How Tropical Fish Restores Wurlitzer Tube Amps Like the 145 120 700 112

You may have heard that we restore hand wired tube amps that are found in various Wurlitzer Electronic Pianos. This article is intended to answer some questions on what we do, what our process is and what you can expect.

Real quick, if you have questions about whether your amp needs to be restored, if it is something you can do, or would like some parts to do it yourself please check out our articles. Now on to our process.

What will Tropical Fish do to restore my amp?

We take a ground up approach to restoring your tube amp. What that means is, instead of rooting out the handful of really bad components (and possibly leaving some half-bad ones) we replace all small caps and resistors. We also re-wire tube heaters and replace worn out sockets. Perhaps most importantly, we re-organize and optimize the circuit layout for the lowest possible noise floor and modify the circuit slightly by adding additional components, outside of the original scope, to improve the circuit further. In short:

All new small components (caps & resistors) inside the amp and terminal strips
New tube sockets
New tube heater wires
New wiring harness including potentiometers
Improved component layout, and improved circuit
Grounded (IEC) power socket

Why does Tropical Fish only do a COMPLETE restoration on amps?

Because every component in the amp works together to amplify your sound, and almost any one component failing can cut the sound, the amp is really only as good as its weakest link. Working this way saves both you and us time and energy, and gives you a beautiful sounding amp when we’re done.

Does Tropical Fish replace the tubes?

We only replace the tubes if they are no longer functional or extremely weak.

Does Tropical Fish replace the transformers?

The first thing we do is test the transformers, and advise if they are bad or not. Transformers are one of the more expensive components to replace (PT is about $150, and the OT is about $100). We are happy to replace those components, but will definitely leave them if they are still good. Transformers are pretty rugged and more often than not are still good.

Does Tropical Fish replace the wiring control harness and the potentiometers?

Yes we do this every time now. This is included in the cost of the amp restoration. We find that replacing this wiring is highly beneficial to the overall function of the amp and will increase the repairs longevity.

Does TF add a three prong (generically referred to as an IEC) power socket?

Yes, we always do this and it is an upgrade that we make a part of every amp repair.

What does TF NOT do, in an amp restoration?

Your amp will basically be new again. For tube amps, ideally the only remaining original components are the chassis, the transformers, and the tubes. It would be hard to tell your amp was restored by simply looking at the outside of it, but when you look inside, it is almost entirely brand new! You will definitely hear a noticeable improvement.

Do you move the power switch to the amp chassis?

Yes, we do this because it reduces the noise floor.

Options?

Yes. We can make the rectifier solid state (this eliminates the rectifier tube of course, and subtly changes the sound to be a little tighter in the bass notes).

How should I ship my amp?

Pack the amp generously. For tube amps, always remove and individually wrap the tubes. Please include the wiring harness (you may include the cheek block as well).

What does the repair cost?

We have a flat fee for amp repairs, because of our ground up method of repair we detailed above. The added fees could be if any transformers are bad (often they are not) or any tubes are bad (half of the time they are still usable). Return shipping is included. Inquire about our current repair rate for your amp.

Can I mail my 112, 120, 700, 720A, 140B or 145 amp in to Tropical Fish?

Yes you can. Reach out to us on either our repair page, or our contact page to ask us where to send it.