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Lol, the last time my offset went to shx was when it costed me 10m90s and couple Resistors.  
Yes, it is 2U.  I am using Thermal paste from Artic silver but went with Ceramic compound type.  Now I have my thermal gun, the Carbon hottest part of the heat sink read 42 C each side, a bit different.  The Cree 100007 on the HV reads 41 C, and on the Amp board reads 42.5 C after couple hours on.
 
i love that bottle!


Can you place the gun physically touching the screw on the Cree device and read the temperature?
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My own Carbon, not going anywhere... IMG_6585 IMG_6590 IMG_6592 IMG_6593 IMG_6595 IMG_6596 IMG_6597

So I finished my my KGSSHV Carbon a few weeks ago. Been too busy listening to it, but I thought I would share my effort and measurements. I am lucky enough to have access to some test gear that allowe

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1 hour ago, Pars said:

Same here. Single sided sandwiched with double sided blanks? I'll give you an A for creativity! I personally will stop at 2-layer, and commercial houses are so cheap anymore I don't bother with those :rolleyes:

 

Yes, single plus double. I’ve a CNC machine. Drilling the board is easy, fast and precise. Milling. Boards are done in a couple of hours. Making the vias  and building the two boards together went very smooth. My first attempt - maybe beginners luck.

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7 minutes ago, luvdunhill said:

 


Can you place the gun physically touching the screw on the Cree device and read the temperature?

 

It is infrared gun with distance within 2 laser points.  I directly spotted on the Cree and it read 42 C even after 6 hours.  One of the Cree does read 46C but it is on the GRHV

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It's just that those IR guns aren't that accurate even from a few inches away. They average the radius and that can skew the numbers. Anyways, I think something is amiss - but if you have checked it out, then just enjoy the sweet sweet music.

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25 minutes ago, nopants said:

are you using the same case you were using for the grounded grid dht and so forth? looks familiar, not that i'm complaining

All may cases look the same. The grounded grid is still untouched. This one has been serving as KGSShv and Blue Hawaii. Have an agreement. - number of working amplifier should be constant. New amp demands a sacrifice.

My closet.
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T2 is my preferred amplifier. The rest come and go.

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5 hours ago, JoaMat said:

 Have an agreement. - number of working amplifier should be constant. New amp demands a sacrifice.

If ever an agreement needed to be revised, or preferably, discarded, this is it........:ph34r:

Some sacrifices are just not psychologically viable........     B)

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9 hours ago, GeorgeP said:
9 hours ago, JoaMat said:

...

T2 is my preferred amplifier. The rest come and go.

Amen.

I wrote that?:huh: wow!

 

7 hours ago, chinsettawong said:

Hi JoaMat,

I think you should try to make your own headphones.  It'll be a lot of fun. :)

I’ve been looking through the window into your wonderful world of DIY headphones for years. Thanks for inviting me.:)

 

4 hours ago, wink said:

If ever an agreement needed to be revised, or preferably, discarded, this is it........:ph34r:

Some sacrifices are just not psychologically viable........     B)

The number is set due to necessity. Imagine our small living room and 29 full sized electrostatic amplifiers with associated power supplies. Practical impossible. As long as Kevin, Kerry and others are constantly providing us with new projects the space of our apartment is my bottleneck.:(

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1 hour ago, JoaMat said:

I wrote that?:huh: wow!

 

I’ve been looking through the window into your wonderful world of DIY headphones for years. Thanks for inviting me.:)

 

The number is set due to necessity. Imagine our small living room and 29 full sized electrostatic amplifiers with associated power supplies. Practical impossible. As long as Kevin, Kerry and others are constantly providing us with new projects the space of our apartment is my bottleneck.:(

I don't see the problem........      :P

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Now, just for some curiosity.  I measured my Carbon again.  One of my board with Opto Servo engaged always keep 100-300 mV from start up to lowest of 40-50mV.  One other board does -1.5V and hanging around -0.5-0.6V.  Questions are

1/ is it ok for each of the board to be this much different ?

2/ what is really the allowable tolerances for this offset voltage threshold ?

thank you so much for your time

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I’ve one grounded grid and the three layer Carbon (one channel only), all boards with opto servo and no trimmers with associated resistors. All of them are within 50 mV. If unbalance then the average is within same mV range.

Your first board seems to behave as mine. For the other – are you sure the trimmer not is set at a (slightly) to low value? The trimmer must be set to an offset above zero volt without the servo engaged. Turn the trimmer and see what happens….  you have probably already done that?

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20 minutes ago, JoaMat said:

I’ve one grounded grid and the three layer Carbon (one channel only), all boards with opto servo and no trimmers with associated resistors. All of them are within 50 mV. If unbalance then the average is within same mV range.

Your first board seems to behave as mine. For the other – are you sure the trimmer not is set at a (slightly) to low value? The trimmer must be set to an offset above zero volt without the servo engaged. Turn the trimmer and see what happens….  you have probably already done that?

Yes, I have already measured all values to be equally across both boards on balance, offset, current adjust.  However, when I put in the Servo, one of my board has that huge voltage gap ? I also replaced the Op27.  I hear for Opto Servo we need more than 10V , so my offset is now at 18-18.3V after 20 minutes

Edited by Whitigir
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17 hours ago, JoaMat said:

T2 is my preferred amplifier. The rest come and go.

Amen to that too.

I sometimes use another system, but no one beats the hell out of the headphones like the T2.

Both Dr Hayashi & Gilmore deserve a thought each time the music starts.

PS : my Grounded Grid is coming, gonna be the "portable" little brother...

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3 hours ago, Whitigir said:

Now, just for some curiosity.  I measured my Carbon again.  One of my board with Opto Servo engaged always keep 100-300 mV from start up to lowest of 40-50mV.  One other board does -1.5V and hanging around -0.5-0.6V.  Questions are

1/ is it ok for each of the board to be this much different ?

2/ what is really the allowable tolerances for this offset voltage threshold ?

thank you so much for your time

measure leg2 and leg6 of the OP27 against ground, might give you a clue to what is going on ...

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21 minutes ago, sorenb said:

measure leg2 and leg6 of the OP27 against ground, might give you a clue to what is going on ...

Leg 2 is 0V and leg 6 is -1 V on both.  I replaced the dn2540 and it is still similar.  It starts around -1.5 or -1.6V and hang around -0.4 to -0.6.  After 10 minutes with Servo dropped in, both board is hanging around -100 to - 200mv the problem board now hang -350mV to -650mv after the replacement of dn2540

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2 minutes ago, Whitigir said:

Leg 2 is 0V and leg 6 is -1 V on both.  I replaced the dn2540 and it is still similar.  It starts around -1.5 or -1.6V and hang around -0.4 to -0.6

you say you have around -1.5V on the output? and have 0V at leg2 (like in 0.000V?), and -1V at leg6 ? 

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3 minutes ago, Whitigir said:

I just replaced that Op27 too, and together with DN2540.  What else could be problematic ?

and you didn't by any chance enable servo1 as well?
what do you have at leg4, leg7 and leg3 of the OP27?

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This seems interesting.

Do you dare to remove the 120 ohms - or whatever you have there - which is in series with the trimmer and see what happens? Than offset is set by pzta06 entirely.  That's the way my grounded grid and Carbon work. Haven't had any smoke so far.:rolleyes: Knock on wood.

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