Posts in Guides
How to Replace Vintage Filter Capacitor Cans

The filter capacitors in many amps are mounted in a metal can, which can be an obstacle to successfully recapping the amp. These days, filter cans are only made in a limited values, so it's hard to find the exact match. Mounting the caps outside of the can is another option, but finding the space can be tricky. Removing the can can leave a giant hole, which can allow dust to enter the chassis over time. So, what's the best way to replace can-style filter capacitors?

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What to Look for When Buying a Fender Rhodes Electronic Piano

When we’re thinking about buying a Rhodes, there are a few criteria that we use to judge potential purchases. We’re mostly concerned about how much work the Rhodes needs to become playable - and if you want your Rhodes to be a functional keyboard and not just a moderately inconvenient buffet table, you probably care about the same things we do.

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How to Fix Hum in Your Wurlitzer Electronic Piano (Or Other Vintage Amp): Part II

In Part I of our guide on fixing hum, we listed some easy fixes. In Part II, we’ll go into further detail on techniques that require some prior electronics experience to execute. It’s worth checking out Part I first, because it listed some simple, non-invasive things that you should always be tried before diving into the amplifier’s circuitry. For the purposes of this article, we’ll assume that you already tried everything in Part I. This includes:

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How to Fix Hum in Your Wurlitzer Electronic Piano (Or Other Vintage Amp): Part I

Before we start, a disclaimer: hum should be addressed on a case-by-case basis, because every vintage amp is special and degrades in its own way. What cures one amp may not work for another. That said, reading this guide should give you a good starting point on how to address your own hum problems. This guide is pretty basic and going to assume that the only piece of test equipment that you have is a multimeter.

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What components should I replace in my vintage Wurlitzer amp, and why?

Tropical Fish now offers several kits containing replacement components for all Wurlitzer amplifiers. If you already have experience working with electronics, these kits offer a convenient DIY option for restoring your amp. Each kit contains the same high-quality components that we use in our own restorations.

For all amplifiers, we offer the Basic kit as well as several add-on components packages. The Basic kit contains all electrolytic capacitors, power supply resistors, and a few input components for the preamp. For many amplifiers, replacing these components is sufficient for improved reliability and performance.

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Troubleshooting My Wurlitzer Electronic Piano’s Tube Amp: User Serviceable Edition

Early Wurlitzer electronic keyboards dating before roughly 1962 all featured on board tube amplifiers. Tube amplifiers offer a unique warm & full sound and what could be better to play your Wurly through right?  To many, however, a vintage tube amp can appear intimidating, high-maintenance and something only audiophiles should own. In the world of vintage amplifiers, however, a tube amp is more likely to be easier to troubleshoot should anything go wrong with its functionality.  In general vintage tube amps have large easy to check and replace components, while vintage solid state amps often have smaller, more delicate components. 

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In Restoration: Removing Duct Tape from the Wurlitzer 140a

This Wurlitzer 140a belonged to a producer for many years, and arrived at our shop in well-used condition. By that, we mean that it was pretty banged up and showed evidence of previous repairs. Also, because multiple latches were missing, the lid didn’t attach very well. At some point, it had obviously once been held in place with duct tape.

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How Does a Wurlitzer Electronic Piano Work?

All Wurlitzer electronic pianos - from the model 112 to the Wurlitzer 200a - are more or less built the same. There are subtle differences in the mechanical action and the amplifier, but they all follow the same basic principles.

When you hit a key on the Wurlitzer electronic piano, a felt-tipped hammer rises and strikes a metal reed. The reed vibrates to a certain pitch, which is determined by the weight of a lump of solder at the end of the reed. A pickup converts the vibration into an electrical signal, which is finally amplified by the onboard amp and sent to a speaker.

Here’s how it works in a little more detail:

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How to Convert a Wurlitzer 206 into a Wurlitzer 200

The Wurlitzer 206 is the student version of the Wurlitzer 200. It is equivalent to the 200 in every day, but it is mounted on a cabinet instead of legs and some features of the amplifier are disabled. However, all of the components that are in a 200 are also present on the circuit board of the 206. Enabling vibrato and the aux output is therefore as simple as adding some wires and a 10k potentiometer. Here is how we do it.

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What is the Difference Between a Wurlitzer 140 and a Wurlitzer 200a or 200?

Wurlitzer in the 140 series are transitional models: more reliable than Wurlitzer’s earlier electronic pianos, but not as portable as later models. On the other hand, the 200-series is the iconic final iteration of Wurlitzer keyboards: smaller, lighter, more chrome. If there’s a Wurlitzer 140 (or any of its many variants, from the 140b to the 145) that has caught your eye, you may be wondering if buying it is a good idea. How does it stack up against the 200a? Does it require more work? What are the practical differences between them? This guide is here to help.

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What is the Difference Between a Wurlitzer 200 and a Wurlitzer 200a?

The Wurlitzer 200 and 200a are extremely similar. If you are trying to decide between the two models, you should first of all realize that there are no bad decisions here. When restored, both types of keyboard are equally reliable, high-quality instruments. And, of course, both of them have that iconic Wurlitzer sound.

If you can’t decide between a Wurlitzer 200 and a 200a, this guide may help. Below, we’ve listed the differences between the 200 and the 200a.

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Gibson GA-5 vs Fender 5F1: Circuit Analysis

We’ve written about the history of the Gibson GA-5 before. Basically, the GA-5 was Gibson’s first practice amp offering. Not only was the circuit nearly identical to the Fender Champ, but the GA-5’s cabinet was suspiciously similar as well. Eventually, Gibson adopted a more original exterior design, but the circuit remained pretty much the same. This means that a GA-5 of any vintage is an extremely affordable equivalent to a 5F1 Champ.

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Vintage Component Spotlight: Carbon Composition Resistors

Carbon composition resistors are those brown cylindrical resistors that you’ll see in most amps made before 1970. All resistors produce Johnson (thermal) noise, a byproduct of the fact that resistors dissipate heat. However, depending in their material composition and shape, resistors may produce other types of noise as well. Carbon composition resistors produce the most noise. But is this really a bad thing? Yes and no.

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Does My Wurlitzer Need New Key Bushing Felts?

If you flip a Wurlitzer key upside down, you’ll see two holes underneath. These holes line up with the two metal pins in the keybed that guide the key’s vertical travel. They’re called the key bushings, and they’re lined with felt. As the keyboard is played, this felt becomes compressed over time and the keys no longer fit snugly around the key pin. Or, if these felts become damaged, they could prevent the key’s smooth travel and the touch-responsiveness of the keyboard becomes compromised.

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Would Your Wurlitzer Benefit From Servicing?

Some vintage keyboard are in a state of total dilapidation, and will obviously need a lot of work before they can be played. But others are in better condition. They turn on, sound comes out, all or most of the keys work. Is this enough? When can servicing a keyboard that “works” make it perform much better?

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