eggil Posted October 17, 2011 Report Share Posted October 17, 2011 Thank you Kerry and Ujamerstand for finding that out. And just to clarify. I wanted to use a 500V PSU, my understanding is that it's Ok to use it for the onboard version,as long as I don't use the sa1968's, but that it will run a little hot. Is This assumption correct? Quote Link to comment Share on other sites More sharing options...
kevin gilmore Posted October 17, 2011 Author Report Share Posted October 17, 2011 (edited) kerry is correct on all issues. The 500 version runs only a fraction hotter than the 450 volt version. Not an issue. I need to do some writeups for all the various different configurations. When i'm going to find the time for this, i have no idea. Edited October 17, 2011 by kevin gilmore Quote Link to comment Share on other sites More sharing options...
spritzer Posted October 17, 2011 Report Share Posted October 17, 2011 We really need to get started on those clones... Quote Link to comment Share on other sites More sharing options...
Horio Posted October 17, 2011 Report Share Posted October 17, 2011 Thanks Kerry. I had a feeling there were a few resistors I needed to change the value of. I'll get those parts ordered this week, and let you know how it works. Quote Link to comment Share on other sites More sharing options...
Horio Posted October 18, 2011 Report Share Posted October 18, 2011 I have a bunch of matched 2SK170 pairs (Idss matched at room temp) I am thinking of using on the amp boards. From your experience, how important is thermally coupling the JFET pairs? The other option would be to buy some LSK389's. Quote Link to comment Share on other sites More sharing options...
kevin gilmore Posted October 18, 2011 Author Report Share Posted October 18, 2011 you should be fine without having to glue them together. Its more important on the dynamic amps where a little DC can cause major trouble. The lsk389 does have a bit less noise. Quote Link to comment Share on other sites More sharing options...
DouglasQuaid Posted October 18, 2011 Report Share Posted October 18, 2011 When I built my reg. kgss, I set the input fets close to each other, but didn't bother gluing them. The dc offset never got too out of hand. It did move a bit more than I liked during warm-up, but it was still well within safe limits. Quote Link to comment Share on other sites More sharing options...
Horio Posted October 23, 2011 Report Share Posted October 23, 2011 (edited) Just realized there isn't a 490K for the Xicon. You can use the 487K or you can leave the 442K and switch the 20K to an 18K. Either will get you close to 500V. I swapped out R6 and R16 with 18K resistors (left R5, R15, R29, R30 at 442K), and I'm now getting +/-504V. The bias is also nice and stable at 580V without the voltage multiplier. Seems like my 500V power supplies are working well. Edited October 23, 2011 by Horio Quote Link to comment Share on other sites More sharing options...
kevin gilmore Posted October 23, 2011 Author Report Share Posted October 23, 2011 That is better than 1% accuracy which is all you should expect unless you get silly and hand match the parts. Quote Link to comment Share on other sites More sharing options...
TMoney Posted October 23, 2011 Report Share Posted October 23, 2011 Great job, Greg. Sounds like you are getting close to having them make a little music. Quote Link to comment Share on other sites More sharing options...
Kerry Posted October 24, 2011 Report Share Posted October 24, 2011 Great job. Congratulations Quote Link to comment Share on other sites More sharing options...
Horio Posted October 25, 2011 Report Share Posted October 25, 2011 Got my panels back from Front Panel Express, and they look great. I had them do the drilling/tapping for the heatsink mounted semi's. I'll try and post some pictures of that setup this weekend, when I start assembling the amp. Here's the front panel (thanks to ujamerstand for the layout). Quote Link to comment Share on other sites More sharing options...
ujamerstand Posted October 25, 2011 Report Share Posted October 25, 2011 hotdamn. They turned out great! How does the stax jack fit from the back? Quote Link to comment Share on other sites More sharing options...
n3rdling Posted October 25, 2011 Report Share Posted October 25, 2011 Theres a typo I just noticed..."Electostatic"...missing 'r'. Looks nice though! Quote Link to comment Share on other sites More sharing options...
livewire Posted October 25, 2011 Report Share Posted October 25, 2011 Oopsie! Quote Link to comment Share on other sites More sharing options...
ujamerstand Posted October 25, 2011 Report Share Posted October 25, 2011 ... Just noticed it on my panel too. Man, that's an $120 mistake right there. Damn. Quote Link to comment Share on other sites More sharing options...
kevin gilmore Posted October 25, 2011 Author Report Share Posted October 25, 2011 (edited) electo-static. I can live with that. nothing a little stickon with a ^ and a tilted R won't fix. Edited October 25, 2011 by kevin gilmore Quote Link to comment Share on other sites More sharing options...
Horio Posted October 25, 2011 Report Share Posted October 25, 2011 (edited) Theres a typo I just noticed..."Electostatic"...missing 'r'. Looks nice though! Oh snap! Not sure how I missed that one... I must have been to worried about the cavities and all the holes lining up correctly. Oh well. The stack jack fits great on the rear side of the panel. The blind tapped holes all lined up perfectly. Edited October 25, 2011 by Horio Quote Link to comment Share on other sites More sharing options...
chinsettawong Posted October 25, 2011 Report Share Posted October 25, 2011 Nice front panel! Quote Link to comment Share on other sites More sharing options...
cobra_kai Posted October 25, 2011 Report Share Posted October 25, 2011 Nice job on the panel. What are all of the epsilon 24s for? Quote Link to comment Share on other sites More sharing options...
Horio Posted October 25, 2011 Report Share Posted October 25, 2011 The epsilon 24's are going to run the anti-vandal momentary power switch and power relay. Quote Link to comment Share on other sites More sharing options...
deepak Posted October 25, 2011 Report Share Posted October 25, 2011 Looks great Greg. I looked at Yun's numerous panel layouts a few times and I never noticed the typo either (reminds me of that psychology trick where the mind will read the words properly as long as the first and last letters of most words are correct) Guess we'll be taking a microscope and have our glasses on for the T2 one Quote Link to comment Share on other sites More sharing options...
johnwmclean Posted October 25, 2011 Report Share Posted October 25, 2011 I like the font chosen for “KGSSHV” and “AMPLIFIER”. Quote Link to comment Share on other sites More sharing options...
jantze Posted October 25, 2011 Report Share Posted October 25, 2011 Electostatic amplifiers goes to eleven! I like the front panels, too. Well done! Quote Link to comment Share on other sites More sharing options...
ujamerstand Posted October 25, 2011 Report Share Posted October 25, 2011 Electostatic amplifiers goes to eleven! Heh, you noticed. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.