME, the NF shunt capacitance is of high sonic importance.
Bypassing the typical electrolytic with lower values of solid/film caps increases level and clarity of HF audio reproduction....to be expected of course.
Dan.
IIRC, the construction was a good handful of resistors in in a series/parallel arrangement between two plates that utilised direction of currents cancellation to achieve the low series inductance...no mention of parasitic capacitance though I think.
Stuart, can you refresh some details please ?.
IME, the NF shunt capacitance is of high sonic importance.
Bypassing the typical electrolytic with lower values of solid/film caps increases level and clarity of HF audio reproduction....to be expected of course.
Dan.
I believe it was jneutron's design. Try here - http://www.diyaudio.com/forums/part...sistors-reduce-inductance-but.html#post984766
Don't overlook carbon composition . Sometimes the noise penalty is less than thought . Possibly because the modern versions are better ? They are used for pulse lasers if wondering ( also TV CRT in the recent past ) . Because they have no spiral they seem to stand the pulses better . The discharge times for the laser circuits can be pico seconds ( or less ) . The way pulse lasers work is in discharge as the fastest FET is too slow for what they are used for ( nano seconds ) .
One use of CC is MC pickup loading . I have graphs that show when shunted by the MC typical 7 R the noise is in fact lower with CC compared with metal film . CC sound to my ears is slightly pink yet very open . As if using a tape deck monitor loop . Metal foil ( Tyco ) seem better ( superb and horribly expensive ) . Inductively anti-phased metal film seem almost as good considering the price and rather better than one device . Could be pure imagination . For the cheapest version I don't really mind if it is . I haven't tried carbon film in anti phase , I have a hunch it would be OK .
One use of CC is MC pickup loading . I have graphs that show when shunted by the MC typical 7 R the noise is in fact lower with CC compared with metal film . CC sound to my ears is slightly pink yet very open . As if using a tape deck monitor loop . Metal foil ( Tyco ) seem better ( superb and horribly expensive ) . Inductively anti-phased metal film seem almost as good considering the price and rather better than one device . Could be pure imagination . For the cheapest version I don't really mind if it is . I haven't tried carbon film in anti phase , I have a hunch it would be OK .
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