DNM Products - Capacitors (overview)

DNM "Guided Current" Capacitors (overview)

On this Page : GC 2T (Slit-Foil) GC 4TTN (T-Network)

It is a well-known fact in the audio industry that capacitors make a big difference to the sound quality of an amplifier, but few people have spent much time researching the reasons why.

In essence, a capacitor is two large plates of conductive material, separated by an insulator. As the charge in one plate rises, it transfers across the electrolyte to the other plate and an ac current flows.

Electrolytic capacitors are electro-chemical devices and their internal chemistry prevents the use of low resistance material like copper.

So aluminium conductors with a higher resistance must be used and this makes the capacitor's internal design quite critical for audio applications. Also, capacitors are like batteries in that they have a limited operating life depending on the quality of their materials and their running temperature - a higher temperature gives a shorter life.

Makers of quality audio amplifiers should never cut costs on the capacitors as it drastically shortens the useful life of the amplifier.

Guided Current 2T (Slit-foil) Capacitors
A major improvement in audio capacitor performance came in 1984 with a DNM invention, the slit foil capacitor.

Cut-away view of Guided Current 2T (Slit-foil) capacitor

Conventional capacitors, being made of large, coiled, thin strips of aluminium, are prone to induce eddy currents across their conducting surface. These currents prevent the capacitor from doing its job optimally, thus degrading subjective sound quality. By introducing a series of tiny slits in the foil conductors these eddy currents are dramatically reduced, so improving the subjective and measured performance.

The slit foil capacitor is made exclusively by SuperTech and it is now used in quality hi-fi products the world over.

Guided Current 4TTN (T-Network) - the world's Best Audio Electrolytic Capacitor

T-Network Capacitors, photo

The Guided Current 4TTN (T-Network) capacitor originally evolved because DNM Design required reservoirs that behaved only as capacitors, without unwanted effects such as stray resistance, inductance and eddy current generation caused by the presence of two vast conducting surfaces in the circuit.

DNM Design, in association with SuperTech, developed the Guided Current 4TTN (T-Network) capacitor to minimise these unwanted effects. Instead of the single positive and negative terminals found on two terminal capacitors, the Guided Current 4TTN (T-Network) has 2 inputs and 2 outputs.

These extra terminals are connected in a T pattern at the centre and ends of each capacitor plate, guiding the plate current along a controlled path. The Guided Current 4TTN (T-Network) design reduces the effect of unwanted resistance and inductance and the technology is combined with slit foil plates to eliminate eddy currents.

These capacitors are an order of magnitude better than normal 2 terminal ones and they transform the performance of linear and switching audio amplifiers.

Improved Capacitor Performance

Graph showing Guided Current 4TTN (T-Network) capacitors improved filtering

Graph showing Guided Current 4TTN (T-Network) capacitors improved filtering

In tests under load, the 4TTN capacitor's ability to attenuate is 11dB better than a two terminal capacitor and this extra performance is maintained up to extremely high frequencies

Subjectively, the performance of the Guided Current 4TTN (T-Network) is absolutely unparalleled - it transforms the sound of even the best amplifiers.

Objectively, Guided Current 4TTN (T-Network) capacitors improve the measured high-frequency filtering by reducing the source impedance of the power supply. The high frequency advantage offered by the Guided Current 4TTN (T-Network) has additional benefits for manufacturers trying to comply with EMC regulations.

Equivalent Circuits
Conventional Capacitor, equivalent circuit diagram

Conventional Capacitor, equivalent circuit diagram

Conventional reservoir capacitors share the input and output current pathways generating voltage spikes from the charging current as it mixes with outgoing load current in the aluminium conductors.

This is a major limitation for an audio amplifier.

T-Network Capacitor, equivalent circuit diagram

T-Network Capacitor, equivalent circuit diagram

The advanced circuit design of the new Guided Current 4TTN (T Network) Capacitor (4TTN) uses four terminals to separate the input and output currents through the whole current pathway. They remain separate so the residual resistance and inductance are less critical.

Significantly most unwanted characteristics appear on each side of the 4TTN's bulk capacitance causing the capacitor to filter even more intensively.

Circuit diagram for use of 4TTN capacitors in dual-rail and single-rail circuits (shown in a new window)

The advanced circuit design of the 4TTN and 2T plates combine today's two most advanced capacitor technologies to produce the ultimate audio capacitor.

DNM Design hold stocks of Guided Current 4TTN (T-Network) Capacitors for quick access to this technology. For OEM and retail enquiries, to Denis Morecroft.

DNM Design stock the 4 terminal Guided Current 4TTN (T-Network) capacitor in these values and voltages :-
10,000 µF 63 Volt values
10,000 µF 100 Volt values - these are out of stock but on order.

Case size information and data sheets will be added here shortly.

You can either use our Online Shop
or post details of your order with a sterling cheque or bankers draft to DNM Design at :
18, Hartford Road,
Huntingdon,
Cambridgeshire PE29 3QD,
United Kingdom.

DNM Design also stock the 2 terminal Slit Foil capacitors in these values and voltages :-

10,000 µF 80 Volt 2 pin Snap-In mount. Case size information and data is here.

Production enquiries for Guided Current 4TTN (T-Network) and Guided Current 2T (Slit Foil) capacitors are particularly welcome.
Production orders of 1000 pieces or more can be custom designed in capacitance sizes and voltages dedicated to the amplifier including custom sleeving and printing.
Where required, technical assistance is available from DNM Design. For all T-Network and Slit Foil enquiries for details.)

Manufacturer :

SuperTech

<< Previous
Cables

Next >>
Technical Specifications

	© DNM Design 2018 (Legal & Credits)
	>Products<	Contacts	Principles