KGSSHV Carbon Build Thread

[JoaMat]

Nice build indeed. Really like the look of the power switch, espacailly with darker background.

Glad you are going for KGBH.

Now 20% off.  Join the RASS movement.

[nopants]

if you need 1968s for the kgbh I have quite a few that I don't think I'll end up using , as well as populated boards

[headinclouds]

32 minutes ago, nopants said:

if you need 1968s for the kgbh I have quite a few that I don't think I'll end up using , as well as populated boards

Thanks but I do have all the components for the KGBH.  I have suspended building for what passes for summer over here.

[headinclouds]

6 hours ago, wink said:

Wonderful craftsmanship.   

 

Only one problem, though    

 

There's only one (1) Stax output socket      

Wink,

I love your use of emoticons.

You got me thinking about driving two Stax.

I briefly thought of putting two sockets in but quickly decided not to.

·         I don’t want it

·         No-one asked for it

·         It spoils the symmetry

·         Why would you drive two Stax at same time unless for “comparisons”, assuming your partner does not want to sit listening to the same stuff as you.

I know the Carbon has plenty of current but won’t the sound be compromised by more than doubling the 120pF with two in parallel? 

[spritzer]

It can easily drive two sets at the same time but I agree, two output sockets are just a waste of everything. 

[nopants]

haha of course the guy who's got one amplifier for every headphone can say that

something tells me that ratio is slightly off but I'll stick with it

[johnwmclean]

Just for you Erwin (wink).... my next Carbon front panel.

Twos good too 

x 2

Edited July 28, 2016 by johnwmclean

[GeorgeP]

1 hour ago, spritzer said:

It can easily drive two sets at the same time but I agree, two output sockets are just a waste of everything. 

Yeah, always wondered why two sockets is the Stax norm. Other than comparing two 007s at the same time once, I think think of a single other time where I needed two jack. Dual bias, sure.

[gepardcv]

1 hour ago, GeorgeP said:

I can't think of a single other time where I needed two jack.

Who said anything about need? 

[Dave R]

The good thing ( IMO ) about having two Stax sockets like on the BHSE and the one John's recently posted, is if two wanted to listen at the same time it can obviously be done, however I have tried this with a 009 and 007, and both produced different volumes with the 009 sounding much louder.

[wink]

2 hours ago, johnwmclean said:

Just for you Erwin (wink).... my next Carbon front panel.

Twos good too 

x 2

     one for each socket.....

I can't count the times I've had someone over to hear some tracks.

With 2 sockets, I just break out my 2 SR-007's &/or SR-009's and we compare notes on what we heard - zimple......

 

The more I look at that pic, the more I seem to want one.......  

[astrostar59]

I wonder if the sales logic (not technical logic) of 2 sockets was the 'wife' factor? It can be a reclusive hobby with one headphone I guess. But in my environment especially in the evenings headphones really works for me.

[purk]

Grate stuff John!

[s_r]

Pretty fantastic build headinclouds

As for my PSU issue, I've now replaced the STN9360, the 10M90S & DN2540 beside each other and the cree so far. Still no change in behavior though. If it's any clue then pin 1 of the 10M90S closer to the cree reads +10V, pin 2 & pin 3 are +13V (referenced to ground).

[JoaMat]

Well, I’m running out of ammunition. Blind shot, could it be the 12V Zener that’s the problem?

One way to proceed is George’s advice.

On ‎2016‎-‎07‎-‎27 at 2:52 PM, GeorgeP said:

Diode test? Or, what I have done may times to find issues or faulty parts, is measure resistance at various parts of the circuit between the good and bad boards - not the most accurate and sometimes the values fluctuate at certain parts of the circuit, but differences here can point to the culprit fairly quickly.

Also want to quote Kerry, from The ultimate DIY? A Stax SRM-T2!

On ‎2012‎-‎02‎-‎15 at 6:45 AM, Kerry said:

Another thing you can try is to use a diode tester against all the combinations of the three pins per device. Check from the good channel to the bad channel. You will likely see differences (shorts, leakage or non-conductive issues) on the bad channel. If anything looks different between the good and bad channels, then replace that device in the bad channel.

[MLA]

2 hours ago, s_r said:

Pretty fantastic build headinclouds

As for my PSU issue, I've now replaced the STN9360, the 10M90S & DN2540 beside each other and the cree so far. Still no change in behavior though. If it's any clue then pin 1 of the 10M90S closer to the cree reads +10V, pin 2 & pin 3 are +13V (referenced to ground).

Extreme long shot; I went through the same part by part routine with one of my PSU boards where the regulation did not kick in, and in the end it turned out to be the KSC5026M:s. I had to replace both at the same time to make it work. Perhaps diode test those first?

[spritzer]

23 hours ago, nopants said:

haha of course the guy who's got one amplifier for every headphone can say that

something tells me that ratio is slightly off but I'll stick with it

I think the ratio is pretty much spot on...    Given the number of headphones...yeah that is a lot of amps... 

[sorenb]

 

1 hour ago, MLA said:

Extreme long shot; I went through the same part by part routine with one of my PSU boards where the regulation did not kick in, and in the end it turned out to be the KSC5026M:s. I had to replace both at the same time to make it work. Perhaps diode test those first?

did you test the KSC5026 out of circuit?

[MLA]

It's been a few months since so I don't remember with certainty. I think I did, but only after replacing a bunch of other parts first (cree, 10m90s, stn9360...), so something else might well have killed them. Once I got it working, I was too happy to figure out the details of the problem

[Dave R]

On 28 July 2016 at 5:30 PM, wink said:

     one for each socket.....

I can't count the times I've had someone over to hear some tracks.

With 2 sockets, I just break out my 2 SR-007's &/or SR-009's and we compare notes on what we heard - zimple......

 

Exactly my thought, however as Geoff mentioned about his version of the Carbon, having two Stax sockets would spoil the symmetry of that amp, whereas the way John's designed his Carbon having two sockets adds to the aesthetic's, ( IMO ).

[purk]

My Carbon has three jacks:  2 Stax Pro & 1 HE90.

[Dave R]

1 hour ago, purk said:

My Carbon has three jacks:  2 Stax Pro & 1 HE90.

Have you posted a photo purk ?

[purk]

Posted this picture awhile back...sorry for not having a better picture.

Edited July 29, 2016 by purk

[s_r]

PSU issue solved I replaced one of the KSC5026Ms and now the supply outputs +452V. Probably replaced more sand than necessary, but I'm just glad it works now.

[astrostar59]

2 hours ago, s_r said:

PSU issue solved I replaced one of the KSC5026Ms and now the supply outputs +452V. Probably replaced more sand than necessary, but I'm just glad it works now.

Wonder how that parts failed?