SMPS DC Filter P089ZB Kit

10⁰⁰

The PO89ZB, an inline DC filter for SMPS wall warts, preamps, HPAs, Korg NuTubes, B1, etc.

This filter is limited to single rail 48V DC, 3A applications. The kit contains top-quality parts as selected by the circuit’s designer which includes KEMET ESH477M050AH4AA or Nichicon UHW1H471MPD capacitors and top-quality Bournes inductors RLB0912-2R2ML. The kit’s PCBs are fabricated using 2oz copper and tinned thru-holes for low noise operation and ease of assembly.

Note that the kits will use either the Nichicons or Kemets depending on availability as these are often difficult to source. Both are considered the top two choices for low-ESR caps for the circuit and users will be happy using either.

For more information about the filter see the thread.

Included in this kit:

PCB
R1, R3: 0.04R or 0.05R 5% 1W precision current sense resistors, LS 12mm
R2, R4: 953ohm 1% 0.25W resistor
C1, C2: 470 uF 50V capacitor, LS 5mm and Diam 10mm
L1, L2: 2.2uH 7.5A 0.10R inductor, LS 5mm and Diam 9mm
D1: 68V Unidir TVS 600W, DO-204 pkg

Links:

The PO89ZB discussion thread on diyAudio

You are a star!

Beautiful little kit. The sound of the B1 Korg is more detailed.

Great with NuTube preamp

Sounds great with NuTube preamp and Purifi Eval1.

Wish I would have read it wasn't built

Kind of funny that I missed that part, but the packaging was great parts are sealed and on time.

PO89ZB

Was surprised how well this works, bought several, used one on my 6-24 crossover. To my ears, bass has more authority and image is more vivid . Will try the other on the Korg B1. Going to get 2 more for new projects. Highly recommended

Everything works as desired

Easy to assemble, all the necessary parts are included.
With my Meanwell LRS-75-24 SMPS I noticed a significant improvement in ripple and noise.

Great for B1 Korg Kit

Wow, talk about an easy upgrade. Took about 15 minutes to solder together and about 20 minutes to drill 2 holes and implement into the B1 Korg kit chassis. I used taller standoffs so the boards were at different levels. Otherwise it would be a very tight fit.

My B1 build is pretty simple. Standard kit but with Vishay Dale resistors, .22uf wimas as input DC blocking caps. 10uf silmics in the middle and 6.8uf clarity caps on the output caps. Whatever I had in my box. Makes for a beautiful sounding preamp.