Exactly.
JC's description of how things work at Parasound sounded equally bizarre to me...
Exactly - and so the way they need to be dealt with is different, so the distinction is very important.
Who cares? At 20kHz all we require of an electrolytic is that it has a sufficiently small impedance, we don't care about the angle. Just because we can measure it, it doesn't mean it matters and it doesn't mean we can hear it.RNMarsh said:
"Z is low enough" is all we need.
Tiny effect, can be ignored - almost always. If worried, estimate its magnitude then decide whether to worry or not.
To be slightly more pedantic: Faraday is a name so the unit named after him (farad) uses an initial capital when abbreviated - but not when spelt out. So 0.5 farads is 0.5F. Same rule for amps (Ampere) and volts (Volta).jan.didden said:
Sigh! One produces distortion (new frequency components not present in the input); the other does not - however much some people frighten themselves by looking in the time domain.RNMarsh said:
Same rule for coulombs and joules. I'm sure someone will come up with an exception, but the general rule is that SI units derived from a person's name are spelt in full without an initial capital (because they are not a personal pronoun) but the symbol has an initial capital.
Also henries, hertz, kelvin, watts, ohms (although that gets a Greek O!).
Also henries, hertz, kelvin, watts, ohms (although that gets a Greek O!).
Sorry to inform you the voltage and current in a capacitor are 90 degrees out of phase in SPICE. I mean really, come on.
??? Do-you consider you hifi system as a measurement instrument, or a musical one ?
An amplifier is NOT a device that just amplify the voltage in a linear way. it is a device that drive very nonlinear gears: speakers in a very nonlinear environnement, your listening room.
And all the process to reproduce music in your home, from the choice of the instruments by the musicians, the acoustic of the studio, the choice of the microphones, the way the signals are altered by the sound engineers to make-us believe that musicians are playing in your listening room on your imperfect system: it's more like violin making than pure engineering.
I am sorry to tell this, but you can continue to design your gears looking only at measurement's numbers: you will not produce the best product in this make believe game.
I worked for big companies for consumer products not "shed one man boutique" (and little ones for studio gears).
We rarely spoke about "selling price" with my boss, in the R&D office: you are supposed to know the range of the product you'll have to design and the market prices and attempts. And the selling price is the reserved area of the commercial department
With a little experience, and knowing that it will be some used car dealer discussions, you begin to play a little in a dishonest way: over-sizing some parts to let the room for future compromises with your boss/purchasing department manager ;-)
Of course, at each moment of the design, costs are your concern too. For big series, even the one of a strap.
Sorry, but it reflect exactly my own experience, while in very different countries and different markets.
About servos, I read strange things, here. The big difference with caps, in serial with the signal, is caps are chosen for the way they transmit the useful signal, usually dealing with relatively low load impedance while, in servos, the way they can CUT this signal and very high impedance (Mosfets inputs integrated circuits). In my DIY amp at home, I'm unable to measure a phase shift between 10Hz and 1kHz. I am not able to achieve the same result with serial caps reasonably chosen (quality, price and volume).
Well, yes, with some objection. In case of heavily nonlinear ceramics I would rather say that the Z is to be almost negligible compared to load resistance. Please check my measurement of nonlinear 100nF ceramic capacitor loaded with 24k resistor. Both amplitude response and THD plot are shown. Please see that distortion starts to be negligible more than one order above F(-3dB) frequency, though amplitude response seemed to be perfectly flat.
Attachments
Last edited:
Neither, it's a reproducer. Musical instruments are for studios.
You were either R&D (playing with tech) or product development (cost matters). You cannot wear both hats simultaneously but can migrate around. If R&D are building complete ready to manufacture products the company is not being run correctly IMO. In product development the eye is always on cost and each cent has to be justified somewhere. But I was lucky enough to not be in consumer products which is a huge pain.
You album you are listening to has been mixed with the studio monitoring system as a reference. Not with measuring instruments.
If you want to be as close as possible to how the producers wanted it to sound, you need the same monitoring system. Not a "perfect" one. ;-)
Which, in any case ... does not exist.
I see no compelling argument to make every device in a signal chain imperfect. What imperfection do you choose? It is technically possible today to make most amplifiers in the chain without 50yr. old compromises.
I posted the response of an amplifier that was an effects box, if that's not to your taste do you just pick another one? What everyone involved with a musical production did comes down to (in most cases) two two dimensional signals, voltage vs time. The goal of any system is to present that to your speaker/room setup. Speaker/room combos are so "all over the place" I don't know why we even have these discussions.
Last edited:
Just one thing, Scott. My phone (a VERY industrial device) has a very good audio chain. Low distortion, low noise, good enough bandwidth etc.
Comparing to my hifi system, it sound just... boring, flat, no magic...
While I cannot list anything wrong with him.
50yr. old compromises ? I am not sure that most of the actual HIFI speakers on the market had made such progress during the 40 last years, compared to some good old gears (JBL, Tannoy, Quad etc.) of this "good old time" ;-)
I know only one exception: The JBL M series.
I tend to prefer the records of the holly decade (70-80) to most of the actual musical production. Both on the musical content and the way it sound. Is-it an effect of age ?
Neither. Look up what hi-fi means.Tournesol said:
A hi-fi amplifier is linear; others types of amplifier may not be linear.
Speakers are approximately linear.
Rooms are acoustically very linear, although they contain all sorts of filters and delays.
Why do so many of your comments seem to say the opposite of the truth? Are you very confused, or just being argumentative?
If Z is low enough then it doesn't matter how nonlinear Z is. There is a tradeoff here; a linear Z does not need to be as low as a nonlinear Z. A little common sense will tell people that a few polypropylene caps at home will not magically undo all the alleged humungous damage done to audio by the electrolytics in the studio; Occam's Razor then tells us that the right explanation is that the electrolytics (assuming they were the correct value) do insufficient harm to be worried about. On the contrary, it is those who routinely add bypass caps who may do harm - by adding minor suckouts.
I will assume RNM's confusion about Spice capacitor modelling was a momentary loss of concentration, not another fundamental error from someone who claims vast experience of audio.
In other news, someone on another site is very happy with his new Parasound JC3 jr. At $1500 this is still more than I can afford but is very reasonable compared to a lot out there. His purchase was based on a recommendation from Grado when asked what they would recommend for their best cartridges.
From the happy new owner
So there you go. John and Carl are appreciated in user land, even for the products compromised by low selling cost (I guess even if the blowtorch could be built today would be $15000+). What of course would be interesting (and not possible) would be to compare cost of the actual amplification parts between the JC3+ and JC3jr. The more expensive model has a lot more metalwork and expensive PSU bits in it which one could think account for a lot of the delta.
From the happy new owner
So there you go. John and Carl are appreciated in user land, even for the products compromised by low selling cost (I guess even if the blowtorch could be built today would be $15000+). What of course would be interesting (and not possible) would be to compare cost of the actual amplification parts between the JC3+ and JC3jr. The more expensive model has a lot more metalwork and expensive PSU bits in it which one could think account for a lot of the delta.
- Status
- Not open for further replies.