VTA ST-70 How Does it Sound w/ Various Levels of Negative Feedback? Listening Tests w/ Pedro Diaz

In this video I bring the VTA ST-70 over to my friend Pedro's place for a critical listening test. We hook the amplifier up to a pair of Quad ESL 2805 speakers and analyze what we hear while changing between two negative feedback settings. We find that we both prefer more negative feedback in this specific system. We also discover that it was very difficult to hear any difference between 40mA and 50mA bias levels. Come along with Pedro, Dolly (Samoyed) , and I as we learn if what we found during bench testing in previous videos tracks with what we are hearing.

Pedro's Youtube Channel:

   / @deaudiofilosylocos  


Previous VTA ST-70 Videos:
Orignal vs VTA:    • Dynaco ST-70 Original vs. VTA Bench & List...  

Negative Feedback Experiments:    • Dynaco VTA ST-70 Negative Feedback & SS Re...  

Bias Experiments:    • Getting the Best THD Performance Out of Yo...  

00:00 Introduction
00:26 Who is Pedro Diaz?
01:12 The Setup
02:51 Initial Impressions
03:22 Bill Withers - Just the Two of Us
04:26 Vivaldi Violin Concerto in E minor
05:36 Respeghi Fountains for Rome 3rd Movement
07:24 Summary of Listening Tests
08:33 40mA vs 50mA Bias
10:17 Janis Joplin Mercedes Benz
11:07 Bonus Testing Fun