Tag: LL1671

4P1L driver – LL7903+LL1671 tests

Last week I did some preliminar tests with the LL2746 in 1:2 step-up mode.  Despite having measured good results with it, it will be a challenge to drive grid current given that the output impedance of the 4P1L will be multiplied by 4 so about 5KΩ.

Before looking at the LL1671/20mA which is suitable for multiple driver valves, let’s see how the LL2746 driver performs with the addition of the input step-up microphone transformer LL7903. I’m currently using the LL7903 in my 814 SE A2 amplifier and sounds really nice. The LL7903 was wired up in 1:4 setup so gain can get about 63:

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4P1L / 6C6C SE Amplifier Design

Pushing to the limits

Weight lifting

 

 

 

 

 

 

 

We’re constantly obsessed to get the most out of our lives. Not a product of the capitalist world we live in, but a fact of our human nature. Its evolution.

When it comes to sonic power, unfortunately we are not too distance from this thought. We want more Watts. Yes, pure power. My generation back in the 80s got misled by the audio product marketing and their unrealistic metrics (e.g. PMPO)  to fudge the real power of a solid state amplifier.

Continue reading “4P1L / 6C6C SE Amplifier Design”