Apparently you failed to notice the very low voltage gain of the amps so missed the amount of NFB. The "opamp-like" stability plot could have provided a clue as well. Apart from that, in the course of time my designs went through all stages of distortion if just because so many designs have been published with both simulated and measured results IOW practice material, examples inviting to be investigated and improved. Learning from omissions and or errors by others became one of my habits about half a century ago. Measurement of one of my low distortion designs will be posted after construction so you'll have to wait for that, or study the design of audio opamps like the LME49860 and apply - whatever suits best.
Yes, but I have a few programs that ran fine under XP but no longer under W7 .... W10. That's a ticking timebomb for any no longer maintained program. But it may have many good years left until it gets there.
Jan
That's why I keep and maintain a fully functional vintage Dell laptop running XP, just in case.
No I didn't, I read the loop plot of NFB. It's physically unrealistic but clear what your simulation value is. Still doesn't explain your unparalleled distortion claims. A typical power amp has a gain around 30, even if you have really low gain, say 3, the distortion could only improve by a factor of 10, far from your claims. And even that is optimistic, it's easy to increase gain almost arbitrarily, the problem is stability at hi frequency, and lower audio band gain doesn't help much there.
Oh, And you have somehow done this vastly better than Audio Precision, Rohde and Schwarz, and every other amplifier builder in the world, ever? What is your R&D expenditure?
I look forward to it.
What is the best result that you have ever actually constructed and verified?Best wishes
David
Dave I would just wait for measurement from a full build with PC layout, power supplies, wiring harness, and finished build driving a real load. Simulations are fantasy.I look forward to it.
Best wishes
David
That's why I keep and maintain a fully functional vintage Dell laptop running XP, just in case.
I hope you have the original install CD with serial number, you'll need it. And never connect it to a network.
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I did after 10yr. because the battery died the clock "lost its mind" and nothing worked. It booted up and it said 150 updates pending, after a day or so of re-booting and downloading everything worked perfectly.
Sure, I meant it when I wrote - "I look forward to it", it's just that I am not optimistic this will actually happen.
On the subject of simulations, I'm not sure Mike E. would take quite the same tone! But aren't your backgrounds similar, from around the same time and both trained in physics rather than EE school?
So have you discussed this with him?
Best wishes
David
Simulated circuits have no physical extent they all exist in the old abstraction of a point in space. There are no coupled fields, delays, etc. in other words a fantasy.
i have installed everything on VMware virtual machines, the win machine with all installed CAD programs etc is just a 50G directory (win XP) or 100G (Win7).
There is also a Win10 machine in the state just before "downgrading" it to win7. There is almost no user data in the virtual machine; instead there is a /d partition in the Linux host that is visible as d: from the windows machines. There reside the circuits, layouts, VHDL designs.
When a machine goes wild, I simply erase it and take a fresh copy from the server. I can also copy the complete environment from the lab workstation to a laptop and just work on. I can isolate a win machine from the network/Internet by just x-ing a checkbox.
There is no perceivable performance loss. I can control the DG8SAQ vector network analyzer from the virtual machines; they are fast enough even though the DG8SAQ VNWA needs its scan data in a bounded time. USB is tunneled transparently.
No batteries required.
There is also a Win10 machine in the state just before "downgrading" it to win7. There is almost no user data in the virtual machine; instead there is a /d partition in the Linux host that is visible as d: from the windows machines. There reside the circuits, layouts, VHDL designs.
When a machine goes wild, I simply erase it and take a fresh copy from the server. I can also copy the complete environment from the lab workstation to a laptop and just work on. I can isolate a win machine from the network/Internet by just x-ing a checkbox.
There is no perceivable performance loss. I can control the DG8SAQ vector network analyzer from the virtual machines; they are fast enough even though the DG8SAQ VNWA needs its scan data in a bounded time. USB is tunneled transparently.
No batteries required.
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Several years ago, facing a similar situation, I installed VMware workstation: a virtual machine that will enable installing XP on it, among others. VMware Workstation Player | VMware
I'm sure you can get vintage XP apps to run one way or another. The point is that it requires time and resources. Only justified if it brings you something you wouldn't have otherwise and you really need it (unless you are a masochist).
By chosing between LTspice and uC12, that is a factor. Does uC12 bring you something that you absolutely need and LTspice doesn't have? Go for it!
Jan
By chosing between LTspice and uC12, that is a factor. Does uC12 bring you something that you absolutely need and LTspice doesn't have? Go for it!
Jan
Hi Edmond
I don't agree. When using the Tian probe in MC10 you have to use the stepping function in the AC analysis to step the "probe". In MC12 you can use the Stability analysis instead of the AC analysis and choose between Tian and Middlebrook analysis and use the stepping function to step all other variables in nested loops. In my opinion that is a step in the right direction.
Stein
Reply to post 66.
Instead of 6Н1П, it is better to use 6Н6П in the driver. Do you have the same circuit in LTspice?
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Microcap Simulation Software Now Free
Hi,
I did complete a search, but no results - Microcap simulation software is now free :
Microcap
Not sure what is happening - but the system does look more like a full featured schematic editor - not explored or used before, as it used to cost.
Regards,
Shadders.
Hi,
I did complete a search, but no results - Microcap simulation software is now free :
Microcap
Not sure what is happening - but the system does look more like a full featured schematic editor - not explored or used before, as it used to cost.
Regards,
Shadders.
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