I usually use Nippon ChemiCon SMH parts (85°C). No problems with them. Sometimes 105°C (they are bigger), but not always.
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Hi Pavel, yes your result is same as mine. As I said this circuit (current conveyor) distortion and noise is mostly defined with R19 and R1. Lower the resistor value lower the noise, but increase in distortion. This is just quick simulation not finished circuit to show some of it's advantage.
Hi Damir, distortion is very low and keeps low values even for heavier loads, I tried 1k. Regarding stability, there is some peaking about 70MHz inside the structure, but probably not harmful. Did you have a chance to build a functional sample, or are you in a simulation step?
Yes, diameter is important, ie diameter of rubber bung.
A few years back I rebuilt a wall of power amps that had been in continuous operation for 20+ years.
Except for main reservoir 'beer can' caps all caps were same make/model series.
The caps 10mm and less diameter were all bone dry, diameters 12.5mm and above measured fine....I replaced them regardless.
IME the diameter/compliance of the rubber of the bung of electro caps is critical.
Dan.
Would you mind mentioning cap producer company name? At least, if not the type. Without such info, I am skeptical to your observations.
That piece you quoted contradicts itself. It says that DA is nonlinear, then says that it can be modelled with a linear network. Maybe the writer is one of those people who scares himself by looking at the 'nonlinearity' caused by a perfect filter, when seen in the time domain?Max Headroom said:
Time behaviour is rather slow. If we assume normal exponential relaxation of the polarisation (which is what seems to be observed) then this does not explain why some dielectrics appear to sound different from others. As I keep saying, DA may be a marker or proxy for something we can hear but we can't hear DA itself - it is too slow and too linear.
To quote Bob Pease, "Soakage is a fairly linear effect: It's just as hard to charge a capacitor up as it is to charge it down."
Starting on page 69 you will find Samuel Groner's measurements. Note the Vishay MKP 1837, no measurable distortion >-150dB or so.
http://www.nanovolt.ch/resources/low_distortion_oscillators/pdf/low_distortion_oscillator_design.pdf
A line stage that might be discussed in a line level preamplifier thread (though in Lounge).
Ayre Acoustics KX-5 Twenty line preamplifier | Stereophile.com
Ayre Acoustics KX-5 Twenty line preamplifier | Stereophile.com
Smirk as you might be trying to be, you might actually want to do some research on human testing methodologies. Because there's plenty of information about just that out there.
I noticed that Stereophile has reviewed the JC-3jr (well Fremer). Interestingly he really seems to rate products by price tag as his current reference phono stage is $50k and therefore much better than the JC-3 or JC-3jr. Sadly being a Fremer review no measurements. I reckon John needs to come up with a new reference product as the market seems to be happy to support wincingly expensive!
Hey Scott,
I think the Ayre QX preamps use this topology, but not cheaply for sure...
Cheers,
Howie
The amplifiers were BGW, I forget which model, 750?? maybe.
The caps were light blue, I did not take note of manufacturer, perhaps somebody here knows what BGW used at the time.
This situation is not unique to BGW, small diameter electros are always the first to suspect in all gear, particularly those near to regulators.
Dan.
Bill,
The Contstellation Orion phono stage is John’s best commercially avaiable phono stage (on a very limited) basis for reasons of device availability (and selling price of about $70k was the last I heard)
But I believe John likes the Blowtorch phono stage even more, but
It is even harder to find appropropriate idss NOS Toshiba input devices for.
The Contstellation Orion phono stage is John’s best commercially avaiable phono stage (on a very limited) basis for reasons of device availability (and selling price of about $70k was the last I heard)
But I believe John likes the Blowtorch phono stage even more, but
It is even harder to find appropropriate idss NOS Toshiba input devices for.
Yes, the noise performance of this preamp is not perfect, to stay politically correct.
Do not you also think that higher noise level might be, in fact, preferred by many listeners? (Though unintentionally). Do I need to explain why?
Ah yes had forgotten the Orion. Although with that, what was wrong with John's line stage designs that they needed someone else for that?
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