MPP

Also having a load of BF245C will they be acceptable to sub J310 as the error amp's active load in the reg and in other places in the phono maybe? They would need some Irish dancer feet bend but they pay in noise figure.

Yes that will works just set the resistor for 1mA (about 1K from the datasheet ID 1mA at VGS 1Volt). This is not very critical :)
 
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The CCS uses one Led as an reference and the CVS that feeds the CCS uses two Led's as an reference, that makes that optimum regulation is lost when the CVS looses it's headroom. If you give the CVS 2Vols headroom, then the minimum DC-in would be "DC-out + (2 * Led) + 2Volts headroom" = "18 + (2 * 1.7) + 2" = 23.2 to this we have to add the 'ripple-floor' of the raw-input-voltage (lets say 1Volt) and we get at "23.2 + 1" = 24.2Volts minimum input voltage (when using 1.7Volts drop on the Led).

Here is the schema including some of my notes.
 

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Some may be tempted to pre-reg this so to be care free of mains tolerance without secondary over-spec and extra sink heat. But I would be cautious of unstable interaction with the CVS. Hiss would be the clue if not having a scope.

You are right.

The PSU is designed to be connected to a filtered (using capacitors and possibly inductors (impulse noise canceling)) (this can be 2 banks of capacitors separated by a low value resistor (say 2.2Ohms) and connected to a bridge-rectifier.

Additional signal (power) condition is not needed (and or wanted). :)

This regulator has never shown any instability in any of the beta builds (and other).

See also http://www.diyaudio.com/forums/analogue-source/154210-mpp-438.html#post2861497
 
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Whoever wants a more precise RIAA here are my simulated values.
Precision is within 0.01dB (I will have to double check once I have the unit).

I happen to have two Teflon Custom values sample I got a long time ago with these exact values by Audience Aura-T :drink:


I have experimented with this values on another project and the difference with a normal Film cap is really drammatic.

I am wondering if anybody would be interested to order custom values of Cu-TFT by V-Cap.
They are so far the finest Teflon caps ever made.

Unfortunately for custom values we probably need 10-15 people because of the minimum quantity.
Obviously they are more expensive than a regular Film cap, but since this design is so good I feel it deserves the best parts.

I would like to get the feeling and see how many people would be interested in this.
 

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you are welcome.

The Teflon caps wouldn't be big at all.
Also, after I have tried the phono as is, if it sounds as good as I think, I will re-do the PCB to accomodate Texas Film Resistors eventual Teflon Cap 4 layer board probably.

Anyhow, the caps are pretty small, obviously a bit bigger than regular film, but still a very feasable size.

Still want to see how much interest as I would be pretty oriented in making a very cutting edge quality phono.