We have broadened our range of EL34‘s in our store. But which one is best for my amp? This is a handy quick guide to EL34’s We now have :- JJ EL34 JJ EL4 II JJ EL34L EH EL34 Tung Sol EL34B We offer all the above in matched pairs and quads. The EL34 was one of the last additions to the audio valve market and it was introduced by Mullard in the early 1950’s. […]
Which EL34 ? We explain differences on selected types Read More »
Another Fender Hot Rod Deluxe arrived . This was one of the early ones in really nice physical condition dating from around 1998.  It was made in the USA. Alas, I only ever see sick ones. This one had about 0.2 watts out on full volume and totally distorted. The valves had not been changed in years and the output valves were original Sovtek 5881’s rebranded as Groove tubes. They were still kind of working
The Fender Blues Jr is a popular amp. It has enough power with 15 watts for small gigs and it does have the Fender tone with a hint of “Britishness” with the EL84 output valves. . The reverb circuitry is solid state and three 12AX7’s for the pre-amp stages. The 15 watts comes from a pair of EL84’s feeding into a 12 inch speaker. The amp is constructed on printed circuit boards. One holds the
An ART Pro MPA II Tube Microphone Amplifier arrived for repair. This two channel unit uses two 12AX7 valves. They are made in China. The fault was blowing mains fuses. I dismantled the unit and was very surprised to see that the power switch does NOT isolate the 230volts AC mains. It only switches on and off the low voltage to the main board !! The transformer is connected permanently to the mains no matter
ART PRO MPA II Tube Microphone Amplifier Safety Concerns check this out Read More »
A Fender Hot Rod Deluxe arrived that was not well. These 40 watt amps sound pretty good when they are working. However, a number of faults appear as they age. The obvious fault was that the 6L6’s were worn out. They were dull and noisy. However I could only find this out when we got the amp to make some sound ! When the back was removed one of the output valves was not lighting
I was repairing a Bugera 333 amp which was really badly crackling. Taking the back off the amp revealed cooked EL34’s. This is a 120 watt combo amp. A gigging amp will be used at higher volume settings and so the output valves get worked hard. In a high power combo amp the valves are exposed to a lot of vibration from the cabinet. This is exactly what they dont like. This amp can use
Using Your Ears to Test Your Output Valves and Bugera 333 info Read More »