[5] So far so good, made the sound warmer.

[5 V] Great tube for rode k2

[5 V] Love these tubes. I replaced my Gold Lion Genalex EC882/6922 tubes with these Telefunken tubes and that added a warm tone which I really love.

[5] These are awesome tubes, if you’re looking to warm up your sound with big low end and smooth mids and highs, this is warm up galore. Very colored, great for tracking. These went on a ART PRO VLA II, and they did loads of justice. Dont forget to get a matched pair for stereo recording. Using with drums, keyboards, acoustic guitars, voice

[5] My 1991 Peavey AMR T-9000 tube microphone has always had a Peavey 12ax7 in it...and it sounds good. However, I'm always curious what other tubes sound like in it. I have tried several different tubes and been disappointed every time. Muddy, too bright, too noisy...none were as good for this mic as the Peavey...until I tried this Telefunken. OMG...my mic came alive in a way that I could have never imagined. Warm, clean,loud and low noise. I highly recommend this tube !

[5] very good service also

[5] I am using the Telefunken ECC83-TK/12AX7 in the v1 position in my bass preamp. It has a smooth bottom and mid-range without being too bright and harsh at the higher frequencies. Sounds nice with my 4003 Rickenbacker.

[Octal] I bought it for my Schiit Vali 2+, I find this sound very close to Siemens E88CC where it's a very balanced tube across the range with punchy bass. Most tubes I come across are somewhat soft in their bass presentation (i.e. Tesla E88CC). This tube also has decent sound stage and separation.


However the only con I would say is that this tube in general has more of a solid state kind of sound signature as oppose to tube sound. Though it could also be Schiit Vali+ own signature influence over it, I'm not too sure.


But overall a very nice tube for the price, highly recommend!


The other con that's not really a con is that, the box it came with has a drawing that looks a bit like a condom. I guess it's carried over from the 1970s or something like that. Just thought it's a bit hilarious.

[Octal] I purchased these tubes to replace the stock tubes in an ART Pro MPA II, and they are exceptionally smooth, turning a chevrolet into a mercesdes basically. The unit now sounds like a 4 figure higher end pre amp.

[5] If you have an audio system that is capable of displaying the difference, these are much above the $19 version of this tube. I have a Magnum Dynalab MD809t internet tuner that features a 4-tube push-pull output which came equipped with the lesser-costing version of this tube; after replacing them with the Black Diamond series I hear a distinct difference in audio quality. It's nice to get back to the warmth and depth of sound that distinguishes tubes from transistors. With these Black Diamonds there is no tube hiss or hint of distortion -- it's vintage wine for the ears!