Following our blog on testing the 6L6 and the El84, we have now done a burn test on a JJ El34. Â The test got delayed as our Avo Mk2 tester developed a fault with a worn out “backing off” Â pot and I had to come up with a good repair not having the benefit of any replacement part. I guess this part has not been made since the days of Harold Wilson being Prime Minister […]
I was curious to see if there was any information on the net regarding the noise figures for any noise measurements on preamp valves Noise is just one of the many things to look at in selecting a good valve for your amp and I thought it was worth taking a look at this. Noise measurements on pre-amp valves  requires building some specialist test gear so I thought I do some research to find information.
Here is a guide to Pre-amp Valves There are many types of pre-amps around all with the same pinout and if you are not a valve geek like me then how do you work out what is best for you? I had a nice customer highlight this to me and I thought it would be useful to make some notes which may help you choose the right pre-amp valve especially for the V1 position in
Having done a long term test on a JJ Electronic 6L6, and saw that the cathode current remained rock solid over over a period of 48 hours the next valve to be tested was the EL84. Â The reason for running the valves from new over a period of many hours was to see if burn in provided any advantage when doing matching. EL84’s are used in many amps such as the Fender Blues Jr, LazyZ
EL84 To Burn in or not to burn in that is the question Read More »
A number of valve sellers offer output valves that are “burned in”. Burning in valves means basically running them for a number of hours. It is claimed that the benefit is that this weeds out the ” weak valves” and improves the matching of the valves as the implication is that the valves go out of matching if they are matched from new. I was suspicious of this claim as there is no data produced
A new valve has entered production. The JJ Electronic 12BH7-A has been introduced. It has been in development for a good number of months and now first production is being released. One other supplier  has been making new 12BH7’s but were always difficult to get into stock.  So the JJ electronic 12BH7 -A version is a welcome addition from a trusted European valve manufacturer. We are official authorised dealers for JJ Electronic. We have the
JJ Electronic 12BH7-A Brand New Valve from JJ Electronic ! Read More »