It is obviously possible but, IMHO, it wouldn't be any better.
On the contrary the LM3886 PS of the FE makes use of not commonly used PCB techniques (in DIY audio pcbs) like striplines which are supposed to improve his performance.
I don't have the equipment to measure those differences but FE's subjective results seem to confirm my choice
Also, KSTR tested (measured) FE beta boards with good results regarding EMI performance of the PS and the board in geenral.
Sorry, wrong therm, the right one is Microstrip.
The advantage is that impedance is (almost) constant (so less reflections and distortion), radiates (and picks up) less, and inductance is reduced by 40%.
Thanks for the explanation, I learned yet another thing.
I've just read a part of a long discussion on power supplies by some distinguished members of this forum, and the conclusion is that best power supplies are NOT built on separate boards, but comprise of putting the capacitors as close to the ICs or transistors as possible, calculating trace R and L, paralleling the right value caps etc...
A long read, but they actually quantified the reasons why their amps sound better, and some of which coincide with the FE version optimizations. I'll get back to reading now...
I've just read a part of a long discussion on power supplies by some distinguished members of this forum, and the conclusion is that best power supplies are NOT built on separate boards, but comprise of putting the capacitors as close to the ICs or transistors as possible, calculating trace R and L, paralleling the right value caps etc...
A long read, but they actually quantified the reasons why their amps sound better, and some of which coincide with the FE version optimizations. I'll get back to reading now...
Two topics actually, this is the first:
http://www.diyaudio.com/forums/solid-state/90728-bob-cordell-interview-power-supplies.html
And this one (maybe even better):
http://www.diyaudio.com/forums/power-supplies/216409-power-supply-resevoir-size.html
In this particular post from the second topic you have a few more links:
http://www.diyaudio.com/forums/power-supplies/216409-power-supply-resevoir-size-3.html#post3097232
Hundreds of pages, enjoy
http://www.diyaudio.com/forums/solid-state/90728-bob-cordell-interview-power-supplies.html
And this one (maybe even better):
http://www.diyaudio.com/forums/power-supplies/216409-power-supply-resevoir-size.html
In this particular post from the second topic you have a few more links:
http://www.diyaudio.com/forums/power-supplies/216409-power-supply-resevoir-size-3.html#post3097232
Hundreds of pages, enjoy
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Deleted member 148505
Was able to test the amp today, I got 45Watts into 4 ohms resistive dummy load using 8Amps 24-0-24VAC transformer. (Single channel driven)
As for the sound, It has a wide soundstage and superb detail, the instruments sounded lively.
I compared it to my LM3875, this one has more detail and the bass has more punch. The LM3875 is much softer/smoother though.
For me the sound character is much like BAKSA 50 but with more refinement, more details and more accurate bass.
As for the sound, It has a wide soundstage and superb detail, the instruments sounded lively.
I compared it to my LM3875, this one has more detail and the bass has more punch. The LM3875 is much softer/smoother though.
For me the sound character is much like BAKSA 50 but with more refinement, more details and more accurate bass.
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Hi,
That's a very nice build by the way.
I'm new to Chip amps. I'm going to build a simple version first to see how it goes. But it's interesting to read about other designs. This design appears to use the LM3886 as a current driver and another opamp for the voltage gain.
So when listening to this amplifier I assume that it is the LM318 that 'sets the tone' for the sound and not the LM3886 ?
That's a very nice build by the way.
I'm new to Chip amps. I'm going to build a simple version first to see how it goes. But it's interesting to read about other designs. This design appears to use the LM3886 as a current driver and another opamp for the voltage gain.
So when listening to this amplifier I assume that it is the LM318 that 'sets the tone' for the sound and not the LM3886 ?
Was able to test the amp today, I got 45Watts into 4 ohms resistive dummy load using 8Amps 24-0-24VAC transformer. (Single channel driven)
As for the sound, It has a wide soundstage and superb detail, the instruments sounded lively.
I compared it to my LM3875, this one has more detail and the bass has more punch. The LM3875 is much softer/smoother though.
For me the sound character is much like BAKSA 50 but with more refinement, more details and more accurate bass.
so which layout did you use? is it on the post #31?
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Deleted member 148505
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Deleted member 148505
I had a request from a friend in a local forum to create a My Ref Rev C layout which uses an LM318 supply similar to fremen, and putting ample space for input capacitor. I also provided a jumper (computer motherboard/harddisk jumper) so that the input capacitor can be bypassed easily. This one also uses a better circuit for speaker protect.
Size: 3.9" x 3.9"
PS: For my personal use only, not for sale. Only showed here for gallery purpose.
Size: 3.9" x 3.9"
PS: For my personal use only, not for sale. Only showed here for gallery purpose.
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I understand boards are for your personal use, nevertheless it would have been nice to see credit to Mauro Penasa... at least.
D
Deleted member 148505
Yes, my bad.
Next time I'll put mauro penasa's name on it.
There's really no more space on the top pcb that is visible when all components are soldered. So I can't put all the credits for the parts of the circuit.
D
Deleted member 148505
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D
Deleted member 148505
Not yet finished, still missing some parts, it's not much of a priority right now, because I'm still enjoying my IRS2092 based class-d amp for my main speakers.
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