lm3875 mono blocks design - Page 2

BionicSniper · 20th March 2009, 08:18 PM

well on the noise side of things I'm using a filtered ac input module and the physical devices are going to be enclosed in metal (most likely a thin sheet of aluminum) then with another material (non metalic) around it. So the only exposed metalic surfaces would be the audio terminals which are grounded, the power switch, and the head sink which is at the very least isolated from the lm3875.

My ground system will consists of two parts. In the psu case the star point will be a bolt into the aluminum shell to which the ac ground, in case power ground, and the ground from the powercon conector from the amp (which is the ground like between the psu and amp).

In the amp I have the power ground and all of the power decoupling and bulk caps together while the input ground is connected to them via a 805 smd resistor on the pcb. The speaker return ground is just connected to the powercon ground connector. The only question that I have is should I have the ground from the feedback loop on the amp connected with the input ground or just with the power ground? And is there anything else I should do to the ac ground?

h_a · 20th March 2009, 09:59 PM

Hi,

why don't you wire it point-to-point first? There are virtually no parts

That's done in a morning and in the afternoon you can already enjoy your amp

Have fun, Hannes

BionicSniper · 20th March 2009, 11:24 PM

Well i have 4 chips coming. I may bread board it but i really don't like point to point wiring. If i'm going to do something i'm going to do it right

20th March 2009, 09:59 PM	#12
h_a diyAudio Member Join Date: Sep 2006 Location: Graz, Austria	Hi, why don't you wire it point-to-point first? There are virtually no parts That's done in a morning and in the afternoon you can already enjoy your amp Have fun, Hannes __________________ fresh matched IRFP240/IRFP9240 fets \|\| AlephJ/JX-kits F5 transistor kits \|\| Burning Amp BA-1/2/3 transistor kits

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
PP KT88 Mono blocks?	TubeMack	Tubes / Valves	38	11th June 2009 06:41 PM
100watt mono blocks	yise1	Tubes / Valves	2	27th August 2006 06:29 AM
Bridging Mono Blocks	jwatts	Tubes / Valves	8	12th February 2005 08:23 PM
Rogue 120 Mono Blocks	illenema	Tubes / Valves	0	3rd November 2003 02:17 PM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

20th March 2009, 08:18 PM	#11
BionicSniper diyAudio Member Join Date: Jul 2008 Location: Ames, Iowa	well on the noise side of things I'm using a filtered ac input module and the physical devices are going to be enclosed in metal (most likely a thin sheet of aluminum) then with another material (non metalic) around it. So the only exposed metalic surfaces would be the audio terminals which are grounded, the power switch, and the head sink which is at the very least isolated from the lm3875. My ground system will consists of two parts. In the psu case the star point will be a bolt into the aluminum shell to which the ac ground, in case power ground, and the ground from the powercon conector from the amp (which is the ground like between the psu and amp). In the amp I have the power ground and all of the power decoupling and bulk caps together while the input ground is connected to them via a 805 smd resistor on the pcb. The speaker return ground is just connected to the powercon ground connector. The only question that I have is should I have the ground from the feedback loop on the amp connected with the input ground or just with the power ground? And is there anything else I should do to the ac ground?

20th March 2009, 11:24 PM	#13
BionicSniper diyAudio Member Join Date: Jul 2008 Location: Ames, Iowa	Well i have 4 chips coming. I may bread board it but i really don't like point to point wiring. If i'm going to do something i'm going to do it right

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)