KGSSHV Carbon Build Thread

[kingofsnake]

Congrats....joehpj.

  Thats a nice looking build you have there. Did you drill the Stax socket hole yourself? if so you've made a really neat job of it. Is this the pot that you have used? worth the money?

http://www.ebay.co.uk/sch/i.html?_from=R40&_trksid=p2050601.m570.l1313.TR0.TRC0.H0.TRS0&_nkw=121828993126&_sacat=0

 

[joehpj]

Sorry, the link was wrong. It shows 0 items

Taobao seller drilled the hole for me. 

It's a Chinese sealed 23 stepped VR. Overall quality was good, no issue with sound. This is the second one I brought, but the rotation is tighter this time. Recommended.

https://item.taobao.com/item.htm?spm=a312a.7700824.w4002-1004073654.21.nkSptS&id=522043952195

Edited April 26, 2016 by joehpj

[headinclouds]

Nice build Joe! 

[johnwmclean]

Very nice. May I ask your current and temps?

[chinsettawong]

Very nice!

[joehpj]

current is 20mA

Temp is lower than I expected. Room temp is about 25-27 and I can put my hand on the sink by just feeling a little bit hot after 2 turning on for 3 hours. I think the huge sink did a good job. size:12.5*31*5cm, the base is 1cm thick. And I lift the whole chassis up by using high screw-type feet. (4cm)

Edited April 26, 2016 by joehpj

[purk]

What do you think of the amp..sound wise?

[HemiSam]

Great looking build, Joe.  I like the dimensions of the amp...the footprint is convenient.

HS

[GeorgeP]

8 minutes ago, joehpj said:

current is 20mA

Temp is lower than I expected. Room temp is about 25-27 and I can put my hand on the sink by just feeling a little bit hot after 2 turning on for 3 hours. I think the huge sink did good job. size:12.5*31*5cm, the base is 1cm thick.

What voltage psu have you built? Looks to be 400v or is it less?

[joehpj]

I still need some more days for detailed description. I've only build a KGST and this is the second one. Never heard a SS/SShv, so neither can I compare with . Sound wise both sounds pretty alike. Carbon is more dynamic and.......brutal. Bass is better than ST. It's puncher and tighter. I think it benefits from the new CCS. My ST build only has single 10M90S. But ST has warmer mid range makes it better for presenting vocal recordings. (2nd distortion?) Carbon is more sensitive to front end and has lower tolerance to bad recordings. Bad recordings played with carbon were harsh.  Maybe it's due to the lower distortion and higher output. My HP is modded 007A mk2.9. A friend of mine build SShv/ST/Carbon told me Carbon has best overall performance. 

400V@20mA. Measured about +-402V after warmed up. The pass transistors of GRHV are not hot. So the amps can use a large portion of the sink. All pass transistors including LV are off board, so there's no sink in the case and makes the temp in the case lower. And also the junctions of the case are tight so every plate of the case works as sink,too.

Edited April 26, 2016 by joehpj
misspelled

[jose]

For LV is correct a sec. With 18-0-18 vct @ 600mA ?

[sorenb]

3 hours ago, jose said:

For LV is correct a sec. With 18-0-18 vct @ 600mA ?

would be fine

[jose]

Thanks Sorenb!!

I just ordered this.

 

[eggil]

nice amp joehpj!

[jose]

Is safe use a metal screw for attach 10m90s to to the heatsink?

I bought the poly sulfide shouder washer but I´m not sure if this is enough

[spritzer]

I've had two arc through so I'd advice against it. 

[JoaMat]

If you use the correct shoulder washer and don't smear the junction with conductive thermal grease than it's safe to use steel screw.

[gepardcv]

What about the SiC devices? Any special considerations for those, or just mount with a metal screw? (The tabs look insulated, so it doesn't seem like they need PEEK, anything exotic, or unusual washers...)

[JoaMat]

Looks insulated but bottom is not. I use aluminum oxide insulating washer and steel screw. Avoid conductive thermal grease.

[spritzer]

16 minutes ago, JoaMat said:

If you use the correct shoulder washer and don't smear the junction with conductive thermal grease than it's safe to use steel screw.

My two failed units would beg to differ.  I've stopped using the shoulder washers as they simply don't cut it. 

[jose]

Thanks for the replies.

I used nylon screw and aluminum oxide Insulator on my KGST whithout problem.  Yes, you haven´t a large press but it´s safe.

Well, now I have the Aavid poly sulfide shouder washer too:

http://www.mouser.es/ProductDetail/Aavid-Thermalloy/7721-10PPSG/?qs=%2fha2pyFaduh6C0mWin5INmhh82HyIUQkqhWvlgOyq9gqLaH17qc%2f0A%3d%3d 

But I´m not sure.

 

[astrostar59]

On 26 Apr 2016 at 5:17 PM, joehpj said:

400V@20mA. Measured about +-402V after warmed up. The pass transistors of GRHV are not hot. So the amps can use a large portion of the sink. All pass transistors including LV are off board, so there's no sink in the case and makes the temp in the case lower. And also the junctions of the case are tight so every plate of the case works as sink,too.

I read it may sound less forward / harsh if you drop the mA to 17?

[gepardcv]

1 hour ago, JoaMat said:

Looks insulated but bottom is not. I use aluminum oxide insulating washer and steel screw. Avoid conductive thermal grease.

What is the part number for the aluminum oxide insulating washer you use?

[spritzer]

59 minutes ago, astrostar59 said:

I read it may sound less forward / harsh if you drop the mA to 17?

Where did you read such bullshit? 

[JoaMat]

21 minutes ago, gepardcv said:

What is the part number for the aluminum oxide insulating washer you use?

4180G