***sale***Tentlabs: XO2 (XO + low noise supply PCB) mhz.xxx: 11, 16, 24, 27, 33, 45

Tentlabs shunt regulators are designed to upgrade power supplies of both analog and digital circuits, mostly found in CD/DVD players, DACs and similar audio equipment. Substituting, or adding these regulators enhances the sound quality in terms of transparency and resolution, at reasonable price. Connections in general are easilly made. This type of upgrade requires little knowledge of electronics hence is accessible for every enthousiastic audiophile DIY.

Please indicate required voltage: 3v3, 5v, 15v, -15v

Tentlabs: 2.5A unit - adjustable on board 1.5v to 12.6v, input voltage should not exceed 1v above spec.
Total size 50*90*40mm (W*L*H, heatsink included, standoffs excluded).
Weight each 90 gram (excluding packaging)
Hole pitch 41* 77mm.
Needs 5mm stand-offs to mount on chassis, supplied with modules. Standard version, output currents up to 2.5A. These typically serve small and medium size triodes up to output tubes like 300b and 2A3, and have an integrated heatsink.

Tentlabs: 5A unit - adjustable on board 1.5v to 12.6v, input voltage should not exceed 1v above spec.
Total size 50*90*90mm (W*L*H, heatsink included).
Weight 375 gram (excluding packaging).
Needs M4 bolts to mount on chassis, not supplied with modules. Output currents up to 5A. These will suit the beefy types like 211, 813, 845 and SV572 and have a bigger heatsink.

TentLabs Directly Heated Tubes Supply

Despite their massive linearity, Directly Heated Tubes (DHTs) have one major disadvantage. Their heater is part of the signal flow, i.e. is included in the audio path, hence the heater supply is affecting the sound.

TentLabs now introduces a novel heater module, based on traditional techniques, but with some major advantages over existing solutions. Read further!

Purpose

TentLabs heater supply is designed to heat DHT's the cleanest way possible, without affecting the music currents generated inside the tubes' heater. The supplies generate a very low noise output, while maintaining its' high output impedance. Result areas are:
Bigger soundstage
Better focus
Cleaner tone
Better resolution

Existing current supplies lack true high output impedance and need adjustment during use. This new module is truly different in many areas - read on !

Technology

TentLabs has investigated to effect of the heater supply in Directly Heated Tubes. For detailed information and a rationale for the use of current heating, see the presentation on heater supplies for DHTs.

An overview of the TentLabs supply is shown below:

The current source maintains the high output impedance (typically > 10kOhm), whereas the voltage control takes away the need to trim the output voltage after instalment, or during use. The accurate reference guarantees long term stability, and contributes to a clean output current. The module exactly supplies that amount of heater current, until the required DC voltage is achieved, e.g. 5V for a 300b.

The rectifying bridge consists of low noise Schottky Barier diodes and Electrolytic capacitors (a total of about 20.000uF) with a well chosen amount of ESR, to dampen and reduce the current peaks - all contributes to low noise output !

Application

A typical example is shown below:

Each tube needs its own heater supply, fed by a separate winding from the power transformer. The whole supply then is floating, and only has one connection to ground, as shown above. This example above shows the DHT in fixed bias mode. When using cathode bias, the grounded leg has to be connected to the top of the cathode resistor.

These are the only connections, so no caps, no hum-bucking pot, no nada!

The total output current is limited to some 2,5A to 5A, depending on the version, so slow start-up is the result. Especially when the tube is cold, this is a nice feature. Cold tubes, when heated with traditional supplies, draw currents up to ten times their nominal current. Using TentLabs heater supply will gently switch on your tubes.

Only at installation, the supply needs minor DC adjustment, to compensate for any voltage losses in the wiring (some 100 mV are easily lost at these current ratings). During use, no adjustments are needed anymore, not even after changing the tubes !

Specifications

Electrical

All voltages available between 1.5V and 12.6V, please specify when ordering.
Output current: automatically adapts to required level to reach voltage specified above.
Input voltage should not exceed 1 V above specification (see application info).
Output noise < 1 mVrms (1 Hz - 1 MHz).
Output noise < 200 uVpeak at 100Hz / 120Hz.
Output impedance 10 mOhm at 0Hz.
Output impedance 10kOhm > 5Hz.
Heater: The heatsink is electrically isolated from the circuit and can be attached to a chassis

Notes
The unit will not work without output load, a minimum of 200mA is required
The output is not short circuit proof

Available versions

Currently 2 hardware versions are available
Output currents up to 2.5A. These typically serve small and medium size triodes up to output tubes like 300b and 2A3, and have an integrated heatsink.
Output currents up to 5A. These will suit the beefy types like 211, 813, 845 and SV572 and have a bigger heatsink.

Mechanical

2.5A unit
Total size 50*90*40mm (W*L*H, heatsink included, standoffs excluded).
Weight each 90 gram (excluding packaging)
Hole pitch 41* 77mm.
Needs 5mm stand-offs to mount on chassis, supplied with modules.

5A unit
Total size 50*90*90mm (W*L*H, heatsink included).
Weight 375 gram (excluding packaging).
Needs M4 bolts to mount on chassis, not supplied with modules.

Warrantee

Single units can be ordered. 5 years of warrantee is valid for the heater supplies, assumed they are build in according application information.

Mounting

Look at the support page for detailed mounting instructions.

Support

As this is a true DIY product, so no additional support can be given, other than already available at the TENTlabs website.

Safety

Though this is a product which if handled properly is save, it is surrounded by high voltages. Working with high voltages requires safety measures and professional behavior. Tentlabs takes NO responsibility for accidents resulting from improper usage or handling.

© Copyright 2004 TentLabs