From: martin@rakupottery.org.uk   
      
   On 2017-04-22, Frank Lucas  wrote:   
   > So I've decided to buy two brand new JJ's GZ34 for my two mono 2A3 amps.   
   > JJ's are cheap and I thought that if they were to last a few months   
   > before selling the amps they were good enough.   
   > I replaced the old chinese Golden Dragons (5AR4) and everything worked   
   > flawlessly. The sound was a bit thin but I thought it was just matter of   
   > waiting a few days for the tubes to express themselves better.   
   > Then when I was going to leave everything as it was and replace the amps   
   > with the love of my life the Dynaco ST35 ...   
   >   
   > A friend stopped by with a bag of old Mullards GZ34 to put in those amps   
   > and the something really strange happened.   
   >   
   > I always prefer double blind testing, I'm an atheist, I don't believe in   
   > cable magic or snake oil or in Bolduc's mystical runes and I trust my   
   > ears more than my eyes.   
   >   
   > The difference between the sound with the JJ's and the one with the   
   > Mullards is so clear that even being in another room you could feel the   
   > change. Dynamics, bass response, sweetness ... I was stunned.   
   >   
   > The difference when we tried to swap the humble Guiguang monoplate 2A3Bs   
   > with the pricey AVVTs was almost inexistent apart from the latter being   
   > too metallic and so the worst of the two. Great difference was achieved   
   > instead when we tried a couple of Marconis NOS.   
   >   
   > Further investigation with the use of a scope and a signal generator   
   > showed that with the Mullards the sag was less and recovery was faster.   
   >   
   > Would a couple of solid state rectifiers with a properly calculated   
   > series resistances and maybe a standby switch act better than the mighty   
   > Mullards?   
   >   
   > The 35 is still on a shelf waiting ...   
   >   
   > Are there any brand of GZ34 or 5AR4 that resemble the sound of the   
   > Mullards or in other words that act electronically like Mullards?   
   >   
   I cant answer that question but I am interested because in the 60's   
   in fact from 65 to 71 I worked in the Mullard stores in Mitcham   
   where lorryloads of valves used to come in unmarked, apart from   
   a datecode round the base, which i dont remember any more, we always   
   knew they were the best. THe only equivalents in those days were   
   Russian valves, which were used in some marine equipment.   
   I has been interesting reading these threads, and i still have a   
   copy of Radio Valve Data from 1961.   
      
   --   
   Martin   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)