RS Components. In the UK.
Here you go: https://uk.rs-online.com/web/p/through-hole-resistors/4879131
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I built one of these kits and have some questions. I have it to filter from a 24 volt 3.75 amp smps that powers an old realistic phono pre amp . Without the filter the supply is fairly "quiet" except I get noise around 730 Hz that is annoying and I'd like to get rid of it.With the filter it just lowers that by 2 db. I also have some 60 hz and 120 hz noise and it lowers that by about 2 db. So I got a new 24 volt 1 amp regular transformer style supply and with that powering the pre amp (without the filter) I get pretty loud 120 Hz hum. Then when I put the filter in the chain I get nothing.It's like the pre amp isn't getting power. I can unplug that supply and plug in the smps to the filter and it works,but unplug that and plug in the tranformer supply and nothing. Is there a reason why this is happening? also ,for the people that know phono pre amps,are there any that are "quiet". I'm going from phono preamp into a zoom handy recorder H2 and have pretty much everything else in the room turned off. I'd like to just find a phono pre amp that is "quiet" I have used the phono input of my old onkyo receiver and that is pretty quiet but one channel is about 5 db higher than the other when I record silence. I'm just trying to digitize some of my old records because the newer cd versions (if I can get them,seem very loud to me,I don't know if they just record them loud or add more compression or something but I don't like that.
Basicly,can this filter be used with a transformer style supply?
Basicly,can this filter be used with a transformer style supply?
@jsdspif
Yes, you can use this filter with a transformer style supply, it will certainly help clean up PSU noise, but it’s not going to have anywhere as much benefit as when used with a switcher, as the noise generated by a smps is very different from the noise generated by a linear.
As for the things you are describing with your recording setup, those are issues not related to PSU filtering. Yes, there are lots of phono preamps that are quiet, there is something not right with yours.
Yes, you can use this filter with a transformer style supply, it will certainly help clean up PSU noise, but it’s not going to have anywhere as much benefit as when used with a switcher, as the noise generated by a smps is very different from the noise generated by a linear.
As for the things you are describing with your recording setup, those are issues not related to PSU filtering. Yes, there are lots of phono preamps that are quiet, there is something not right with yours.
As many of you already know I built over a dozen of these marvelous SMPS filters and I try them in different set ups, often having to leave the unit at friend's because they don't want to take it out again. I have yet to find a situation, within its application field, where it didn't shine.
And yet I found another use for it.
I had already spectacular results putting this filter between the SMPS and a D50S DAC, resulting in an average DAC becoming listenable and enjoyable.
I have a secondary set up with Raspberry 2b/Voluminio with a very basic Hat DAC (Zero), excellent VFET amp and VG Klipsch RP-8000F LS angled as they should. Clearly the source is basic but most family members here are happy having music at a touch of their smartphone in the living room, instead of waiting for me to put a record or play a CD in the proper listening room, so the average source has to stay.
I was quite amazed by the good balance of the sound of this basic DAC, although lacking quite a few bits to my ears when listening to it. In terms of PS the hat DAC is fed directly by the Pi (ouch), which itself is a mini computer fed by a basic SMPS. Hey, is there really nothing I can do but purchase a better hat DAC or even output card to feed a proper DAC to improve the sound? Of course: I could still try feeding it with a linear PS... or, as space and form factor are also an issue, the existing SMPS with mark's excellent filter.
On the other hand, whatever I do at PS stage, it will still be shared between Pi and this hat DAC. Worth a try I thought, so I purchased for 2$ some DC Jack to USB Mini converter plugs to enable quick tries with and without Mark's SMPS filter... without even to have to butcher my existing connection cables of the said filter.
What can I say? For less than 10$ part's cost (filter and plugs) it has improved the sound immensely, to make it even acceptable to my ears. I am not in a hurry anymore to change the sound card, although I may one day, just to play with it. As for the D50S, with a similar magnitude, the sound as improved a lot in the bass department (clearly plays deeper tones, while less burble in the upper bass), music sounds crispier up to the treble, notes last longer / are more realistic and the imaging is less flat / more 3D.
I have also tried a good quality SMPS with low ripple, and an average SMPS, and both benefited from the filter, resulting in the same result at the end. Basicaly through various tests I did, Mark's filter made an excellent PS out of nearly every high- to OK-quality wallwart SMPS, easily matching my big costly lab Linear PS (when paired with small components).
Bottom line: if you listen to musicwith a Raspberry Pi through a hat dac with a SMPS feeding it, I urge you to try Mark's excellent filter between your SMPS and your unit. You are likely to lift your sound quality significantly for the cost of a few coffees while having some DIY fun, and the filter is so small that you won't ruin your form factor.
Have fun
Claude (who has yet to find an application where this filter fails!)
And yet I found another use for it.
I had already spectacular results putting this filter between the SMPS and a D50S DAC, resulting in an average DAC becoming listenable and enjoyable.
I have a secondary set up with Raspberry 2b/Voluminio with a very basic Hat DAC (Zero), excellent VFET amp and VG Klipsch RP-8000F LS angled as they should. Clearly the source is basic but most family members here are happy having music at a touch of their smartphone in the living room, instead of waiting for me to put a record or play a CD in the proper listening room, so the average source has to stay.
I was quite amazed by the good balance of the sound of this basic DAC, although lacking quite a few bits to my ears when listening to it. In terms of PS the hat DAC is fed directly by the Pi (ouch), which itself is a mini computer fed by a basic SMPS. Hey, is there really nothing I can do but purchase a better hat DAC or even output card to feed a proper DAC to improve the sound? Of course: I could still try feeding it with a linear PS... or, as space and form factor are also an issue, the existing SMPS with mark's excellent filter.
On the other hand, whatever I do at PS stage, it will still be shared between Pi and this hat DAC. Worth a try I thought, so I purchased for 2$ some DC Jack to USB Mini converter plugs to enable quick tries with and without Mark's SMPS filter... without even to have to butcher my existing connection cables of the said filter.
What can I say? For less than 10$ part's cost (filter and plugs) it has improved the sound immensely, to make it even acceptable to my ears. I am not in a hurry anymore to change the sound card, although I may one day, just to play with it. As for the D50S, with a similar magnitude, the sound as improved a lot in the bass department (clearly plays deeper tones, while less burble in the upper bass), music sounds crispier up to the treble, notes last longer / are more realistic and the imaging is less flat / more 3D.
I have also tried a good quality SMPS with low ripple, and an average SMPS, and both benefited from the filter, resulting in the same result at the end. Basicaly through various tests I did, Mark's filter made an excellent PS out of nearly every high- to OK-quality wallwart SMPS, easily matching my big costly lab Linear PS (when paired with small components).
Bottom line: if you listen to musicwith a Raspberry Pi through a hat dac with a SMPS feeding it, I urge you to try Mark's excellent filter between your SMPS and your unit. You are likely to lift your sound quality significantly for the cost of a few coffees while having some DIY fun, and the filter is so small that you won't ruin your form factor.
Have fun
Claude (who has yet to find an application where this filter fails!)
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I just finished a pair of these filters. Boy they are tiny! I am planning to use these on my ACA 1.8 mono blocks that I built in 2020. At the moment I am awaiting for the arrival of the power jacks from Amazon so I can do a build similar to Audiobear in post #935, although I have some thin plywood that I will utilize instead of what others have built. If they improve the sound as documented above I plan to see if I can fit them into the ACA cabinets.
I'm not sure about whether it's even worth mentioning, but there was recently a GB for custommade ACA-powersupply-filter-kits for the ACA, much beefier than thePO89ZB...
FWIW...
(edit: PO89ZB is of course suited even for good ol' ACA!
)
((Edit-edit: Not so sure about whether you can use it for an ACA — which is said to draw up to 5A!))
FWIW...
(edit: PO89ZB is of course suited even for good ol' ACA!
)((Edit-edit: Not so sure about whether you can use it for an ACA — which is said to draw up to 5A!))
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Ah there it is. Everyone was talking 1.45A, but then suddenly the 5A emerged out of nowhere. Pardon me.
I wasn’t aware of a custom made Filter for the ACAs. I ordered the P089ZBs when I first purchased the Sony JFET kits in July ‘22, but I changed my mind and purchased the Mark Johnson designed PS Filters to use in the JFET. So I will use these extra boards to try out for the ACAs. Fun stuff….
Here is what I ended up doing with the P089ZB and the ACA V1.8 with premium parts and a single 24V power supply. Because the P089ZB is passive it took .2 volts of power. The "In" voltage was 24.7 and "out" voltage was 24.5 from the P089ZB . The only mod I did to the P089ZB was to use the Nichicon 470uF 50V caps instead of the stock caps.
It was a fairly easy mod, the P089ZB boards and parts are only a few bucks apiece. And the improvement was subtle but there. The sound was cleaner and less processed sounding, not sure how else to describe it.
It was a fairly easy mod, the P089ZB boards and parts are only a few bucks apiece. And the improvement was subtle but there. The sound was cleaner and less processed sounding, not sure how else to describe it.
From amazon, I buy 99% isopropyl alcohol (sales link) and also a very cheap electric toothbrush (link 2) . Then I follow this procedure
Working over the laundry room sink & wearing nitrile disposable gloves: flood PCB with 99% IPA, scrub vigorously with electric toothbrush
Flood PCB again to rinse. Gently shake board into sink.
Repeat the above two steps again.
Apply 1 Tbsp (15 ml) liquid dish soap (Joy, Dawn, Palmolive, Persil) a/k/a "washing up liquid" to PCB, and scrub vigorously.
Rinse very very VERY thoroughly under running water for at least 30 seconds. You don't want even one molecule of dish soap left behind.
Flood PCB with 99% IPA to rinse and more importantly, to flush away all traces of water. Gently shake board into sink.
Flood PCB again with 99% IPA for final rinse
Use pistol style hair dryer to quickly blast away IPA and dry the board. Alternate between hot and cold air to avoid burning your fingers.