I presume that this circuit is actually working
contrary to Rod's design that its only simulated and not
actually put to life
I do not know if this circuit does suffer or does suffer
from instabilities which is very important, specially
with the specified power supply.
what are you views on this...
(link removed by moderators for safety reasons)
contrary to Rod's design that its only simulated and not
actually put to life
I do not know if this circuit does suffer or does suffer
from instabilities which is very important, specially
with the specified power supply.
what are you views on this...
(link removed by moderators for safety reasons)
its power feels very convincing
but of course very
dangerous
since there are no good isolation..........
ok here
let us assume that we have a good and perfect power
supply unit with robust amount of filtering ( caps ) and
and still with plus/minus 130V on its rails, will this thing
still works?
or are we still facing instabilities,
since there are no lag compensation
capacitors
but of course very
dangerous since there are no good isolation..........
ok here
let us assume that we have a good and perfect power
supply unit with robust amount of filtering ( caps ) and
and still with plus/minus 130V on its rails, will this thing
still works?
or are we still facing instabilities,since there are no lag compensation
capacitors
wouldnt the Vceo of the recommended outputs be exceeded? I certainly think the SOA would be...
not to mention, how the hell would you cool the output stage?
nope. no way is this going to work.. and for such output power you certainly wouldnt want Class AB anyway. Class D would make a hell of a lot more sense.
not to mention... if anyone touches speaker terminals while grounded - zap, dead!
not to mention, how the hell would you cool the output stage?
nope. no way is this going to work.. and for such output power you certainly wouldnt want Class AB anyway. Class D would make a hell of a lot more sense.
not to mention... if anyone touches speaker terminals while grounded - zap, dead!
So is this a double insulated build or ....
Anyway, probably many questions to consider but here's just one;
1. What potential is the non-isolated ground at? and what would happen if chassis to chassis contact were made with something else? Then what would happen if one of the 30 amp fuses blew?
I that two questions?
Cheers
Anyway, probably many questions to consider but here's just one;
1. What potential is the non-isolated ground at? and what would happen if chassis to chassis contact were made with something else? Then what would happen if one of the 30 amp fuses blew?
I that two questions?
Cheers
It's safer than that switching amp that a US electronics magazine published which ran directly off the line (no isolation transformers at all).
As for this amp... I don't see any feedback from the emitter resistors to provide current limiting or SOA protection. And there's no protection circuits to disconnect the speaker or crowbar the power supply in case of a DC fault. Any speaker that will handle 5000 watts is worth protecting, even if it's rented.
It doesn't make me regret buying a Yorkville Audiopro AP4040 which does 2400 watts RMS bridged into 8 ohms.
As for this amp... I don't see any feedback from the emitter resistors to provide current limiting or SOA protection. And there's no protection circuits to disconnect the speaker or crowbar the power supply in case of a DC fault. Any speaker that will handle 5000 watts is worth protecting, even if it's rented.
It doesn't make me regret buying a Yorkville Audiopro AP4040 which does 2400 watts RMS bridged into 8 ohms.
hienrich said:its power feels very convincing
but of course very
since there are no good isolation..........
ok here
let us assume that we have a good and perfect power
supply unit with robust amount of filtering ( caps ) and
and still with plus/minus 130V on its rails, will this thing
still works?
since there are no lag compensation
capacitors
It is irresponible to guess if the amp is going to be stable or not just from schematic, but feedback definitely is not very high, so maybe...
I'd leave it for other reasons above.
"It's safer than that switching amp that a US electronics magazine published which ran directly off the line "
Are you referring to the one that was in the April issue?
A bit of an April fool's joke there. One tip-off should have been when he had the constructor cutting out lids from tin cans to make heatsinks for the zener diodes (I thought that was really funny), and the lack of a filter on the output of the amp (so your tweeters would go up in flames).
This current disaster is not worth discussing either.
If you really need a 5KW amp, just download the schematic for a Crown VZ5000. It only needs eight pair of MJ21193/94 per channel.
Are you referring to the one that was in the April issue?
A bit of an April fool's joke there. One tip-off should have been when he had the constructor cutting out lids from tin cans to make heatsinks for the zener diodes (I thought that was really funny), and the lack of a filter on the output of the amp (so your tweeters would go up in flames).
This current disaster is not worth discussing either.
If you really need a 5KW amp, just download the schematic for a Crown VZ5000. It only needs eight pair of MJ21193/94 per channel.
hienrich said:I presume that this circuit is actually working
contrary to Rod's design that its only simulated and not
actually put to life
I do not know if this circuit does suffer or does suffer
from instabilities which is very important, specially
with the specified power supply.
what are you views on this...
jajajajajajajaja
I found the magazine... you're right, it was an April issue: Popular Electronics, April 1996. It's on the cover, so I doubt it was an intentional April Fools joke by the editors. "Build a Switching Amplifier - An easy-to-build, low-cost, 60-watt stereo amp that delivers really great sound" The author is Rolando R. Burbon.
And, yes, theres's no output inductors, no negative feed-back, and no performance specifications at all. But there are PC board layouts and photos of the completed amp in a decent DIY case which sure make it look like a legitimate project.
If my scrap-paper analysis of the non-isolated power supply is correct, the signal common of the amp will be hot, swinging from +26 to - 134 volts. There's a warning against touching the boards while the amp is powered up, but nothing about how the input and outputs are also hot.
If this was an intentional prank, someone must have had a grudge against the magazine and was hoping for lawsuits. If not, well, both the Popular Electronics staff and the author must be dumber than squirrels.
And, yes, theres's no output inductors, no negative feed-back, and no performance specifications at all. But there are PC board layouts and photos of the completed amp in a decent DIY case which sure make it look like a legitimate project.
If my scrap-paper analysis of the non-isolated power supply is correct, the signal common of the amp will be hot, swinging from +26 to - 134 volts. There's a warning against touching the boards while the amp is powered up, but nothing about how the input and outputs are also hot.
If this was an intentional prank, someone must have had a grudge against the magazine and was hoping for lawsuits. If not, well, both the Popular Electronics staff and the author must be dumber than squirrels.
jaycee said:
yep. at 4ohm loads, it would be fine and it would do about 1900watts with 10pairs MJL devices but need about 16 pairs of the toshiba devices.
at 2 ohms, it will do (at most, but probably less) 3700watts but needs 21pairs of MJL or 32pairs toshiba devices.
with things like these, I would think buying a high powered pro amp is cheaper and much much safer! it does take away the fun and DIY though.
At these power levels class B or AB are not practical. Class G, H (preferably 3 tier) or D should be employed instead. The topic of high voltage amplifiers and mains isolation has been already discussed many times, and there are a lot of related (closed) threads that should be easy to find with the help of the search engine.
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