Restoration repair modification

The topic has often been discussed, but rarely defined exactly: what exactly is the difference between restoration, repair and modification?

Restoration means restoring a working CD player to its original state. If he does not play due to a defect, it is a repair. To the necessary measures of a restoration, which leave the original state, nevertheless naturally very time-consuming, belongs for example the elimination of cold solder joints. This is done by expert, careful desoldering and attaching new silver solder. The boards are cleaned, freed of sticky dust, animal hair and nicotine deposits. Mechanical parts are made feasible by adjusting them, adjusting them to the nearest millimeter and (possibly) lubricating them with suitable means. The list of the important steps of a faithful restoration can be continued indefinitely.

But even the replacement of aged components in a CD player blurs the line between restoration and modification. For example, capacitors are affected by aging. Many of the original types used in previous devices are no longer available for good reasons. The component market has long since replaced them with significantly improved capacitors.

To clarify the differences between restoration and modification, a comparison with cars is helpful. In classic cars, it is frowned upon to replace old parts with new ones. Subsequent built disc brakes, a power-assisted steering, even a non-original rearview mirror are considered a taboo break. The highest law is to get the car in its original state.

For a CD player, the question is different: may the old, long-dried condensers be replaced? Or does the owner want to live with a device whose sound audibly deteriorates from year to year compared to the original state? The question is more theoretical. To leave a valuable CD player with only partially functional components convulsively in its original state would mean that it is dawning on its certain death.

lifetime of electrolytic capacitors in Philips CDP

Everything speaks in favor of replacing old ones with modern components, in order to at least bring the original sound characteristics back to their original level. So here is the point where "restoration" and "modification" inevitably merge. The preliminary conclusion of this consideration is: Who wants to preserve the priceless merits of a previous CD player (they begin with the built for eternity drives and end with the extremely solid, almost vibration-free mechanics) by the use of modern components and make good use of, comes on a modification is not over.


Replacing the dried electrolytic capacitors, reworking known ground loops in power supplies, renewing old solder joints ... For all CD players with CDM 0 or CDM 1 laser unit from Revox, Philips, Marantz, Grundig or B & O. A non oversampling is included on request.
The revision of the CDM laser is not included here.

Excerpt from the works Revision

Revision standard, 230 Euro

Revision CDM Laser

The electrical and mechanical revision of the laser and the CD feeder. The subsequent adjustment and electrical calibration of the laser optics. For all CD players with CDM 0 or CDM 1 laser unit.

Excerpt from the works CDM

Revision CDM Laser, 160 Euro

Restoration metronom

Your sent CD player becomes a completely restored metronom: CD metronom

Suitable devices

Restoration metronom, 1400 Euro

Please pack your CD player like this

1. Please attach a stamped and addressed return label to the CD player before packaging. If the outer address sticker is damaged, this also creates more security for assignment to the logistics company.

2. Please use a sturdy cardboard box, which leaves enough room for padding at the top / bottom and on all sides.

3. Wrap the device first with a plastic wrap or wrapping paper so that no packaging material gets through the ventilation slots in the CD player.

4. Let the device power cord protrude from the plastic wrap to the rear; Otherwise, it may damage the case of the CD player due to friction.

5. Professionals fill the rest of the room in the box with polystyrene plates (about 2-4 cm, no flakes or loose filling material), which must sit tight. So the shipping weight also stays below 10kg. An investment for non-existent Styrofoam plates you save as early as the postage.

6. Wrapping the device with thick bubble wrap is also possible. Care should again be taken that the device is taut in the box.

7. An inscription "Beware of glass" or "Sensitive electronic device" warns the carrier to be careful during transport.

8. Starting from the post office:

C. Vandenkerchove
Gläserstr. 8
99423 Weimar


This brings us closer to the term "tuning". In the literal sense, the word means nothing other than "adjusting". The term came into disrepute only by the "tuning" in certain car brands. The lowered BMW with a tailpipe-sized exhaust, the chip-tuned diesel, for which the warranty was extinguished for good reasons, or in earlier years the legendary Opel Manta with rally stripes and foxtails created legitimate mistrust regarding the seriousness of "tuning".

Regrettably, no differentiation is made here. After all, tuning is a very serious matter - provided it is done with a knowledgeable hand and the corresponding know-how. Again, a comparison helps with the car world. For example, the originally small manufactory AMG subjected many Mercedes models to such a successful tuning that the Daimler group bought the company a few years ago and has since been operating as an official subsidiary. Almost all models of AMG are based on production cars whose engines, gearboxes or chassis with great engineering skills are brought to maximum performance. Even at BMW, the subsidiary with the famous abbreviation "M" is exclusively concerned with improving the production models. The aim of these measures is not, however, with the help of brute force as many PS herauszukitzeln from the engine - regardless of whether the suspension is now hopelessly overburdened or the performance-enhanced engine dies an early death. Rather, the art of tuning lies in perfectly matched improvements to all the key features of the car, from the engine to the transmission to shock absorbers and stabilizers. It goes without saying that an AMG Mercedes or an M-BMW is a lot more expensive than the original models.

Even when tuning cars, it has to be distinguished whether it is a measure for the improvement of a single property (eg higher engine power) with which another property (for example the chassis) can not compete at all; or a major overhaul that raises the car with all its characteristics to a higher level.

Philips CD players are about the same phenomenon. There are critics of "modification" or "tuning". Sometimes they claim that it is a sacrilege to "attack" one of these players. What the engineers at Philips would have provided constructively, in hindsight anyway can not be improved. Or they even deny that audible improvements through modification are even possible.

Significantly, these critics have never heard a modified player in the interplay of a good investment, let alone conducted a serious A-B comparison with this denial attitude. Those who reject such modifications as impermissible interventions only on principle show that they understand neither market laws nor technology.

Technical possibilities

Before I go into that, I would like to say in advance that I have great respect for the tremendous power of the Philips engineers who developed the compact disc and its players in the 1980s. The development had taken place in the Dutch Philips laboratories in Eindhoven. Many dozens of German, French and British engineers had spent years calculating, designing and designing until the silvery-round "Digital Revolution" finally worked. I would never be so presumptuous to suggest that with a few simple steps, a simple bridged circuit or the premature replacement of some components, you can improve a Philips CD 100, 104 or 304 with just a few hours of work.

To judge where something is possible and what is not, you have to go back about 30 years. Let's start with a look at the components. In the past, only carbon film resistors were available. They not only had large tolerances of 10% and above, they also had a lot of noise. Their temperature behavior was questionable in practice, even a small warming reduced the resistance considerably. Deviations of more than 10% of the nominal capacity were normal for the oil-paper capacitors used at that time. In many places, components were therefore inevitably used whose accuracy was more in the hands of God than on the drawing board of an engineer. The series variations of the devices were correspondingly large.

Resistors are now available with an accuracy of 1% and better. For capacitors, the same applies in principle. The quality of the components has progressed rapidly in these 30 years. Conversely, nowadays, with reasonable costs, it is no longer possible to design a drive as elaborate as a Philips CDM-0 or CDM-1. It would also cost in a mass production about 1000 €.

The result is that even well-known high-end vendors will inevitably have to fall back on DVD mass drives of cheap design, in order to be able to offer CD players at all. The missing inner values ??are compensated by noble housing and high expenditure for marketing and advertisement. Sometimes only a thick bottom plate makes it a seemingly heavyweight from the technical lightweight.

No rational argument argues against combining the best of the past and present worlds. Even looking at a photo shows that the mechanics of a CD 304 are second to none and probably never produced again. These Philips drives will still turn when the remnants of today's high-end players have long since been recycled as PET bottles and car bumpers.


The framework conditions under which products are developed in a large corporation must also be considered when assessing the meaning or nonsense of a modification. Cost laws were the same then as they are today. An engineer can develop even more ingenious ideas - if the controller strikes with the arithmetic pin and explains the idea as too expensive for mass production, it is quickly done. Each group always calculates with the use of components with the second or even third place behind the decimal point.

After all, a simple law also plays a role: Behind every device and its development people are stuck with their peculiarities. Who does not know the situation that a young engineer has a bold idea or proposes an unusual path, but fails because of the incorrigibility of a superintendent gray in honor? Or that a small team of young developers is duping the desk bosses by providing a stage of development for a product, but that will not be pursued? For some constructive peculiarities of the Philips CD player in particular, it is so. Some excellent possibilities of the CD player remained strangely unused even then. Some sound-enhancing properties would have been due to the multiple use of perhaps one or two British pound or Gulden can be significantly improved already in the initial phase.


The conclusion of these discussions from different perspectives is clear. There is no logical argument against the sonic upgrading of a CD player with modern, superior components. There is also no rational argument against technical improvements in places that were not used in the original model for cost reasons. Nor does it make sense to leave features introduced for marketing purposes only if a device sounds better without them.

Whether we are talking about tuning or modification, it does not matter as long as the changes happen professionally. As a professional I refer to a modification when it takes place on the basis of many years of experience and results in a significant increase in all the sonic characteristics of a CD player. Sound effects, such as an accentuated presence or a more accentuated bass when playing music, I reject from conviction. Also, measures that could lead to a shortening of the life of a device, do not meet the standards of a serious modification.


In order to achieve the goal of a clearly increased sound quality with a CD player, apart from the know-how acquired in long years also the use of stale money belongs. For example, many quizzes have found that a quartet of precision capacitors cost $ 35 to outperform the more electrically equivalent, but more inconsistent types for $ 7, and more expensive components are required. To professionally modify CD players is also a certain addiction to perfection.

But what could be better than, for example, listening to an old CD 304, which already sounds good in its untreated original condition, and finding that it sounds decidedly better? And then in the next step to compare the restored with a modified CD player. To hear that music is no longer played, but gets under the skin. That a piccolo flute retains its silvery, but has lost its sharpness. Or that the drummer in truth did not take a break, as the unmodified CD player suggested, but in between tenderly worked on the fur several times.

Technical improvements and modifications serve the music experience at the highest possible level.