can anyone tell me what is the exact value of R6 ,is it 10R 500mw or 4R7 1watt
coz i found some use 10ohm and some use 4.7ohm , please tell the exact wattage .
coz i found some use 10ohm and some use 4.7ohm , please tell the exact wattage .
hello AndrewT
This is the link of schematic on page 5 ,thanks http://www.diyaudio.com/forums/atta...9521632-lm3886-schematics-pcb-apex-lm3886.jpg
R6 is the Output Zobel resistor part.
Apex has changed from the National Value of 2r7, to what he thinks works for his implementation.
Most builders find that R6 in any power amplifier, not just 3886, is not critical for value.
Try anything from 2r7 to 10r.
But ensure you have sufficient dissipation capability to suit the way you test your amplifiers.
I often use 20r||20r||20r||20r or
series parallel 10r||10r + 10r||10r
or lots of other combinations of 600mW resistors.
Apex has changed from the National Value of 2r7, to what he thinks works for his implementation.
Most builders find that R6 in any power amplifier, not just 3886, is not critical for value.
Try anything from 2r7 to 10r.
But ensure you have sufficient dissipation capability to suit the way you test your amplifiers.
I often use 20r||20r||20r||20r or
series parallel 10r||10r + 10r||10r
or lots of other combinations of 600mW resistors.
Last edited:
A 3d representation of Apex Gainclone. Just for fun.
Gainclone City - A 3d representation of Apex Gainclone. Just for fun.
Thank you Mr. Slavkovic. 🙂
A short video:
http://www.youtube.com/watch?v=mvK8z2FjgHY
🙂
Gainclone City - A 3d representation of Apex Gainclone. Just for fun.
Thank you Mr. Slavkovic. 🙂
A short video:
http://www.youtube.com/watch?v=mvK8z2FjgHY
🙂
Attachments
Thank you. 🙂
And after building some 10 apex gainclones, I could not resist myself to create the 3d model this in a virtual immersive environment . 🙂
Thank you so much Mike for your feedback. At present I am using 6 sets of apex gainclone in my 3 way active amplifier system. And I love the sound, I must say. I tried the elector circuit too but I prefer Apex's circuit.
And after building some 10 apex gainclones, I could not resist myself to create the 3d model this in a virtual immersive environment . 🙂
Hello friends
Finally my apex LM3886 amplifier working after many difficulties. I think Problems is fake chip. Because when I replaced with Sample I got from National semiconductor. Amp started working perfectly. Can I connect supply ground to metal case and then connect this ground on Amp PCB ground.Is this LM3886 amplifier required pre-amplifier. Can anyone suggest simple Tone control or pre-amplifier for this amplifier.
Finally my apex LM3886 amplifier working after many difficulties. I think Problems is fake chip. Because when I replaced with Sample I got from National semiconductor. Amp started working perfectly. Can I connect supply ground to metal case and then connect this ground on Amp PCB ground.Is this LM3886 amplifier required pre-amplifier. Can anyone suggest simple Tone control or pre-amplifier for this amplifier.
I have problem ,I made this amp work perfectly few days I was using it with pre amp , yesterday when i remove pre amp and connect direct computer out amp started to humming (very loud)and after that no sound from speaker, when i check output
it shows 28v in dc also i found that speaker is dead .can anyone help me why this happen .
it shows 28v in dc also i found that speaker is dead .can anyone help me why this happen .
Chip killed by the static from PC and the input resistor is too big, 10k-22k would be ok but 100k is too much. That design is not that good..
But the resistor value doesnt change much.
But the resistor value doesnt change much.
Hello Mihkus , Which input register you are talking about ? according to digram
i think input register is 1k ohm , please explain further.
Hi,
I want to build this amp because it's made with an high quality IC, but I only need a few watts. My friends told me that I have 2 variants: to lower the supply voltage or to decrease the amplification. But some of them say that this IC will sound worst if powered from a lower (than +/-28Vdc) power supply... and others say that if I decrease the gain the IC will be unstable. I don't know what to do... Maybe a little decrease of both voltage and gain ? What do yo advise me ?
I want to build this amp because it's made with an high quality IC, but I only need a few watts. My friends told me that I have 2 variants: to lower the supply voltage or to decrease the amplification. But some of them say that this IC will sound worst if powered from a lower (than +/-28Vdc) power supply... and others say that if I decrease the gain the IC will be unstable. I don't know what to do... Maybe a little decrease of both voltage and gain ? What do yo advise me ?
You could still use the same IC and power supply and simply replace the feedback resistor with a lower value to give you less gain.