N channel mosfets and P channel mosfets are pretty much never having same Ugs voltage
so, no worries
what counts - Iq ( voltage sag across any of 3W source resistors) and output DC Offset
everything else (voltages) is just informative - of special importance if and when troubleshooting
so, no worries
what counts - Iq ( voltage sag across any of 3W source resistors) and output DC Offset
everything else (voltages) is just informative - of special importance if and when troubleshooting
Allan, have you considered increasing the gain a la F5 turbo (using higher values for R9 - R12)?
For 200R 3W, I see some available in Mouser. For example: https://www.mouser.ca/ProductDetail...GAEpiMZZMsPqMdJzcrNwmqCbm4q8Q%2BCdWgGhACmRls=
They're pretty cheap and you can always get a batch and select them if the 5% tolerance worries you.
While you're at it, you might consider increaseing the wattage of R3 and R4. If my understanding is correct, even with standard rail voltage, at high voltage swing (say +/-20V, about 25W into 8 ohms), you are looking at over 1W peak dissipation. And with higher rails, that dissipation potentially can be even higher.
For 200R 3W, I see some available in Mouser. For example: https://www.mouser.ca/ProductDetail...GAEpiMZZMsPqMdJzcrNwmqCbm4q8Q%2BCdWgGhACmRls=
They're pretty cheap and you can always get a batch and select them if the 5% tolerance worries you.
While you're at it, you might consider increaseing the wattage of R3 and R4. If my understanding is correct, even with standard rail voltage, at high voltage swing (say +/-20V, about 25W into 8 ohms), you are looking at over 1W peak dissipation. And with higher rails, that dissipation potentially can be even higher.
Modushop/HiFi2000 is in Italy.
Paging @Gianluca
https://modushop.biz/site/index.php?route=product/category&path=242
Paging @Gianluca
https://modushop.biz/site/index.php?route=product/category&path=242
^ Agreed!
Adding one quick thing....
For anyone wanting pre-drilled heatsinks - Make sure that you order a "Deluxe" chassis or that you specifically tell Modushop that you want "UMS" (Universal Mounting Specification) heatsinks. They're noted specifically, but if I have trouble finding anything, I ask. Gianluca is typically hanging out in the chat window on the lower right of the Modushop web page... and he's awesome!
tl;dr - Not all heatsinks come pre-drilled to fit the diyAudio boards... ask me how I know.
Adding one quick thing....
For anyone wanting pre-drilled heatsinks - Make sure that you order a "Deluxe" chassis or that you specifically tell Modushop that you want "UMS" (Universal Mounting Specification) heatsinks. They're noted specifically, but if I have trouble finding anything, I ask. Gianluca is typically hanging out in the chat window on the lower right of the Modushop web page... and he's awesome!
tl;dr - Not all heatsinks come pre-drilled to fit the diyAudio boards... ask me how I know.
I had a bit of a scare after reinstalling my 2SK1530 / 2SJ201 F5 in a chassis following its several month slumber. After a day of using it I noticed an occasional faint popping in the left channel. Oh no, that’s no good… So I swapped it out with the Scryer again in the main rig and l brooded for a couple days over troubleshooting what component was failing. Audio gods, PLEASE let the outputs still be good, I thought.
I had some time this evening to look it over. While prepping to take several well-lit, close up photos of the board and components, my eye caught something odd on one leg of the big 5W resistor at the back. Eureka! A mere cold solder joint. A quick reflow later, I put the top back on and exchanged the amp again with the Scryer (they are becoming great dance partners) in the main system.
Sweet relief. All is well again.
I had some time this evening to look it over. While prepping to take several well-lit, close up photos of the board and components, my eye caught something odd on one leg of the big 5W resistor at the back. Eureka! A mere cold solder joint. A quick reflow later, I put the top back on and exchanged the amp again with the Scryer (they are becoming great dance partners) in the main system.
Sweet relief. All is well again.
F5Tc V3 Mono Blocs Please!!!one day I'm going to make proper Square Law F5
and F6
and with Pucks
both
F6 D/M Squared done still waiting on me crawling up to the Mill to make legs/handles and take Zen Porn Pics.
Been searching for a good audio DIY project and was recommended to take a look at the F5, and after some hours of reading I decided to give it a try.
Have very limited experience, have built some guitar stuff but lack in the depth of electronic knowhow.
My initial questions is about what components to choose and potential European suppliers.
In the guides i have seen they have used Dale resistors, suppose thats not the only option. Is there any other brand and typ that would be equally good, how to tell if a resistor is suitable for audio designs?
For then PSU i seen Panasonic capacitors, but finds it difficult to find identical capacitors.
Same question, is there any recommended alternatives, and how to tell is the are good or not.
Finally, the transformer, any recommendation there?
Preferably available in Europe?
//George
Have very limited experience, have built some guitar stuff but lack in the depth of electronic knowhow.
My initial questions is about what components to choose and potential European suppliers.
In the guides i have seen they have used Dale resistors, suppose thats not the only option. Is there any other brand and typ that would be equally good, how to tell if a resistor is suitable for audio designs?
For then PSU i seen Panasonic capacitors, but finds it difficult to find identical capacitors.
Same question, is there any recommended alternatives, and how to tell is the are good or not.
Finally, the transformer, any recommendation there?
Preferably available in Europe?
//George
For transformers in Europe, Toridy is often recommended: https://sklep.toroidy.pl/en_US/index
I've ordered from Digikey, Mouser and Newark. I'm sure European members can comment on what suppliers might be more convenient to order from in Europe.
The big Panasonic capactors were discontinued a while back so you likely won't find them any more. I would just stick with any of the big capacitor manufacturers. The obvious things to watch for are capacitance values and voltage ratings. Also don't forget to make sure their dimensions fit whatever power supply PCB you might use. And since you'll be using them in a class A amp you might consider looking for 105C rated caps.
Some of the recent project hasve Vishay SFR resistors in their BOM so they would definitely be suitable choices. I usually just look for 1% metal film resistors. You should filter on dimensions to fit the PCBs as well since I've seen members look for 0.5W resistors and end up with the comically large RN65 ones, which are larger than many 3W resistors.
There's also the upcoming F5m kit that should show up at the store soon. For more about the F5m, you can watch Papa's BAF2023 video (https://burningampfestival.com/videos/). Also check out this thread: https://www.diyaudio.com/community/threads/pass-f5m.406472/
Have fun.
I've ordered from Digikey, Mouser and Newark. I'm sure European members can comment on what suppliers might be more convenient to order from in Europe.
The big Panasonic capactors were discontinued a while back so you likely won't find them any more. I would just stick with any of the big capacitor manufacturers. The obvious things to watch for are capacitance values and voltage ratings. Also don't forget to make sure their dimensions fit whatever power supply PCB you might use. And since you'll be using them in a class A amp you might consider looking for 105C rated caps.
Some of the recent project hasve Vishay SFR resistors in their BOM so they would definitely be suitable choices. I usually just look for 1% metal film resistors. You should filter on dimensions to fit the PCBs as well since I've seen members look for 0.5W resistors and end up with the comically large RN65 ones, which are larger than many 3W resistors.
There's also the upcoming F5m kit that should show up at the store soon. For more about the F5m, you can watch Papa's BAF2023 video (https://burningampfestival.com/videos/). Also check out this thread: https://www.diyaudio.com/community/threads/pass-f5m.406472/
Have fun.
Last edited:
I buy Dale resistors from either Mouser or DigiKey. They are not based in Europe but if you buy up to 40ish EUR they ship for free to Sweden and handle taxes as well. Resistors do not need to be Dale. If you do not have a favorite brand but you buy from the big names (there are plenty more: Elfa, RS, etc.) any brand is good. They just need to fit the specs in the BOM (power) and dimensions of PCB.
Same with caps. Do not have to be Panasonic (I believe no longer in production) but need to be within the specs of the BOM (voltage and physical dimensions).
I have used Toroidy transformers (based in Poland). They are made for audio applications and made to order (2 weeks waiting time).
Same with caps. Do not have to be Panasonic (I believe no longer in production) but need to be within the specs of the BOM (voltage and physical dimensions).
I have used Toroidy transformers (based in Poland). They are made for audio applications and made to order (2 weeks waiting time).
@George_
Welcome! For me, parts selection and understanding what specifications "mattered" over my first few builds was the biggest challenge. I wanted to jump right in and start building. I didn't know resistor ratings / cap ratings etc. etc.
I'd recommend starting with the active and passive devices for now, and then focusing on the chassis and wiring along with other parts you'll need separately.
First, I always start with the latest schematic. You can find that on the store page. I've also attached it.
Without understanding some of it, it's hard to know where to get "matched" parts, and which parts may need to be matched. IMO, the diyaudiostore.com has extremely fair prices on the parts that are harder to get and/or just harder to choose.
Although they are sold out at the moment... I'd get
Then I'd get
That's everything for the amp boards. There's also a "ring style" thermistor I like quite a lot... for TH1 / TH2. I put that in as an alternate part.
These are just suggestions.
Once you sort out the type of power supply you want... then you can have more fun. BTW... if you're going with the Universal PSU boards and the typical First Watt Style Power supply, I'd definitely choose different (cheaper) resistors for R7, and R8 and combine them with your PSU order. You'll find that the same part can be used both places.
Good luck, and have fun!
Edited to add - I don't know why it makes me smile every time I look at this schematic and notice that there's not one, single, capacitor....
Welcome! For me, parts selection and understanding what specifications "mattered" over my first few builds was the biggest challenge. I wanted to jump right in and start building. I didn't know resistor ratings / cap ratings etc. etc.
I'd recommend starting with the active and passive devices for now, and then focusing on the chassis and wiring along with other parts you'll need separately.
First, I always start with the latest schematic. You can find that on the store page. I've also attached it.
Without understanding some of it, it's hard to know where to get "matched" parts, and which parts may need to be matched. IMO, the diyaudiostore.com has extremely fair prices on the parts that are harder to get and/or just harder to choose.
Although they are sold out at the moment... I'd get
This covers Q3 and Q4 along with Q5 and Q6.
Then I'd get
These are some of the harder devices to find, and they need to be matched.
This covers Q1 and Q2 for both channels
The rest of it you can get from one of your local suppliers or on line. I've put a small table below. One of the best things you can take the time to learn is how to upload a BoM into Mouser or other retailers to have it look for your parts. The parts I used with the exception of the Panasonic resistors are all stocked. I've put an (yeh, I know they're expensive) alternative part. Depending on where you order your parts, you can likely find cheaper alternatives. If I were you, I'd leave out P3.That's everything for the amp boards. There's also a "ring style" thermistor I like quite a lot... for TH1 / TH2. I put that in as an alternate part.
These are just suggestions.
Once you sort out the type of power supply you want... then you can have more fun. BTW... if you're going with the Universal PSU boards and the typical First Watt Style Power supply, I'd definitely choose different (cheaper) resistors for R7, and R8 and combine them with your PSU order. You'll find that the same part can be used both places.
| Part | Value | Qty for Stereo Pair | Mouser Part Number | Alternate Mouser Part Number |
| R1 | 4.75k | 2 | 603-MF0207FTE52-4K75 | |
| R2 | 47.5k | 2 | 603-MF0207FTE52-47K5 | |
| R3, R4 | 10R 1W | 4 | 71-CMF6010R000FKEK | |
| R5, 6, 21, 22 | 2.21k | 8 | 603-MFR-25FTE52-2K21 | |
| R7, R8 | .47R 3W | 4 | 667-ERX-3SJR47 | 71-CPF3.475%T00 |
| R9, 10, 11,12 | 100R 3W | 8 | 71-CPF3100R00FKE14 | |
| R13, 14, 17, 18 | 100R | 8 | 594-MBB02070C1000FCT | |
| R15, R16 | 1k | 4 | 603-MF0207FTE52-1K | |
| R19, R20 | 10k | 4 | 603-MF0207FTE52-10K | |
| P1, P2 | 5k | 4 | 652-3296Y-1-502LF | |
| P3 | 200R | 2 | 652-3296Y-1-201LF | |
| TH1, TH2 | 4.7k | 4 | 871-B57164K472J | 594-NTCALUG02A472FA |
| Q1 | 2SK170 | 2 | -N/A- | |
| Q2 | 2SJ74 | 2 | -N/A- | |
| Q3 | IRFP9240 | 2 | 844-IRFP9240PBF | |
| Q4 | IRFP240 | 2 | 844-IRFP240PBF | |
| Q5 | ZTX550 | 2 | 522-ZTX550 | |
| Q6 | ZTX450 | 2 | 522-ZTX450 |
Good luck, and have fun!
Edited to add - I don't know why it makes me smile every time I look at this schematic and notice that there's not one, single, capacitor....
Attachments
Thanks for advise, appreciate it a lot, and well needed
My plan was to get the circuit board for the amp and pcu from the store so if there a new part kit on its way thats perfect.
Even if i plan to follow build guide as precise as possible i hope to use the project to build knowledge.
Is there any article or rule of thumb describing how to design and calculate the capacitor set up for a PCU?
My plan was to get the circuit board for the amp and pcu from the store so if there a new part kit on its way thats perfect.
Even if i plan to follow build guide as precise as possible i hope to use the project to build knowledge.
Is there any article or rule of thumb describing how to design and calculate the capacitor set up for a PCU?