short article about operating points

[Vinylsavor]

Hi!

There had been some discussions about operating points lately. I also am often asked about 'best' operating points.

So I wrote a short post about my view on the topic on my blog:

VinylSavor: The search for that 'magical' operating point

Best regards

Thomas

[DF96]

Very sensible. Fussy amps are a sign of poor design, not "fine discrimination" as some seem to claim.

[kevinkr]

Thomas, nice article on the selection of reasonable operating points and the rationale behind them.

[mashaffer]

I bookmarked your blog. Very sensible thoughts on gain and headroom there too. I have often thought it rather interesting that we always seem to focus on distortion at wide (maximum) swings. In a sense we are forced into this because of the poor, shall we say, granularity of the plate curves that we have to work with. Where we might typically swing a few tenths of a volt the traces are at one or two volt intervals. If we had detailed curves near our operating points we might see a rather different picture emerge. Having the ability to swing more grid voltage than typical designs allow could provide improved performance just due to the fact that we are swinging very little of the total possible range.

It might be quite interesting to trace our own curves for something like a 6SN7 with grid voltages in say 0.2V steps, assuming we had the setup to do so.

[Vinylsavor]

Hi,

thanks for the kind comments. I'm glad you like my posts. I plan more similar articles about general design philosophies. Planned in the near future are an article about voicing of an amp, component selection and I also plan to write about cable and wire. I guess my views on these topics are quite different from those of most people.

I will also present the first schematics soon. Stay tuned. Don't hesitate to leave a comment on my blog, or ask me here if you have any questions about an article or if you have suggestions for cetain topics which I should cover.

@mashaffer: I actually trace the curves of the tubes I use. This is quite interesting and helps a lot to chosse the right tubes.

Best regards

Thomas