[mclaren]

I am in the process of buying and trying various 12AU7s (JJ, Siemens, RFT) in my Clarinet and wondered if I should consider options for rectifier tubes as well. Currently I am using a Sovtek 5Y3GT. I would be interested to hear what others are using.

Mike

[Eric H]

I'm using a GZ34, NEC to be specific...  mainly because I had it already and it boosted my voltages up to spec vs. a 5Y3.  I'm not sure how much it affects the sound... 

[ohenry]

Jim wrote the following a while back about the Cornet rectifier.  I'm not 100% that this would apply to the Clarinet.

...The thing with the 5Y3 - design was centered around the Sovtek 5Y3 new production, which happens to be indirectly heated!  It also seems to act more like a 5AR4/GZ34 than a real 5Y3.  So NOS 5AR4 work best as substitutes.  5Y3 has more voltage drop and results in a little softer sound, perhaps warmer.  Not bad, just a little different.  That's the beauty (and curse!) of rolling tubes.  You can fine tune the sonics for your personal taste.  You can make the Cornet aggressive or laid back, punchy or neutral, and can even tilt the tonal balance.

There is no magic combination that works for everyone.  But certain trends are apparent.  The X7s work the tone and smoothness.  U7 the dynamics and slam.  Y3 the weight of tone and bass.  Tube dampers almost always help.

jh

[Eric H]

I should add that the 5Y3's I tried were not the ones Jim specs - they were some inexpensive JAN Philips, I believe, that turned out to be directly heated which I didn't want.  I'd follow Jim's advice (of course)...  and also, stay away from rectifiers like 5U4's that need more heater current.

[amandarae]

Hello guys

My experience concerns the Cornet 2 only.  For rectifiers, I have tried the Mullards (2 ring getter), and Amperex Holland(2 ring getter) except for the fat base and the metal base because it does not fit in the hole of the chassis.  In the 5Y3's, I tried the Sovtek, the RCA ST, the 6106 Bendix, the RFT 5Y3GB, the CBS Hytrom 5Y3GTA brown base, the Allied(Japan)5Y3GT, and the CBS 5Y3WGTB brown base.

For me, the best is the RFT 5Y3GB ST type, followed by the CBS5Y3WGTB of which has the brightest filament light I have ever seen on a 5Y3 type.  Next is the Bendix followed by the Sovtek.  I like the sound of the indirectly heated 5Y3's compared to the directly heated ones.  Maybe it is just me but I also have peace of mind using the formers since it prevents cathode stripping of the driver/amplifier tubes in the long run.  All of which(tubes) are readily available if you search the dealers site.

I am using Tungsram 12AX7's and RCA 5814 12AU7 on my unit which have Mundorf output coupling caps, Sonicap Platinum inter stage coupling caps, Auricap power supply bi-pass caps, Sonicap Gen 2 RIAA caps, and Riken Ohms resistors for the signal path.  All the other resistors are the stock version from the parts list as well as the power supply electrolytic caps.