Vorpal,
I built a six channel last year using three chips and three ps with two transformers.(23 +23,400va from Antek). I am going to rebuild again this year adding two parallel channels plus two active x-overs.
These chipamps are excellent with great clarity and power! I upgraded from a Rotel amp and noticed a big difference!
I have aproblem with a ground loop but it is because I used two ps for one trannie, When I rebuild,I will use only one ps per trannie and it should take care of the ground loop issue. Check out the chipamp threads, there are plenty of threads on this issue with a recent one definitely showing that one ps per trannie will stop ground loops.
So all in all, I highly recommend Peter's kits! Easy to follow instructions. I bought my trannies from Antek from e-bay though I noticed Peter sells Plitrons.
I built a six channel last year using three chips and three ps with two transformers.(23 +23,400va from Antek). I am going to rebuild again this year adding two parallel channels plus two active x-overs.
These chipamps are excellent with great clarity and power! I upgraded from a Rotel amp and noticed a big difference!
I have aproblem with a ground loop but it is because I used two ps for one trannie, When I rebuild,I will use only one ps per trannie and it should take care of the ground loop issue. Check out the chipamp threads, there are plenty of threads on this issue with a recent one definitely showing that one ps per trannie will stop ground loops.
So all in all, I highly recommend Peter's kits! Easy to follow instructions. I bought my trannies from Antek from e-bay though I noticed Peter sells Plitrons.
To turn the amp on,I have a 120vac relay which is plugged into my reciever, so when the reciever turns on it trips the relay, turning the amp on.
Depending on what "ohm" speakers you have will depend on what configuation you can do. Use on chip for two channels for 8 ohm speakers and use one chip in parallel for 4 ohm speakers.
So you would need anywhere from 1 1/2 kits to 3 full kits.
As for watts/channel, my amp delivers an unknown amount of watts(maybe 60-70) but compared to my old Rotel @ 150w/channel, this chipamp is no slouch!It goes louder with less distortion!
If you go to HTGuide.com and search out gainclone, you will find my 6 ch amp there. I go by the same name there.
Depending on what "ohm" speakers you have will depend on what configuation you can do. Use on chip for two channels for 8 ohm speakers and use one chip in parallel for 4 ohm speakers.
So you would need anywhere from 1 1/2 kits to 3 full kits.
As for watts/channel, my amp delivers an unknown amount of watts(maybe 60-70) but compared to my old Rotel @ 150w/channel, this chipamp is no slouch!It goes louder with less distortion!
If you go to HTGuide.com and search out gainclone, you will find my 6 ch amp there. I go by the same name there.
I finally got my two ALL-In-One DACs put in cases....one black, one Alodine Clear. I retrofitted Tent Labs XO-DACs at 2.8224MHz, added power switches and power indicator LEDs. I've left room for Peter's USB adapter board and a selector switch.
I powered the XO-DAC from one leg of the on-board PSU and the LED from the other....seems not to cause a problem....what do you think Peter? Should I add another PSU? Also, when the USB board is added, can it run off the same PSU?
Photo1 Photo2 Photo3 Photo4
I powered the XO-DAC from one leg of the on-board PSU and the LED from the other....seems not to cause a problem....what do you think Peter? Should I add another PSU? Also, when the USB board is added, can it run off the same PSU?
Photo1 Photo2 Photo3 Photo4
rjkdivin said:
Looks good. I would run the XO-DAC from the same supply as CS8412, same for the LED, but connected directly to the first cap (C3). That will provide some filtering and separation between DAC and the additonal circuit. I understand XO-DAC comes with on board regulators, so it should work fine this way.
Hi,
recently, i constructed another chipamp using Peter's boards and with similar connection as the Patek (with cheaper parts) ...
Unfortunately, there is no sond comming out of speakres except significant buzz in th eright speaker - the left channel is totally silent. I also noticed that the chip on buzzing channel is getting very very hot...
any idea what the trouble might be?
Thanks.
recently, i constructed another chipamp using Peter's boards and with similar connection as the Patek (with cheaper parts) ...
Unfortunately, there is no sond comming out of speakres except significant buzz in th eright speaker - the left channel is totally silent. I also noticed that the chip on buzzing channel is getting very very hot...
any idea what the trouble might be?
Thanks.
Attachments
The trace from pin 12 of the CS8412 is cut on the back of the PCB. The XO-DAC input wire is taken from the CS-8412, and its output is taken to pin 1 of the TDA1543. This replaces the clock output of the CS0412 with the clock from the XO-DAC. The grounds for the input and output of the XO-DAC are taken together to the ground trace in the signal circuit of the AllInOne....I used the ground pad for the analog out RCA jacks. Guido Tent's documentation for the XO-DAC is quite good.lordvader said:
Robert
LM4780 Mute resistor
This being my first experience with a SMD ...
I dropped one on my black floor and it is limpossible to find (so far).
Is it important for this SMD component to be used or could one use a CADDOCK (I am sure this is overkill in the extreme, but, at least, the pins are easier to fit the pad)?
Thanks,
This being my first experience with a SMD ...
I dropped one on my black floor and it is limpossible to find (so far).
Is it important for this SMD component to be used or could one use a CADDOCK (I am sure this is overkill in the extreme, but, at least, the pins are easier to fit the pad)?
Thanks,
Well...i've finished my gainclone power amp!
When i turned it on and played one test cd my face was like that ->
I tell more later about sound when i do some serious listening not 3 min's and btw there was absolutely no hum at all...dead silent it is.
Pictures are here:
http://dap.noworkteam.nl/gc/gc.php
(click on the white buttons!)
Thanks so much Peter for this great kit, love it. This is THE POWERAMP!
Ronald
When i turned it on and played one test cd my face was like that ->
I tell more later about sound when i do some serious listening not 3 min's
and btw there was absolutely no hum at all...dead silent it is.Pictures are here:
http://dap.noworkteam.nl/gc/gc.php
(click on the white buttons!)
Thanks so much Peter for this great kit, love it. This is THE POWERAMP!
Ronald
LM4780 Parallel Issues
Greetings,
I have finally had some time to tinker with my LM4780 monos from Peter, and I am having some issues I hope someone can help me out with. I am running the amps in parallel configuration.
Question 1- The amps initally had high DC offset in the 200mV range, but I found this may be due to my preamp as the input has around 3-4mV of DC on it, when I run directly from my DAC the offset at output drops to 20-30mV and there is 0 DC at input. Would I be correct in assuming I should try the Zobel components to cure this? Any recommendations on what type of caps and resistors are best to use here?
Question 2- I am driving relatively difficult speakers, they dip to around 2.5 ohms, but even at moderately loud levels the amps protection circuits are kicking in and they shut off intermittently during loud passages. I cannot find anything that would be causing this other than possible overheating, but the heatsinks are not what I would consider hot. At least I can touch them with my hand and it is not uncomfortable. I am using 1mil kapton tape and a thin layer of thermal grease, heatsinks are tapped and I have screws run directly into it. Any thoughts on why this may be happening? Are my speakers just too difficult of a load? Do I need to place a bar across the chip to get more pressure to the heatsink? I am using 22v 300va Plitrons for each amp, shouldn't be any issues with under/over voltage?
Thanks
Sam
Greetings,
I have finally had some time to tinker with my LM4780 monos from Peter, and I am having some issues I hope someone can help me out with. I am running the amps in parallel configuration.
Question 1- The amps initally had high DC offset in the 200mV range, but I found this may be due to my preamp as the input has around 3-4mV of DC on it, when I run directly from my DAC the offset at output drops to 20-30mV and there is 0 DC at input. Would I be correct in assuming I should try the Zobel components to cure this? Any recommendations on what type of caps and resistors are best to use here?
Question 2- I am driving relatively difficult speakers, they dip to around 2.5 ohms, but even at moderately loud levels the amps protection circuits are kicking in and they shut off intermittently during loud passages. I cannot find anything that would be causing this other than possible overheating, but the heatsinks are not what I would consider hot. At least I can touch them with my hand and it is not uncomfortable. I am using 1mil kapton tape and a thin layer of thermal grease, heatsinks are tapped and I have screws run directly into it. Any thoughts on why this may be happening? Are my speakers just too difficult of a load? Do I need to place a bar across the chip to get more pressure to the heatsink? I am using 22v 300va Plitrons for each amp, shouldn't be any issues with under/over voltage?
Thanks
Sam
The amp will amplify DC if it's present at the input, if your source produces any offset (even 3-4 mV, it's best to use a coupling cap; 4.7uF is fine and BG N will work here well).
Zobel will not help with DC offset issues. If you want to try Zobel, you can use 0.1uF and 2.7R (for Cz/Rz) or 0.01uF and 10R ( as those the values that 47Labs uses).
2.5 ohm speaker load should not be a problem for parallel 4780 chip. If you heatsinks are large enough, there shouldn't be any dissipation issues either. What I can only think about now, is maybe the heat transfer from a chip to the heatsink is not good enough. Can you check temp of the chip itself, maybe the bar would help here indeed?
Zobel will not help with DC offset issues. If you want to try Zobel, you can use 0.1uF and 2.7R (for Cz/Rz) or 0.01uF and 10R ( as those the values that 47Labs uses).
2.5 ohm speaker load should not be a problem for parallel 4780 chip. If you heatsinks are large enough, there shouldn't be any dissipation issues either. What I can only think about now, is maybe the heat transfer from a chip to the heatsink is not good enough. Can you check temp of the chip itself, maybe the bar would help here indeed?
Banned
Joined 2002
Any Philips remote works with this circuit. I suggested Veteran to come up with new display module that is compatible with LED matrix displays. 4 digit modules (as used in Mark Levinson preamps) cost approx $25, are readily available from Digi Key and still look better than all those fancy displays you see these days. I'm not sure if he finalized the design yet.
http://www.marklevinson.com/image_library/380SFP_lo.jpg
http://www.marklevinson.com/image_library/380SFP_lo.jpg
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