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Old 6th May 2009, 05:10 PM   #721
Dansk is offline Dansk  Denmark
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Default Wow!

Quote:
Originally posted by Babowana



I believe that the voltage gain will be reduced.
R of 475 ohms is there to prevent potential oscillation . . . I think.
220V might be okay . . . tho . . .



Now, that's what I call voltage gain!

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Old 6th May 2009, 09:50 PM   #722
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oops . . .

Why "V" is there . . . ?
"V" is not even a neighbour of "R" living on my keyboard . . .

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Old 8th May 2009, 08:42 AM   #723
Dansk is offline Dansk  Denmark
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-Well, I think you're understood anyway...
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Old 8th May 2009, 09:43 AM   #724
Tolu is offline Tolu  Germany
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220V would be nice gear for Pink Floyd world tour
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Old 8th May 2009, 10:50 AM   #725
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Hey Tolu,
On the left is your single FET solution given the 2,2V offset DAC, your 7kohm Lightspeed and 24V DC.
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Old 15th May 2009, 10:04 AM   #726
Telstar is offline Telstar  Italy
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I'm thinking to use the JBOZ with my F3. Any recommendation of values? i'm trying to guess the "sweet spot" on paper
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"The total harmonic distortion is not a measure of the degree of distastefulness to the listener and it is recommended that its use should be discontinued." D. Masa, 1938
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Old 16th May 2009, 02:27 PM   #727
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The sweet spot must be found with actual parts and measurements.
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Old 16th May 2009, 09:44 PM   #728
hihopes is offline hihopes  South Africa
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Try using a trimpot as the drain load. Adjust for approx half B+ on drain and fiddle from there - oh, and don't skimp on the power supply. You can hear every single little improvement in it. Mine is MEGA!
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Old 16th May 2009, 10:05 PM   #729
Telstar is offline Telstar  Italy
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Quote:
Originally posted by hihopes
Try using a trimpot as the drain load. Adjust for approx half B+ on drain and fiddle from there - oh, and don't skimp on the power supply. You can hear every single little improvement in it. Mine is MEGA!
I'm thinking of using the Shiny psu, very oversized or a 15V battery.
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Old 17th May 2009, 08:27 PM   #730
hihopes is offline hihopes  South Africa
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I started with 2 x 9v batteries and a charging circuit, but it was more trouble than it was worth. Sound was good but unremarkable. Then I tried Shiny and after ironing out an oscillation problem, it was quite nice. Since then I have almost lost track of all the improvements added, but I can report that each was audible. I have LOTS of BIG caps (CRCRCRC); a choke; an LM317 (with black Gate caps); a "Pink Fish" gyrator; the Shiny reg; some more caps, including paper in oil. I have also made some mods to the basic JBOZ with a CCS on the source, another 2sk147 on the drain and adjustable NFB. I don't think I can do much more to imp[rove on it. It is very clear and quite dynamic, (though not "knock your socks off"). It does sound like solid state, though not in an objectionable way. I am now heading into tube territory for a comparison.
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