The LM317, a very convenient monolithic regulator, has been around for many decades and is used in a multitude of applications in millions of items of equipment.
Naim Audio are users of this device in bulk quantities and as such, the little LM317 does a fine job of regulating the DC lines in virtually all the products produced by them.
image Avondale Audio tracking pre regulator
In the light of ongoing development though, just tacking a 317 onto a capacitor smoothed DC line is not nearly good enough if you wish to extract the very best from your preamplifier, CD player or other low level equipment.
The LM317 is fine for run of the mill regulation but there still remains quite an amount of noise at the output and the frequency response over the audio spectrum leaves much to be desired.
There are many and various alternatives on the market such as the Walt Jung regulator system, however, the sheer size of the assembly means it can't be accommodated into every item of equipment.
- Beginning with the principle that 'simple is best' the Voltage Locked TPR Tracking Pre regulator stands out as neat an implementation of the LM317 as there has ever been and with the following features:
- Small in size only 47mm X 44mm footprint. This may be introduced into a variety of equipment without the need for any further voltage requirements.
- The use of the tracking pre regulator system means that rejection of any incoming aberrations in the supply line is improved by a factor of as much as 8 times over the simple, single 317 circuit.
- By designing in a few carefully chosen components, the deceptively simple TPR circuit delivers all that could be desired across the audio spectrum.
- Ideal for replacement of the 317 system as fitted into the early Snaps power supply with an amazing hike in perceived performance.
- User friendly in the building of virtually any low level power supply for use with high end audio equipment.