Mainstream Phono Stages Incorporating Premium Branded PCB Parts - Do They Exist?

But you don't know what capacitors were installed(?)  If you can say for certain that the amplifier sounds better, presumably after not having heard it for a few weeks while it was away for the upgrade, then the original capacitors might have been very low grade, because one's sonic memory is always to be mistrusted in it's capacity to perceive subtle differences over a time interval.  It would be fun to know what capacitors were in there, and what was used to replace them.

My Modwright has proprietary branded caps like Audio Note, from who I dunno.  The X upgrade in the PH9.0 in fact removes caps in the signal path.  I think it's not just about the caps but where they are in the signal path.

At this price point I would trust the makers to know what works and what doesn't.

Would I have gone into my Tavish Adagio and the Modwright to upgrade caps? Hell no!  I know of at least one maker who didn't believe more expensive caps made any significant difference.  As long as they were polypropylenes they were good to go.

While my experiments with caps have yielded some good results (EAR834 clone) I would rather depend on the circuit rather than the type of caps that are in there, especially a phono stage.

A fast look shows that Luxman used MCaps in the EQ500, but the basic caps, not any SGOs.  At least one other phono pre used proprietary branded caps but I don't remember who.

I think higher end caps just force makers to raise prices without any real advantages in sound quality.

My experiences of assessing Component Changes, ie, Cap' Resistor, Valve Bases used on a Phon' I own. 

Is that. Certain changes produced an end sound that had increased perceptions of Honesty, where the end sound produced was not what would be referred to as a ' betterment', but one that can be referred to as more believable. This type of assessment is very Subjective and will not find unaminous agreement, even though I have been a witness to some who have changed their thoughts about their initial assessment.

Where their decision has been to change parts We'd to at a earlier time. 

As said previously, a SS  Phon' I experienced from concept to production, become a Phon' that was making a very good impression. 

When this Phon' was experienced using Low Eddy RCA connections on both Cable and Chassis, along with PC Triple C Wire used from Cart' Pins through to Power Amp'. The experiencing this change to the Signal Path has been substantial for the better and very worthy of achieving in my home system. 

Atmasphere use teflon film and foil capacitors to couple one stage to another where it is necessary to block DC. Typically they use the VCap brand, which at least for the hobbyist like me are among the most expensive. And coupling capacitors are the most critical in the signal path. In general, teflon film and foil capacitors are most expensive, made by VCap (or whoever makes them for "VCap"), Solens, and RELcap, so far as I know. There’s also Mundorf film and foil using various kinds of foil. Metallized film capacitors can sometimes be excellent although few of them are high in cost. Dynamicap, Auricap,etc., are good brands. REL are always decent. I also like polystyrene film and foil capacitors but they seem to be nearly out of production in high voltage ratings. REL makes them too. You can get them with 100V ratings and maybe a bit higher for solid state applications. Texas Instruments "nude" bulk foil resistors (TX2575) are very transparent and cost about $12 and up, each. Dueland resistors are even much more expensive but so large as to be useful mostly in speaker crossovers. Also excellent and cheaper than TX are Caddock TF020, sold by M Percy, and tantalum resistors, probably in that order of excellence. You want the best possible resistor in phono loading and at the interface between stages. These are brands to look for in tube gear. In SS gear, which is nearly always on a PCB, you will find SMDs (Surface Mount Devices). These are tiny resistors/capacitors, and their use minimizes inductance in the circuit, because there is practically no space between them. I’m sure I am missing some pointers here. In my experience, using good parts, that may or may not be "expensive", is more important than, for example, tube rolling. For one thing, tubes age and change inevitably over time.  A good film cap is nearly forever, unless it sees a voltage much higher than its rating, which only happens if some other part goes bad.  Resistors are less profound, except as phono load resistance.

@ lewm

Thanks for the thoughts, but it seems odd to me that you would jump to such conclusions with so little information.

To address each point:

1st - Yes, I do know exactly which Caps were installed.

2nd - Yes, I do.  The difference in SQ created by the new caps is profound, not subtle. (strike two)

3rd - The original caps were the standard caps for this Ayre Acoustics V-5xe (~ $5K Stereophile "Class A') amp.  This preamp was, and still is, very well regarded.  The new, higher-line caps only made it better.  So, again, it is not clear why you would suggest that they 'might have been 'very low grade' (strike three).  

If you want a photo of the new caps, just send a PM.

Returning to @Wescoman's original question, my answer remains that the original manufacturer may be a great source for identifying higher-line parts (often from that manufacturer's higher product-line), and thus, maintain the intended SQ qualities. 

Furthermore, because these 'higher-line' were originally evaluated by the manufacturer, in their topologies, they may actually sound better than other, random premium-branded parts.

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