So, my backups of a very special tube got delivered early and ended up showing up yesterday afternoon, and it's time to let the cat out of the bag. I have found a very special driver tube, that is hands down the best 6SN7 I have ever heard. Go figure the tube was made in Germany, and it sounds a lot like the Elrog's.
Say hello to the RFT 6SN7 from the 50's.
There are several slightly different versions produced in the 50's, and I currently have two of them so far, and they both sound the same. My first pair from 57' pictured above, has ceramic spacers instead of mica, with a single foil getter.
My 2nd pair pictured below has mica spacers, welded plates and a dual foil getter from 55', and sound just as amazing as the first pair.
I also have 2 more pairs coming (one of them pictured below), that have the ceramic spacers, dual foil getters and welded plates from 54', and I imagine they will sound just as amazing as the first two pairs.
I first discovered RFT tubes while rolling 12AX7, 12AU7, 12AT7 tubes with my previous amp (Pendant SE), and I became so enamored with their sound, that I told others about them and many ended up finding them to be game changers and a step above most other tubes in the family and are still using them. I would describe the RFT "house sound" as being pretty much spot on with how people are describing the Elrog "house sound", as in being extremely dynamic, transparent/detailed, with a hint of warmth, killer texture and extension on both ends, and a massively deep and holographic stage. The interesting thing about my first pair of RFT 6SN7, is that I have been watching this pair for over a year now on eBay, and I started watching them once I realized how incredible their smaller 9 pin noval tubes were in the Pendant, and I knew I just might own another amp that used 6SN7's some day, so I continued to watch them and hope they still might be there when I got back into that tube type. So, the second I placed my order for the HA300mk2 a few weeks ago, I went on eBay to my watched list, and to my surprise the RFT's were still available, so I bought them without a second thought, and they sure did not disappoint.
I have read a ton of info on the famous Melz 1578 hole plate, and from what I gathered the RFT has a similar type of sound, and I would love to hear them back to back, and my money would be on the RFT. A big thing going for the RFT is reliability and build quality, and I have read countless post about the inconsistencies with Russian tubes, and how they often have quality control issues (mainly bad soldering of pins), so I am glad the RFT are living up to my expectations sonically as well as knowing they are tough and well built tubes as well.
If you want to hear what the HA300mk2 can really do, I highly suggest hunting down some RFT 6SN7's, and pairing them with some Elrog ER300B, and then top that off with a quad of some G.E. 22DE4, and you will basically be tripling down on the sound being extremely dynamic, transparent/detailed, with a hint of warmth, killer texture and extension on both ends, and a massively deep and holographic stage.
Happy Hunting, Rolling and Listening!
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