When the tubes begin to exhibit symptoms such as a dull sound, hiss-noise, crackly, stormy noises, or even total failure, etc. it's time for fresh tubes. The procedure is simple for any qualified person who understands the nature of a high voltage tube device. ONLY qualified personnel should attempt replacing the tubes in our products. It must be done with the unit unplugged from the AC power source and proper procedures followed to insure that ALL high voltage has been drained safely out of the circuit. These are deadly, high-voltage devices, so such care is required.


STEEL GUITAR BLACK BOX  (1) 12AX7 type tube
The tube in the Black Box is a common 12AX7, but it should be noted that we generally recommend using a 12AX7 that does NOT have a spiral filament. Vintage tubes are pretty much fair game as they didn't use the spiral filaments (except for the 7025). However, in 2021 and 2022 due to short supply, we began using the JJ ECC83 (also a 12AX7), and while they do have spiral filaments, we’ve had no problem with them. Tube replacements can also easily be found brand new under the following names/brands:

China or Sino or Shuguang 12AX7 or 12AX7B  
JJ ECC83
TAD 12AX7A/ECC83 Premium Selected (12AX7WA)
Sovtek 12AX7WA, 12AX7WB
Ruby 12AX7-C5
Groove Tubes GT-12AX7-C

NOTE: Steel Guitar Black Boxes serial #s BB5-0471 or earlier used a 12AU7 tube instead. Before replacing the tube, be sure you know which version Black Box you have. 12AU7's are a bit harder to find in a low noise version, but currently we know that the EH 12AU7 and the Shuguang 12AU7 do work well in the Black Box. These Shuguang 12AU7's can also be found under the brand, Ruby, Groove Tubes, and TAD (Tube Amp Doctor). If you’re not sure which version you have or need further assistance, feel free to contact us.


REVELATION TUBE PREAMP  (3) 12AX7 type tubes
12AX7 (ECC83, 5751, 7025, ECC803 or similar).  Tube #1 (far left side nearest the input) requires a certain limited variant of the 12AX7 tube. See the above list for the Steel Guitar Black Box when choosing a replacement tube for the first tube in a Revelation. Tubes #2 and #3 in the Rev Pre can pretty much be any 12AX7 type tube of your choosing. 

NOTE: Early or non-updated Revelations, serial #0111 or earlier will have a different tube in positions #1 and #3 and require a 12AU7 instead. Be sure to check your Rev or give us a call if unsure. 12AU7's are a bit harder to find in a low noise version, but currently we know that the EH 12AU7 and the Shuguang 12AU7 do work well in these two positions. These Shuguang 12AU7's can also be found under the brand, Ruby, Penta, Groove Tubes, and TAD (Tube Amp Doctor). The EH (Electro Harmonix) is also widely available. 


SMS CLASSIC TUBE PREAMP  (2) 12AX7 type tubes
12AX7 (ECC83, 7025, 5751, ECC803 or similar). The SMS Classic uses 12AX7 type tubes. Many are available, vintage used, new-old-stock, and new. Feel free to try the many available options. 


TONIC TUBE PREAMP  (2) 12AX7 type tubes
ECC83, 7025, 5751, ECC803 or similar. Earlier or non-updated versions of the Tonic will have one 12AU7 in there. Please contact us if you aren't sure which version you have. 


V8 - OCTAL TUBE PREAMP (2) Octal type tubes.
We currently ship with the new-make Tung-Sol 6SL7 tubes for both sockets in the V8. If you own an early model of the V8, tube #2 is a 6SN7. Please contact us to confirm. All V8 preamps sold in 2014 and later have a pair of 6SL7 tubes.

REPLACEMENT TUBE UPDATE & ORDERING

There are many tube dealers out there today. Just do an internet search for the tubes you're after. It is a good idea to buy from a dealer that can offer tests for "low microphonics" so that your tubes don't physically make any noise when tapped or don't feed back when in a loud setting. We do recommend seeking out and spending a bit more on vintage tubes. Old USA-made tubes are excellent; they're rugged, reliable, and sound fantastic. You don't even need them to be NOS (new-old-stock). You can find perfectly good tubes sold as UTG (used-tests-good), which are cheaper and virtually just as good as NOS most of the time. If you have trouble finding replacement tubes or have any questions, please don't hesitate to contact us for personal assistance.