😳
Eh, that are super regulators that keep rails modulation at uV levels, even at full power or any frequency.
I'm going to make Babelfish F8m
all parts mosfets, all in TO247 case, well, except optocoupler
......but TN2640 is TO-92 (or smd package)......not TO-247?
https://ww1.microchip.com/downloads...de-Vertical-DMOS-FET-Data-Sheet-20005795A.pdf
https://ww1.microchip.com/downloads...de-Vertical-DMOS-FET-Data-Sheet-20005795A.pdf
I spent some time stuffing the small resistors into the B-F8 PCBs.
I noticed a 15R GBR resistor to form an input signal Gnd. I guess the 15R is "default" option instead of just a "shot" to Power/Speaker Gnd.
In my case I will have Chassis Gnd, Power/Speaker Gnd, Input Gnd. I have the usual NTC from Power/Speaker Gnd to Chassis/Safety Gnd.
Think it will be fine. I just don't remember to have seen the GBR resistor in other power amp designs.
I noticed a 15R GBR resistor to form an input signal Gnd. I guess the 15R is "default" option instead of just a "shot" to Power/Speaker Gnd.
In my case I will have Chassis Gnd, Power/Speaker Gnd, Input Gnd. I have the usual NTC from Power/Speaker Gnd to Chassis/Safety Gnd.
Think it will be fine. I just don't remember to have seen the GBR resistor in other power amp designs.
if you have dual mono arrangement, GBR can be 0R
if you have common PSU, make it 15R
that trick is older than me
if you have common PSU, make it 15R
that trick is older than me
I build dual mono but I guess the 15R will not "hurt"?
I have not soldered anything yet so easy to change the 15R to a short if that is recommended.
I have not soldered anything yet so easy to change the 15R to a short if that is recommended.
A little bit further with mounting. Maybe the rest for the weekend!
Regarding facing the resistors the same way the 100 ohms irritated me as they are symmetrical (almost) so difficult to the which is the 1% ring. I am sure I have mounted some of them the wrong way. I can see that now in the photo if I zoom in and look at the 100 ohm resistors. Hope I can sleep tonight......
The power resistors I have mounted lifted just a little bit from the PCB.
Regarding facing the resistors the same way the 100 ohms irritated me as they are symmetrical (almost) so difficult to the which is the 1% ring. I am sure I have mounted some of them the wrong way. I can see that now in the photo if I zoom in and look at the 100 ohm resistors. Hope I can sleep tonight......
The power resistors I have mounted lifted just a little bit from the PCB.
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Ok I finally got some time to give this F8 a listen. Like your typical DIY enthusiast half of my stuff is broken or work in progress. Swapped out the fried KEF LS50's for my back up speakers and then spent some time getting used to them. Took out the tube I/V section of my Miro Dac and put the AD811 back in. Swapped between the Iron Pre and the Amp Camp Pre. Left Iron Pre in. Verdict - Sounds bloody amazing. I dont have all the fun vocabulary of the Audiophiliac or the Cheap Audio man, lol, but this amp is my favorite over, the F6, M2 and Aleph J. The soundstage is deep, holographic and just pulls you in. Details are everywhere but not fatiguing. Vocals and midrange are clean, precise and the whole amplifier feels more powerful than its 25 watt rating(no kidding). Not entirely sold on the bass section, its fine, but I cant tell if its my speakers or the amp, needs more time and tuning. Asthetically I struggle with its low part count and lack of transformer, lol, how can so few parts sound this way, the PCB is tiny(sorry but its true). Looking forward to hooking this up the XRK Fast/WaW(no idea what that means) ref monitor once I finally complete them.
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just look at them, of course it's speakers....... bass is obviously surplus headphone driver
and that - even Babelfished; Papa's original is no-parts-amp
well, that's intentional; you know how expensive cm of pcbs is today
though, mosfets are apart enough