Do the two sides need to be wired together,
clarify
and what if any value of resistor be used for power supply bleed off
I'm not using bleeders in my amps at all; they can save you if you're testing Cap Banks prior to wiring to amp pcbs but - I'm never doing that and even if I'm in situation of messing around (as with my T-Bed), I'm not forgetting to blast them with dummy load leads
feel free to use/mount them, improvise how; 10mA through bleeder is good enough so - 3K3 , dissipation is 10mA^2*35V; take at least twice more for declared resistor power
on First Watt clones I usually do this through a CL 60..
there is a footprint for 10-12mm Dia NTC on Cap Bank pcb itself -- why not using that, if I already put it there
if you really want Kosher - take adequate wire from output GND on Cap Bank pcb to [KBPC bridge +capacitor+resistor] ground-lift-thingie
there is a footprint for 10-12mm Dia NTC on Cap Bank pcb itself -- why not using that, if I already put it there
Exactly why I asked. knowing these were for multiple projects, I didnt know if that was for my intended purpose or something else. So CL 60 on board, ground wire from "G" to chassis. Or is some other size NTC used? I have a bunch of CL 60...
Exactly why I asked. knowing these were for multiple projects, I didnt know if that was for my intended purpose or something else. So CL 60 on board, ground wire from "G" to chassis. Or is some other size NTC used? I have a bunch of CL 60...
On a number of PS boards on bottom grounds were tied together, just wondering here...
all you can and need to see
both schm and pcb pics - left side input from bridges, right side output to amp pcb
Attachments
Powered on for the first time today - everything stable, offset a few mVs. Increased Iq to about 1.54A (0.170V/.11) on both channels, after 10-20 minutes of cooking the amp is blowing 1.25A/250V fuse (one for both donuts). Just ordered bigger fuses...
So, the Macho 252 SIT is behaving and sounding really good. Seems like the 8V diodes took care of the issues.
Besides the somewhat mismatch with my high gain preamp ( it puts out 20Vrms ) I'm noticing some interesting behavior.
The treble is a lot more prominent than with the F4/Sissy ( all amps driven with the same preamp ). I can hear my DAC settle down as it warms up, perhaps those Burson v6 Classic OP Amps need to warm up... ( note to self, I got the Burson v6 Vivids in the P3... ).
The sound is also much more clear. Meaning the voices and instruments come out of a "darker" background.
Likely this is due to a lower noise floor?
I figure in a couple of months or so I'll be able to try it with an Iron Pro balanced.
Long term, I figure 38 wpc ( a little more into 6 ohms, huh?) ) just won't make this as a headbanging amp, unless you got something like 100 db/w Zu's. With my 90db/w they sound very good, oddly, as I've noticed, they don't sound loud, except, I can't hear the phone ring or my wife ask me to do something. I suppose that is all good then. ;-)
I do need to wire up the system to add the Entec woofers and then check the integration. It worked very well with the Sissy and F4 (indeed with everything) so I don't expect any untoward behavior.
Great amp... now Big Badda Bing.... if I can only get 200 wpc into 4 ohms with SITs... I might be able to clean up the racks. Just make it so the gain is adjustable... 12 or 24 db... so those of us with high gain tube preamps won't run into excessive noise.
Besides the somewhat mismatch with my high gain preamp ( it puts out 20Vrms ) I'm noticing some interesting behavior.
The treble is a lot more prominent than with the F4/Sissy ( all amps driven with the same preamp ). I can hear my DAC settle down as it warms up, perhaps those Burson v6 Classic OP Amps need to warm up... ( note to self, I got the Burson v6 Vivids in the P3... ).
The sound is also much more clear. Meaning the voices and instruments come out of a "darker" background.
Likely this is due to a lower noise floor?
I figure in a couple of months or so I'll be able to try it with an Iron Pro balanced.
Long term, I figure 38 wpc ( a little more into 6 ohms, huh?) ) just won't make this as a headbanging amp, unless you got something like 100 db/w Zu's. With my 90db/w they sound very good, oddly, as I've noticed, they don't sound loud, except, I can't hear the phone ring or my wife ask me to do something. I suppose that is all good then. ;-)
I do need to wire up the system to add the Entec woofers and then check the integration. It worked very well with the Sissy and F4 (indeed with everything) so I don't expect any untoward behavior.
Great amp... now Big Badda Bing.... if I can only get 200 wpc into 4 ohms with SITs... I might be able to clean up the racks. Just make it so the gain is adjustable... 12 or 24 db... so those of us with high gain tube preamps won't run into excessive noise.
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Well, I can include Coffee maker, grinder, and also mid size robot vacuum cleaner in BigBadaBoom amp schematic
I can't care less for Greedy Boyz having high gain preamps, when thinking of amp with regular gain .........
I can make in a day power follower 200W+ amp schematic, but then you guys are not going to have preamp potent enough to drive it .... especially taking in account fact that majority of high swing preamps are not balanced
so, 100 Greedy Boyz, 101 pairs of tits ......... even Mighty ZM isn't capable of grooming all of these
I can't care less for Greedy Boyz having high gain preamps, when thinking of amp with regular gain .........
I can make in a day power follower 200W+ amp schematic, but then you guys are not going to have preamp potent enough to drive it .... especially taking in account fact that majority of high swing preamps are not balanced
so, 100 Greedy Boyz, 101 pairs of tits ......... even Mighty ZM isn't capable of grooming all of these
each power supply having its own ground,
connected to chassis through NTC or whatever you make instead (NTC+bridge+cap)
Wondering who has two pairs...so, 100 Greedy Boyz, 101 pairs of tits…..
Yes please!!
Ok, with a bigger fuse cooking continues...
My latest measures: Iq increased to about 1.64A, offset below +/-1mV, rails +/-37V, heatsinks near big MOSFETs are about 50-55 deg. C, small heatsinks for Q1/Q2 (BD139/BD140) are quite hot as well, about 50 deg. C. Ambient temp about 18-19 deg. C.
My latest measures: Iq increased to about 1.64A, offset below +/-1mV, rails +/-37V, heatsinks near big MOSFETs are about 50-55 deg. C, small heatsinks for Q1/Q2 (BD139/BD140) are quite hot as well, about 50 deg. C. Ambient temp about 18-19 deg. C.
Neat, clean and well organized as always qwertyl.Thanks. I will take more photos soon...
Best,
Anand.
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