I have now worked on two Marshall JCM2000 amps and both are around 10 years old. Both had very similar faults. The fault on both was that the amps sounded “rubbish” and both were cooking the EL34 output valves. Instead of running at about 45 mA of bias current the lowest adjustment you could achieve was over 100mA. recipe for output valve shortened lives and destruction. The fault is clearly in the bias circuit. I […]
A really neat added value benefit of using Tung Sol valves in your amp is their low microphonics. During testing at the factory Tung Sol Valves are tested on a vibrating table to ensure they are not microphonic. Of course this extra testing adds a little bit to the cost. I first witnessed this benefit in my own original silverface Fender amp. Ever since it was new way back in 1970 the amp was always
We have added more new products! We have launched our first group of guitar pedals and effects. They are from Electro Harmonix in New York City. We are an official authorised distributor of Electro Harmonix and to date we have been successfully selling their range of valves/tubes . These are branded Electro Harmonix, Tung Sol, Sovtek. Electro Harmonix have a huge range of pedals and effects. We are introducing the range in phases as it
New Product Line Electro Harmonix Pedals and Effects Read More »
Here is a customer’s feedback on replacing the EL84’s with Sovtek EL84’s. I have only removed the customer name I promised you an update on the Sovtek EL84 valves and how they handled in my Bugera V22. Well I have been using them for about three months now and I am absolutely delighted with the changes they brought to the Bugera Infinium V22’s tone and even ‘feel’. To be frank I have never considered
Matched Balanced Pre-Amp Valves How Are Pre-Amp Valves Matched/Balanced? You might not be aware but no valve manufacturer will test for matched balanced pre-amp valves. So quality valve sellers invest in good quality test and characterisation equipment so that matched balanced pre-amp valves can be identified. This means we have to individually test every pre-amp valve we have in our stock so that we can find the matched ones. This is a slow process as
All of us that have a valve / tube amplifier at sometime find our lovely favourite all valve amplifier suddenly starts blowing fuses. Sounds like a disaster has happened and out wallet is about to take severe damage. Has the amp gone to the great gig in the sky ? A Vox AC30 CC1 blowing fuses was what was presented to me. The Vox AC30 CC1 is a hybrid amp with the reverb and tremolo
I switched on my amp which had been working perfectly the day before. When I used the footswitch to turn on the spring line reverb, strange sounds came from the amp. It was the sound of rumbling thunder with reverb. Not good ! So your first thought is the reverb unit is faulty. Unlikely. My thoughts tuned to the schematic and decided that the ECC83 ( 12AX7) driving the reverb could have become noisy. I
