***DO NOT OPEN UP YOUR BENSON TUBE AMP OR REVERB UNIT UNLESS YOU KNOW WHAT YOU ARE DOING. THERE ARE DANGEROUS VOLTAGES INSIDE AND THEY CAN HURT OR KILL YOU. SERIOUSLY, DON'T OPEN IT UNLESS YOU ARE A QUALIFIED TUBE AMP TECH***
This page is intended for general information about care for your Benson product.
If stainless steel (used until 2017), use a microfiber cloth and carefully apply either WD40 or Mineral oil. Wipe off until all dirt and remaining cleaning agent is gone. This will restore shine and take of fingerprint marks, etc. If aluminum, just use a little soap and water.
Use a clean cloth and water. For the lacquered ticking, shine can be restored using a chamois cloth to buff the surface lightly.
Always replace tubes with the same type (12AX7, etc) and in the same locations. The order of tubes is written on the mattress tag on the back of the product. No biasing is required in the Monarch, Tall Bird, Vinny or Chimera, but it is required for the Gnostic. DO NOT turn the trim pot inside the Monarch or Chimera—it is an internal adjustment set at the shop, and your amp will not sound right if you do.
As a general rule, replace tubes if they become microphonic (it sounds like tapping on a microphone if you tap them gently with a pencil while the product is on). Power tubes should generally be replaced ever year with regular use. Preamp tubes last a little longer... I would expect them to last about three years with regular use.
I use, and like, JJs. The amps are designed around JJs. NOS tubes might sound better, and they might sound worse. If you replace the tubes with NOS, be prepared for the possibility that you not be immediately catapulted to tonal Nirvana. When the circuit is right (and we do our best to ensure it is) your Benson is going to sound better with regular tubes than a lot of other amps are going to sound with unobtanium 1950-something rusty pin 12ax7s.
If Something Doesn't Sound Right
It probably isn't. Turn your amp off immediately before something else is hurt. Take note of what you observed. Did the pilot light dim? Did the tubes glow bright red? The good news about our amps is they can always be fixed. They are built simply and are literally just a collection of easily replaceable components (by a qualified tech). Some solid state amps and even tube amps are an almost immediate throw away when they fail due to the design... ours are designed by a long time amp tech and meant to be serviced easily and cheaply by your local tube repair guy.
If your amp qualifies for warranty, get in touch with us. Any amp ordered after April 2nd, 2015 has a two year warranty limited to non-tube-failure issues. We will ask you to ship the amp to us, we will fix it and determine if it is a warranty problem, and then ship it back to you. If the problem is not under warranty due to abuse, tube failure, modification, after the two year period etc, we will charge for the repair and return shipping. Our rate is $60/hr plus parts to repair Benson Amps out of warranty.