Worked grea, and is still working 4 years later. It has less soundstage than the stock one that came with my Schiit amp, but sounds more focused.

This tube was purchased to replace the stock tube that came with my Vali 2++ headphone amp, which is part of a Vali 2++ amp and Modius DAC stack. When I got this setup, using 96/24 content for reference material, I had a hard time discerning the difference between my computer onboard audio (Asus ROG SupremeFX Realtek S1220A) headphone output and the Vali2++/Modius headphone output. There was a difference but it was very subtle. After overcoming a tube compatibility issue, detailed below, I performed the same A/B test between the onboard audio and the Vali 2++/Moduis. The difference was unbelievable. So much so I am shocked that Schiit Audio does not offer this tube as standard or at least as an upgrade.The noticeable changes were: greatly expanded sound stage, fuller bass without being distracting, very detailed through the vocal range, and clear highs. It is difficult to separate the effect from "uncovering detail in the source material" with "adding color and tonality overlayed on the source material, which sounds pleasing". I think tube is adding both, and the effect to my ears is remarkable. One way to describe the effect is: the stock amp and onboard audio clinically reproduce the original recording whereas adding the 6922 EH transforms the recording similarly to a great remaster from the original recording. The song is the same, but the auditory experience is shockingly enriched.I came into this upgrade expecting a small improvement in sound, perhaps more articulate reproduction of mid frequencies over the stock amp. What I received, for a modest cost upgrade, was a completely transformed audio experience that has me discovering details of long enjoyed songs that I have not noticed previously. The effect is small on lower production quality recording, but still present.------------------------------------------A tube converter was required to provide compatibility for popular 6922 tubes with my Schiit Audio Vali 2++ amplifier. Search for "6922 6N2 ECC88 E88CC (Top) TO 5670 6N3 369A (bottom)" for tube converters to allow use of Electro-Harmonix 6922 EH tube with Vali 2++ and Vali 3 amplifiers.------------------------------------------Schiit Audio changed the tube compatibility of the Vali headphone amplifiers between the Vali 2+ and Vali 2++ models. The following tube compatibility information was verfied with the Vali amplifier manuals:Vali 2 / Vali 2+------------------uses 6DJ8, 6922, ECC88, 6N23P, and 6BZ7 tube typesVali 2++ / Vali 2++----------------------uses 6N3P, 2C51, 5670, and 396A tube typesThis change in tube compatibility is not well communicated. when I had first installed a new 6922 tube, the tube heater glowed, but no sound was output. It was only after researching how to troubleshoot tube amp output issues that I found the difference in tube compatibility.Schiit Audio does not appear to have updated the external case labeling of their Vali 2 amps, as all versions labeled Vali 2; regardless if it is a 2, 2+, or 2++. You have to look at a small sticker on the back of the unit, beside the power switch, to determine the specific Vai 2 revision. Hopefully this expanded explanation will be helpful for others.

Installed in a Grant Fidelity Tube DAC-11 that serves as a preamp and headphone amp. Let it initially idle for a few hours then played a Mozart Oboe concerto…..sounds very nice. Brite and clear but not at all harsh or brittle. Lows and mids are full and pleasing.I would recommend this tube as a daily driver without hesitation

Danke

Tube sounded great at first. After a few months of usage I started getting an audible ringing/feedback sound. I did narrow down the sound to the tube, so I'll have to get a replacement from another company.