I got sidetracked a bit experimenting recently with those drivers: http://www.diyaudio.com/forums/showthread.php?s=&threadid=69176&highlight=fal
but I will look into USB DAC soon.
but I will look into USB DAC soon.
peter when i order that kit next week can i get a LM4780 ic off of you? i think i have been a victim of static damage. i was moving the amplifier to another room and i have electric heat so its very dry here. and there was a spark from my finger to the left rca when i was pluging in the source. i powered it up that channel is dead everying tests good just no input weird. this is a first for me
working with chipamps
.
extra few bucks?
thanks
working with chipamps
.extra few bucks?
thanks
It is R1 on the board (220R in premium kit). You can short it with a piece of wire and effectively remove it from a circuit. I'm not using those resistors in the Patek amps, and it works fine. You'll gain a bit more of clarity and if the amp does not oscillate you can leave it like that (may be depend on the rest of a system).
Hello again Peter,
It’s unfortunate that the LM3875 sounds better, as it is less powerful then the LM4780. I take it that two LM4780 boards can be bridged and then balanced with the xlr to 2rca cable. That would be like 200W at 4ohms at about 27V (I didn’t calculate it’s just a ballpark guess). I don’t have any high efficiency speaker that’s why I ask.
Because the LM3875 sounds better would it be possible take your LM4780 Amplifier bridged Schematic and replace the amp with two LM3875s’s (I can draw it for you if you don’t understand what a mean). I know there are a lot of circuits out there to do this already however many of them seem like compromises. The extra benefit of this arrangement would be, if it works, better heat dissipation as all the chip dies are in separate packages. Of course it may be better to just use the LM4780 as you already have the boards ready to sell.
Leve,
Oh no it’s another power hungry amp builder.
It’s unfortunate that the LM3875 sounds better, as it is less powerful then the LM4780. I take it that two LM4780 boards can be bridged and then balanced with the xlr to 2rca cable. That would be like 200W at 4ohms at about 27V (I didn’t calculate it’s just a ballpark guess). I don’t have any high efficiency speaker that’s why I ask.
Because the LM3875 sounds better would it be possible take your LM4780 Amplifier bridged Schematic and replace the amp with two LM3875s’s (I can draw it for you if you don’t understand what a mean). I know there are a lot of circuits out there to do this already however many of them seem like compromises. The extra benefit of this arrangement would be, if it works, better heat dissipation as all the chip dies are in separate packages. Of course it may be better to just use the LM4780 as you already have the boards ready to sell.
Leve,
Oh no it’s another power hungry amp builder.
Hi,
The difference between both chips is not really that big. I was using for at least 2 months LM4780 amp in stereo configuration then I switched to bridged setup (same chip) and I liked them both. It is a matter of deeper refinement and it is not always that obvious and greatly depends on the rest of the system. After few months of using LM4780 in bridged mode, I switched not to LM3875 in bridged mode and the difference is rather subtle.
Besides, two bridged LM3875 seem indeed more powerful. The bridging schematic for LM4780 aplies equally well to LM3875.
If you really need power, go with a bigger chip, you shouldn't be disappointed.
The difference between both chips is not really that big. I was using for at least 2 months LM4780 amp in stereo configuration then I switched to bridged setup (same chip) and I liked them both. It is a matter of deeper refinement and it is not always that obvious and greatly depends on the rest of the system. After few months of using LM4780 in bridged mode, I switched not to LM3875 in bridged mode and the difference is rather subtle.
Besides, two bridged LM3875 seem indeed more powerful. The bridging schematic for LM4780 aplies equally well to LM3875.
If you really need power, go with a bigger chip, you shouldn't be disappointed.
The buffer boards I described here: http://www.diyaudio.com/forums/showthread.php?postid=748650#post748650 are already fabricated. As soon as I test them, they will be available (it will be at least 10 days before I receive them though).
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Hi Peter
Is the site down for some reason?
How long do you think it would take from Canada till the kits get here?
I have a couple of 4780s lying around, I want a 4 way amp (bridge/parallel) so I was wondering if I could customise my order a bit or you are pretty fixed as far as kit order goes. I basically need 4 complete amps and I already have 2 chips, and I would love to get my hands on some good passives (Hint - Riken/Caddock/BG in exchange for two chips - I'm just being a miser here but I need to $ave)...
And why can't I access the site?
Is the site down for some reason?
How long do you think it would take from Canada till the kits get here?
I have a couple of 4780s lying around, I want a 4 way amp (bridge/parallel) so I was wondering if I could customise my order a bit or you are pretty fixed as far as kit order goes. I basically need 4 complete amps and I already have 2 chips, and I would love to get my hands on some good passives (Hint - Riken/Caddock/BG in exchange for two chips - I'm just being a miser here but I need to $ave)...
And why can't I access the site?
Attachments
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