[stringgz301]

Thanks Sachu.  Well it's definitely related to the input wiring, because when I disconnect the input and input ground from each board the amp is dead quiet.

 

[funch]

 
Quote:

I also used the Glassjar kit and experienced same problem with both boards.  I replaced both regs and all is fine now.  Perhaps bad batch of ld1085's.
 


 

Thanks for the input. I'll try new reg's.
 
Update:    Yep, that was it! New reg's and all is well. I wonder if Jeff did in fact get a bad batch of reg's?

 

[johnwmclean]

To clarify,
 
Grounds are: 2 inputs, 4 amp boards, 2 speaker posts. The gound that you labelled “from input grounds” is actually the chassis ground connection.
Quote:

Grounding: right now, each board has 3 sg grounds (I'm using the alternate wiring scheme connection at the front of the board), that all connect to a central terminal.  That ground is isolated from the case (should it be?).  The IEC ground is connected to the case.  
 
A bit of question mark for me is the Khozmo attenuator (4 channel).  It has 4 inputs plus a ground connector, and 1 pair per channel of output and ground connections.  I currently have it wired like the attached (Pic from john mcclean, my annotations, using wire leads instead of his diy bridge between ground connections).  Not sure why he has 2 leads connected to each output ground connection.  Also, not sure why the bridge is required given that on each board the IG connects through the ground plane to SG.
 
 
Any and all help is much appreciated.

 

 

[stringgz301]

Thanks John. So where did you connect the 2 input grounds? Also, my khozmo came with a wire bridge soldered between the middle and upper position for each output and ground position. Was yours different?

 

[johnwmclean]

[size=medium][size=13.0px]Yeah I’ve seen different variations.

Apologises I’ve confused myself, scrap what I mentioned earlier as this was the attenuator for my Beta22 not my EHHA.

Here’s an installation guide for unbalanced,
http://www.partsconnexion.com/prod_pdf/Khozmo_install.pdf

The two input grounds can be connected to any of the ground pads, they should all be electrically shorted once you connect everything up, to ensure this I installed pins into each ground pad and with wire jumper, not conventional, and not really needed, but it worked for me, the amps as quiet as a mouse.

Looking at the EHHA balanced wiring diagram Pin 1 is not part of the star ground, so wire accordingly.[/size][/size]

 

[Jrossel]

Quote:

 

Thanks for the input. I'll try new reg's.
 
Update:    Yep, that was it! New reg's and all is well. I wonder if Jeff did in fact get a bad batch of reg's?

Hi funch.  Sorry about the regulators.  Turns out I have a batch of fixed regulators by mistake.  Let me send you a refund for the cost.  Now I need to contact several other kit builders too, hopefully they are not pulling out too much hair in frustration.
 
Jeff
 

 

[funch]

Here's mine.
 

 
Nothing special. Kit from Glassjar. Par-Metal case with their 3/16ths thick faceplate.

 

[sachu]

simple and clean funch..this is your second EHHA eh..nice!

 

[WyldRage]

Hum... Seems I never posted mine, so here it is:
 

 

[jdkJake]

Nice build Funch, love the literal star ground, nice touch. What are you using as a power on circuit? That board looks interesting. Does it stage the power on (heaters followed by rails)? Is it multi-positional?

 

[jdkJake]

Nice build WyldRage. Did you put any panes in your "windows" or are they just open?

 

[WyldRage]

They have panes. I used front panel express for the EHHA's front panel. The original panel, which you can see on the first picture, did not have panes nor inscriptions. I drilled it myself, and the results were rather disappointing.

 

[funch]

 
Quote:

Nice build Funch, love the literal star ground, nice touch. What are you using as a power on circuit? That board looks interesting. Does it stage the power on (heaters followed by rails)? Is it multi-positional?

 
 Hey, Jake! Thanks. It's this:http://glass-ware.stores.yahoo.net/acswitch.html. Three position. I used one on my first EHHA build, and have installed one
in my Bijou. Very nice switch. Quarter-inch shaft, BTW.

 

[audionut]

Gentlemen, Looks like the 1N5313 for CRD1 is no longer available through Mouser. The Mouser tech said the 1N5314 would probably work, but I wanted to see what you guys say and how critical that part is. The data sheet is here  http://www.centralsemi.com/PDFs/products/1N5283-5314.pdf   My boards are on the way and would greatly appreciate any input on whether the 1N5314 will work, or if anyone knows of a good sub for the 1N5313. Thanks!

 

[jdkJake]

Well, that is quite the pickle. I looked around a bit and that part is very much unavailable. Might want to contact the manufacturer to see what the issue is with availability.
 
While the 5314 might work fine "as is", I suspect you would want experiment a bit and perhaps lower the values for R5 and R6 a bit (perhaps to around 43ohm or so?).
 
I would prefer Alex to chime in and confirm any change. However, I suspect he is quite busy at the moment.
 
Any other opinions/options?