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Merry Christmas James! I have done extensive "time" (spelled $$$) rolling tubes in my M901 and always always come back to the Sylvania GB-5751 Gold pin.It is my favorite tube for what I would call moderate to low level critical listening.I also had used a couple of the Psvane AU and AX series tubes with had very nice qualities as well as a JAN 5751 garden variety.However the one tube which has found a permanent spot in my system is the Sylvania Gold Brand 5751 .Have a wonderful day of faith, family anf fun.Tom
Yes. Grant Fidelity periodically has them on sale. Also, since they are sold only as pairs, folks who only use one often put the other up for sale.
Hi Dave, From what I read on the Dodd buffer site ( http://doddaudio.com/BatteryPoweredTubeBufferPreamp.aspx ), your buffer uses battery power and it is designed for 6DJ8 (6V) tube. I don't know if you should have used 12AU7 (which is not substitute for 6DJ8 or 6H30). Please check with the buffer manufacturer for compatibility and if any circuit change is required.It's almost next to impossible for both small signal tubes develop noise issue at the same time. So I think the chance is that you are having a equipment matching issue somewhere.Unless the tubes are defective, we cannot take returns but we can provide replacement for another model if the other model will be used in the right substitute. Of course the returned tubes have to be NOT-damaged by improper use. Microphonic could be an issue for a tube, but what you described is definitely not micro phonic. And 12AU7 is not a direct replacement of 6DJ8 or 6H30 on your buffer.
I purchased a set of Psvane 12AU-7T and I get a wind sound independent of the volume or input controls. I tried both tubes with the same results. The stock tube is dead silent. I am disappointed.
I have two sets of Psvane 12AU-7T and a set of Psvane 12AX-7T and while their is a very slight hum if you place your ear directly against the tweeter there is no sound that can heard while listening. Not as black as the Sylvania Gold Pin but most definitely not audible from 3-6 feet away. I am listening to them right now. Definitely in my top three or four favorite tubes behind the 5751- gold pins and 50 year old Mullards.I use the 12AX7 in my Grant Fidelity tube CD as well with just awesome results.FWIW since my cap upgrade to Clarity's I have been bypassing my buffer a lot.
@Trismos -The 12AU-7T Tube is on Gary's list of tubes that will work with buffer in the Sensation. I am running the Psvane 12AX-7T in my Sensation, that also has the Clarity caps. I am switching back between 101db efficient ZU AUDIO Soul Superflys and my Strada Minis with 88.5 db efficiency,the background is dead silent and the sound is fantastic. The Dodd Buffer and in line Buffer on Gary's site both use the 6dj8 tubes, I think that's where Ian got the idea that the tubes were not compatible.
Hi Dave,Most of the posts are referring to the 12AX7, not very often a 12AU7 can be changed in the same circuit as the gain is only 30% of the 12AX7, and guess what, they are noisy when things aren't right. I'd be asking Todd what tubes they recommend in their gear, the 6H30DR supertube would be my first choice, although they are $200 each, we have a limited supply of those.If you had asked us if a 12AU7 is a drop in replacement for a 6DJ8 we would have said no, ditto the 12AX7 Cheers,Ian
I have a Sensation M451 w/ Tube Buffer, Sonicaps & Platinum bypass cap., batteries, jumpers set to full range. Amp drives 91 db eff. GR Research N3's. The Psvane 12AU-7T tube is very quiet w/ a nice black background. My Sylvania 5751 gold pin gives off more tube hiss than the 12AU-T7. But in both cases, I need to get my ear close to the tweeter to hear anything.
gary dodd made available the option of using 12a_7 tubes or 6dj8 tubes in the virtue audio tube buffer. find out which one you have. what stock tube did yours come with?
Maybe I should leave well enough alone and not buy into the expensive tube hype.