there is a safety issue for anyone building this amp....the design is flawed, if the TS can not recognize that, mods are under obligation to stop the member from doing potential harm to himself.....
the bias here is with regards safety.....
the bias here is with regards safety.....
You're goaling at the possible thermal runaway with the biassing applied in the schematic (Q5 temp drift) ?
Analyzing this further, Q5 actually acts as counter to the outputstage TR, provided Q5 is thermally coupled to the OP devices.
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for one the rails are quite high, one misstep and he's a gonner......the voltages are lower that that of tubes, but the potential power discharge is really great....for someone with little experience as shown by his actuations, he would be better off starting with lower voltage low power designs..lot's of those here.......he can then work his way up from there.....
sorry if you feel offended 😱
but you may have misunderstood
the goal was said by poster to be PA, which means general use in public areas
are there not rules and restrictions regarding professional use in public areas 😕
in case of accident, Im not sure the insurance peole will be very nice about it 😡
btw moderators are still allowed to post as 'ordinary' members, which is the case here
From that safety standpoint I wholeheartedly agree; I didn't take the OP
's affinity into account.
I merely responded to the comment about the design itself. From what I've seen it can work reliably if the prerequisites are followed, like thermal coupling I descibed.
you may be right, and why I asked, but got no answer
so I will try again
does this look right 😕
I suggested that maybe the negative of +135V cap should connect to ground, instead of to positive of +130V
might call it a simple drawing error
but build as shown and it explodes like I said
no ?
copyrighted material removed
so I will try again
does this look right 😕
I suggested that maybe the negative of +135V cap should connect to ground, instead of to positive of +130V
might call it a simple drawing error
but build as shown and it explodes like I said
no ?
copyrighted material removed
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No that does not explode. The cap has its + on the 135V rail, the - on the 130V rail. The cap sees 5V in the proper polarity.
Think relative, not absolute. Imagine you're the cap. How much voltage you see between your toes and head?
dirty power 😱😀
joke aside
adding another 6V that way actually works ?
thats interesting
funny that I just had the thought of doing the opposite
connecting primary of a small trafo in series with secondary of a bigger one, to lower voltage
but I thought, better not think about it
I really don't believe the utter nonsense I see in this thread. Of COURSE the amp is dangerous - this is explained in great detail. Some oblique reference to "errors" in the design point to a thread in a Philippines forum that's about something totally different (though there might be something 400 pages deep, I suppose).
No-one seems to have taken the slightest bit of notice of the extensive warnings in the article, nor that fact that I specifically recommend that no-one builds it!
Copyright is out the window (yes, the diagrams are my IP and re-posting is only allowed with written permission - neither asked for nor granted).
It seems probable that not one of those posting about the amp have actually read the article, gathered the actual intent behind it, or read the explanatory text and WARNINGS that are scattered in numbers throughout the article.
Personally, I'm really annoyed at the nonsense that's being sprouted here. Read the article ... ALL OF IT !! ... then at least you may know a little more than you do at present.
No-one seems to have taken the slightest bit of notice of the extensive warnings in the article, nor that fact that I specifically recommend that no-one builds it!
Copyright is out the window (yes, the diagrams are my IP and re-posting is only allowed with written permission - neither asked for nor granted).
It seems probable that not one of those posting about the amp have actually read the article, gathered the actual intent behind it, or read the explanatory text and WARNINGS that are scattered in numbers throughout the article.
Personally, I'm really annoyed at the nonsense that's being sprouted here. Read the article ... ALL OF IT !! ... then at least you may know a little more than you do at present.
Dear Rod,
Are you including me in your speech? I can not gather that from your response. I'd like to tell you that I frequented your site a quite a lot and perused it from back to front, left to right, though I can't remember details about this amp. But I know about you and your rich use of warnings, safety above all.
Stacked supply rails, I use it too.
P.S. Maybe you remember the guy with the digitally controlled pre-amp a whole number of years ago, on your forums =)
Are you including me in your speech? I can not gather that from your response. I'd like to tell you that I frequented your site a quite a lot and perused it from back to front, left to right, though I can't remember details about this amp. But I know about you and your rich use of warnings, safety above all.
Stacked supply rails, I use it too.
P.S. Maybe you remember the guy with the digitally controlled pre-amp a whole number of years ago, on your forums =)
Yes, that works. Well, putting in 'series' secondaries;keeping primaries parallel ofcourse. Rectify and stack the outputs. the 130V rail is a big supply, the 135 is the voltage level, but it actually is a stacked 5V supply that dances along on the 130V rail. It's to reduce dissipation and still feed the drive requiring a bit higher voltage. You can imagine a rectified galvanically separated power source to be a battery, and like batteries, you can stack them.
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No, you're not included. You appear to have been the solitary voice of reason in what appears to be a "discussion", but is more of an uninformed ramble (rant) by people who haven't read the article, but think they must know what it's all about, because ... um, ahhh, hmm ...
No, I don't know the answer, but it's one of the reasons that I visit this forum so very rarely.
I don't see a problem. The cap has 5 volts across it. It will work fine.
I must admit to not noticing the logo on the schematic and so not knowing there was an article to read. Now I see the purpose of this amp so my comments about practical issues are moot. It is not intended to be built.
I think I will design a 5KW tube amp, post the schematic someplace where Google can find it. Then post "reviews" on some audio sites then wait and see what happens. I better get busy drawing as it needs to be ready by April.
Hi ChrisA
greetings http://www.diyaudio.com/forums/solid-state/1813-kilowatt-nice-500w-schematic-you-3.html#post3107900
somebody already posted it before april
warm regards
andrew lebon
greetings http://www.diyaudio.com/forums/solid-state/1813-kilowatt-nice-500w-schematic-you-3.html#post3107900
somebody already posted it before april
warm regards
andrew lebon
oh, I have read it, multiple times
your red warning signs are flashing before my eyes
I remember one especially, just one flash, and you are ash
😀but as said, why not use lower voltage, and instead bridge two channels
PA is balanced anyway
Looks like the link to the 5KW amp is gone. Just a survey scam there now but I was talking about a 5KW vacuum tube amp.
RodE,
i visit your web page every now and then, lot's of good stuff there, i link many of your posts in other forums....
you are one of the good guys in my book....
people will take you seriously no matter how you say " just one flash, and you are ash"....and your humorous 1.5kw amp is one such example, i can see the humour in it but a lot of other folks don't, they think that they ought to build the amp cause of its sheer power....
yosha is one of those, probably a teener on his first year of building amps or a freshman in a trade school....and many others......
like moths who are attracted to the lamp even if they will get burned....these moths dive in anyway....
you provided the "lamp"......
now we are hard at work trying to prevent them getting burned....
so if you were a mod, how would you have handled it? i am sure mods here would like to know...
i have worked with Aussies, Irishmen, Brits and Yanks in overseas projects in the Oil and Gas Refining industry......i am used to the F-word they regularly dished out.....but it was my Aussie friend who always reminded me, "do not take it to heart...."
finally let me welcome you to the forum.....here, safety is paramount....
What is the advantage of running the frontend and drive at ~5V above that of the OPS ? Is there enough gain in power to be worthwhile or is it simply a efficiency thing ?
improved clipping performance, when the output stage clips, the VAS does not...many Japanese commercial amps used this scheme...
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