Hi All, i have just bought PCB for this project and started sourcing parts. Would be grateful for advice if it is worth to upgrade internal wiring cables and into what?
I see the standard cables are cat 5/6 but i have seen people used belden/duelund cables. Is it worth doing or cat 5/6 are fine?
I see the standard cables are cat 5/6 but i have seen people used belden/duelund cables. Is it worth doing or cat 5/6 are fine?
Just finished up my B1 tonight! Was a fun build, cute little guy for sure. wow, killer sound! I had previously hooked up my (also new build) ACA to the pre-out on my old Marantz and the ACA was great but running off the KorgB1 its even better no questions
A couple odd things I ran into - I bought a triad 24V WDU25-500. When I did the voltage checks everything on the power supply side was a bit high. The power at the plug is a touch over 26vDC. I swapped for the laptop style that came with my ACA kit and it all came within spec. Is there any harm running it with the slightly hotter wall wort supply? Should I exchange / return for one that's closer to 24 or is that totally overkill and not necessary?
The other issue was a bit of an oversite on my end. The 1000uf caps I bought were Elna ROA 1000uf 25v. When I went to "close the hood" on my chassis I discovered they sit a bit taller than I anticipated. Ooops. One factor I honestly didn't even consider when making my shopping list. I have the board sitting on 1/2" nylon spacers which I could possibly chop shorter to make things fit but it'll be really close. I think my kid stole the brass ones but I didn't see an issue not grounding every screw since everything is grounded through the board trace. Is that ok thinking?
Regarding the tall caps- My other thought was could I directly mount the board to the chassis if I put something to insulate the bottom from the chassis plate? I have some thin kydex that would fit the bill perfectly and maybe pad it slightly with something like thin closed cell foam? Might help with microphonics as an added bonus 🙂 Obviously the "correct" thing to do is pull the caps and replace with something shorter or just cut a hood scoop and let them fly out the top with some clear plexy to see the cool tube glow!
A couple odd things I ran into - I bought a triad 24V WDU25-500. When I did the voltage checks everything on the power supply side was a bit high. The power at the plug is a touch over 26vDC. I swapped for the laptop style that came with my ACA kit and it all came within spec. Is there any harm running it with the slightly hotter wall wort supply? Should I exchange / return for one that's closer to 24 or is that totally overkill and not necessary?
The other issue was a bit of an oversite on my end. The 1000uf caps I bought were Elna ROA 1000uf 25v. When I went to "close the hood" on my chassis I discovered they sit a bit taller than I anticipated. Ooops. One factor I honestly didn't even consider when making my shopping list. I have the board sitting on 1/2" nylon spacers which I could possibly chop shorter to make things fit but it'll be really close. I think my kid stole the brass ones but I didn't see an issue not grounding every screw since everything is grounded through the board trace. Is that ok thinking?
Regarding the tall caps- My other thought was could I directly mount the board to the chassis if I put something to insulate the bottom from the chassis plate? I have some thin kydex that would fit the bill perfectly and maybe pad it slightly with something like thin closed cell foam? Might help with microphonics as an added bonus 🙂 Obviously the "correct" thing to do is pull the caps and replace with something shorter or just cut a hood scoop and let them fly out the top with some clear plexy to see the cool tube glow!
Hello,
It is indeed odd that your regulated SMPS delivers 26V instead of 24V. Just double check with a 100% fail safe multimeter with working batteries it is indeed the case.
If so, I would return it if still possible.
I wouldn't use it with the B1K because, although it is true caps have a small tolerance re rating usualy, the caps recommended with the B1K are 25V max, so at some points you are exceeding it (not even mentioning start up peaks etc.). I don't remember the schematic of the kit offered today, but the first cap of the PS, the one after the first R in the RC filtering network, "sees" in fact something like 23,4V when using a 24V PS (say 0.4V loss due to the 10R). Means in your case probably 25,4V. At least that one should be uprated, and also the "next cap" after the second R, but that would still mean running the board at a higher voltage than intented, so requires some thinking.
Alternatively, if really stuck, I would consider increasing the R value in the RC networks so that it would in fact lead to having a 24V PS as seen from the board, and that would be easier IMHO provided your PS has enough power reserve to allow for the extra associated losses...
"Grouding the mounting screws" if fine. Yep, insulating the bottom would also work, but probably also bring some parasitic capacitance etc. into play IF touching the board, so I would first try "acceptably short" feet.
Good luck!
Claude
It is indeed odd that your regulated SMPS delivers 26V instead of 24V. Just double check with a 100% fail safe multimeter with working batteries it is indeed the case.
If so, I would return it if still possible.
I wouldn't use it with the B1K because, although it is true caps have a small tolerance re rating usualy, the caps recommended with the B1K are 25V max, so at some points you are exceeding it (not even mentioning start up peaks etc.). I don't remember the schematic of the kit offered today, but the first cap of the PS, the one after the first R in the RC filtering network, "sees" in fact something like 23,4V when using a 24V PS (say 0.4V loss due to the 10R). Means in your case probably 25,4V. At least that one should be uprated, and also the "next cap" after the second R, but that would still mean running the board at a higher voltage than intented, so requires some thinking.
Alternatively, if really stuck, I would consider increasing the R value in the RC networks so that it would in fact lead to having a 24V PS as seen from the board, and that would be easier IMHO provided your PS has enough power reserve to allow for the extra associated losses...
"Grouding the mounting screws" if fine. Yep, insulating the bottom would also work, but probably also bring some parasitic capacitance etc. into play IF touching the board, so I would first try "acceptably short" feet.
Good luck!
Claude
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If I am not mistaken... and very quickly...
If we want say 22.8V to 23V at F, I believe that was the initial intention...
When having 26V AT THE BOARD (so loaded etc.) instead of 24V, we need to lose 2 extra Volts, so say 1V per R in the initial RC network.
If drawing 50 to 60mA, that would mean swaping the two 10R resistors for two 30R ones, which also helps the filtering BTW
The associated extra power loss swapping the 10R resistors with 30R ones is two times 0,07W, so 0,14W, so should pose no prob to your PS with its 12W.
As for the power rating of the resistors, simple 1/2W should do the trick but I can see that Papa used 3W resistors here so there must be a reason (start up??) and so perhaps I missed something... in any case I would at least use 3W ones aswell...
Off to work, sorry, perhaps others can help further!
Claude
If we want say 22.8V to 23V at F, I believe that was the initial intention...
When having 26V AT THE BOARD (so loaded etc.) instead of 24V, we need to lose 2 extra Volts, so say 1V per R in the initial RC network.
If drawing 50 to 60mA, that would mean swaping the two 10R resistors for two 30R ones, which also helps the filtering BTW
The associated extra power loss swapping the 10R resistors with 30R ones is two times 0,07W, so 0,14W, so should pose no prob to your PS with its 12W.
As for the power rating of the resistors, simple 1/2W should do the trick but I can see that Papa used 3W resistors here so there must be a reason (start up??) and so perhaps I missed something... in any case I would at least use 3W ones aswell...
Off to work, sorry, perhaps others can help further!
Claude
This may be helpful...
The supply included with the kits is a WSU240-0500, which is a regulated supply.
The WDU25-500 is not a regulated supply.
The supply included with the kits is a WSU240-0500, which is a regulated supply.
Ahhhh... That's indeed a useful input!
If your PS is not regulated, sadly you have to measure voltage at the input of the B1K when running and hope for the best.
That is that it is close to 24V loaded ...or that it gets there once the RC network has been modified accordingly as stated above.
Having said that, I would rather stick to the recommended regulated PS or better... safety, ripple etc.
SMPS + as an option one of Mark's fab SMPS filter works beautifully well... why bother...
Have fun
Claude
If your PS is not regulated, sadly you have to measure voltage at the input of the B1K when running and hope for the best.
That is that it is close to 24V loaded ...or that it gets there once the RC network has been modified accordingly as stated above.
Having said that, I would rather stick to the recommended regulated PS or better... safety, ripple etc.
SMPS + as an option one of Mark's fab SMPS filter works beautifully well... why bother...
Have fun
Claude
Good to know! I just bought the board / jfets and chassis as the whole kit wasn't available and I'd prefer picking my own parts. The only post I came across was the power supply should be 500mA and 24V but luck would have it I actually bought the WDU25-500 and a WSU240-500 so problem solved! Plugged in the WSU and everything is happy. Set T6/7 to 10v and it sounds good.
Is there a power supply like the laptop style that comes with the ACA that would be an upgrade from the wall wart? I like the idea of keeping mains voltage out so not considering a chassis mount power supply board at the moment. The SMPS filter sounds interesting though I'm not getting any hum or noise - are there other sonic benefits to the filter?
Thank you and merci!
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Glad you are sorted!
Of course there are different SMPS, some with more or less ripple and noise and power etc., which MAY sound different.
Given the nature of this unit, I found Mark's little SMPS filter to be a small but worthwhile addition. The beauty of this filter is that it will filter any SMPS to a high degree, so that IMHO it lessens ON THIS UNIT quite a bit the impact of different SMPS. In short, save your money and don't buy another SMPS, simply fit a SMPS filter and possibly consider the other tweaks, that would be my priority. If you like playing, once everything is optimised to your ears you MAY try, or not, a "better" SMPS on the B1K..
Last but not least, the B1K doesn't hiss or make noise as it comes, without filter. Papa did - of course - a great job! Mark's SMPS filter can have various benefits to the sound that are not related to simple hum or hiss. Things such as impact, bass or treble extension, transparency, soundstage, leading edge of notes or ending of notes ... The differences with and without filter depend mainly on your SMPS and your... hearing!
Mark's filters are a very resonable investment and TBH and I find in 99% of the cases it was designed for it is either benefical or (very rarely) neutral... so it will be usefull on several units, it is always good to have one lying around. I have several PO89ZBs (on my systems and even 2 for friends to try out) but I have no reason to doubt that the more recent and on the paper even more effective AmyAlice (also designed by Mark) wouldn't work great.
I hope this helps
Claude
Of course there are different SMPS, some with more or less ripple and noise and power etc., which MAY sound different.
Given the nature of this unit, I found Mark's little SMPS filter to be a small but worthwhile addition. The beauty of this filter is that it will filter any SMPS to a high degree, so that IMHO it lessens ON THIS UNIT quite a bit the impact of different SMPS. In short, save your money and don't buy another SMPS, simply fit a SMPS filter and possibly consider the other tweaks, that would be my priority. If you like playing, once everything is optimised to your ears you MAY try, or not, a "better" SMPS on the B1K..
Last but not least, the B1K doesn't hiss or make noise as it comes, without filter. Papa did - of course - a great job! Mark's SMPS filter can have various benefits to the sound that are not related to simple hum or hiss. Things such as impact, bass or treble extension, transparency, soundstage, leading edge of notes or ending of notes ... The differences with and without filter depend mainly on your SMPS and your... hearing!
Mark's filters are a very resonable investment and TBH and I find in 99% of the cases it was designed for it is either benefical or (very rarely) neutral... so it will be usefull on several units, it is always good to have one lying around. I have several PO89ZBs (on my systems and even 2 for friends to try out) but I have no reason to doubt that the more recent and on the paper even more effective AmyAlice (also designed by Mark) wouldn't work great.
I hope this helps
Claude
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@blue360cuda - That's what I'd call being prepared!
re: improvements from changing PSUs. I admit I'm not well-equipped to answer that question from personal experience. My hearing is likely orders of magnitude "worse" than most, and there are a number of times when I can't reliably discern between what some describe as "night and day" differences.
I do know that Mark's filters perform exceptionally well and that I've used a few. Whether I can tell a difference in the music... I truly don't know. However, they're relatively inexpensive and super fun to build. Also, if (like me) you may be learning about how to measure more things with an oscilloscope and other test gear to see how it affects the signal (or just PSU performance) or if you just like to see how a 'properly designed' SMPS filter performs... it's a blast.
re: improvements from changing PSUs. I admit I'm not well-equipped to answer that question from personal experience. My hearing is likely orders of magnitude "worse" than most, and there are a number of times when I can't reliably discern between what some describe as "night and day" differences.
I do know that Mark's filters perform exceptionally well and that I've used a few. Whether I can tell a difference in the music... I truly don't know. However, they're relatively inexpensive and super fun to build. Also, if (like me) you may be learning about how to measure more things with an oscilloscope and other test gear to see how it affects the signal (or just PSU performance) or if you just like to see how a 'properly designed' SMPS filter performs... it's a blast.
Blue360cuda...
If you are looking for "upgrade tweaks" when building you B1K, besides the two boards mentioned by Claude above are two more things. The first is actually another of Claude's ideas is the use of a Murata 1433428C coil for additional SMPS filtering in his ACA mini build (from here, post 2874, https://www.diyaudio.com/community/threads/diy-aca-mini.379037/page-144#post-7706477). I added one of the coils on the output of MJ's PO89ZBs wherever I was using one (mostly on my original B1K builds). I'm not a scope guy but I thought it could either help or just be neutral at worst. The second is a slow startup/heater circuit created by Zen Mod (https://www.diyaudio.com/community/...-b1-zms-soft-heat-design.421730/#post-7936221) which is supposed to improve longevity of the Korg Nutube. Numerous people have complained about one channel of their Nutube burning out due to (?) the initial surge of power on in the N1K circuit.
For power supply options, I'll add two that I've used. The first is a Meanwell LRS-150-24 (kinda overkill for what the B1K needs) which is pretty clean as far as electrical supply noise goes. I added the above mentioned AmyAlice filter after its output (but you need a bit of proficiency soldering SMD parts to build it) for further cleanup. Necessary? Don't know but it certainly doesn't hurt especially since MJ designed it. The second option is building a regulated linear PS for your build. I used one made by Gaz2613 called the single rail "Artemis" but used a Sparkos regulator (24V) instead of the normal 78xx regulator in the BOM. It's a CRCRC filtered board so it's pretty quiet. Whether Gaz2613 sells these boards anymore is unknown.
Cheers,
Pete
Be Prepared! Old boy scout motto 😉 I was honestly surprised I couldn't find what the factory power supply was anywhere and I dug pretty hard so figured 2 shots is better than 1 and it paid off lol.
I'll put one or two of those SMPS filter kits in my cart. Maybe throw one in the ACA as well. Has anyone squeezed one in the B1 chassis ? I saw a couple guys rigged up outboard boxes out of altoid tins or small chassis. I wonder if the Meanwell 24v that came with my ACA could serve double duty and power both units by rigging up an outboard filter with two power outs? Since the B1 only needs 500mA the Meanwell should have enough to spare? Could even mount it inside the ACA since there's more real estate and add a 2.5mm power jack then do a short male-male plug and daisy chain the B1 off the ACA and both will be filtered.
Ideally I'd like to figure out an external power supply with an IEC plug and 4 or so outputs for whatever voltages are necessary by just choosing the right resistor combo. Has anyone done an adjustable power supply with ladder or parallel resistors like used in a stepped attenuator for volume control? Not sure how much power the boards on available ones like goldpoint could handle since they're not really designed for that. Could always rig up a custom point to point one with 1 or 2 rotary switches rated for the appropriate load. My one tube amp I built has a similar set up for the volume with a coarse and fine adjustment. Maybe even a small voltage display with selector switch for each output ? fun stuff
I'll put one or two of those SMPS filter kits in my cart. Maybe throw one in the ACA as well. Has anyone squeezed one in the B1 chassis ? I saw a couple guys rigged up outboard boxes out of altoid tins or small chassis. I wonder if the Meanwell 24v that came with my ACA could serve double duty and power both units by rigging up an outboard filter with two power outs? Since the B1 only needs 500mA the Meanwell should have enough to spare? Could even mount it inside the ACA since there's more real estate and add a 2.5mm power jack then do a short male-male plug and daisy chain the B1 off the ACA and both will be filtered.
Ideally I'd like to figure out an external power supply with an IEC plug and 4 or so outputs for whatever voltages are necessary by just choosing the right resistor combo. Has anyone done an adjustable power supply with ladder or parallel resistors like used in a stepped attenuator for volume control? Not sure how much power the boards on available ones like goldpoint could handle since they're not really designed for that. Could always rig up a custom point to point one with 1 or 2 rotary switches rated for the appropriate load. My one tube amp I built has a similar set up for the volume with a coarse and fine adjustment. Maybe even a small voltage display with selector switch for each output ? fun stuff
While it is perfectly feasible, it is difficult to forsee if powering the ACA and the B1K from a single very large 24V SMPS is benefical or not (despite using oversized SMPS it seems it always bounced back when we tried with power amps).
If you go that way, I would indeed recommend having 1 SMPS filter for the ACA and 1 SMPS filter for the B1K, in hope these help reducing any potential interference between the two.
The Murata Coil (Mark is everywhere LOL), dampens HF in it...self of course, but is IMHO likely to work best in conjunction with a following RC filter that has a large C. That is the case with the large caps in the Mini's PS.
That is if you use the coil alone for space reasons. Of course, as Pete suggested, there is no harm at least trying Murata coil + Mark's SMPS filter: may work or not really be better, depends I guess... but will always be functional of course.
Last but not least, I have the SMPS filter in the same housing as the B1K, and I have seen others doing it, but can't comment regarding the original casing as mine is from a third party...
I hope this helps
Claude
If you go that way, I would indeed recommend having 1 SMPS filter for the ACA and 1 SMPS filter for the B1K, in hope these help reducing any potential interference between the two.
The Murata Coil (Mark is everywhere LOL), dampens HF in it...self of course, but is IMHO likely to work best in conjunction with a following RC filter that has a large C. That is the case with the large caps in the Mini's PS.
That is if you use the coil alone for space reasons. Of course, as Pete suggested, there is no harm at least trying Murata coil + Mark's SMPS filter: may work or not really be better, depends I guess... but will always be functional of course.
Last but not least, I have the SMPS filter in the same housing as the B1K, and I have seen others doing it, but can't comment regarding the original casing as mine is from a third party...
I hope this helps
Claude
Quote: Ideally I'd like to figure out an external power supply with an IEC plug and 4 or so outputs for whatever voltages are necessary by just choosing the right resistor combo. Has anyone done an adjustable power supply with ladder or parallel resistors like used in a stepped attenuator for volume control? Not sure how much power the boards on available ones like goldpoint could handle since they're not really designed for that
=> Inded the problem is power consumption (losses, needs bigger PS!!!) and possibly also dimensioning of the parts to cope with that (board, switch, resistors). Could work for small power needs, IMHO too complicated for larger power needs... if using a linear PS, a variac in front of a big tranny is possibly easier and more efficient...
Just thinking out loud as never did that though
Claude
=> Inded the problem is power consumption (losses, needs bigger PS!!!) and possibly also dimensioning of the parts to cope with that (board, switch, resistors). Could work for small power needs, IMHO too complicated for larger power needs... if using a linear PS, a variac in front of a big tranny is possibly easier and more efficient...
Just thinking out loud as never did that though
Claude
I 3D printed a beam to mount the filter board in the Korg B1 chassis that simply slides into the rail slot on the chassis with a tight interference fit. The filter board then bolts on to that. I posted the 3D print file here. There's a bunch of pictures in the pdf I attached to a prior Post (#8,515).
Edit: Fixed link
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Bad link.... to post 8515, it should be: www.diyaudio.com/community/threads/b1-with-korg-triode.313612/post-7624845
@birdbox - That is SLICK! I have zero experience with 3d printing but know there are online places you can send the file to. So cool, the 3d printing stuff really opens up a whole world of awesome DIY options! Do you guys have any particular online 3d printers you've had good experiences with?
Regarding a "mothership" power supply - I just like the idea of not having a bunch of wall warts jammed into a power strip and thought it would be a reasonable option. Have to look into the details as I have a feeling the B1 and ACA won't be my last builds that use lower than mains voltage. It's actually a nice break from the tube stuff which always has you a little on edge when playing with 400+ volts. Always do the "one hand in my pocket" and stand on a rubber mat when poking around inside.
Regarding a "mothership" power supply - I just like the idea of not having a bunch of wall warts jammed into a power strip and thought it would be a reasonable option. Have to look into the details as I have a feeling the B1 and ACA won't be my last builds that use lower than mains voltage. It's actually a nice break from the tube stuff which always has you a little on edge when playing with 400+ volts. Always do the "one hand in my pocket" and stand on a rubber mat when poking around inside.
^ I'm happy to print a few out for you and send your way (please send me a private message if you'd like). There are also local "Makerspaces" in most communities available for a small daily fee to use the equipment. Often places like a public library, local community college, or higher school will have them available for free to use. I wouldn't recommend going to an online 3D fabrication house unless you need a large quantity. The material cost to print one of these "beams" is about 10 cents. I'll print as many beams as you want if you just cover shipping.
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