We can repair most any vacuum tube based amplifier or other pro audio component to factory specifications or better. The performance of many older products can often be improved by installing better quality passive components that were not available at the time of manufacture. Some examples of this are electrolytic capacitors, metal oxide resistors, film capacitors and silicon diodes. Additionally, at the time of repair, we will rewire the a/c line input circuit per current electrical code.
If originality is an important consideration, we have a large inventory of NOS (new old stock) tubes and passive components and can restore your equipment, as near as possible, to stock condition, including the removal of previously performed modifications. Though in most cases, performance in regard to hum, noise, and reliability can be improved with new manufacture parts, when the situation dictates we can restore most equipment to factory new condition. We work with a transformer rewind shop that can repair most mains, choke and output transformers to original specification. We also offer cabinet repair and recovering, grille cloth replacement, and other cosmetic repair services, and can obtain most types of handles, corners and feet as well.
We offer "flat labor rate" full rebuild services that are a cost effective way of giving an older piece of equipment a new start on its second life. Using as an example a typical all-tube signal path guitar amp, here is what's involved. The first step is a detailed physical inspection, followed by the standard maintenance outlined in paragraph in blue above. The a/c input circuit is rewired to current electrical code and, if required, a new mains cable with grounded plug is installed. Next, the power supply (including the bias supply and (in dc filament circuits) the heater supply) is rebuilt with all new filter capacitors, silicon rectifiers and dropping resistors. The output tube screen resistors are replaced. All internal wiring is checked and repaired as required with the input wires replaced by shielded cable, and all leads are properly "dressed" and secured. All solder connections are checked and touched up. Any worn or dirty pots, jacks, switches or tube sockets that don't respond to cleaning are replaced. All signal path components are checked, and any found to be out of tolerance are replaced. A new set of tubes is installed and burned in for 24 hours, after which calibration of bias or other adjustment is performed. All plate voltages and cathode currents are recorded for reference. After a 2 hour full-power test period, calibrations are verified and the amp subjected to the final test - making music
! Only after we're satisfied with the tone is the amp securely (heavily bubble packed and double boxed, with the tubes separately boxed) packaged, and sent back to the client with a 6 month all inclusive warranty on all parts (including
tubes) and labor. We have performed this service on many different models of Ampeg, Fender, HiWatt and Marshall guitar and bass amps, among others.