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Teac VRDS Copland 288 Rubber Tray Repair



The Teac VRDS mechanism used in many high end players does not age well. The gears go soft and start to perish making the unit skip on playback or the tray fail to open and close. These gears are very hard to find now and expensive if you do manage to find some. Therefore unless you have a 3D printer and a good set of gears as a template then I would avoid paying too much for any Teac based cd player.


Removing The Tray Rubber

Another issue that arises is the rubber coating on the tray on some models starts to perish. At first it goes very soft and slightly sticky which results in it collecting and holding dust. If you rub the surface to try and remove the stuck dust the rubber will usually start the peel away. Unfortunately it does not come off clean but it is possible to remove the rubber coating completely.

The trick is to use isopropyl alcohol diluted with distilled water. This is the stuff you can mix yourself to clean LCD screens without smearing. You can buy the isopropyl alcohol and distilled water separately from ebay and mix them in a spay bottle. A 50/50 mix is typical.

Albino 3 Synth Patches (October 2014)


Just a few patches for the now defunct synth Albino 3. I still think this is a great synth and the interface makes it easy to get to grips with. It is also quick to create variations of sounds. Many soft synths have a sonic signature and many patches always end up sounding a bit too similar. These patches are a mix of bass, percussion, fx and a few pads aimed at electronica and berlin school sytle.

33 Patches

Audjoo Helix Patches (October 2014)


I have made these Synth Patches for Audjoo Helix Synth. They are mostly Pads Suitable for Film, Electronica, Ambient, New Age, Berlin School etc. Helix is a Wave-Table-Shaping, Virtual Analogue, Physical Modelling Hybrid Synthesizer with a deep rich high sound quality that makes it well suited to pads and textures with depth, although it is quite capable of Bass and Leads etc.

Some of the Pads possible in this synth remind me a little of the more powerful Native Instruments Absynth at times and this is not a typical thin sounding Vsti. I'd rate this along side the excellent Albino 3 from Rob Papen, although Albino is far more obvious to use from a brand new user perspective. A great all round synth and very easy to use once you get to grips with the unique interface.

115 Patches

Radio Massacre International Cover Re-design


I have been re-designing some of the older RMI covers in the new style of SynGate releases. Click the title for more and full size versions...

auCDtect Lossless Audio Checker


When I switched from Fedora to ubuntu n order to escape Gnome shell 3.xx I found that auCDtect which I used to check the validity of lossless files would no longer run using the tar packaged version without tweaking by installing old compat libs. Anyhow it seems that the static binary inside the rpm package works even better. Just open the rpm with the archive manager and extract the binary file. Copy it to /usr/bin if you want.

Pass Labs B1 Buffer Rebuild



Having sold the last B1 buffer I built I ended up building another. I had a spare pcb sitting around for a while and since it is such a good pre-amp, easy to build and the fact I had 90% of the parts already it was a situation of... might as well. It also meant I could use one of those nice aluminium cases from modshop in Italy to match my copland cd player and the lightspeed pre-amp case. Solid state builds such as this simple design do not have much to go wrong and testing is safe unlike tube gear. A big difference working on 18V here rather than 300V plus.


Matched Vs Unmatched

In the first build I used a quad matched set of FET's having read forums saying the pre sound better with a matched set. Anyhow seeing as I has some FET's already but not matched I ignored the usual chatter and just built it with what I had. I can honestly say that in my build it makes no obvious difference. Channels are still balanced and it has the same character B1 sound. Infact this time I had some better output caps.



Grado PS500



For the past year I have been using a pair of stax lambda pro electrostatic headphones with my Copland 288 cd player in one of my setups. I sold my Martin Logan speakers and wanted something as good but more suited to a small room, able to be used any time of day or night and as loud as I wanted with minimal external noise. Quality headphones are very hard to better with similar priced loudspeakers. They also provide a highly involving listening experience. Their diaphragms are much lighter than typical dynamic speakers and so have timing and pace unmatched bar the very best speakers. Electrostatic speakers do try to overcome this problem by the use of lightweight film which only weigh a few mg. Dynamic coil based systems have the weight of the coil and cone to move, including mechanical resistance from the 'spider' and surround.

Linn Valhalla Supply Repair


Some Info

I recently helped a friend to repair a Linn Valhalla power supply pcb. It would seem that these are prone to particular failures and a common one is low motor torque in which the motor buzzes or vibrates since it is too weak to drive the platter. This turned out to be R32 (560k) on the board. R33 had also deteriorated with the ceramic body breaking up. I have uploaded the circuit as a png and pdf file which some may find useful.

If you are having motor problems I would first replace these 2 resistors R32 and R33. Failing that then the next step is to replace the small orange caps around the logic chips if the motor does not turn at all.

If the unit will not power up then some early Valhalla units could blow the bridge rectifier so you will need to test this and the large power supply caps it feeds, assuming the fuse is ok. If the bridge has part blown then AC can reach the caps and damage them. If replacing any parts then consider using something slightly higher rated and higher quality as the standard parts are nothing special.


Lightspeed Attenuator Rebuild


Lightspeed Passive Pre-Amp

I have slowly been working on building another light-speed attenuator but in a much nicer case matching the chassis type used in the Nelson Pass F5 and F3 builds. This again is a scratch build rather than a kit. As usual I have built it with parts I already had to save cost but needed to buy the case from Italy and the 4 x Silonex NSL-32SR2 LED-LDR's from in the states.

The circuit is simple so I built it on proto-board with hard-wire links on the copper side with the shortest routing possible esp on the audio links. I used some left over silver wire I had on the links that carry audio signals and these are situated at the back of the unit very close to the RCA sockets. I also avoided fitting a selector switch so it is 1 pair RCA in and 1 pair RCA out for the most direct signal route. That way we don't lose the advantage of using the LDR's to eliminate the usual audio carrying volume pot and its contacts and spoil that by routing audio through a selector switch or relay.

F5 Power Amp Headphone Adapter


Power Amp Driven Headphones

I was wondering if it was possible to drive a pair of regular dynamic headphones from a power amp such as my Class A F5. Sometimes I have periods of time without a pair of speakers such as if I have sold them and looking for something new to replace them with. In the meantime it would be nice to use a pair of headphones which quite frankly are hard to beat with most speakers. It seems that you need to spend quite a few more in pennies on the speakers to match even a modest pair of cans and once you are in the realms of higher end headphones then most speakers don't come close to the same levels of enjoyment and immersion in the music.

I found a neat little project over at ESP. It is nothing more than a 6 resistors, 3 per side to give the correct voltage levels and impedance to the headphones. You could probably solder these resistors in-line with the headphone to speaker banana leads and heatshrink them but I used a small box, proto-board to hold the resistors and some nice nylon sleeving.

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by Dr. Radut