Because the output stage is not DC coupled, wouldn't it avoid a lot of the problems with offset that the Aleph-X had? Even if the DC operating point of the driver stage is off, the output should be as DC-stable as it would be in single-ended operation.
I've been playing around with something similar, and have found the relative offsets to be much better behaved in the face of even gross asymmetry.
Of course, high absolute offsets in the driver/VAS will still cause problems if you run out of voltage headroom and clip asymmetrically, but that's just another reason to boost the supply rails for the front end.
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|I've made simple solution for Aleph X creeping offset, which is published here :Babelfish XJ , or JX …….. or whatever (Aleph X servo for Greedy Boyz)
as I wrote there, I'm pretty sure that I did saw simmple LTP solution somewhere in Papa's papers, but was never able to find it again ; anyway, from wherever it got originally, it works as intended
regarding this amp, SUSY-fied - I'm pretty sure that OS is DC coupled to FE
even FE neg leg input can be or not DC coupled, as matter of choice - in case of thump being higher than you like and to solve potential issue with higher initial ofset, in case when BFR is chosen in higher value
I've put input cap primarily because I have that issue in prototype and I wasn't sure of behavior once when pcb is made, so I did include cap and jumper; when made on pcb, it shows that majority of issue was Ikebana prototype style induced and now, I can use it with or without jumper, even with my RCA speaks, being microphone-like sensitive and soft
rails higher for FE - I don't care for that ( worthy trick generally) simply because I don't care for squeezing last ounce of rail voltage ........ that's simple matter of choice and approach
Pa named his XA - "25", even if real decent max power is way higher
I can call this one as "like- XA25 amplifier, really having 2 Watts"
Can't wait for them (PCBs). Definitely my next try when available. Can amplifier be bridged and what power can i expect on 8 ohm load?
And thank you for all your efforts.
back'o'napkin fun sez that Ultrasymmetry (fancy name for deliberately and controlled ruined SUSY) is possible; yes, with 2nd dominant, neg phase of same
who needs amp heating your room with 2x 200W, for 2x 160-170W@8R ?
that means serious hardware ....... per channel:
-say 5U/500 Modushop case
-say minimum 600VA Donut of niiice quality; even more if one is fancy welding lower impedance loads (prediction of power at lower loads is better to avoid without actual tests)
-say minimum 120mF per rail, so 240mF
next summer, maybe ....... or this winter, if things are lazy, enough
Bubba Bob started tiling possible names ( after my joke (in our personal correspondence) about Babelfish XA504) then I realized from his list that I didn't even think of possibility of SUSYfying SIT and/or SET iteration
hope nobody will ask for that ....... that would be really over the top
nope
every decent Boy need to learn to say "No", to horde of Lusty Shelahs
Right-Right, as if that's any possibility!
Russellc
Russellc brain: "you should get these boards (even not yet available) as soon as possible." "or, you could wait until next summer or maybe this winter for Super symmetry version." Naughty brain: "Build this as soon as board available, then ALSO build super symmetry to compare." (Sissy-Sit still not completed....) Hopeless.
Russellc
Russellc
human nature ...........
when is hot, we're craving for Winter
when is cold, we're craving for Summer
here, some Winter Breeze, to ease these hot dayz
........ of course that Wabbit is still in Woods, deep ....... but I did some similar things before and everything worked
classical Papalego fun
anyway, in worst case it'll be some greenies and Public Disgrace
when is hot, we're craving for Winter
when is cold, we're craving for Summer
here, some Winter Breeze, to ease these hot dayz
........ of course that Wabbit is still in Woods, deep ....... but I did some similar things before and everything worked
classical Papalego fun
anyway, in worst case it'll be some greenies and Public Disgrace
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human nature ...........
when is hot, we're craving for Winter
when is cold, we're craving for Summer
here, some Winter Breeze, to ease these hot dayz
........ of course that Wabbit is still in Woods, deep ....... but I did some similar things before and everything worked
classical Papalego fun
anyway, in worst case it'll be some greenies and Public Disgrace
That's a very cool breeze..... Time to start saving up for a new chassis.
How about this one?
HSK) HEATSINK1000
1000 watt cast aluminum heatsink. 13-1/2 pounds of aluminum. Back is cast with dividers that could be milled off. Various tapped mounting holes. Shelf worn and some with bent fins or chipped casting. 4-1/4"H x 7-7/8"W x 12". Fin width at base of heatsink measures 1/4" wide.
HSK) HEATSINK1000
1000 watt cast aluminum heatsink. 13-1/2 pounds of aluminum. Back is cast with dividers that could be milled off. Various tapped mounting holes. Shelf worn and some with bent fins or chipped casting. 4-1/4"H x 7-7/8"W x 12". Fin width at base of heatsink measures 1/4" wide.
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looks promising, taking their 1KW claim possible only with forced air - fins distance also indicating that
though, at least from these two pics, base plate looks sorta thin, which measn it's more suited either for few parts having huge interface area ( modules of sort) or plenty smaller parts
no way it's going to eat much heat from not so many parts, having smallish interface area - be it TO247 of puck format (SOT-227-4)
so, no free lunch there ........
going passive with cooling is ...... well, nothing really what some additional Greenies can't solve
problem is not when you (one) want to build one amp, no matter how much parts are going in, while being aware of fact that what is he building is one heluva of amp, costing Plethora of Plethora if bought ready made
problem is when one is on verge to confess his addiction, but ........ not yet
though, at least from these two pics, base plate looks sorta thin, which measn it's more suited either for few parts having huge interface area ( modules of sort) or plenty smaller parts
no way it's going to eat much heat from not so many parts, having smallish interface area - be it TO247 of puck format (SOT-227-4)
so, no free lunch there ........
going passive with cooling is ...... well, nothing really what some additional Greenies can't solve
problem is not when you (one) want to build one amp, no matter how much parts are going in, while being aware of fact that what is he building is one heluva of amp, costing Plethora of Plethora if bought ready made
problem is when one is on verge to confess his addiction, but ........ not yet