Posts by Donald North

There is an argument that transformer balanced drive separates the left and right signal currents into/out from the headphones, whereas as single ended share a common ground. This is similar to the argument for bi-wiring...

There's a lot of misinformation and misunderstanding about "balanced" amplifiers, which I believe you mean to say differential amplifiers. There are solid-state and tube amplifiers with balanced inputs and balanced outputs but not...

Thanks for these comments. The tubes have 100+ hours on them. The stock Shuguang 2A3s are a little rich and loose in the bass compared to the Emission Labs 2A3s, for example, which sound tighter, punchier and have greater definition....

Hi KingStyles, thanks for sharing your experience with the Stratus at the meet. Which headphones did you use while listening to the amp? If they were using the 1/4" jack, do you recall if it was on the IEC or Low output impedance...

RCA gray plates look similar and are regularly available on ebay and through tube dealers. Perhaps they sound the same.

These specs look reasonable and are similar to the standard 2A3 spec. However, I once had a quad of the AVVT 2A3M with the beautiful blue glass and measured very differently with my Amplitrex tube tester. Under the standard bias...

For rectifier tubes, the U52 is possible consideration.

Are those the dual flat plates? Quote: Originally Posted by drheadphone  I had the HD600 but it was too similar, tonally, to the HD598 which I already had and it had flatter soundstage. The HD650 bests them both...

I plan to attend and display my Stratus amplifier.

Based on the current order list, lead-time for new orders is running around 8 weeks. Quote: Originally Posted by preproman  OK so what's the build time for these amps?