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FS: Dynaco PAS with full Curcio mods

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Actually, with all the mods (line stage, phono stage & regulated power supply) this isn't a PAS at all anymore - it's more a pared-down version of Joe Curcio's "Daniel" preamp. But I digress...

Read all about each of the three main components here:
http://www.dynaco-doctor.com/pasdes_3.htm

This is a very quiet preamp - hiss and hum are inaudible more than a foot from my Fostex 206s. It also pretty much stays out of the way, in the sense that it won't help a poor sounding amp nor muddy up a good one. I found that it sounded much better (and quieter, for some reason) driving my 45 SET amp than the ST-70 it was originally built (and designed) to sit in front of.

Included are a pair of Amperex PQ 6922s (USA, white label, gold pins) and a single Tungsram 12AT7.

Full documentation for the mods will be provided.

I'll also throw in the original Dynaco PAS boards. They should work as is, but they've been modified a bit from the original.

I'm selling because I no longer need the phono stage, not to mention that my wife says I have too much gear lying around. The scary thing is that I'm starting to notice it too...

Roughly $500 invested - asking $300 + s/h.

Additional pics available upon request. There is a cover; it's just not as interesting with it on.
 

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Both are there according to either the original or Joe Curcio's design; aside from sourcing my own parts, I didn't stray from Mr. Curcio's instructions. These days I'm scratch building... :smash:

The 10 ohm resistor between the negative terminals of the input & output is intended to foil potential ground loops.

The 510K across the input, when considered along with the rest of the PAS circuit, is there to accommodate the 470K input impedance of the ST-70. In any case, I most likely replaced the originals while the stock boards were still in since, according to Mr. Curcio, they're not necessary with the upgrade boards (but, given the low output impedance of Joe's design, don't hurt anything if left in either).
 
Thanks for the explanation. Scratch building has to be a more gratifying process let alone the end result being more of a product of labor of love. Not to mention the zen-like exercise of patience and contentment, which however with perseverance, evolves to a skill over time. Not worrying about the projects amassed but seeing, embracing, and honoring the fulfillment of whatever, however small, that can be done now. The secret lies in doing. Motivation should never flee if one could do one thing at the time almost with a blind eye turned on all else. Forgive me the tangent. Peace and all the best.
 
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