fx loop repair

Henriksen amp repair

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henriksen amp repair - henriksen bud 1

I love getting something new on the bench, so this Henriksen amp repair got me quite excited. It’s a Henriksen Bud combo.

I hadn’t heard of Henriksen before, but after a bit of research discovered that they are a US based high end solid state amp, in the same market as the Polytone and AER brands.

The owner had inadvertently shorted out the Channel 2 FX loop to the speaker and killed channel 2. This destroyed an opamp in the signal path. The amplifier uses standard components which I keep in stock so I was able to repair the amp and turn the job around within 6 hours of it arriving in my workshop.

During this repair I spoke to Henriksen by email and found them very helpful. Certain North American companies aren’t always interested in supporting their products in the UK so I’d highly recommend Henriksen based on my conversations!

If you need a Henriksen amp repair, please do drop me an email.

The owner was pleased with the job:

henriksen amp repair - henriksen bud 3

Hendriksen amp repair

henriksen amp repair - henriksen bud 2

Keyboard amp repair – Carlsbro Colt 45.

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Keyboard amp repair Calrlsbro colt 45-1

This keyboard amp repair was for a Worksop based violinist who uses the full range speaker with his electric violin.

The amplifier was obtained second hand and had developed an intermittent problem in which the amp would drop out almost completely, leaving only a tinny high frequency signal. At first, I suspected that the LF driver or the crossover had become damaged, leaving only the HF driver active in the coaxial speaker. Normally, you would expect an HF driver to be damaged first, but LF drivers are still possible to damage.

However this wasn’t the problem. In the end I fixed the amp by replacing the corroded FX send jack and phones connectors. The shunt contacts on both of these interrupt the audio signal so they must be kept clean. To complete the Keyboard amp repair I then put the amp on soak test for 2 hours to verify that there were no further problems – there were none!

I shot a quick video part way through diagnosis:


 

If you need a keyboard amp repair, please drop me a message.