Bottlehead Forum

Bottlehead Kits => Legacy Kit Products => Paramount => Topic started by: rbc3 on March 10, 2015, 12:02:41 PM

Title: Do Paramounts need a matched pair of tubes?
Post by: rbc3 on March 10, 2015, 12:02:41 PM

Are there any benefits/advantages to having a matched pair of 300B output or 5670/2C51 input tubes for Paramounts?

Title: Re: Do Paramounts need a matched pair of tubes?
Post by: Paul Joppa on March 10, 2015, 04:21:46 PM

Are there any benefits? No, I don't think so. You might hear a difference between a new and very old (heavily used) 300B, but if they have similar history I doubt anyone could hear any difference at all.

The 5670 uses the two sections very differently, so there is no point at all in matching the sections. The shunt reg half is dominated by the 431 chip, and the driver itself has a bias trimpot so you can set its plate voltage exactly.