tinny sound

EBS Amp repair – HD360 Bass amp repair

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EBS amp repair

Today I repaired an EBS amp repair on a 2 hour turnaround! The customer brought the unit to my Newark workshop from Nottingham.

EBS are a swedish brand. It’s the first time I’d worked on an EBS unit, though I’ve played alongside bassists who’ve used EBS gear and been quite impressed.  I contacted their technical support team for schematics and they were great – after I’d signed my life away they provided me with schematics very quickly.

The amp had an intermittent fault on the filter (EQ). When engaging the filter active switch there was an intermittent buzz sometimes, sometimes a very tinny treble sound, sometimes too much bass and sometimes normal operation!

The problem turned out to be with the bass control, which had an intermittent resistive short to ground at all times. Fortunately I was able to repair the bass amp with parts that I hold in stock. It arrived at 10am and was back after repair and PAT testing with the customer by 12:00.

If you need an EBS amp repair, please get in touch.

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.