REPAIRS

With over 20 years of experience servicing and repairing pro audio equipment, Pro Harmonic is well placed to service equipment from digital processors to tube compressors; vintage microphones to guitar amplifiers.

SOME REPAIR STORIES :

AWA G54639 - repaired with attack and release controls added. Custom power supply built
AWA BAR-2 - originally a field four into one mixer - direct outputs, pad, phase and phantom added

Gates Limiter

 

with the hood down!



its not every day you have on the bench a slab of tube limiters made by AWA, CBS and GE

all refurbished - re-tubed

AWA G51501 modified with attack / release and original fixed dual time constant / varible selector added.

CBS Audimax - kept original with just a passive output level trim added

rare GE BA-7-A - all original - this unit uses RF modulation for gain control

STC vari-mu limiter - custom external PSU built / input level / attack and release controls added
Neve console - 12 Stereo Line-In channels - refurbished / industry standard Dsub connectors added
A nice U67 - refurbished - PSU rebuilt / repainted - all into a neat carry case
the exceedingly rare ITA LA-1A - a vari-mu limiter, using a single 6386 tube for gain reduction, hinting at the future styling of the LA-2A
what can i say? two Fairchild 670 Limiters in road ready cases with built in step down transformers
AWA 2G58250 - is this one of the greatest vari-mu limiters ever made? recapped, new metal film resistors, hand selected tubes - a huge sound with three sidechain modes - single / dual / agc
- technical specifications :noise -62dBu (unweighted), max output level > + 28dBu, distortion 0.03%, freq response 0.5dB down at 20Hz and 50kHz

the gauntlet was thrown down! was it possible to squeeze a pair of AWA BIG-1's into a single rack case?

AWA BIG-1 PAIR - stereo link, variable attack and release added


Telefunken U47
pair of U47's fully refurbished - capsules rediaphrammed / PSU's rebuilt / reconditioned VF14 tubes

EMT 251
serviced and EPROM upgrade to add original EMT 250 programs


Fairchild 670
the holy grail landed on the bench. Due to the exceptional build quality of these units little work was required. Some electolytic caps replaced, minor repairs to the meters and a couple of resistors replaced. Re-tubed with hand selected and graded tubes.

AWA G51501
fully restored. This unit had been previously modified, with one whole limiting section removed. This was restored and a variable attack / release option added
A pair of AWA 2658250
fully re-capped , re-tubed and restored. One unit was modified with attack and release controls added.

Huge sounding Australian made compressor / limiters


Cloned Neumann U47
This brand new U47 clone was build from the ground up around a EF14 tube, rather than the original and now almost unobtainable VF14 tube.

The PSU supplies regulated heater and HT voltages with a unique scheme for obtaining the required tube bias.

From the owner : "The mic sounds great, the best i've heard. The bottom end is very tight and mids warm and forward, may convert the other U47 to EF14 after hearing this"


dBx 160
fully refurbished / aligned. Installed into a standard case


Neumann SM69 - custom PSU with pattern switching
Neumann U47 and U67 - fully refurbished

Neve Kelso
fully restored!


Remote tape control and remote meters for MCI JH-110

Urei LA-3 on arrival in the workshop!




Rear View - showing addition of Mains IEC socket and Input and Output XLRs mounted on panel.

Urei LA-3 after servicing and 'racking'. - Opto-cells in TB4 modules were replaced with Original spec-ed devices.
All capacitors replaced with high performance Bi-polar types, input impedance and gain structure modified and compress/limit switch moved to front panel.
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