RCA 12au7 Clear Top Posted on March 6, 2012 by tubemaze (32 votes, average: 4.25 out of 5)Loading...“A bit fuller, richer and a bit more vibrant than the RFTs, not clinical, but still good detail. A more traditional NOS sound.” Read“if you have to use a 12AU7, then the cleartops are quite good. “ ReadShare this post:
There have been a lot of posts about this tube. In summary, this tube is great and sounds fantastically. One warning, if your system tends to be bright (you have titanium or aluminum tweeters), this tube could make some songs sound excessively bright. Overall, this sounds as good as 5751 (my reference tube) in Dared VP-300B amp.
Now, I’ve tried this tube in Dared and MC instead of 12ax7 in both phase inverter and preamp stages. All of it sounds great. Very nice tube – is it as good as Telefunken or some other leaders in the group – I would say so, but for the price it’s a tremendous value. Stack up on the tube while it’s freely available – I have 15 and counting.
Tried in in Bottlehead Crack. This tube sounds quite nice compared to many other 12au7 tubes, but can’t compare to Tung-sol Black bottle. Issue here is high frequency. In my amp, it was just way over exaggerated, which leads to tiring after a bit. Even with Sennheiser 650 which has very sweet highs, it’s still very pronounced. It might sound good in the older gear, which sounds too warm to begin with.
I had these tubes in my preamp and wasn’t impressed. I mean they are clear and such, but sound stage was OK. Highs were sharp.
I received a matched quad of the RCA clear top (organ issue) and was very impressed at first. It’s a really solid sound with meaty and rich bass, and nice soaring highs. Right when I plugged them in the music jumped out of the speakers. It’s ironic because it has a classic american attitude – in your face.
A little fatiguing after a while and maybe a little bi-polar (mid-range seems to get left behind a bit). I know it’s a very “beloved” tube, but from my experience I’m not sure it quite competes with the big players in areas like refinement, beauty and magic…
RCA Clear Tops (Organ Issue, Side-Getter) – 4 Stars