| DCAudioDIY.com http://www.dcaudiodiy.com/phpBB3/ |
|
| GM-70 Amplifier http://www.dcaudiodiy.com/phpBB3/viewtopic.php?f=4&t=595 |
Page 2 of 10 |
| Author: | dberning [ February 19th, 2016, 10:31 am ] |
| Post subject: | Re: GM-70 Amplifier |
Beautifully constructed amp, Dave. With the weather the way it is, I am sure that you can get the second one done shortly. Look forward to hearing it. David Berning |
|
| Author: | David McGown [ February 22nd, 2016, 9:13 am ] | |||
| Post subject: | Re: GM-70 Amplifier | |||
Made good progress on the second amp this weekend. Nothing like the motivation of a completed and nice sounding amp, and looking forward to stereo. A couple of in-progress shots.
|
||||
| Author: | Stuart Polansky [ February 22nd, 2016, 10:04 am ] |
| Post subject: | Re: GM-70 Amplifier |
Pictures don'e do this amp justice. It is MUCH bigger in person than it appears. It sounds amazingly powerful, and is of course, constructed with David's usual meticulous craftsmanship. The choke, power transformer and oil caps are enormous! Great build David! |
|
| Author: | KLH007 [ February 22nd, 2016, 12:59 pm ] |
| Post subject: | Re: GM-70 Amplifier |
Another beautifully made amp, great work David! |
|
| Author: | Grover Gardner [ February 23rd, 2016, 1:52 am ] |
| Post subject: | Re: GM-70 Amplifier |
Terrific, Dave! Glad you were able to put that iron to good use! |
|
| Author: | David McGown [ February 23rd, 2016, 8:39 am ] | ||
| Post subject: | Re: GM-70 Amplifier | ||
Another progress report. Wanted to show the copper ground buss for the power supply, since that is hidden from view when the amp is fully assembled. Using 22 or 24 gauge (don't remember offhand) copper sheet, cut down to 1" wide strips running from the HV power transformer to the capacitor terminals, and finally to the input jack. Using bronze external tooth lock washers between the terminal and each buss layer to ensure a good mechanical/electrical connection when the terminal nut is torqued down.
|
|||
| Author: | Stuart Polansky [ February 23rd, 2016, 8:46 am ] |
| Post subject: | Re: GM-70 Amplifier |
David, I'm surprised, the clamp screws for two of those oil caps are installed in opposite directions. Tsk, tsk! Laugh out loud, even David is not perfect. I can sleep better at night knowing that!  
|
|
| Author: | ratbagp [ February 23rd, 2016, 8:51 am ] |
| Post subject: | Re: GM-70 Amplifier |
What a great idea for those of us who use wood for the top plate. I have a bunch of these copper strips that I could use though I suppose a single run like you have done would be better. http://www.leevalley.com/US/gifts/page.aspx?p=10459&cat=4,104,53211,10459 ray |
|
| Author: | tomp [ February 23rd, 2016, 10:10 am ] |
| Post subject: | Re: GM-70 Amplifier |
Have you ever thought of lining the inside of the wood case with copper screen? I have done that in low level applications to create a Faraday cage. It is a great way to keep out RF if you ground it. Tom |
|
| Author: | David McGown [ February 23rd, 2016, 10:33 am ] |
| Post subject: | Re: GM-70 Amplifier |
Quote: Have you ever thought of lining the inside of the wood case with copper screen? I have done that in low level applications to create a Faraday cage. It is a great way to keep out RF if you ground it. Tom Tom, I have never had a problem with power amps and RF using my wood chassis construction. Low level (phono stages) are a problem, and I have used copper shielding with wooden chassis in those cases, but even with a metal enclosure grounded to earth, I have problems with the ham radio operator up the street. When he is working his rig, then I fall back to digital. David |
|
| Page 2 of 10 | All times are UTC - 5 hours [ DST ] |
| Powered by phpBB® Forum Software © phpBB Group https://www.phpbb.com/ |
|