'd like to use the PSU board to build the Pearl 2. I can find a few examples of where people have done this, but none where it is explained how to go from Wayne's example PSU to the Universal PSU board. It is very obvious that the Universal PSU board is a real Swiss army knife, but the actual BOM of the board and how to stuff the board isn't obvious to me.This is my first build that involves a PSU and my second build ever. I've spent a fair amount of time reading the different threads and I'm only more confused. Can someone point me in the right direction to get me started? Thanks,
Do you plan to copy waynes example using this board or build a beefed up supply? Wayne’s example is basically just two 10.000 uf caps after the diode bridges do you really only need half the board making it a bit silly, or you can split into 2x5000 uf per cap bank but I don’t think it makes any difference.
I was planning on copying Wayne's example, unless Wayne or others have found it could use an little upgrade since the design was published. I'd also like to understand WHY Wayne made the choices he did, otherwise I'm just copying.
It is my understanding that you'd need the whole board to copy the design since Wayne intended to have two rectifier bridges: "We do this because the positive rail will be sourcing more current to the circuit than the negative, and in this circumstance dual rectifiers will avoid the transformer noise which often accompanies this."
What I"m struggling with is going from this (PassDiy) to this (https://cdn.shopify.com/s/files/1/1006/5046/files/P-PSU-1V30-schematic.pdf) because there are sooooo many options on the board, and particularly since this is all new to me. Maybe it will be obvious once I've completed it, but I'm not there yet.
It is my understanding that you'd need the whole board to copy the design since Wayne intended to have two rectifier bridges: "We do this because the positive rail will be sourcing more current to the circuit than the negative, and in this circumstance dual rectifiers will avoid the transformer noise which often accompanies this."
What I"m struggling with is going from this (PassDiy) to this (https://cdn.shopify.com/s/files/1/1006/5046/files/P-PSU-1V30-schematic.pdf) because there are sooooo many options on the board, and particularly since this is all new to me. Maybe it will be obvious once I've completed it, but I'm not there yet.
No what i meant was that the board has room for a full Crc but you will only use the first c, so you will occupy a lot of space with unpopulated pcb. Whether that is a problem at all depends.
As for rectifiers, you can use diode breakaway board or I suppose standalone bridges. Each rectifier has a + and - out, and you invert one with respect to the other to get a bipolar supply. This is standard use of this pcb so no difference there. You can look at the f5/f6 build guides by 6l6 to get a visual idea. Unfortunately the schematic you found is not the most helpful, as it shows you all the possible configurations.
In essence what you need to do is put 10.000 uf in C1 and C3 and ignore the rest of the filter section of the board.
As for rectifiers, you can use diode breakaway board or I suppose standalone bridges. Each rectifier has a + and - out, and you invert one with respect to the other to get a bipolar supply. This is standard use of this pcb so no difference there. You can look at the f5/f6 build guides by 6l6 to get a visual idea. Unfortunately the schematic you found is not the most helpful, as it shows you all the possible configurations.
In essence what you need to do is put 10.000 uf in C1 and C3 and ignore the rest of the filter section of the board.
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I expected that the example schematic that Wayne included in the example power supply was more of a concept - level example and I expect that the build by 6L6 for the Pearl 2 is closer to what Wayne had implied in the example. I understand 6L6's schematic (which he notes he got from Wayne at Burning Amp, I believe), but I'm very confused how to implement those specifics on the Universal board... too many options (6L6 didn't use the Universal board).
The F5/6 examples just shows stuffed boards and don't mention anything about how the components were selected or the logic for the parts placement. When doing this for the first time I could place a part in every location according to the BOM and maybe-it-works-maybe-it-doesn't, but that doesn't mean it is correct or that I've learned anything.
As a first-timer I need a few extra steps to get me going, and that's what i'm asking for: where on the forums can I find guidance on the first few steps for the Pearl 2 application of the Universal board, or can someone provide that for me (and the other newbies)?. Thanks,
The F5/6 examples just shows stuffed boards and don't mention anything about how the components were selected or the logic for the parts placement. When doing this for the first time I could place a part in every location according to the BOM and maybe-it-works-maybe-it-doesn't, but that doesn't mean it is correct or that I've learned anything.
As a first-timer I need a few extra steps to get me going, and that's what i'm asking for: where on the forums can I find guidance on the first few steps for the Pearl 2 application of the Universal board, or can someone provide that for me (and the other newbies)?. Thanks,
Ok, well 6L6 uses a CRCRC psu, this you cannot do on the diyaudio universal board.
Perhaps you should query the original thread to see what Wayne's and other's takes are. I could imagine 6L6's example is over the top (which is of course fine and perfectly reasonable in DIY
).He provides more ripple reduction, but with only around 100 mA current draw, the ripple is probably already pretty small.
Alternatively, you could simply forgo the universal board and copy 6L6's example, it is very well documented after all. Three 6800 µF caps (50V) per rail, connected via 10 ohm resistors (3W, those are the red ones in his pictures). He also has a bleeder to drain voltage to ground (blue) when the amp is switched off. The snubber is optional and may need to be optimized for the specific transformer to work properly, but it does no harm even if its not dampening much. Now 6L6 also had to increase the R to drop enough voltage for the pearl2 regulators, and unfortunately doesnt give the value of the resistors. But you could probably get around this by using a transformer with lover voltage secondaries. Say you want around 29V, you could chose 20 or 21V secondaries (and maybe reduce the value of your 10 ohm resistors a bit).
Perhaps you should query the original thread to see what Wayne's and other's takes are. I could imagine 6L6's example is over the top (which is of course fine and perfectly reasonable in DIY
).He provides more ripple reduction, but with only around 100 mA current draw, the ripple is probably already pretty small.Alternatively, you could simply forgo the universal board and copy 6L6's example, it is very well documented after all. Three 6800 µF caps (50V) per rail, connected via 10 ohm resistors (3W, those are the red ones in his pictures). He also has a bleeder to drain voltage to ground (blue) when the amp is switched off. The snubber is optional and may need to be optimized for the specific transformer to work properly, but it does no harm even if its not dampening much. Now 6L6 also had to increase the R to drop enough voltage for the pearl2 regulators, and unfortunately doesnt give the value of the resistors. But you could probably get around this by using a transformer with lover voltage secondaries. Say you want around 29V, you could chose 20 or 21V secondaries (and maybe reduce the value of your 10 ohm resistors a bit).
Hi! Been watching the thread a bit and haven't had the chance to reply.
Yes, you can use the universal PSU board, it will work great, and yes, it's overkill.
As for parts, you are correct in thinking that you don't want to stuff everything. This is a raw supply, the values given in the article's example or my guide's example are just variations on the theme, as the board itself has a ton of capacitance, CRC, regulators, and local decoupling in a few spots.
Get 4 caps the fit the PCB, (10mm lead spacing, 'snap-in', 50V+, max diameter 35mm) 2 10ohm 3W resistors for the R section, and 2.2K 3W bleeders. LED to taste and use about 15K for the LED resistors (1.4w is fine) Bridges can be whatever you like. 1N4004 diodes (not as bad as you might think...) or something fancy and expensive. Yes, the PCB will be mostly empty.
Check your PM
Yes, you can use the universal PSU board, it will work great, and yes, it's overkill.
As for parts, you are correct in thinking that you don't want to stuff everything. This is a raw supply, the values given in the article's example or my guide's example are just variations on the theme, as the board itself has a ton of capacitance, CRC, regulators, and local decoupling in a few spots.
Get 4 caps the fit the PCB, (10mm lead spacing, 'snap-in', 50V+, max diameter 35mm) 2 10ohm 3W resistors for the R section, and 2.2K 3W bleeders. LED to taste and use about 15K for the LED resistors (1.4w is fine) Bridges can be whatever you like. 1N4004 diodes (not as bad as you might think...) or something fancy and expensive. Yes, the PCB will be mostly empty.
Check your PM
Hello friends!
I have a question regarding one PSU capacitor (C9 from the usual FirstWatt PSU), which is actually not soldered to this PCB but which is placed between the two input thermistors (before the transformer).
It's C9: .0033uF LINE??? I don't know what 'line' means, nor what type of Cap this should be? Ceramic? Also metal? What voltage? (does this depend on whether its 240 or 120?)
Thanks for any info, best regards,
Rafa.
I have a question regarding one PSU capacitor (C9 from the usual FirstWatt PSU), which is actually not soldered to this PCB but which is placed between the two input thermistors (before the transformer).
It's C9: .0033uF LINE??? I don't know what 'line' means, nor what type of Cap this should be? Ceramic? Also metal? What voltage? (does this depend on whether its 240 or 120?)
Thanks for any info, best regards,
Rafa.
Hi Rafa,
This link should help explain the function of line capacitors:
Safety Capacitors First: Class-X and Class-Y Capacitors
Here is the line capacitor I use in Pass builds:
ECQ-U2A332ML Panasonic Electronic Components | Capacitors | DigiKey
Hello friends. I am a complete DIY newb. An enthusiastic one but a newb nonetheless. I have built the ACA 1.6 and am now going to attempt the Aleph J, which requires that I build a PS. The instructions on page 1 are clear, however I couldn't find what kind of toroidal transformer to get and how to connect it. Any help with this would be hugely appreciated. Thanks,
John
John
Antek AS-3218 or AS-4218 are both good choices.
http://www.antekinc.com/content/AS-3218.pdf
http://www.antekinc.com/content/AS-4218.pdf
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Cromer, the f6 needs a bipolar supply. The aca is only +24 and gnd.
I also highly doubt you can join 2 together to form a bipolar device. You can in certain circumstances join 2 together to form higher voltage supplies but from a quick Google search it seems to come with a lot of caveats and theres lots of ways that can go wrong.
The DIY psu is absolutely perfect for these amps, I strongly suggest using that design as it's tried and tested and limits opportunity for blowing things up or just not really working as expected. Even if the aca supplies worked in series, you'd probably need 4 of them which could well be more expensive than the linear psu.
I also highly doubt you can join 2 together to form a bipolar device. You can in certain circumstances join 2 together to form higher voltage supplies but from a quick Google search it seems to come with a lot of caveats and theres lots of ways that can go wrong.
The DIY psu is absolutely perfect for these amps, I strongly suggest using that design as it's tried and tested and limits opportunity for blowing things up or just not really working as expected. Even if the aca supplies worked in series, you'd probably need 4 of them which could well be more expensive than the linear psu.
6L6 I'm building a PSU for a BBA-3. 32+- Output. Using a AN-6224 transformer. Do I need input and/or output snubbers? Resistor snubbers in and/or out? It seems that I do not. If I do could you provide part #s or the critical specs. The Note 4 Article from the BOM made my head spin.
Also which blue LEDs did you use in the BA-3 build guide? I think you used 2.2K resistors for the LED can you confirm that?
Also which blue LEDs did you use in the BA-3 build guide? I think you used 2.2K resistors for the LED can you confirm that?
