QSPICE Tutorial #1 Audio Amplifier and how to Download

[@fredflintstone8048]

Hey Eddie. Nice job. I'm glad you got on your soapbox for a minute there. Both of those issues are very annoying to me as well. Those who lack putting a zero in front of a decimal point, and also 4 way line intersections that are not clear whether they're just crossovers or if they're joined. I like the way you put it when you stated, 'the art of engineering lost...'

[@KissAnalog]

Thanks so much! I can't help it so I'm sure I'll get on my soapbox once in awhile.

[@trevorhaddox6884]

4-ways make things look nice and keep stuff like totem poles even and neat looking. Despite whatever the "convention" books say I've seen schematics for the past 100 years worth of stuff (vintage gear hobby) use 4-ways just fine. The problem is the dots are too small here, make them say 50% larger and you'll be fine. The dots exist for a reason. In fact I've seen schematics that don't even dot 3-ways, there's no point, obvious connection. But a 4-way gets a big dot.

[@MrBroseph19]

Hey Eddie. I've been really enjoying your Pspice videos, and I see a lot of potential in what you're doing with them. It would be intriguing if you could use Pspice to simulate one of your larger power converter projects and then compare the waveforms between the bench tests and simulations. Highlighting the simulation quirks and explaining the extra elements that might be necessary for representative simulations would be especially informative. Thank you for sharing your content, and I look forward to seeing more!

[@KissAnalog]

Thanks for your feedback! I do plan to design and simulate a power supply for an Audio Amplifier, but in the meantime I will test and simulate some other power supply circuits.

[@EuphoricDan]

Please keep up with the Qspice videos. I'm learning electronics and just got it running (yesterday) on my Linux machine (via a windows VM). I'm looking forward to your future content. Subbed.

[@KissAnalog]

Thanks so much! Did you see my last QSPICE video? kzbin.info/www/bejne/i3LUeY1nnq2mfKM

[@Factory400]

As someone that has struggled to become friends with LT Spice.....I am definitely going to give this a shot.

[@KissAnalog]

I'm right there with you;)

[@jstro-hobbytech]

I'm with you I find it hard which is why I have a box of protoboard circuits. I'd like to see the wolverine circuit in lt

[@KissAnalog]

I'll start the Wolverine Amp in this and see how it goes.

[@dougbas3980]

Thank you. Taking my first look at QSPICE. I have subscribed and plan to watch more of your videos.

[@KissAnalog]

Awesome, thank you! Let me know if there's something that you would like to see;)

[@edwardharvey7687]

I have been using pspice, but I have a big book of guitar amplifier schematics. It is interesting to plug different designs in and see their inner workings in action, if only simulated.

[@KissAnalog]

Yes I agree - it is interesting to simulate a circuit that we have. We can play with values and modify the circuit to see what we can do to improve.

[@johnmusgrave7062]

Edward, I am a guitar amp nerd and learning spice if you can share your collection let me know.

[@qddk9545]

Maybe it is a stupid question, but does that mean that you can simulate tubes, and germanium transistors?

[@garydirkse9900]

Good video, you make it look easy. You have convinced me to try. Congrats on the 25 thousand milestone also.

[@KissAnalog]

Thanks so much!

[@versace885]

HI Eddie, thank you for the informative video. 🙏

[@KissAnalog]

Thanks so much!

[@wagsman9999]

I've finally gotten somewhat (lol) competent with LTSpice. I find simulators a fantastic learning tool (I use them during electronics tutorials). Not sure I want to take the plunge to QSpice yet, I'll keep watching tho.

[@KissAnalog]

Thanks for your feedback! Mike Engelhard wrote both programs so they do seem very similar, but QSPICE is more powerful as this came after LTspice. It is growing and getting updates constantly. We'll have to see what it looks like in a year - it will be even more amazing.

[@waltercheatle1794]

Thanks!

[@KissAnalog]

Thank you for your generosity!!

[@robdavis3220]

change R17 to 390 ohms. Improve THD and see the difference in an fft. Also change the MAX STEP TIME to 500nS or lower , will give you much better resolution for viewing the "spikes" etc

[@KissAnalog]

Thanks I'll give it a try;)

[@bNNjh5fu000jy]

Handy video - thanks

[@KissAnalog]

Thank you!

[@SpinStar1956]

Guess I'm confused: Are the spike/weird waveforms artifacts of QSPICE or the circuit? Does LT-Spice show the same anomalies? I actually have no problem with 2/4-ways but the junction-dot has to be big enough to never miss. I find the offset junctions (just to avoid 2/4-ways) to be messy and confusing (adding visual complexity) only justified by the dots not being big enough!

[@KissAnalog]

Great question! Thanks for bringing this up. I believe it is the circuit that was behaving this way. Once you can see this it can be corrected. Now if it does not show up in the actual physical circuit - then it gives a chance to see why and get the simulation improved to correlate.

[@Gary-ts6dh]

The link to the download came immediately (but, it took me a moment to realize it was in junk.)

[@KissAnalog]

Yes - thanks for bringing that up! I saw on the forum where people are getting the download in their Junk folder. I'll be sure to point this out in the next tutorial;)

[@belaji]

When looking at waveforms, make the background white for heaven's sake.

[@KissAnalog]

Thank you for this feedback! I appreciate you!

[@Peter-W1]

I saw that Micro-Cap home page seems down now so we cant get the free version from there anymore hope some one put up that latest version somewhere.

[@ottoh6498]

wayback machine, feb 14 2023

[@KissAnalog]

Thanks - I heard is up and down, but I really think it is down for good now. You can download the software from this link, but let me know if there are any issues: groups.io/g/FreeEDA-Tools/files/MC12_Files_&_Documents/MC12-2-0-3.zip

[@jstro-hobbytech]

I should try that app. I have thousands of parts to do circuits physically but there's always parts I don't have but cost like 8 dollars a piece haha. Especially opamps.

[@KissAnalog]

Yes simulation can save money in parts. You can play around until you get what you want;)

[@jstro-hobbytech]

Yeah im down with that eddie. I have some repairs and im getting a new phone today so hopefully the images will be better

[@KissAnalog]

Thank you! I need to get a new phone too. I was up at a friends cabin last weekend and no cell service;)

[@jstro-hobbytech]

@KissAnalog my wife was hounding me to switch plans my s23 ultra is almost identical to my s20 or 21. I'm going to side load Linux on my old one I think. Play retro games and use it to keep python off my main pcs. People get paid to code that at Google for like 300k a year and it's like visual basic was in the 90s haha

[@farhadsaberi]

Thank you.

[@KissAnalog]

Thanks for your feedback! I appreciate you!

[@Dave-js1jc]

Eddie, be honest...how many DMM's do you have now? 😊

[@Factory400]

1st guess: All of them 😂

[@hermannschmidt9788]

@@Factory400 Still not enough, the same goes for power supplies 😁

[@KissAnalog]

LOL - I have a couple that I have my eyes on;) I have given a number away as well;) I have another giveaway coming up soon.

[@jstro-hobbytech]

It's an addictive habit. Especially when I collect guitars, recording gear, rc parts, pc hardware, retro gaming consoles and an led collection that rivals the gentleman from the isle of mann haha

[@cougar1861]

Will there be (or has there been) a comparison of Micro-Cap vs QSpice?

[@KissAnalog]

Great question! And yes - I'll do a comparison to show the differences side by side.

[@cougar1861]

@@KissAnalog Good news. Thanks!

[@jstro-hobbytech]

I have the bell hit and it never notified me. Yt is a biotch sometimes haha. I have that amp circuit drawn on paper but haven't tried it yet even though I have all the parts. Ground / return separation for different signals is something I have trouble with when making physical circuits. Schematics don't emphasize that enough but I'm viewing it from an ee hobbyist lens and things that are second nature to some are not clear to plebs like me. I hope that made sense.

[@KissAnalog]

That's a great point about ground vs returns and how they are often not shown correctly or adequately in schematics. I think YT Unsubscribes people too - that's why I ask people to double check to be sure that they are subscribed even if they think they already are.

[@jstro-hobbytech]

@KissAnalog another channel I watch called digital foundry. The owner /host complains about it not working. I don't think it's an un sub but a crappy piece of code. Can you imagine how spaghetti-like this platform's front end python or js code is and the communication with the c++ backend. The ground issue brother is Jat mentioned it in a bunch of videos and explained it well verbally but showing it on a working perfboard amp is hard. I perfboard everything but I'm not at the point where I could build a class ab amp with 2 channels and keep track of signal and power returns and ground. I have made tons of cmos circuits, but with logic circuits it's easy to keep track because you know how every ic works. I have so many ttl and cmos chips and I've given away a ton. This nand to tetris course is cool. Not being clear on the syntax is a bother but I've been figuring it out. It's cool making adders and such out of simple gates I've wrote the hdl for.

[@timthompson468]

Interesting video. For some reason, I’m unable to install QSpice. I get as far as accepting the license agreement, but then when I proceed to install, nothing happens and it shows up as “not responding” in the Task Manager. I’m not sure what’s going on; there are no messages indicating an issue and I’ve installed dozens of programs on this computer without issue. I haven’t found any installation issues online yet, so it may be my system, but my system is a run-of-the-mill HP laptop on Windows 11.

[@KissAnalog]

Thanks for this feedback! That is an interesting problem. Are you signed in as the admin? Is there an antivirus software running? I've not heard of any problems with Windows 11. Maybe join the forum and ask this question. I've seen immediate responses and sometimes from Mike himself.

[@timthompson468]

@@KissAnalog Thanks for the reply. By the way, I forgot to mention in my previous comment that the software download email came in nearly instantly after I signed up for the software. Here are some (gory) details. On the admin issue, I first did not think to “run as administrator” since I usually don’t have to do that, so the dialog popped up prompting me to switch to admin mode. I confirmed that I wanted to switch to admin mode, but then the install program disappears, and I momentarily see an “hourglass” icon but nothing else. I run Task Manager, and there is a QSPICE Installer (32-bit) background task running, but it doesn’t appear to be doing anything; there is 0% CPU access. It also closes the File Explorer app that I used to run the program (I’ve never seen that behavior before). I’ve tried leaving the background task running for over 30 minutes, but it never comes back to show any CPU activity. If I end that task and rerun the installer in Admin mode from the start, I get a little further along. The software downloads and the Installation Program dialog opens. When I accept the license agreement and click “Install” the File Explorer app closes, I get the hourglass icon when hovering on the Install dialog, but nothing more happens. I see an app (as opposed to the “background task” in the earlier attempt) running in Task Manager with “Efficiency mode” shown in the status column (I’m not sure what that means), but there’s no CPU activity shown. When I let that run for a while, I eventually see the “Not responding” note in Task Manger. I ran it a second time, and the “efficiency mode” indicator did not appear the second time but there’s still no CPU activity shown. I did try toggling efficiency mode, but that did not help. I thought it might be my antivirus or, possibly, my firewall. I disabled the firewall temporarily, but that didn’t change the behavior. I checked my antivirus software in case it was blocking the file, but it shows up as “Trusted”, so that seems to be OK. I checked the forum (that’s where I got the idea to check the firewall). I saw a message from Mike on the thread that referred to clearing a cache if the version number is not shown, but I do see the current version number (1.03), so I assume that’s OK. I’ll keep looking into it, and thanks again for your input. I was kind of hoping someone might see my comment and reply with something like “All you’ve got to do is this….” I’m sure others are using this in Windows 11, so I think this issue is somewhat unique to my system. I’ll dig around the forum a little more to see if this has already been addressed, and, if not, I’ll sign up and post it to see if anyone there has an idea. This looks like a cool version of SPICE with a lot of innovative features, so I’d like to get to know it, but it’s not urgent for me right now. Thanks again for the help and the great tutorial video.

[@mp1454]

😀👍🏻

[@KissAnalog]

Thank you!

[@copernicofelinis]

Does it work in emulation under Linux? (Win7 is the last Windows I'm gonna use)

[@KissAnalog]

Great question! It is on their list to add Linux and updates are coming out almost every day.

[@dominikgs]

@@KissAnalog Nice to hear. I think without Linux or at least wine support it will be a death born baby. I remember back in the days as a student nearly everybody runs Linux on their PCs and LTSpice on wine. Nowadays Linux is even more common. I think the success of LTSpice is because of the fact that nearly every student of the early 2000th used LTSpice and those students are the engineers who use it until today. I am one of those guys. I met Mike Engelhard in the past he is a very smart and nice guy.

[@KissAnalog]

I think there's a lot of truth in that;)

[@younesthabet]

I submitted the form like 15 days ago and still hasn't received the download link yet !!

[@KissAnalog]

Thanks for the feedback! I'd try again as I think they were bombarded and I saw that their site went down for at least a day. So I'd try again. Let us know if it works for you.

[@diegogarciamedina6363]

hi, does it have the possibility of import LTSPICE .asc files?

[@KissAnalog]

Yes I think it does have the ability to import an LTspice file, but there might be some adjustments that need to be made. I'll look into this and make a tutorial;)

[@diegogarciamedina6363]

@@KissAnalog Thanks I have a lot of LTSPICE simulations based on libraries, all types of vacuum tubes including heptodes , tunnel diodes, varicaps, mosfets, germanium diodes , germanium transistors and lot of vintage things.

[@KissAnalog]

I think that would be a project for someone to convert them to work in QSPICE. I think it will happen - and just to mention - I think some of these lower level models in LTspice are probably not very good from when I've read. Have they worked well for you?

[@diegogarciamedina6363]

@@KissAnalog yes, they work ok specially electron tubes, tunnel diodes, they work perfectly

[@KissAnalog]

Thanks so much for this feedback!

[@hoobsgroove]

What happened to your voice is gone all deep, like you've got it running too slow, I had to speed up the video to make it sound correct😅

[@KissAnalog]

Sorry about that - I think its the allergies kicking my but!

[@hoobsgroove]

@@KissAnalog yeah it corrected itself after a few minutes, we have to call you the Barry White of electronics 😆

[@KissAnalog]

LOL

[@stefano.a]

Strangely all messages have been placed in spam folder in Gmail

[@KissAnalog]

Thanks for your feedback, but can you explain which messages?

[@stefano.a]

@@KissAnalog messages that contain the download link. I found them there

[@sameerdhiman9381]

First impression was pathetic without crosshair cursur to read values. LTSpice is way more advanced.

[@KissAnalog]

Thanks for your feedback! The man that made LTspice just introduced his new simulation program - QSPICE. There is updates practically every day - where LTspice has not had a major update since Analog Devices bought Linear Technology (where before there was one every year). So, it will not be long before QSPICE is more powerful in every way.

[@sameerdhiman9381]

@@KissAnalog I agree with you. After spending few hours reading help I got it how to attach cursor. Cursor attachment comes with nice feature to align at specific value.👍

[@KissAnalog]

Thanks for this great feedback! The forum is also very good as answers come quickly. I think people are jumping on this and it should grow quickly.

[@GregPeace22]

🤥🤥🤥

[@KissAnalog]

Thanks

[@PoiSonSonic]

09:55 I don't really care what you want, I'm hear to learn stuff. While I develop other software, not QSpice, please forward your wishes on somebody who can fulfil them. Don't make me hear them. I can't help here. Thanks

[@KissAnalog]

Well - was there any positive comment regarding this video that I posted for you to watch for free? BTW, making comments gets back to the vendor and if others have the same feelings - it makes a difference. I hope you learned stuff here...

[@PoiSonSonic]

@@KissAnalog I totally agree with you. If this video had chapters, I could have skipped over what seemed to be directed only at the QSpice devs. That would have been cool. Or what if you could mention that segment and explain everything after the main body of the video? Sometimes that looks good and doesn't disrupt the flow of the narrative. ❤️

[@kenchilton]

4 way intersections + missing leading zeroes + no EDA integration + only runs under Windows = hobbyist toy, not a professional tool

[@KissAnalog]

Thanks for your feedback Ken! But I think we are mixing or confusing user error with applications. It is the user error to make 4 way intersections and to leave off the leading zeros before decimal. I’ve seen this with Altium schematics which is one of the premier board design tools. I think this is a problem with new engineers not being taught the Art of electronics. And from fields like audio where non-engineers designed circuits using earth ground symbols and 4 way intersections as they were never taught the Art of engineering. Regarding this simulation tool - it has just been released and is being updated almost daily. When you say EDA - that is a broad term I think. How do you define that?

[@kenchilton]

@@KissAnalog True, I should not lump in the user mistakes with the application. By EDA integration, I refer to the ability to drive simulation and PCB design, and the thermal, EMI/EMC, and 3D modeling from a comprehensive schematic from which the models, footprints, BOMs, and other data are inferred. ECAD and MCAD create master documents which [should] fully describe the design and I should not have an independent simulation source. The inferences are EDA, automating the electronic design process, and where the connections are not provided by the vendors, I need to be able to write the connectors. I have integrated Hspice and other simulators with several in-house and vendor tools, and have authored a number of model and test generators for SPICE simulations for everything from ASICs to power supplies. Cadence nicely integrated Pspice and Spectre, and KiCAD integrated ngspice, and Altium makes integrating with Pspice or LTspice fairly easy. All of these SPICE versions are pretty easy to get working with just about any CAD system, and the CAD vendors provide at least some level of automation. Qspice is not there yet - not that it won’t be, and I hope it will be soon, but only running under Windows is not helping. I like your comments on other videos about the “non-engineers” who are designing audio equipment. I have worked with a lot of non-engineers who really know their stuff, and only a few others who really could have learned more. Yes, Qspice might be all they need and better than nothing at all. KiCAD is hobbyist level, but I have used it to solve problems for large corporations. I still consider it a toy compared to Allegro. They are in different leagues. What I can accomplish with an Hspice or Spectre AMS is also well ahead of Qspice. I am not trying to just rag on Qspice, but just note that it has a lot of things yet to accomplish to catch up. Again, I hope it does soon, and if I could help it, I would, but they would have to open some avenues for me to do that, such as running on an OS that is made for such things. I can automate many operations using LTspice on a Mac that just are not worth the effort under Windows. Again, I think they will get there, but I am impatient.

[@john762x51]

Tangents and rambling. I am halfway through this video and you have not given me anything that is actually useful, in how to use this software. how do you dare call this a tutorial.

[@KissAnalog]

LOL - did you read the title? At around 3 min I'm showing how to download this (that's in the title), and then I show am amplifier circuit - how to pull it up and how to run a simulation? I have an idea - why don't you dare to leave a comment that is useful? If you want a specific thing showed - then ask for it. I can't read your mind - and you can't read a title. So, how dare you leave such an unworthy comment.

[@bobodyuknow]

Why does this software trigger every single antivirus flag on every system lol

[@KissAnalog]

LOL - do you mean when you try to install it? I think it is because it is an executable file which raises flags. Were you able to download it?