Dynavector XV-1s loading question.

Oooo ... wait a minute! I re-visited items 1 & 2 (resonant tank circuit).

The formula for resonant frequency is given by:

res. freq. = 1 / [2 * pi * sqrt (L * C) ].

I believe this is the net capacitance, but what I'm not clear on is whether the resistive load is taken into account - whether we're talking about the net capacitance as defined by the RC circuit (including the resistive load), or whether the only effect is the raw capacitive elements - without taking the "R" (resistive load) into account.

I believe it takes the resistive load into account, but perhaps Ralph can answer this question for us.

Cheers,
Thom @ Galibier

The formula for resonant frequency is given by:

res. freq. = 1 / [2 * pi * sqrt (L * C) ].

I believe this is the net capacitance, but what I'm not clear on is whether the resistive load is taken into account - whether we're talking about the net capacitance as defined by the RC circuit (including the resistive load), or whether the only effect is the raw capacitive elements - without taking the "R" (resistive load) into account.

Thom, I believe that the resonant frequency is determined purely by L and C, per the equation you cited. R will affect the degree of damping of that resonant peak.

If R is very high, say 47K, that peak will be relatively large. If R is excessively low, the low pass filter formed by L and R will cause the overall frequency response to roll off before the frequency of the resonant peak is reached. If R is optimal (with respect to damping of the resonant peak, which may or may not be optimal in terms of overall system synergy), then the response will be essentially flat up to the area of resonance, and above that frequency a smooth rolloff will occur.

As you aptly stated, "'just enough' is always the best solution."

Great thread, btw!

Best regards,
-- Al

Thank you Jonathan for furthering our collective thinking on the subject; yet more food for thought. Thank you Thom and Al for nudging resonance a bit more forward as it relates to this topic - now we know just how much of a "tuned circuit" the whole analog front-end really is! Cheers,

-Richard

Tuning - reminds me of one of my other loves - guitars.

As it applies to analog, I recall an instance at a music shop where the mother wanted to return the guitar she bought for her son ... because it was out of tune!

Fortunately, our analog front ends are more stable than that (grin).

Cheers,
Thom @ Galibier