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Old 2nd February 2013, 12:02 PM   #2651
Salas is online now Salas  Greece
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Do any combination you may think of and decide subjectively. There are many stages in your system that comprise its final tone so I can just not say something solid from afar merely on intuition.
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Old 2nd February 2013, 02:54 PM   #2652
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OK

can you remember how much hrs burn In takes K75 ft-3 to sound optimal
I have heard that teflon need more time to burn In
have you used other russian PIO - MBGO - I use 10 uF MBGO2 for I/V Power Vref and think that It sound too forward
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Old 2nd February 2013, 03:51 PM   #2653
Salas is online now Salas  Greece
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I can't hear burn in for non electrolytics. Never could. Maybe you got a resonance with leads in the bypass. Using wires? Try 0.1-0.22R in series with the FT-3 bypass before one leg meeting the respective K75's leg.
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Old 3rd February 2013, 10:52 AM   #2654
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I continue to listen to K75 2.2 uF FT-3 0.1 uF - and wait the sound to become less rough
I am almost sure that Obbligato Premium Gold 4.7 uF Is rolled off at high and low end
and also It can not control bass but still It sound delicate and polite
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Old 5th February 2013, 10:27 AM   #2655
stajo is offline stajo  Sweden
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Hi

In the kit I got nicely matched quads of SK170. They are Idss 8,4 - 8,2 - 8,1. Last quadruple is 7,2 though and I wonder if you know it that can affect channel balance noticeable, since I'm building an 8 channel system.

Best
Staffan
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Old 5th February 2013, 12:01 PM   #2656
Salas is online now Salas  Greece
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It won't. Their transconductance is near enough.
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Old 6th February 2013, 08:56 AM   #2657
stajo is offline stajo  Sweden
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Quote:
Originally Posted by Salas View Post
It won't. Their transconductance is near enough.
Thanks Salas. I soldered them in yesterday along with some other stuff. When I came to the filtercaps I noticed that I had got 25 V filtercaps on the GB, which made me a little worried since there is going to be around 21ish VDC camelbacks straight into them.

So, as a big box of heatsinks also arrived yesterday, I came up with the idea of leaving the rectifiers out of the cards and make a centralized one, followed by a pre C-R (2 big caps and 8 separate 5-10 R resistors, one for each rail, sending fairly smoothed DC to the double 4700 uF caps as last separate C's.

What DC is to be aimed at over the last filterlyts (b4 the 10 R current setting resistor)?

Staffan

Last edited by stajo; 6th February 2013 at 08:59 AM.
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Old 6th February 2013, 12:14 PM   #2658
Salas is online now Salas  Greece
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10V more than Vout.
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Old 8th February 2013, 09:52 PM   #2659
stajo is offline stajo  Sweden
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Phew. Drilling and threading 32 M3s pulls me to the dark side. It took almost 3 sixpacks and in the end I was almost in to the ethyl alcohol. But now sits here 4 stuffed boards.
Click the image to open in full size.
I did some measures feeding them 1 by 1 by the trafo and two 5R6 ( closer to 5R5 actually) on the rectified plus and minus.
Click the image to open in full size.

Im gonna try make a chart. First column is card, 1, second card 2 etc:

Voltage drop 5R5:.....0,988/1,260.......0,910/1,183......0,979/1,194.....0,975/1,188

Makes current mA:....180/229.............165/215...........178/217..........177/216

Vout buffer (-/+):.....10,01/9,98........10,11/10,09........10,08/10,04...10,07/10,05

First is negative rail, second is positive on all above.

DC offset L/R mA:......0,3/1,1...............0,7/1,6............0,04/2,8.........1,5/2,2

So, positive takes more current then negative but outputs slightly less Vout.

What does the Jedi Council say. Am I still with the rebels or should I go talk to the man in the mask (I.e. do you think I should plug it in)?

Staffan
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Old 9th February 2013, 12:50 AM   #2660
Salas is online now Salas  Greece
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Jedi says the force is with you. The photon swords are functioning safely. Main CCS differences are due to PMOS/NMOS Vgs differences. Offsets are great. Due to big sinks are used you can experiment at a point to know if more hot rod rocks your planet better or not. 25% smaller setter for positive can give more balanced CCS with the benefit of hindsight if for newer current level test.

P.S. They give more for 5R6 usually. Maybe the VA is low and the input DC dropped?
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