PO89ZB , an inline DC filter for SMPS wall warts . Preamps, HPA, Korg NuTube, etc - Page 33

SuppersReady · 17th January 2021, 03:23 PM

I've been having fun today trying them out with my ACP+ and Grado 325s. You can hear a difference with one in circuit. The difference with two is even better. Lots and lots of extra musical details. Spatial positioning of instruments is truly excellent. Now I just need to get a case and then try it through my main system.

Second opinion from SWMBO, "It's like putting your glasses on, it brings things into focus."

This afternoon's project is to try them out on the Starving Student II and, if time allows, the B1K in the office system.

I hope that you all enjoy them too.

1883 · 17th January 2021, 04:50 PM

Pictures please.

konst · 17th January 2021, 05:42 PM

Last night I tried the Salas UBiB regulator on my B1Korg, the benefits of hte PO89ZB are very much evident even with that low noise regulator. The measurable (with my skills) difference in noise seems to be very small, yet it realy does work even there

Fast Eddie D · 17th January 2021, 06:31 PM

This is very interesting. I tried to make a filter like this with inductors I pulled out of a switching power supply. It did attenuate the noise, but not nearly enough. It made a slight improvement but the headphone amp clearly sounded better with an old fashioned wall wart powering it.

I was wondering if the circuit could be scaled. For line level circuits and class AB headphone amps I was thinking of using 0.4 ohm or 1 ohm series resistors. It sure would be handy to use some of these laptop supplies for audio projects.

Inductors out of stock https://www.mouser.com/ProductDetail...BdHMSEZA%3D%3D but they're affordable and not too big.

Monk55 · 17th January 2021, 08:46 PM

Completed 24v supply for Korg B1. Filter in the corner.

Mark Johnson · 17th January 2021, 10:16 PM

Lovely build, @Monk55! Wasn't expecting to see a 200 watt SMPS (140 watts without fan) in there.

SuppersReady · 10:26 PM

Since you asked 1883,

Not pretty, but easy enough to do.

It allows me to try it on any of my preamps.

1883 · 17th January 2021, 10:29 PM

Thank You

Monk55 · 02:13 PM

Just about as small as can go...
Boxes:

LeMotech 5 Pieces Plastic Project Box es Junction Case for Electronic Project, Black 3.15 x 1.97 x 1.02 inch (80 x 50x 26 mm)

Jack’s:
5.5 x 2.1 MM 10A DC Power Jack Socket Dc099 30V Threaded Female Mount Connector Adapter with 3.94 Ich 18AWG Cable and DC Barrel Jack Plug Male Lsgoodcare

Siliconed board to box.

kasey197 · 18th January 2021, 02:31 PM

These are awesome ! I also enjoyed the company of a super simple (standard 5 component) cap multiplier after the passive filter ... just sayin

17th January 2021, 03:23 PM	#321
SuppersReady diyAudio Member Join Date: Oct 2002 Location: UK	I've been having fun today trying them out with my ACP+ and Grado 325s. You can hear a difference with one in circuit. The difference with two is even better. Lots and lots of extra musical details. Spatial positioning of instruments is truly excellent. Now I just need to get a case and then try it through my main system. Second opinion from SWMBO, "It's like putting your glasses on, it brings things into focus." This afternoon's project is to try them out on the Starving Student II and, if time allows, the B1K in the office system. I hope that you all enjoy them too. __________________ A poor life this if, full of care We have no time to stand and stare.

17th January 2021, 04:50 PM	#322
1883 diyAudio Member Join Date: Dec 2017	Pictures please Pictures please.

17th January 2021, 10:29 PM	#328
1883 diyAudio Member Join Date: Dec 2017	Thank You Thank You

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Korg NuTube B1 guide	6L6	Pass Labs	8	14th October 2020 07:59 AM
Korg Nutube B1 Pre-Order Q&A	Jason	The diyAudio Store	33	14th October 2020 07:55 AM
Korg Nutube	pmoyle111	Tubes / Valves	6	24th April 2020 11:41 PM
Korg NuTube is now available online	pmillett	Vendor's Bazaar	156	24th December 2019 12:33 AM
WTB: Firstwatt Korg Nutube B1 (or just PCB)	Brzzl	Swap Meet	2	4th September 2019 10:54 AM

New To Site?	Need Help?
Register to Participate Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

17th January 2021, 06:31 PM	#324
Fast Eddie D diyAudio Member Join Date: May 2010 Location: Skokie Il	This is very interesting. I tried to make a filter like this with inductors I pulled out of a switching power supply. It did attenuate the noise, but not nearly enough. It made a slight improvement but the headphone amp clearly sounded better with an old fashioned wall wart powering it. I was wondering if the circuit could be scaled. For line level circuits and class AB headphone amps I was thinking of using 0.4 ohm or 1 ohm series resistors. It sure would be handy to use some of these laptop supplies for audio projects. Inductors out of stock https://www.mouser.com/ProductDetail...BdHMSEZA%3D%3D but they're affordable and not too big.

17th January 2021, 10:16 PM	#326
Mark Johnson diyAudio Donor diyAudio Member Join Date: May 2011 Location: Silicon Valley	Lovely build, @Monk55! Wasn't expecting to see a 200 watt SMPS (140 watts without fan) in there.

18th January 2021, 02:31 PM	#330
kasey197 The Dastardly Dad of Three diyAudio Member Join Date: Sep 2009	These are awesome ! I also enjoyed the company of a super simple (standard 5 component) cap multiplier after the passive filter ... just sayin