Hmmm ... what they have is HSPICE, which is YAS, Yet Another Spice, does all the standard things. Had a look at the features brochure, no surprises there. no extra layers of cleverness - there is nothing that LTspice, for example, couldn't do after a bit of playing around ...For example of the full capabilities of SIM software - the size, scope and range... just click on Wiki for Synopsys Inc. ($1.5B/year in sales).
Other popular software is from Cadence-OrCAD. Eagle. And, several others.
Frank
Hello FAS42,
For free sotwareware LTSPICE software it is excellent, but where the good professional stuff gets ahead is that it can accept any level semiconductor models, and the simulator has less converge issues on vary complex circuits, meaning it gets to the end of the simulation without failing to finish your requested task.
For most things on this site LTSPICE will work.
For free sotwareware LTSPICE software it is excellent, but where the good professional stuff gets ahead is that it can accept any level semiconductor models, and the simulator has less converge issues on vary complex circuits, meaning it gets to the end of the simulation without failing to finish your requested task.
For most things on this site LTSPICE will work.
For example the schematics for Parasound JC-2, and Parasound JC-3 are on this website, and the Levinson JC-2 and JC-3 power amp are here as well. Build those with my blessing.
Does anyone has links to those schematics ? I tried to find the Parasound JC-3 on this site but no luck so far.
Hi gpapag, sy, all
When you move from circuits to acoustics, you enter a new domain where “it depends”.
On the other hand, that mechanical gain is still present…
…
In a room, you usually have a mixture of minimum and non minimum phase conditions.
Best
Tom Danley
Thank you Mr. Danley. Valuable contribution.
For a little more elaboration on SY’s, Mr. Gegges and Mr. Danley’s drive lines, page 50 up to 64 of this:
http://www.hometheatershack.com/roomeq/REWV5_help.pdf
For a bit more on the important effect of constant phase shift that listening or measuring distance imposes upon the audio spectrum, see here:
Home - Br?el & Kj?r Sound & Vibration
Fig. 2 is very illustrative (actually, constant phase shift is responsible for altering the timbre of acoustical instruments attack with distance a lot more than h.f. absorption).
George
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We can't avoid resonances, but we can damp them mechanically
I agree.
Mechanical and acoustical problems better to be dealth at their spatial environment by mechanical or acoustical means.
then clean the rest by EQ
I disagree.
Per the above relevant posts, chances are this cleaning action (electrical EQ) will add some smelly mud.
I would leave them alone (as I do with the dirt in my lab)
The question is, "In which place to assume the waist", the problem is quite fatty
I am not sure if this is what you mean, but see attached pic.
I don’t face a problem with this, and where is the fat?
George
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I understand where you are coming from. When I said material properties were not responsible, I meant (even if not clearly stating) things such as grain boundaries, oxygen content, things typically attributed as game changers. For material properties such as conductivity, permeability, permittivity, we certainly agree.Yes, continue here. You said:
And the first part I agree with. Ground loop path variations will effect the system to some degree, and may subjectively alter the sound quality. I have gone through many iterations of dealing with such matters, can't say I always have a firm handle on what works and what doesn't, but understand the potential impact.
However, what I was responding to was your stating that the change wasn't due to material properties. I have done tweaking for many years where the electrical layout has not changed in the conventional sense, including loop pickup and have still seen the effects. In one sense anytime anything is moved, even at the most minute level, loop pickup will alter but the difference between a good vs. a less good arrangement is too dramatic for changes in flux to be the cause in what I've experienced.
Frank
A good example would be IC's. For the exact same geometry, a foamed dielectric running a permittivity of 1.05 vs a solid teflon running about 3, the characteristic impedance of the cable changes by a factor of 1/sqr(delta), roughly 1/1.7 or 60%. This material change will indeed modify the break frequency where return currents would start to concentrate in the source IC vs 50/50 shield path sharing. This alters the loop induction topology, frequency response, and external noise pickup sensitivity. Should the amp not have a well designed rail or primary supply topology (wire layout), this can alter the transfer function as a result of internal coupling.
Another example would be the permeability of the chassis, where ground loop current path would constrict earlier due to path reactance changes.
I meant it well. I respect this man.
When he was theorizing the capacitor as a transmission line, he already had some real life indications while with Motorola. Later it seems he had some proof with the fabrication of high speed digital stuff.
And then it was you with that post 🙂
George
Fair nuff. He did do some good work. The hexfet topology used by IR and IXYS relies on a honeycomb polysilicon (not alminum nor copper) gate mesh structure to transfer the gate voltage across the chip. Because these power devices are actually hundreds of thousands of individual mosfet devices in massive parallelism, if some of them are turned on very quickly such that they try to support the full load current, they will blow. This also happens during turnoff.
I ran micro-cap 4 for a while, was not impressed by it's transient response capabilities. There is a good chance however, that the "driving" issues were being caused by the nut holding the steering wheel..😉
jn
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Version 4 must be at least 10 years old?
At least.
I did not say I was young..🙁
jn
Is it me, or there are some posts wiped off during the last 24 hours?
I remember I’ve read kgrlee intent to comment on minimum phase but I can’t find that post today.
This too is copied and pasted!
George
I remember I’ve read kgrlee intent to comment on minimum phase but I can’t find that post today.
…a foamed dielectric running a permittivity of 1.05 vs a solid teflon running about 3, the characteristic impedance of the cable changes by a factor of 1/sqr(delta), roughly 1/1.7 or 60.
jn
This too is copied and pasted!
George
Is it me, or there are some posts wiped off during the last 24 hours?
It's you. Nothing from Mr. Lee has been pulled out of here recently. One comment from someone else, not technical.
It's you.
The original me.
I was in need of a cofee. Then I found it (post 29622).
Good to know that all runs smoothly
George
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I regurarly use sim software for checking digital layouts, this uses the physical layout (tracking, power planes, pre-preg and laminate thickness Er etc) in conjunction with IBIS files for the active devices to give drive strengths, lead frame parasitics etc. The engineers I work with us various spice software for the analogue side, but as far as I knew spice does not take into account the PCB layout. Do the programs mentioned do analogue and take into account PCB parasitics. The SIV (signal integrity verify, Cadstar)for digital uses transmission line calcs and 3D field solvers, do these work for analogue? or audio frequency range audio, I was under the impression that TL calcs dont?
For audio I keep MicroCap up to date. On Ver 10 now. It is more than sufficient for analog at low freq (Maybe up to 100K-1Mhz) and still be reasonably accurate to the finished product. It cost a few thousand dollars.
Synopsys has many modules that would work with Spice to make it complete for your needs. each company they bought had some aspect needed beyond Spice to make sure you get an exact and accurate finished product. They handle the whole spectrum into IC development and advanced mixed-signal development. Its a lot more than you see on the web site. You have to look deeper to get more. But for simple audio circuits to see if they work and basic parameters, it can work Ok ... IF you can get reasonably accurate device models you can trust.
The original question was - does the simple software SIM show oscillations/unstability. I say it probably does not reliably do so because of the less sophisication of just a basic circuit analysis gives. You either have to learn/know the art or use more sophisicated software.
Synopsys has many modules that would work with Spice to make it complete for your needs. each company they bought had some aspect needed beyond Spice to make sure you get an exact and accurate finished product. They handle the whole spectrum into IC development and advanced mixed-signal development. Its a lot more than you see on the web site. You have to look deeper to get more. But for simple audio circuits to see if they work and basic parameters, it can work Ok ... IF you can get reasonably accurate device models you can trust.
The original question was - does the simple software SIM show oscillations/unstability. I say it probably does not reliably do so because of the less sophisication of just a basic circuit analysis gives. You either have to learn/know the art or use more sophisicated software.
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Cheers.
Quite often IBIS models are far from perfect, requiring a bit of fettling when downloaded. The biggest problem for a lot of firms these days is costs, not only for the software but either having enough engineers to spare one to do the sims or paying for outside consultancy. We had our first few DDR interfaces sims double checked by a consultancy firm to check we were doing it right, not cheap, and when you employ people using Comsol the price sky rockets.
I've had a look at their web site, looks interesting stugg.
Thanks again.
Quite often IBIS models are far from perfect, requiring a bit of fettling when downloaded. The biggest problem for a lot of firms these days is costs, not only for the software but either having enough engineers to spare one to do the sims or paying for outside consultancy. We had our first few DDR interfaces sims double checked by a consultancy firm to check we were doing it right, not cheap, and when you employ people using Comsol the price sky rockets.
I've had a look at their web site, looks interesting stugg.
Thanks again.
Dick said that. And costs millions.
These things are more like $50-$100k a seat for single licenses.
Perfect for a DIYer to reduce his hobby's time.These things are more like $50-$100k a seat for single licenses.
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