We often see old vintage and modern transistor and tube valve amplifiers, if your amplifier has shorted and blown output transistors or a transformer we can replace it, either using original parts from the manufacture or compatible parts we have on the shelf. In addition we work with bespoke manufactures who are able to wind replica transformers to original specifications and custom make components for us.
Generally our services only include repair however we have carried out a small amount of modifications. We will consider all modifications however if you appear with a forum related modification we think is unacceptable or will not deliver what you expect please do not be offended if we decline to modify.
There are repairs we do all the time for amplifiers, these include sorting out crackles from dry joints on PCBs, excessive humming, broken jack inputs, output valve rebiasing and replacing broken valves, crackling or not working pots and controls.
More complicated repairs are when there has been a fire in the amplifier and many parts need changing including transformers, rebuilding of PCB damaged tracks, faultfinding of class AB output amplifiers blow FET and MOSFET stages.
Most of the faults we see are as a result of general wear and tear, with the majority of faults being more noticeable when the amps are running hot in both valve and transistor.
Often hums are as a result of storage capacitors drying out, think of them like water reservoirs smoothing the supply voltage. Capacitors used in storage have a sandwich of conductors and insulators which are soaked in a liquid called an electrolyte. Over many years of use, heat and wear the liquid dries out and renders the capacitor useless.
Other sources of humming can be broken screens, and missing earth connections either on mains or signal.
Crackling and jumping volume on pots
Crackling pots can be annoying and sounds like static when turning, but in worse case situations you can find that a volume dial is either off or 100% on causing all kinds of problems with in particular master volumes!
In the first case we will soak the pots with some switch cleaner which cleans the oxide, dust and grime from the resistance track. In 90% of the cases this solves the fault and allows you to go for many years with a quiet control. The other 10% we will change with a like part.
Actually we prefer the older amplifiers and you cannot beat working on a vintage valve amp to repair, hand wired on tag board with old components is what we really enjoy. When we repair older vintage valve amps we try as hard possible to change with original style components, obviously it is hard and sometimes uneconomical to replace like for like but we will do our best to maintain the vintage sound you love.
If you have a burnt out transformer for your valve amplifier we have some great links with transformer winders who can make identical vintage transformers from old plans and schematics.