Electronic Choke

The electronic choke (or E-choke) can replace traditional chokes. Menno van der Veen and TentLabs introduce this new module, based on novel techniques, with some advantages over traditional chokes. The module comes fully stuffed and is intended for upgrade existing tube amplifiers and for building new amplifiers.

Tentlabs E-choke

€ 57.02
€ 69.00


Designer Menno van der Veen set the concept for this DIY module. The E-choke replaces traditional chokes that generally work quite well, but suffer from some disadvantages:
• high weight
• relatively big size
• magnetic field radiation that induces hum in the circuit

The E-choke effectively solves all these issues, and offers up to 70dB supply ripple reduction at currents up to 500 mAdc. In addition, intermodulation distortion reduces dramatically,
see the measurements and background articles below.

UL40-S2, triode, distortion, power supply with only capacitors

UL40-S2, triode, distortion, power supply including E-choke

Look how effectively the choke removes the hum, but also dramatically reduces the intermodulation products of the signal (1 kHz) with power supply ripple (100 Hz)

Technical description
See the background article by Menno Vanderveen:
E-choke design (English)

• Imax out 500mAdc
• Vmax in 450Vdc
(can be adapted to 600Vdc max when changing input capacitor to suitable working voltage)
• Vripple 15Vtt (maximum input ripple)
• C-in 330uF/450V (included on module):
C-in may be reduced linearly when current consumption is lower than 500mA
C-in must be reduced when valve rectification is applied
• C-out 330uF/450V (externally required, recommended value)
• Voltage drop <17Vdc (in-out at 500mAdc load)
• Dissipation <5W
• Heatsink integrated, connected to gnd
• Rejection :
>40dB, time modus off (mostly used with class AB amplifiers)
>60dB, time modus on (recommended for class A amplifiers)
• short circuit NOT protected, always include fuse at module output

PCB size: 72*50*50 mm (W*L*H) (includes electrolytic, excludes standoffs)
Hole pitch: 63*41 mm (symmetrical). All hole diameters 3.2 mm

No manual yet, but connections are fairly straightforward, see example below:

This module is warranted for 5 years, assumed all mounting instructions are followed