Most manufacturers didn't bother putting reverse recovery specifications in the databooks for the bridges. The two diode manu's I worked for generally used diodes with TRR's less than 2 uSec, which was generally the slowest diodes we had.
One company I worked at did do custom work, so I could actually make bridges which used 25 nSec and faster diodes, but there the primary concern would be the proximity of the aluminum case. At higher frequencies in a 15 or 25 ampere bridge, the case would begin to dissipate.
I learned it from the guys who twisted the wires for the Lunar Module. They had a hallway that was 1/4 mile long.
Unfortunately, that assertion was not supported by any test measurements which were repeatable by others.
However, the insulation can develop cracking long term because of tension on the outer surface of the wires..over time, that can be a failure mode.
jn
I was also disappointed with copper foil inductors . . . until they had fully run in.
At first they sounded slow and bland but after several weeks they really began to sing - they were made by Mundorf.
Scott would you say that the interconnect has more to do with quality if insulation, quality of connector attachment and impedance of it over a usable range is the real factor that effect its ability to be a transmission line for low level signals. It may be a salesman look at the tree bark and miss the large cat circling around behind you kind of thing .
In this case I am just talking about the resistance and what comprises it, from these effects some excess noise at extremely low levels, maybe, THD at any level, don't see it. By extremely low levels I mean the net contribution, excess noise itself goes down very rapidly with excitation so at very low currents there would in fact be even less of an effect, the opposite of what was proposed.
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See that where I was a bit miss lead . I misunderstood . I have viewed resistance as a dc only thing and impedance as an AC thing . I do not have the test equipment need to look at very low current and voltage that small . I must them rely on your vastly superior ability to collect data. At some point this is a bit humorous when the goal is to fool the brain in to believing that two speakers generate a " sound stage " with width. depth, and height after all. Regards
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Never undersell your own capabilities. This stuff often yields to good sound cards and a little smarts.
In one sense, what is disappointing is that there is not more discussion, evaluation of precisely what contributes to 'two speakers generate a " sound stage " with width. depth, and height', and what doesn't. The micro analysis in this thread at times is excellent for optimising some areas - but are those areas particularly relevant, to good sounding audio? In my own experiments, having aspects that people agonise over endlessly, in threads like this, as sloppy as anything, not bothered with, does not significantly detract from the ability of the system to generate convincing sound - yet other areas where many people's eyes glaze over when they're mentioned I find absolutely crucial.
In the twisting of wires, if each connector of the pair is twisted in such a manner to mimic physically the equivalent of regularly bending the wire along its length, in the same way as the wire is bent to make normal connections - is there still a possible problem in the twisting?
Thanks for the vote of confidence . Off the record you know that behavior is frond upon in this thread. What sound cards do you suggest ? 😱
Agreed as a side note I wound some chokes for an amp with toroid cores and measured 2 times the inductance winding clockwise around the core and clockwise in progression around the core then to anti clockwise and clockwise around the core . So which way you twist the wire may depend on which side of the equator your on much like the rotation of water in the toilet ( as we say here).
P.S I do have a dout of cat thou .
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The tone of this paper is one of over-hype to me. Its hardly 'new technology' to have a keep out area around a gap in a cored inductor. Charles Sullivan has been quantifying and modelling how to optimize this - that work is new and valuable but the basic idea isn't new.
> water in the toilet
Coriolous effect was my original above/below equator
teaching ..........
Somebody needs to do a utube of their toilet
(or at least sink) doing every drain the same direction
for 10 times
(my drains once in a while 'jump the equator')
Coriolous effect was my original above/below equator
teaching ..........
Somebody needs to do a utube of their toilet
(or at least sink) doing every drain the same direction
for 10 times
(my drains once in a while 'jump the equator')
What did they change into as the "ran in"? Were there any measurable differences? The differences I measured in Litz vs. foil were large and in the paper you can see some of the effects in the difference in HF resistive losses in the plots. These are first order effects that will impact crossover frequency and frequency response.
In reading the wc paper, it shows about what I got -- a small improvement at high freqs. I concluded it would be useful for tweeters, at the time. But not worth the size, cost and effort for such a small effect (less than 10%)... I was just looking at Z (mag/phase) and comparing to more traditional coils and inductors. At lower freqs there was no difference. So, I didnt use them. I still have a couple of them in a parts bin.
THx-RNMarsh
THx-RNMarsh
A very, very rough rule of thumb I use is that unless something gives me at least of the order of 10x improvement, somewhere, I don't really see the point ...
I was doing fairy simple but reasonably consistent testing of passive components, driver impedance vs frequency and acoustic frequency response throughout most of the development of the crossover design ( two way, third order, bessel, with driver impedance correction ). However, at the end, having carefully measured my existing laminate cored inductors I sourced and bought air cored foil substitutes, checked their values when they arrived and swapped them in. Have not checked objective measurements since then. ( it's is on my list of things to do )
So assessment was subjective - to me they sounded overly smooth & bland at first but ended up sounding nicely detailed and crisper.
Thx for the info on litz versions I'll check them out if and when I build speakers again.
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On my experience, *good* SMPS sound a lot better than their linear equivalent. L.C. made some listening comparison with his First One between several SMPS and his linear. With the same conclusion. He reported the best one was an unregulated SMPS.
I tend to prefer one P.S. for both channels, for better image stability. He prefered separated ones.
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