Low DCR Low Inductance Filter Chokes

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Filter Chokes For Low DCR SE Amplifers

I provide a list of chokes suitable for building Low DCR SE amplifiers using LCLC power supply filters. Most of these I own and have personally used myself in SE amplifier circuits.

Edcor XC 87

Specs : 2H / 300mA / 21 ohms. This choke is suitable for the L2 position in a "flywheel" filter.  I have used this part in circuits up to 500VDC.  The DCR of 21 ohms is borderline mid to high fidelity.

Hammond 159ZA

Specs : 300mH / 1A / 6 ohms.  This part was recommended to me by Jeff Medwin aka Drlowmu for use in LSES filters in the L1 & L2 position.  The DCR of 6 ohms is considered ultra high fidelity. I have not personally used this part but I do own (2) samples. I will report any end user experiences I have with this part at a later time.

Medwin-Heyboer HTS-10100

Specs : 2H / 300mA / 7 ohms. This part was built by Heyboer as specified by Jeff Medwin aka Drlowmu for the L2 position in "flywheel" filters. The part has parallel lead out wires of Kimber TCCS for optimized transfer efficiency. The DCR of 7 ohms is considered ultra high fidelity.

Triad C-40X and Stancor C-2708

Specs : 320mH / 600mA / 10 ohms . This part was recommended by Jeff Medwin aka Drlowmu for use in LSES filters in the L1 & L2 position.  He thought that this part would have similar performance attributes to the Stancor C-2708 filter chokes that Dennis Fraker apparently uses in his Serious Stereo SE DC 2A3 amplifiers.  I thought that this suggestion was reasonable and purchased (6) units for  low DCR filter experiments. I found the C-40X to have a mechanical buzz at low currents  (60-65mA) in a SE RC 6AQ5 stereo circuit, so I can't personally recommend this part for L1 duties.  

I have used the Triad C-40X in the L2 & L3 position in various low DCR filter circuits with some success. 


The Stancor C-2708 has the same specs as the Triad C-40X, but is reported not to suffer from  mechanical buzzing issues when used in the L1 position in LSES filters at low-moderate DC currents. I have not personally used this part or know if current production Stancor C-2708 chokes deliver the same performance as the older production models.  

Triad C-56U

Specs : 35mH / 2A / .79ohms. This part was recommended by Jeff Medwin aka Drlowmu for use in "flywheel" filters in the L1 position.   Excellent part .  I have used it up to 500VDC off a solid state rectifier and up to 120-140mADC before with no mechanical buzzing issues.