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Old 8th March 2010, 09:08 PM   #1071
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I have been listening to it for a while, some differents cds of various artists.I'm not very good at critical listening, but I will try to describe what I hear.

Music seems to be more holographic, the spacial sense of the instruments get improved. I play bass too, and I can hear more defined notes, like if the string were there, vibrating in front of you head
In the strings from the guitar happens the same, they apear all around you.
It is very fast too, I have lot of recordings with fast played instruments, and hearing them you can realize every stop, every note after the other. Fast played drums are very defined, every one is in his place and sounding only when they should.

I hope this amateur opinion will encourage you to try this mod. You only need to source some tiny heatsinks and a pair of resistors. And, if you don't notice anything or like it anymore, just swap the older ones in a minute.

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Old 9th March 2010, 01:11 AM   #1072
Salas is offline Salas  Greece
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is good for the glowing shunties. As for the polar bear...
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Old 9th March 2010, 01:43 AM   #1073
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Gordon Holt offered a number of great observations, one of them
being (paraphrased) "You can hear everything that is done to
the signal"

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Old 9th March 2010, 10:42 AM   #1074
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So I spent more time last night listening to the capacitor mod (see here: cap mod suggestion by salas

The change for me is fairly subtle, but as it seems that voices in particular have changed. I also think it sounds ever so slightly cleaner - kind of the way the very best valve amps do. The other change - the voices bit - it seems that voices stand out and seem more real, better rounded in space. On a few different tracks I tried I got this same result.

Is this what you have observed Salas?


I now have a major itch - what will it sound like if I used 0.33uF instead of 4.7uF......

Fran
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Old 9th March 2010, 02:52 PM   #1075
Salas is offline Salas  Greece
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Compatible subjective observations. Now that you surely got the ''best cap there'' itch, snip those legs a bit above pcb so you can exchange some without pads lifting sooner or later.
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Old 9th March 2010, 03:43 PM   #1076
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After being on all the night, I have noticed in the morning that the heatsinks, specially the smaller ones, are hotter than yesterday. Maybe only because of higher ambient temp. But the fact is that i am feeling concerned about them, now I can't hold my finger for more than 5 secs. Do you think is something to worry about?

Maybe I will try to snap in series another small resistor to lower it a bit. Is really important to hold the CCS between 200 and 250mA to achieve the best performance? Or maybe is more or less the same than, let's say, between 100 and 150mA?


BTW, after a long night listening session, I mantain my first opinion. It sounds stunninly clear and defined, clearly better than before.
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Old 9th March 2010, 03:52 PM   #1077
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Try 15R 5W. In the phono I routinely run them form 150-220mA and they are fairly close. Here you have the benefit that more is left to the Mosfets, due to less audio part consumption. It may lose some bit of sonic or not but judge for yourself.
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Old 9th March 2010, 03:57 PM   #1078
Salas is offline Salas  Greece
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Quote:
Originally Posted by Nelson Pass View Post
Gordon Holt offered a number of great observations, one of them
being (paraphrased) "You can hear everything that is done to
the signal"

Is he still alive? A most succinct man.
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Old 9th March 2010, 06:40 PM   #1079
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I forgot to say that, despite the extremely low offsets of -0.82mv and -1.54mv in the output of the DCB1, it's only caused by termal drift.
I saw that by blowing a bit over the board. You can see falling down the numbers in the DVM until 0, and then it increases in the opposite polarity.

So you made a PERFECT circuit guys, in depends ONLY of the components drift. The circuit can't be bettered itself.
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Old 9th March 2010, 09:01 PM   #1080
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Just for information to some of you guys, I bought 100 led to match them for the Shunt Reg and out of the 100, this is what I got:

Led YEL, Mouser 593-VAOL-3HCE4
Tested using 9V supply, 1K resistor
DVM FLuke 87, 4-1/2 digits meter

Led-Vf QTY
1.91V = 5
1.92V = 1
1.93V = 32
1.94V = 53 (Most 1.936-1.937V)
1.95V = 8
1.96V = 2
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