Amplifier Experts Logo




Amplifier Experts has one common goal and that's to play a key role in maintaining the vintage, classic amplifiers, receivers, studio signal processors and tapedecks operating at their best possible levels of performance.

Customers from all over the continental United States seek us out for our renowned attention to fine detail and workmanship.

When we opened our shop to the general public in February 2011, we had no idea how much the market had changed. Many trusted old-timers of the audio repair business had retired or closed their shops, leaving a gap in the service industry for specialized repairs like we do.

Our customer base spans the gamut from serious to casual audiophiles, to musicians and recording studios. One of our strong points being the very reasonable turnaround times for most repairs. We've learned that people are sometimes waiting up to eight or ten months for a repair from some of the shops they've tried. And some customers were greeted with an unfriendly attitude when asking for a time estimate. We don't think that's the right way to treat customers. We can turn most repairs around in a few days to a week, depending on parts availability. And for the "impossible" repairs, a bit longer..

Who We Are


The principal at Amplifier Experts is a retired broadcast engineer. Having serviced, installed and troubleshot the gamut of electronics that puts AM and FM broadcast stations on the air, Mark's familiarity with what makes an audio processor sound a certain way gives him unique insight into how amplifiers sound and what affects sound quality. His experience with designing stereo multiplex generators and audio processors for broadcast applications gives him a unique perspective on how complex systems work. The workings of an amplifier are much simpler.

In 2007, Mark founded a video and sound production company, specializing in producing top-notch audiophile concert recordings. Mark soon discovered that quality wasn't as important to clients as he had assumed.
Thanks to his audiophile blog, a new opportunity would alert him to the changing landscape of the audio repair field. He started getting e-mails from several audiophiles who owned a particular power amplifier that he had blogged about modifying to improve performance in several key areas. At first, he was reluctant to deal with shipping heavy amplifiers cross country, but then one day a gentleman from New York City offered to hand deliver his amplifiers and pick them up the following week, after Mark had performed the upgrades.
It was after this experience that Mark had regained the spark of excitement of working with audio electronics. It was also about this time that he would make the acquaintance of a retired NASA engineer from El Paso, Texas, who inspired the transformation of his shop into the technically-sophisticated facility that it is today.


  • 1960s  -
  • Amplifier Experts owner Mark Weiss has a long and rich history of electronics dating back to the 1960s. Much of Mark's early work was done on the kitchen table and there were no cameras or photos taken, so those days are lost to memory. In 1976, the cellar was partially finished and a concrete floor poured, enabling the set up of a dedicated space for a shop. The shop was then equipped with a Heathkit 0-10 oscilloscope he'd had since 1956. That scope would continue to serve Mark right up to 1982, when he invested serious money for a 'real' 'scope from Hewlett-Packard--a 1740A. Also in use was a Triplet RF Generator, a Precision Audio Generator, a Fluke Power Supply and a variety of other test equipment, bought in the mid fifties.

  • 1970s  -
  • The first amp repair business attempt wasn't a smashing success. Back in 1977, there were lots of repair shops and competition was stiff, so Mark went into electronics, working in optical physics and electronics and the first microprocessors on the mission of automated inspection of web based products.
    By 1979, seeing a need for an affordable multiplex stereo generator for the FM broadcasting industry, Mark designed and built a prototype stereo generator, the first of its kind to incorporate a fully DC-coupled balanced modulator, enabling it to achieve close to 60dB of channel separation across the entire audio band, not just at mid frequencies.

  • 1980s  -
  • In 1982, Mark was experimenting with methods of improving the sound and dynamic range of FM radio broadcasts. He devised a closed-loop system which incorporated an encoder/decoder arrangement and used subcarriers to transmit the side-chain compressor envelope signal to the receiver. A mirror image expander in the receiver decoder read the side chain information from the broadcast compressor, and applied it in reverse, undoing the effects of broadcast compression, while maintaining FCC-legal modulation limits at the transmitter.

  • 2010  -
  • Throughout the years, Mark's career would span the gamut from optics and lasers to data communications. By the end of the 1980s, Mark had ambitions to pursue his interest in graphic arts and for some years into the 1990s, tried his hand at it, with moribund success. By the mid 1990s, a broadcast cluster owner convinced him to work as a contract engineer, servicing broadcast transmitter sites and constructing studios at major and minor broadcast stations throughout New England. After 13 years of contract engineering, Mark had had enough of the commuting, road trips, desolate mountaintop transmitters sites and those emergency calls at 2 am in the morning.

Why Choose Us


There are quite a few shops out there that claim to repair amplifiers. We hear horror stories from time to time about some of them. Their thinking is short-term. We think long-term. We strive to solve problems at the root cause, not put a band-aid on them. Just having test quipment doesn't make for a good shop. It takes experience, intuition and knowledge.


We have nearly five decades of experience in the field of electronics repair and design. Much of that is focused around vacuum tube design, so we're familiar with the unique properties of valve audio amplifiers and the specific criteria and challenges they face.


Today, Amplifier Experts is still largely "the best kept secret", but gaining visibility slowly in the market for musicians and audiophiles. We don't run commercial advertising campaigns, preferring to "bootstrap" earnings into more self-promotion and build business steadily on referrals and customer satisfaction, rather than rude, loud, radio ads.