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I can hardly wait to hear the explanation

"What phono cartridge do you use? If you use one. This is IMPORTANT because the Dyna phono stage is very slew rate limited. I will explain later, if it is useful to you."

Mr. Curl, are you going to weasel out of this?

"Remember slew rate= I/C IF you don't know what that means, then you had better not try to change anything."

Actually slew rate is dV(t)/dt and the specification of interest is the maximum slew rate. What is the maximum slew rate of the Dyna PAS2 phono stage and what is required to accurately reproduce the waveform of a magnetic phono cartridge in the audio passband?

"If you are using a cheapie MM cartridge, its self resonance may be keeping you out of trouble"

Why would that be? Cheap MM cartridges usually have two to three times the output of more expensive ones and since the RIAA gain stage is fixed before the volume control, the required slew rate would be even greater. The resonance peak only makes matters worse because it would give even greater output for the same stylus velocity.

"Audible illusions changed the tube type in order to have more output current available to drive the RIAA caps. The easiest 'fix' would be to add a series resistor to the RIAA network to reduce the load of the RIAA caps.
The second, best way, would be to add a MOSFET follower that would drive the RIAA network.
If you are using a cheapie MM cartridge, its self resonance may be keeping you out of trouble."

Is that how you solve engineering problems Mr. Curl? First find a problem which the user doesn't even know exists, promise him you'll discuss it later, find the most arcane, expensive, indirect ways to fix it which he'll have to do himself but is clearly beyond his skill, and then shove him off a cliff when he doesn't understand your technical jargon?

Cheap soapy dopey nut jack, in the unlikely event you feel you have a problem with the RIAA gain stage of your preamp, the best way to fix it is to buy an inexpensive outboard phono stage pre-preamp or use the tape outputs of another preamp or amplifier whose phono stage you do like and connect it to an unused high level input on the Dyna preamp rather than try to redesign the Dyna circuit you obviously are not qualified to touch. There are plenty of them around for well under a hundred dollars, it will work without a doubt, it will only take a few minutes to install, you won't wreck your Dyna preamp, and you will have money left over to buy some overpriced audiophile cables to hook it up with.

Mr. Curl, why would an MC cartridge be a problem other than the fact that the Dyna preamp doesn't have nearly enough gain on its own?

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