Looking for a softer tube

NOS RCA 12au 7 Black top or clear top will work, and they are not as expensive as Mullards. I also believe their softer. In no way am I knocking Mullards, just differentiating.

You might try a 6211 if you can find them. It's a lower gain 12AT7. I'm also with the Mullard guys as far as finding them to be warm.

Siemen e82cc/12au7. It has a vivid and clear midrange. Excellent dynamics and a controlled top end. Check Upscale Audio for exact description.

I will be selling my backup MQ in platinum grade that I no longer need and was purchased from Upscale.

BTW, Philips e88cc SQ is one of my favorite tubes.

Siemen grey plate 12au7,find them buy them fantastic detail and midrange they let the music come through.I had to replace my telefunkens which are very smooth almost to smooth in my system but may work for you I just cannot pass up the midrange of the siemens.