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Gold Fuse
Frequently Asked questions about the AMR Gold Fuse
With an AMR Gold Fuse and once it has fully burned-in, the listener should notice the music produced by the audio component take on a fuller body, better definition and detail, with reduced distortion and an extended dynamic range.

For a visual component such as an LCD television or a Blu-Ray player, the picture and sound quality should be somewhat sharper and crisper. The audio/visual texture and colour should be richer with an overall more dynamic presentation.

At present, there are 7 different values: 0.125A / 0.25A / 0.5A / 1A / 2A / 5A / 10A which represent the main spectrum of amperage rating for audio/visual equipment.

A further 5 different values: 1.6A / 3.15A / 6.3A / 8A / 15A will be added in the near future.

Please contact your local AMR distributor/dealer or AMR directly for further information.

By examining the current fuse, check both end caps. One of the end caps will have a stamped value such as “0.5A”. Simply look up the same or nearest but lower fuse value from the AMR range and replace with this fuse.

Presently, 5 x 20mm is available for internal component use and/or the IEC connector at the rear of the component. This size is commonplace in European equipment.

In the near future, 6.3 x 32mm which is popular in US equipment and the 6.4 x 25mm fuse which is mainly suited to UK mains electrical systems, will also become available.

AMR recommends the use of slow-blow fuses for fusing any mains circuit. Such slow-blow fuses require a sustained period of excessive current draw to blow which only arises in excessive/overload situations rather than possibly arising just on power-on.

Mains Fuses are generally fitted to make sure the equipment is disconnected from the mains in case of a severe defect, such as in internal short, to ensure mainly fire-safety and to protect the mains network. That is the reason why fuses are mandatory and should not be bypassed.

As a rule, fuses in equipment are not fitted or required to protect the equipment. Even fast-blow fuses are far too slow to protect semiconductors from damage and slow-blow fuses usually suffice to protect valves.

If a manufacturer fits and has specified fast-blow fuses, they may very well have a reason, so in this case we do not recommend AMR Fuses. At the same time if slow-blow fuses are specified or fitted they should not replaced with fast-blow fuses. When used as the main mains fuse, the "inrush"currents during switch on usually will blow out a correctly-sized fast-blow fuse with a few dozen switch on cycles, while a correctly sized slow-blow fuse will survive almost indefinitely.

AMR recommends critical listening after 24-hours of use.
Typical industrial grade fuses last for many years if the electricity that passes through does not stray above the designed tolerance.

Given the much higher quality of construction of the AMR Gold Fuse, if the electricity that passes through is within designed parameters, we estimate the life span should be for many, many years to come.

Pure silver is a very soft metal (think of a pure silver necklace which is very fragile) hence it is not applicable to make the fuse wire itself or the end-caps from pure silver.

Where possible, AMR has used silver to make the fuse wire from a silver alloy. The fuse wire is designed to operate as a safety element and melt at the rated amperage. Pure silver cannot perform this duty accurately and across a range of electrical ratings hence, the AMR Fuse is the next best approach, being made of a silver alloy.

Silver will oxidise which reduces long-term reliability and performance so the end caps are gold-plated instead of silver-plated. The plating is over copper as again, pure silver is too soft for this task.

The AMR Gold Fuse is a dedicated reference design to improve each and every audio and visual component. From the market research undertaken by AMR, we found that customers wished to upgrade an audio component at a time and as such, typically holds more than 1, and most probably up to 3 fuses.

Therefore, AMR decided to offer its range of fuses in a 3-pack to ensure that any component may be fully upgraded with an AMR Fuse. This stance has established the AMR Gold Fuse as second-to-none in terms of maximum performance and unsurpassed value for money.

In recent times, although many music formats (including WAV, AAC, WMA, MP3 etc.) have become computer-based, the sound system of most computers however, leaves much to be desired.

The USB input of the CD-77 allows its superior digital-to-analogue conversion and analogue stage to be used in the replay of computer-based music formats to the same level of quality provided by the CD-77 for compact discs. (please refer to OptiBus® in the Advanced Design Features section for more details)

CD is an optical format. The presence of varying external light conditions such as that admitted by a transparent lid was found detrimental to the sonic performance.
Virtually all CD Recordings are made for speaker replay. Thus reproducing said recordings via headphones is neither satisfying nor realistic. In order to improve the situation somewhat, a significant amount of analogue or digital processing is essential.

AMR feel that the inclusion of these would have exceeded the design remit for a CD source and is better placed in a dedicated headphone amplifier which includes the required processing. Such properly executed headphone amplifiers are readily available from specialist manufacturers.

The CD-77 uses a completely signal-ended signal path as we have found this to give a more realistic reproduction of music. However, in terms of sound quality, we found the XLR connector preferable to the RCA connector, even when used with un-balanced signals.

Consequently, we have offered the XLR output in a manner that is fully compatible with balanced equipment: takes full advantage of balanced connections yet retains the desirable single ended signal circuit.

Between different recordings usually, the techniques used to record as well as those used to master the recordings differ: as do the skills and aims of recording engineers and producers.

Therefore, it is very unlikely that two CDs recorded and produced by different engineers and producers will sound identical. Some engineers and producers are better able to achieve high sound quality recordings than others.

AMR is an uncompromising audio company and one of the remaining areas in our products that we felt we could improve upon, was the fuse as this is typically, an industrial-grade item which does not satisfy the needs of the enthusiast. Hence, the AMR Gold Fuse was developed to specifically address this aspect.
Please refer to the AMR Gold Fuse product and features pages for an overview of a standard industrial grade fuse and a detailed explanation of the AMR Gold Fuse.
The UK-sized fuse replaces the standard UK fuse inside the UK 3-pin type main plug.

With the EU and US-sized fuses, they are located in the IEC of the component which is found at the rear, just above/below where the mains cable is inserted.

With a small minority of components, the fuse may be fitted to the inside of the component. In such cases, please consult a qualified electrician before attempting to access the inside to replace the fuse.
Most audio equipment due to the surge on power up require slow-blow.
However, for certain products such as speakers, then the fast-blow type is better-suited. The AMR 2.5A and 4A fast-blow fuses were developed specifically for this application. In particular, they ideally-suit the Magnepan range of speakers.
 
   
   


     
 
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