I have the Littledot LD-Y2 300B headphone amp. And the pre-amp tubes are 6SH7, normally with metal shells. They are not expensive, about $5-$10 for a single and $10-$20 for a matched pair. Recently, I have dropped the metal shell tubes a few times to my desk while handling them. Though I can't...

The amp's details can be found here: https://littledotus.com/?product=ld-y2 This is my most expensive audiophile equipment purchase. The humming sounds are driving me crazy. So I tried a few things to diagnose: 1) The hum is NOT affected by the volume knob at all. 2) The hum on the balanced...

I can only afford 1 of the 3 Chinese brands: 1) Little Dot LD-Y2, around $3k. This one uses Lundahl alloy input transformer. But beyond this, I can't seem to be find much information. 2) Original OPA-3A around $3k. This one uses Japanese Z11 transformer. It is also the most compact and techy...

Among the TOTL headphones, many are planars and elecstats, which are known to work better with solid state in general. I could not figure out what exactly those expensive $1000+ tube amps are designed for. Maybe Senn HD800s is the only flagship that is known to pair well with them and it is also...

I adjusted the bias on this little amp. And it sounded pretty good with my Senn 58X and Hifiman Sundara. Now I am looking for some natural next steps during black Friday. My priorities are : 1) Tubey sound, works well with 58X and Sundara. 2) If possible, works well in low gain with IEMs, but...