General Questions

Technical Support

Audio Research dealers are the first line of support to solve your technical issues and provide necessary service. To ensure safety, proper diagnosis and to preserve the sonic quality of your Audio Research equipment, maintenance, updates and/or repair work should only be performed by an Authorized Audio Research Service Technician.

An Authorized Audio Research Technician understands and knows the ins and outs of your unit. With this knowledge and proper diagnostics equipment, they are able to provide quality diagnostics and repair services.

If you need service, you can take your unit to your local dealer or send it to Audio Research.

To send your unit into Audio Research for updates, maintenance and/or repairs. Go to to submit a “Consumer Service Request” form and ship your unit to us.

Service and Repairs Performed by Audio Research

Audio Research can service most of the models produced in our nearly 50-year history. In-house repairs are performed by our skilled authorized service technicians, who have a comprehensive knowledge of Audio Research products. Our rigorous repair process ensures that repaired products meet or exceed their original published specifications.

Due to the complexity of servicing these sophisticated electronic instruments, we are not able to provide repair quotes before fully diagnosing the equipment in question. The Audio Research service labor rate is $130 USD hourly.

SE Updates Available

SE updates in North America must be made at our facility. When a unit (or monoblock pair) is received for the update, it undergoes a comprehensive checkup that is handled with great care:

• The unit is partially disassembled

• The SE updates are installed

• The unit is reassembled and new tubes are installed as appropriate • Each unit is bench tested

• Burned in for two days

• Bench tested again

• Listed to in a reference system before it is packed and returned to the owner


SE products updated by Audio Research will also receive a one-year warranty, 90-day on tubes.

REF75, REF150, REF250 and REF750 Amplifier SE Updates

In addition to changing from the KT120 to the KT150 output tube as part of a complete set, there are a number of active and passive part changes in the SE amplifiers that result in major sonic improvements. Very simply, the SE amps are dramatically better in every way: purity and lack of grain, resolution, micro-and macro-dynamics, more holographic with better focus, phase and Dme coherence, and greatly improved bass weight, authority and control.

REF5, LS17 and REFPHONO2 SE Updates

The REF5, LS17 and REFPHONO2 updates include: New front panel with round metal buttons and new capacitors. The REF5 and REFPHONO2 updates also include one new side panel with an additional power supply board attached, new internal wiring, and a new 6550WE tube in the power supply.

Other Updates

Owners of Audio Research SP3 preamplifiers have the option of updating to the SP3C. The SP3 was introduced in 1972 and was instrumental in establishing Audio Research’s worldwide reputation for sonic excellence. Several thousand were sold during the period of 1972 -1976 and most, we believe, are still in service today.

This SP3C update is an extensive upgrade providing significant improvements in sonic performance, reliability, and usability. You will find the bass will be more defined and extended, the midrange smoother and more accurate and the high-frequency range is further extended and more neutral. For those who like classic tube sound, this modification takes a large step toward accuracy while preserving the SP3’s overall character.

We are also offering power supply updates to PH7 and REFCD7 models that have three 6H30 tubes in the power supply.

The VT80SE and the VT80 are of the same design. The SE designation indicates that it is being used with KT150 output tubes, not the KT120s that the VT80 originally shipped with.

The VSi75 was released with KT120 output tubes. A running production change was made switching to the KT150 output tube and lowering the main board to accommodate the height of the taller KT150s in the tube cage. For customers using the VSi75 without the tube cage, no change is necessary to use the KT150 output tube.

Note – We do not perform any previously offered updates not listed above or custom modifications.

Interested in an update?

If you are interested in having your Reference amp updated please contact your Audio Research dealer or [email protected] for pricing information.

To be notified when updates become available for your current or legacy Audio Research equipment, subscribe to our newsletter. Note – For amplifier updates owners will receive the complete new tube set as part of the SE update.

Only units in good working order can be updated. Any functional problems need to be addressed before the update can be performed.

Parts Orders

A number of user-installable parts are available from Audio Research. Tubes, manuals, fuses, top covers, power cables, and other parts are available to owners. Please contact your dealer or email [email protected] to inquire.

Note – Electronic components, service documentation/schematics, and internal parts are only available to Authorized Audio Research Service Technicians.

Replacement Remotes

Yes, we do have replacement remote controls for many of our past and current models. If you are interested please contact your Audio Research dealer or send us a message at [email protected] for pricing information.

Models no longer serviceable

The Audio Research products listed below are NOT serviceable because parts no longer available.

• Some D-Series amplifiers

o D52/B

o D60

o D100/A/B

o D110/B

o D111

o D120

o D350/B

• HD220

• SD135

• CD2

Tube life

Tube life will depend on several parameters: product type, how the product is installed, loudspeaker efficiency, room size and acoustic damping, listening habits or average sound pressure levels, A.C. line stability and purity, manufacturing conditions, and other circumstances. Recommended tube replacement intervals:

Preamplifiers & Source Components:

Small signal tubes last up to 4,000 hours, regulator (large power) tubes last up to 2,000 hours.

Power Amplifiers:

Output tubes last up to 2,000 hours, with the exception of KT150s, which last up to 3,000 hours

Note: Near the end of the tubes sonic life, ageing vacuum tubes may degrade the sonic character of the product(s) they are used in. Make sure to replace your tubes before outright failure occurs. We stock vacuum tubes and match sets to the specifications of each model. Audio Research tubes undergo thorough testing prior to being selected for use in our equipment. To order replacement tubes please contact your local dealer or send us a message at [email protected] for pricing information.