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VintageVibe.com
Always keep AC wires away from the input stage as well as the pre amp. Input stage is where your RCA plugs into the board. Tie them up and away. This reduce 60 cycle hum.
1. You can tune your Wurlitzer without a soldering iron or file, by moving the reed forward or backwards, you can change pitch by 2-3 semi tones in either direction. Usually a reed is within this proximity and you can tune without a solder iron or file. Sometimes a piano is beyond this and you will be forced to used a soldering iron or file.
2. On your harp you will see screws that are used as ground connections, there are also screws that bridge a connection on top of your pick ups under your dampers always tighten these, loose grounds can cause noise thru the input. Secure grounds can make a serious impact on quieting your amp.
3. Sticky keys are caused by moisture and they need to be eased by prying apart the felt bushings underneath the bottom lip of the key as well as the center balance rail bushing in the middle of the key. (We sell the perfect tool) but you can fumble with a screw driver.
4. Voicing your pick up will change the harmonic quality of your reeds, by bending the aluminum pick up down or up slightly you can hear a change in tonality. You can bring out the overtones or remove them this way. The pick up have a voltage across them so only make changes when Wurlitzer is turned off or you could possible short your amp.
5. Loose or noisy action parts can be tightened or quieted somewhat by three screws located in the rear. One for the dampers, hammers and whippen assemblies. Go thru all and tighten with a long very thin flat head.
6. Bad action is caused by a number of issues such as warped hammer rail or incorrectly adjusted capstans on the let off or the lost motion, incorrect key dip which will affect everything else. These are regulation procedures for all Wurlitzer’s if you want the optimal performance out of your piano. (We sell these tools and use them on all repairs). Unfortunately without the tool it cannot be performed.
7. It's always a good idea to use cable ties and tie all of your wires neatly and away from the pre amp input stage. This helps prevent loose wires and breakage due to wires being pulled on or moving around too much.
8. Always keep the AC cables away from the amp, these are the black cloth covered cables coming from your transformer and they run along the back of your amp. This is a major source of hum.
9. Try removing all keys and vacuuming out your entire Wurlitzer, this will keep dirt out of the pick ups which is a major factor on noise.
10. Intermittent loud distortion, turn off and lightly bang up and down on the keys, this will dislodge any dust in the pick ups. Or it could be a reed just slightly touching the pick up on hard hits. Again, remove keys and vacuum out inside of case.
11. Make sure you tighten all harp grounds especially input cable ground. Before installing new amp, clean all ground connections with Emory paper or something like it. Especially the metal stand-offs that the amp will set on.
12. A good test to see if your harp is dirty/ dusty and causing noise, with the amp on just remove the RCA from the amplifier if the noise goes away, your harp has either dust or dirt on it or you have bad ground connections. If there is excessive hum that does not go away, read # 13
13. If you find any excessive hum for any reason, try a ground lift at the wall socket.
14. Check with meter in ohms scale your grounds from the ground side of the harp to the amp, if you have anything above 0.5-1 ohm you could be introducing hum into your signal. when ground connections become oxidized you start losing ground. Clean all connection and secure grounds tightly. Purchase our conductive copper foil, it's amazing for securing grounds, we get all of our grounds to read 00.0-00.1 with the use of this stuff. Get it on our website.
L.E.D Modification:
Vintage Vibe has come up with a series of calculated L.E.D modification formulas for Various AC powered lamps and bulbs with various resistance. When dealing with AC especially near audio paths you can get stray Hum entering that audio path. We designed the L.E.D mod which is run on DC voltage to take the place of the AC power. L.E.D will run about 100 times longer than your standard bulb or lamp and also burn brighter.
There is no AC to interfere with your signal, so ultimately your signal will be cleaner. We especially found this to be true in Wurlitzer E.P's. In reference to the older 100 series pianos, you have AC from the Volume pot and the lamp assembly running a long length together with audio wires. Old deteriorated wires are prime canidate for breaking down and allowing hum to be picked up. We now redress all wiring with shielded cable, remove lamp and add an L.E.D mod to eliminate any possiblility of AC hum in this stage. we use this technology also for Rhodes power supply lamps.
Sympathetic Vibrations:
Noise such as vibrations, after ring of a note even when damper is working properly or monophonic sustaining when notes are played can be attributed to a reaction caused by frequency. Frequency can play out a number of symptoms heard inside your piano.
When a note is generated a certain frequency related to the note sounds, everything inside the piano has a frequency it reacts to or it's own reaction point. Frequencies in the mid to upper spectrum will especially agrivate thin metal objects. Certain frequency can agrivate or stimulate objects inside your piano to start vibrating. Often it is an exact frequency that will activate such a distubance, say for instance middle C# may cause an aweful feedback or rattleing but the C or D next to it will not.
We can see now that everything has an exact frequency it reactes to. The wurlitzer Electric Piano is a very complex instrument when it comes to frequency, it is very suseptable to these kinds of reactions. What we need to look at is how to stop them.
In my experience rattling vibrations and monophonic feedback or sustain is caused by loose screws a majority of the time. Let's list some;
1. Loose screws on the back hinges
2. Loose music rack screws
3. Loose harp screws
4. Loose pick up screws
5. Loose ground screws
6. Any screw in the harp area should be checked for tightness, any and all
7. Rubber pads should be installed on your reed bar shield to absord sympathetic vibrations cast by frequencies.
8.Wood to metal contact, particularly Damper arms vibrating against pick up shield
9. Speaker screws, should be snug but not to tight as to have cone rubbing on the case.
10. Music rack grommets should be fresh, faceplates should be secure,cables and wires should all be tied and secured, rubber pads should be placed between hum shield and top case.
11. Inspect all grounds and screws under damper arms, particularly on 200A models where a reed bar shield is present. This shield and the hum shield are major sources of vibrations.
12. Oscillation occuring inside the closed lid can lead to monophonic feedback or sustaining of note, again this can be caused by loose screws causing vibrations that perpetuate the symptom.
Another cause could be too much gain from the amp causing speakers to feedback inside the enclosed case. If this is the case turn down your pre amp gain pot on the amplifier.
These are annoying symptoms which can all be fixed, if you take the time to troubleshoot and find the cause. | 
