Hi,
I have made some first listening tests with my 5 channel gainclone. LM3875T is in noninverting mode, and PCB uses mostly SMD components to make shortest signal path. Also signal side has own ground to star grounding point.
In first tests, there is no any audible mains hum. Also i cant hear any noise. I think that my Yamaha integrated amplifier is more noisy than GC. I have to make some performance measurements when i got whole amplifier ready. Now i have use only MAIN channels.
And sound: First time i can hear difference between amplifiers. GC makes much better stereo image, especially now i can hear that music has third dimension, depth (i hope u understand what i mean 🙂. Only bad thing is that in lower frequencies hasnt power so much than my Yamaha. -3dB point is about 7Hz, so i think bandwith isnt problem for that. Mids and highs i cant hear any big difference.
I will use all 5 channels in my home theater system. Im using two separate MAIN channels for listening music. I have two 250VA transformers, one for MAIN-channels and other to three for surround channels.
I have made some first listening tests with my 5 channel gainclone. LM3875T is in noninverting mode, and PCB uses mostly SMD components to make shortest signal path. Also signal side has own ground to star grounding point.
In first tests, there is no any audible mains hum. Also i cant hear any noise. I think that my Yamaha integrated amplifier is more noisy than GC. I have to make some performance measurements when i got whole amplifier ready. Now i have use only MAIN channels.
And sound: First time i can hear difference between amplifiers. GC makes much better stereo image, especially now i can hear that music has third dimension, depth (i hope u understand what i mean 🙂. Only bad thing is that in lower frequencies hasnt power so much than my Yamaha. -3dB point is about 7Hz, so i think bandwith isnt problem for that. Mids and highs i cant hear any big difference.
I will use all 5 channels in my home theater system. Im using two separate MAIN channels for listening music. I have two 250VA transformers, one for MAIN-channels and other to three for surround channels.
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Let's just ask if Mika is willing to share his PCB design..... The Straight and Honest approach if you ask me.
Very good looking PCB !!
Very good looking PCB !!
Member
Joined 2002
I already did no reply though. i want to do one of his boards for my friend. Hope i can either buy a board or get a pcb layout.
jean-paul said:
Actually, I just want to know what CAD software he's using...but if you want his PCB artwork, you can go ahead and ask...
Im using quite old version of Protel software, ISIS for schematics and ARES for PCB. I will made some little improvements to board, some changes to trace widths and signal path grounding. Those changes are just finishing, not any big changes.
If anyone wants, i can send protel files via email. Also i can make website, where you can find schematic, PCB layout and parts list as image if you dont have protel software. Website takes few days to make.
Some information: PCB size is 160x100mm. All SMD components uses 0805 packages with littlebit larger pads to make solder easier. Electrolytic capasitors uses 16mm can (im using 1000uF/50V) .
This amplifier is part of a bigger project, where i build whole home theater system. It uses this amplifier and now im building pre-amplifier with 6 channel analog input. Preamplifier consists 3xCS3310 digital potentiometer (not PGA2310 because i cant get those), Hitachi LCD, powersupply and PIC16F877 microcontroller. Software has little menu, where user can change all six speakers levels +/-8dB. Of course software also adjust all levels at same time as volume 🙂
If anyone wants, i can send protel files via email. Also i can make website, where you can find schematic, PCB layout and parts list as image if you dont have protel software. Website takes few days to make.
Some information: PCB size is 160x100mm. All SMD components uses 0805 packages with littlebit larger pads to make solder easier. Electrolytic capasitors uses 16mm can (im using 1000uF/50V) .
This amplifier is part of a bigger project, where i build whole home theater system. It uses this amplifier and now im building pre-amplifier with 6 channel analog input. Preamplifier consists 3xCS3310 digital potentiometer (not PGA2310 because i cant get those), Hitachi LCD, powersupply and PIC16F877 microcontroller. Software has little menu, where user can change all six speakers levels +/-8dB. Of course software also adjust all levels at same time as volume 🙂
Member
Joined 2002
Mika i'm glad to hear that you will share. If you need the web-space let me know i got lots and a static ip. : O ) Im interested in all your ideas.
Mika said:
I would not mind if you send me this files via email =) planning to build a 5ch for my computer, it will save me some time =)
Mika, schuro.de has PGA2310's listed on their site. I'm sure they'll ship to Finland if you're interested.
/U.
/U.
Member
Joined 2002
theChris: There is 100nF capacitors on voltage rails, but they are SMD and that picture doesnt show bottom mask.
Member
Joined 2002
Can i perchase a board from you.? or can you email me the protel file. ? or .jpg so i can etch my own board. ?
PLEASE : O )
PLEASE : O )
Hi all again,
Now i have made web pages where you can find some information of my amp. My skill to make webpages isnt any good, but i hope pages will work. Also remember that english isnt my mother tonque 🙂
http://www.sunpoint.net/~crypton/5ch.htm
Now i have made web pages where you can find some information of my amp. My skill to make webpages isnt any good, but i hope pages will work. Also remember that english isnt my mother tonque 🙂
http://www.sunpoint.net/~crypton/5ch.htm
Mika,
I really like the idea Of a 5ch with 3886s and was wondering if you could e-mail me the jpg file of just the copper in black and white, anotherwords, with no component markings? And with no blue and purple?
Thank you so much, Mike
mike34341@netzero.net
I really like the idea Of a 5ch with 3886s and was wondering if you could e-mail me the jpg file of just the copper in black and white, anotherwords, with no component markings? And with no blue and purple?
Thank you so much, Mike
mike34341@netzero.net
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