Chicago Amp Works

Professional, expert amp repair service. From tune-ups and maintenance to re-tube and bias, recapping and custom mods, we can make it happen with your rig.

Amp Repair, Chicago Style.

We are not taking in amps for service at this time. Updates to follow soon, we hope!

Specializing in tube and vintage amps and effects, expert technician Pat McKeever brings a toolbox filled with more than 25 years of experience repairing, maintaining, and customizing amplifiers. Whether yours is new or vintage, solid state or tube, 1 watt or 700 watts, chances are he’s fixed it before and will make it sound better than ever. His discriminating ears won’t send it home until it sounds as great as possible.

You’ll find that Pat continues the Fret Works tradition of professionalism, honesty, and dedication to getting it right.

COVID 19 hours: Dropoff your amp from 2pm-6pm Monday through Friday or 10am-5pm Saturday. Email or call (773) 698-6246 to inquire.

Pat McKeever
vintage tube
Pat McKeever

No need for an appointment

You can drop your amp off any time during our business hours.

General Pricing Policies

Unlike most guitar repairs, amps require testing and close inspection to get an accurate diagnosis and cost estimate. That said, some ballpark costs for common repairs are listed below as a general guide.

Every amp repair begins with an Amp Check/ Diagnostic

A $50 deposit/bench fee is collected when you drop off your amp as a pre-payment on the first 40 minutes of work and is credited toward further repairs. (For example, if the diagnosis calls for an $80 repair, your remaining balance would be $30)

Amp Check / Diagnostic

  • A comprehensive inspection, scope, and diagnosis of specific problems as well as a thorough check of your amp for other hidden issues
  • Detailed estimate of recommended services, including turnaround time and cost. We only do the repairs you authorize and will let you know in advance what to expect
  • Basic cleaning and tightening of controls
  • Sometimes this is all an amp needs. If that’s the case, that’s it!

Common Amp Repairs

Tune-up / Check-up: $100-140 depending on model

Recommended as annual maintenance. Your amp’s exposure to dust, vibrations from handling, and normal usage can all lead to intermittent noises and malfunctions (usually at the worst possible time!) Keep your rig in tip top shape with this basic service.


  • Cleaning & tightening of pots, jacks, switches, & controls
  • Cleaning & re-tensioning of tube sockets
  • Testing tubes for malfunction, noise, & microphonics
  • Re-soldering loose/questionable connections
  • Checking/adjusting bias (idle current)
  • Visual & tap inspection of all components
  • Measuring output signal on oscilloscope
  • Audio sweep test of speakers
  • Testing with guitar or bass
  • Recommendation and estimate for other needed repairs and maintenance

Re-tube / bias adjustment

Labor estimate only – prices do not reflect cost of tubes or parts.
Some common examples:

  • Fender Princeton Reverb: $70+
  • Fender Twin Reverb: $80+
  • Marshall JCM 800: $80+
  • Ampeg SVT Classic: $100+
  • Fender Hot Rod Deville: $80+
  • Vox AC30: $100+
  • Ampeg Gemini / V4 / Reverb Rocket $100+

Replace filter / electrolytic caps

Labor estimate only – prices do not reflect cost of parts.
Some common examples:

  • Fender Princeton Reverb: $100+
  • Fender Twin Reverb: $120+
  • Marshall JCM 800: $160+
  • Fender Hot Rod Deville: $120+
  • Vox AC30: $140+
  • Ampeg Gemini / V4 / Reverb Rocket $140+

Replacement parts

  • We stock high quality replacement parts like J/J Tubes, Sprague or F&T Caps, Switchcraft jacks, and CTS Pots.
  • If you prefer something else, just ask! Groove Tubes, Mullard, Tung-Sol, Electro-Harmonix, Sovtek … you name it.
Vintage tube

Sweet Amplification

Chicago Fret Works is the exclusive dealer of Sweet Amplification amps, hand built by our own Pat McKeever.

Sweet amplifiers are made one at a time, based on tried and true “all tube” circuit designs using the best components available.

Visit for more information.

Sweet Amplification

Trophy Case

We’ve serviced all these brands and many more