On the subject of internal wiring of a preamp, I have made just about every combination over the decades. Normally, a single motherboard with various in and out wires to the outside. For a time, I tried to incorporate much of the external wiring (to the connectors for example) by extending the motherboard right to the connectors in order to improve the thru-path. The JC-80 was like this. What I found is that butting up the board to the connectors could be problematic when it came to vibration or stresses on the motherboard. I prefer, today, a main board or two, with wire connections to the outside.
Now, the CTC Blowtorch is an extreme example of what most of you should NOT do. In this case, every gain block was separate from each other and we allowed a great deal of extra space INSIDE the case for added components. This was decided from the beginning, as we were prepared to customize each preamp for its individual customer. For example, while our inputs were normally single ended (I still prefer it today) some people wanted balanced inputs, some wanted a Vendetta phono stage, yet other people might want an additional output current buffer to drive extra long lines (nobody ever asked for this, but we made the space available). This made for a fairly large case, and therefore fairly long wires to interconnect everything. Thank goodness, Bob Crump, the major builder, had found a really good sounding silver wire, (not electrically shielded) that he could use to attach everything. We were very touchy about connecting wires and only this expensive, and thankfully attractive single connecting wire made the grade. We had use a lot of this wire and also separate each wire from the others, because we had no added shielding. However, inside the thick case, the outside world did not have much effect. The silver wire that we used is not available anymore, so far as I know. Too bad, but is was certainly better than a lot of extra 'marginal' circuit board material like the JC-80 used.
Now, the CTC Blowtorch is an extreme example of what most of you should NOT do. In this case, every gain block was separate from each other and we allowed a great deal of extra space INSIDE the case for added components. This was decided from the beginning, as we were prepared to customize each preamp for its individual customer. For example, while our inputs were normally single ended (I still prefer it today) some people wanted balanced inputs, some wanted a Vendetta phono stage, yet other people might want an additional output current buffer to drive extra long lines (nobody ever asked for this, but we made the space available). This made for a fairly large case, and therefore fairly long wires to interconnect everything. Thank goodness, Bob Crump, the major builder, had found a really good sounding silver wire, (not electrically shielded) that he could use to attach everything. We were very touchy about connecting wires and only this expensive, and thankfully attractive single connecting wire made the grade. We had use a lot of this wire and also separate each wire from the others, because we had no added shielding. However, inside the thick case, the outside world did not have much effect. The silver wire that we used is not available anymore, so far as I know. Too bad, but is was certainly better than a lot of extra 'marginal' circuit board material like the JC-80 used.
There is that saying: "Never change the winning team".
I also have been using Multicore 62/36/2 since at least the late 80's and have tried other manufacturers as well. I know, it's very subjective, but no other manufacturer was able to beat Multicore for the "feel" of "flow" in my case. Now I'm well stocked with Multicore - I have at least several kg.
Dan,
I suppose it would prudent to understand why the little ferrites are there before removing them and replacing with twisted wire and if that would cause detrimental effects somewhere else.
JC......anyone?
And would something like the quad eutectic be easier for a beginner, because research points to 99.3/.7 being a pita to use?
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Thank you for searching the old posts on AD797, indra1. I have read them, earlier. Also thanks for JC comments. However, I was rather interested in more detailed description of sound of the chip, as it can be done, IME. This is also related to another thread and I will bring my long term impressions quite soon, in two weeks latest.
It is fine and more than adequate to the rest of the circuit. I would keep it as it is. The only objection - 100k is quite high re noise. However, without detailed knowledge of the circuit diagram I would keep it.
Oops, Alps indeed.
I was talking about the amp that PMA posted the picture of.
https://www.parasound.com/product-images/hint6_black_inside.jpg
I didn't see any Alps there. And yes, that BB part is what I had in mind. I should have said 'digitally controlled volume control' instead of 'digital volume control'. Anyway, in my book that part is a no-no.
+1
I like a bit of luxury, so the original Sn62/Pb36/Ag02 is my first choice; alternatively the AIM at Mouser. They both ship to private persons. The Cardas should be close, with some extra copper (Cu) thrown in, for about twice the price.
But it’s five 9 copper! 
Elektroj......this is the one in question, the original Hint; they are very close.https://parasound.com/product-images/hint_black_inside.jpg
Edit.....huh, just noticed parasound stock pic volume doesn’t exactly represent what I have?
Elektroj......this is the one in question, the original Hint; they are very close.https://parasound.com/product-images/hint_black_inside.jpg
Edit.....huh, just noticed parasound stock pic volume doesn’t exactly represent what I have?
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I like the AIM with Silver and use it for prototypes. The lead free is for production.
If my memory serves me correctly, John Siau (Benchmark) indicated the ESS 'hump' distortion was mostly attributed to CM distortion and careful matching of the post I-V phase summing stage was the solution.
I did advise quite some time ago to look into achieving very high CMRR on the final phase summing stage on the 9038 sabre DAC thread when it was
stated that Sabre has zero rejection of noise on AVCC. Of course this is not the case at all and any noise or distortion on AVCC will be rejected in the
post I-V phase summing stage ** depending on how high that stages CMRR
is.
T
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