Okay, "Tell me what you wanted when you built yours, so I may copy you!"
For the very small addition of time and money to add the snubbers, I wanted to sleep well at night (channeling my inner ZenMod). I figured it's so cheap, and takes so little time, why not? I haven't had the opportunity to A/B two like PSU's with and w/out the snubbers, but honestly, I think it helps.
I did buy a ready-to-solder Quasimodo kit to calculate the snubber values. I didn't want to get side tracked on doing that from scratch.
Bonus: I learned a lot about transformers from reading that thread and experimenting with Quasimodo after I built it.
@ Mr. Young.. thanks for the check, it's easy to want to run before you walk. You slowed me me down a bit which was welcome.
@ Fidget I tend to error on the side of caution, snubbers, needed or not, are the way I want to go, (can't hurt right?) but I'm not there on how to do it or where. I have read so meany threads, at some point, there can be too much info and I'm pretty sure I have reached that saturation point. I'll figure it out, but, there is a thing as too much info.
I shall keep looking at the circuit and call out for help as needed..........
JT
@ Fidget I tend to error on the side of caution, snubbers, needed or not, are the way I want to go, (can't hurt right?) but I'm not there on how to do it or where. I have read so meany threads, at some point, there can be too much info and I'm pretty sure I have reached that saturation point. I'll figure it out, but, there is a thing as too much info.
I shall keep looking at the circuit and call out for help as needed..........
JT
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hi my name is jose iracheta. im considering a f6 build. I work as an industrial electrician and I have studied electronics. right now im having trouble finding a transformer that has 400va and 18 volt secondarys. I found one that has 400va and 20 volt secondarys. Is it safe to use this transformer with the f6 kit? Im thinking that its ok but I want to ask someone that has more experiance than me.
I'm a newb, but here are some... I don't know about what physical parameters you, or the build require, but see below. The build says that a 400 or 500 is acceptable.
Transformers - 500VA - Page 1 - AnTek Products Corp
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@jose i, what country are you in? A lot of us in the EU get our transformers (of any voltage) from Toroidy in Poland. I use their "Audio Grade" but some others like the fancy stainless-steel casings on their "Supreme Audio Grade".
To get directly to your question 20V secondaries would be fine on the F5, but I haven't studied the F6 schematic so I'm not 100% sure for it.
Cheers,
Jeff.
To get directly to your question 20V secondaries would be fine on the F5, but I haven't studied the F6 schematic so I'm not 100% sure for it.
Cheers,
Jeff.
You might need to change the zener diode value if you need more bias, but that’s always on a case-by-case basis and has more to do with the Vgs of your mosfets than anything else.
With a 20v transformer you’ll have rail voltages about 1.5v more than what most builders have. (I.E., you’ll have very close to 24v under load, people with 18V transformers have 22.5v or a bit more)
With a 20v transformer you’ll have rail voltages about 1.5v more than what most builders have. (I.E., you’ll have very close to 24v under load, people with 18V transformers have 22.5v or a bit more)
Hello there
Thanks for your guides on this forum!
A bit of intro, I started my DIY life with an Elekit amp and absolutely loved it, so decided to continue my DIY journey with a F6 amp. I'm pretty good at following instructions, but I dont have a solid understanding of everything happening in an amplifier (yet).
I bought the F6 kit the JFSETS, a nice chassis, a 240V (Australia here) to 18V+18V transfo 360 VA and the power supply board. I'm now a bit lost as the BOM for the power supply gives ranges or choices for diodes, resistors, snubber capacitors (with a crazy link to find optimums...).
Is there a "newbie BOM" somewhere?
Could we make a spreadsheet where we pick different parameters (Amps you wanna build (at least the one available on DIY shop), 110/240V, etc) and that would give you what you need? Probably wont be suitable for everyone, but would be lovely for noobs like me
Another noob question: I received 2 sets of Q1/2 Matched IRFP240 MOSFETs. There are 2 matched sets (and not quad matched), should I use a matched pair for a channel or a matched pair for Q1 on each channel?
Many thanks, I hope I was clear in my doubts.
Thanks for your guides on this forum!
A bit of intro, I started my DIY life with an Elekit amp and absolutely loved it, so decided to continue my DIY journey with a F6 amp. I'm pretty good at following instructions, but I dont have a solid understanding of everything happening in an amplifier (yet).
I bought the F6 kit the JFSETS, a nice chassis, a 240V (Australia here) to 18V+18V transfo 360 VA and the power supply board. I'm now a bit lost as the BOM for the power supply gives ranges or choices for diodes, resistors, snubber capacitors (with a crazy link to find optimums...).
Is there a "newbie BOM" somewhere?
Could we make a spreadsheet where we pick different parameters (Amps you wanna build (at least the one available on DIY shop), 110/240V, etc) and that would give you what you need? Probably wont be suitable for everyone, but would be lovely for noobs like me
Another noob question: I received 2 sets of Q1/2 Matched IRFP240 MOSFETs. There are 2 matched sets (and not quad matched), should I use a matched pair for a channel or a matched pair for Q1 on each channel?
Many thanks, I hope I was clear in my doubts.
Hello there
Thanks for your guides on this forum!
A bit of intro, I started my DIY life with an Elekit amp and absolutely loved it, so decided to continue my DIY journey with a F6 amp. I'm pretty good at following instructions, but I dont have a solid understanding of everything happening in an amplifier (yet).
Congratulations for taking the leap! Over the last several months, I built a number of DIY projects including a few First Watt amps, and I still don't understand a lot of what some would call the "basics" happening in an amplifier. I've had a blast learning as I go. I read quite a bit on the net and at least one book that's way over my head, but is amazing... A shameless plug for Bob Cordell's book...
I've found the community here to be exceptionally supportive when I've made an effort to research and then posted detailed questions. Even when I got to my wit's end and just needed a friendly yes or no, someone would kindly provide a bit more info or a precise answer. The trick with DIY (to me) is that there are so many options. The engineering prowess of some of the posters is absolutely remarkable, so while you can get a straight yes or no, on occasion you'll likely get some homework. At least I did. Make the effort (if you have not already) to read the relevant threads from beginning to end. It's tough to find sometimes, but almost all questions have been asked and answered. My personal advice is to build it as simply as possible at first and try your best not to get hung up in the minutia of "best parts". You can go down as many rabbit holes as you want and tweak to your heart's content later after you get the amp up and running.
You'd need to be specific about which parts. I got lost a bit too, and I'd certainly be willing to show you exactly what I used in certain places. Most of it is pretty straight forward with the exception of the snubbers. Someone was kind enough to give me the recommended values for my transformers. I finally understand what they do, but I had to read quite a bit about ringing... what it is, why it happens... what can cause it... etc... The link is likely to the Quasimodo thread. If your exact transformer is listed, then you can use the values in the spreadsheet. If no one has measured your exact transformer, then my personal opinion is that in your situation it will work just fine without an input or output snubber. You can add it later if you choose.
When you're through with the first leg of your journey, you could post your BoM and start to compile itIs there a "newbie BOM" somewhere?
Could we make a spreadsheet where we pick different parameters (Amps you wanna build (at least the one available on DIY shop), 110/240V, etc) and that would give you what you need? Probably wont be suitable for everyone, but would be lovely for noobs like me
. Many people post their BoMs. Some would argue (and recently have) that BoMs in general are for noobs or maybe not good at all. I straddle the fence. Any progress to learn is great, and I certainly wouldn't want people to give up... but making it tooooo easy takes away from the experience. I'll tell you this... if the value is critical, it has a fixed value in the BoM and on the schematic. Picking your own parts is kinda like an initiation, maybe. It took me almost four calendar weeks (roughly 40 man hours invested in spare time) to FINALLY get a full BoM with in-stock parts together for my first amp / PSU / chassis and accessories, and I still made errors. It sucked when all I wanted to do was build... and I couldn't get a parts list finalized. I learned a lot from that experience. A big shipping bill for a missed or incorrect component is sobering. It sucks, I maybe yelled... That question should ideally be in the F6 thread. It's also been answered a number of times. That one, even I won't give you a direct YES/NO for. If you've looked around thoughtfully, and got frustrated, look once again. If you still can't find an answer, post over there. Show where you've looked. For me anyway, beginning to learn which FETs need to be matched and why was a bit of a breakthrough in learning. Still and all, if you're not there yet, just ask. Everyone wants you to have a successful build, but it's doubtful that you'll get a full set of instructions. They are after all build "guides".
If it helps, I put up a thread about building my first First Watt (the M2x). I included a lot of the decisions I made and why I made them along with the guidance I got when I hit a few walls. I was/am in your shoes and wanted a lot of the information you now seek. If it helps you, wonderful. If not, then it won't take too long to read my BS
I didn't build the F6, but a chunk of the information could apply.Congratulations again, and enjoy the build!
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If you build the complete discrete diode bridge as is on the PSU board from the store—it's very difficult to add the input snubbers later—perhaps from the bottom of the board though? They are buried among the diodes and the heatsinks.
I know only enough about all of this to get into trouble‚ had some great help, especially from 6L6 and fidget—I built an F5 and the full PSU and built the Quasimodo board to calc the input snubbers on the PSUs discrete diode bridge—I didn't know about the spreadsheet of values, Ha! until just reading this (where is that?)—but I would have done what I did regardless. It was amazing. Can't wait to build another amp. F5 sounds incredible.
I would completely recommend going the hard route there... You need a scope though. The Quasimodo board kit is available from member dsolodov. Find the thread and PM him. I powered mine with a 9V battery. I'll be posting the experience at some point on that thread. It will be completely noobie in nature.
@ItsAllInMyHead — thanks for mentioning some reading. Been looking for something like that!
@JulesOz — PM me and I'll gladly share the BOM I put together for the PSU. The store indicates that the same PSU works for a lot of these amps. What I built for the F5 would work for the F6 as far as I know.
Attachments
I wanted to throw out another question...
Is there a "quality" factor in transformer design? Say Toroid vs Antek for a 400VA 2x18V transformer? Or is it the law of diminishing returns? The Toroid being more expensive—just for kicks, since the Antek AS-4218 has been out of stock for some time—probably due to this forum (they have 6 now)—I got a quote for a transformer from Toroid (they have a great logo haha.).... They want some big bucks for it comparatively (if you buy just one) unless you can buy like 100 of them... their price is still double Antek if you buy 10+ at a time. Toroid however sent a very detailed spec sheet for their transformer.
If there is a quality thing here... and there's a reason to do anything (and spend double on a transformer)... I'd be willing to do a group buy.
Is there a "quality" factor in transformer design? Say Toroid vs Antek for a 400VA 2x18V transformer? Or is it the law of diminishing returns? The Toroid being more expensive—just for kicks, since the Antek AS-4218 has been out of stock for some time—probably due to this forum (they have 6 now)—I got a quote for a transformer from Toroid (they have a great logo haha.).... They want some big bucks for it comparatively (if you buy just one) unless you can buy like 100 of them... their price is still double Antek if you buy 10+ at a time. Toroid however sent a very detailed spec sheet for their transformer.
If there is a quality thing here... and there's a reason to do anything (and spend double on a transformer)... I'd be willing to do a group buy.
What brand do you mean by toroid?
Is it the below?
Power transformers - Shop Toroidy.pl
If yes, they also have 3 different lines: e.g. standard, audio, supreme audio. I wonder which one you compare to?
Correct, and I agree. However it's not "difficult" per se. YMMV. They're small parts and if the PSU is raised on standoffs, they can be added to the bottom with little more effort than adding them during the initial build. You'd almost definitely need to take the PSU out of the chassis, which would take some time, but for the person that assembled it, should not be too challenging to remove and replace.
I may be mistaken. I thought there was a spreadsheet somewhere... I'll keep looking. In the interim, this is the place to start. https://www.diyaudio.com/forums/power-supplies/313202-quasimodo-results.html#post5206650
Can't wait to see what you've learned. I have not tried the Quasimodo yet.
My pleasure.
+1. One of my goals was to use the same PSUs for all FW variants. So far, M2x, Aleph J, SissySIT, F4, and F5.
Comparing the specs (or providing them here) of the Toroid model (assuming Toroid Corporation, US manufacturer of Toroidal Magnetic Components) you were quoted vs. the Antek may provide some clues re: claimed performance, but it may be simply economies of scale. Without the specs, there's no way to know for those specific ones. In general, yes - some transformers are better suited to applications than others. I learned a bit when comparing Antek's AN line to their AS line as an example. I'm confident that I've read somewhere that ZenMod has his toroids made in a way he appreciates. Since I can't find the specifics at the moment, he may elaborate.
Edited to add - looks like the right source per your follow up post.
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The Antek can be used with 110V or 220V mains. The Toroid can only be used with 110V.
Cheers,
Jeff.
