Some friends told me the circuits they publish has errors
something made with the intention to hide secrets.
I am not sure they do that..... in my mind this is inconceivable.... i just cannot accept this can be possible...too much disonest.
To manipulate numbers, based in strange calculations or "modern" ways to measure...this is only to work with people's ignorance to sell some magic.. some bad use of marketing...not correct but less terrible than to publish wrong schematic...i have some resistance to believe my people is doing that....not because Brazilians are saints..in the reality we are much more the opposite, but the local audio community, discovering dirty tricks that way, will feel offended, and as a consequence, will work to burn the brand name..and for sure no one will buy...so.... doing that (if they do) they will have short life.
First problem with them is the price..... 6000 dollares, for Brazil standards, is a very high price if you analise what you are buying..what you have inside...the part's value...there's anything golden or special inside..cheap fans..cheap heatsinks..cheap transistors, normal parts..not big condensers, not big transformer..a single transformer..... an economic amplifier that should be sold for 1500 USD....this, because the average price you have in the competition with the same (real) output power.
regards,
Carlos
something made with the intention to hide secrets.
I am not sure they do that..... in my mind this is inconceivable.... i just cannot accept this can be possible...too much disonest.
To manipulate numbers, based in strange calculations or "modern" ways to measure...this is only to work with people's ignorance to sell some magic.. some bad use of marketing...not correct but less terrible than to publish wrong schematic...i have some resistance to believe my people is doing that....not because Brazilians are saints..in the reality we are much more the opposite, but the local audio community, discovering dirty tricks that way, will feel offended, and as a consequence, will work to burn the brand name..and for sure no one will buy...so.... doing that (if they do) they will have short life.
First problem with them is the price..... 6000 dollares, for Brazil standards, is a very high price if you analise what you are buying..what you have inside...the part's value...there's anything golden or special inside..cheap fans..cheap heatsinks..cheap transistors, normal parts..not big condensers, not big transformer..a single transformer..... an economic amplifier that should be sold for 1500 USD....this, because the average price you have in the competition with the same (real) output power.
regards,
Carlos
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I found a video in youtube, and the guy said has measured
77 volts RMS, 1 Kilohertz, 2 ohms resistive load.... watch the youtube video below the text.
But they have not shown the load and the generator...can be a burst tone generator..also have not explained if measured using VTVM or Scope... in the image you see the scope and the multimeter...seems to be a Fluke one.
I have opened the thread asking for theoreticall folks help...but as you see...no one came to explain things in details...only you folks sumaudioguy, DJK and 18tbx46..... they use to be in my threads, dissecating my amplifiers and pointing errors...when we need them to help, they do not came to help.
I would like to ask, clearly, if between you exists the needed knowledge i do not have, to analise the circuit and answer me a simple and direct question:
Can this circuit, put out 77 RMS volts, over 2 ohms, 1 Kilohertz entering..continuous power, unclipped, sinus entering and for more than a few miliseconds?
http://www.youtube.com/watch?v=32SAGHYyNx4&NR=1
regards,
Carlos
77 volts RMS, 1 Kilohertz, 2 ohms resistive load.... watch the youtube video below the text.
But they have not shown the load and the generator...can be a burst tone generator..also have not explained if measured using VTVM or Scope... in the image you see the scope and the multimeter...seems to be a Fluke one.
I have opened the thread asking for theoreticall folks help...but as you see...no one came to explain things in details...only you folks sumaudioguy, DJK and 18tbx46..... they use to be in my threads, dissecating my amplifiers and pointing errors...when we need them to help, they do not came to help.
I would like to ask, clearly, if between you exists the needed knowledge i do not have, to analise the circuit and answer me a simple and direct question:
Can this circuit, put out 77 RMS volts, over 2 ohms, 1 Kilohertz entering..continuous power, unclipped, sinus entering and for more than a few miliseconds?
http://www.youtube.com/watch?v=32SAGHYyNx4&NR=1
regards,
Carlos
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Previous post.... dissecating is wrong...the word is dissecting
Sorry.....my english...... it is poor.
regards,
Carlos
Sorry.....my english...... it is poor.
regards,
Carlos
What amp is it really?
I watched the video and thought the signal was burst for just one or two cycles because of unstable trace. The power supply shown could not possibly support that output for long therefore I assume the duty cycle of the burst is less than 10%. The circuit of post 1-5 has parts to deliver enough current to do this if it works. RMS usually means continuous power and from this amplifier that is impossible. ALSO...I see the clipping shown if quite a bit of clipping. The schematic of post #2 shows the high voltage rail at +92 volts which means clipping could not possibly be above that voltage. 92 volts multiplied by .7 = RMS volts available which is like 64 volts RMS maximum. So that is 500 watts into 8 ohms. With losses and so on probably like really 400-450 into 8 ohms. This amp is very similar to the Crown CPX series which blow up all the time for no reason. I believe this amp would also fail for no apparent reason other than class H. Given the size of the transformer and the lack of a high power switching supply.... the transformer looks a lot like this size, Parts-Express.com:Avel Y236857 625VA 45V+45V Toroidal Transformer | TRS transformers transformer toroidal transformer toroidal toroid mounting kits kit gauge copper avel 4 gauge , which is 625 watts worth. Even with a generous increase the transformer could not be more than 800 watts or so. For music that means about 800 watts total out peak so this takes us back to the 400 watts into 8 ohms amplifier. 77 volts out (RMS) requires supply voltage of at least plus and minus 110 volts.
Let us rename it the "Happy Thoughts" amplifier.
I watched the video and thought the signal was burst for just one or two cycles because of unstable trace. The power supply shown could not possibly support that output for long therefore I assume the duty cycle of the burst is less than 10%. The circuit of post 1-5 has parts to deliver enough current to do this if it works. RMS usually means continuous power and from this amplifier that is impossible. ALSO...I see the clipping shown if quite a bit of clipping. The schematic of post #2 shows the high voltage rail at +92 volts which means clipping could not possibly be above that voltage. 92 volts multiplied by .7 = RMS volts available which is like 64 volts RMS maximum. So that is 500 watts into 8 ohms. With losses and so on probably like really 400-450 into 8 ohms. This amp is very similar to the Crown CPX series which blow up all the time for no reason. I believe this amp would also fail for no apparent reason other than class H. Given the size of the transformer and the lack of a high power switching supply.... the transformer looks a lot like this size, Parts-Express.com:Avel Y236857 625VA 45V+45V Toroidal Transformer | TRS transformers transformer toroidal transformer toroidal toroid mounting kits kit gauge copper avel 4 gauge , which is 625 watts worth. Even with a generous increase the transformer could not be more than 800 watts or so. For music that means about 800 watts total out peak so this takes us back to the 400 watts into 8 ohms amplifier. 77 volts out (RMS) requires supply voltage of at least plus and minus 110 volts.
Let us rename it the "Happy Thoughts" amplifier.
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Yes Sumaudioguy... this is exactly what i am thinking about
not with your precision but this was the output power was in my imagination, evaluating looking to the transformer size and watching the power supply filters.
Their reference, their competition, to create this amplifier was exactly the Crown... i could read an interview, they said this amplifier can work with 1.5 ohms when Crown cannot (if i understood correctly what the guy said).
Supply seems normal, common and standard... i could not see that "X" supply they use to talk about... a dual voltage supply...just that... the input voltage enters in a non standard way.... two phases...industrial style...professional style with circuit breakers... the primary has not continuity with the secondary as people said (some folks told me that...here, in Brazil), and no autotransformer was used.... AC power conditioning not used and no switching power supply...so..the rules, to generic, old style, traditional supplies, are these ones we both know and you explained very well.
Thank you very much Sumaudioguy.
regards,
Carlos
not with your precision but this was the output power was in my imagination, evaluating looking to the transformer size and watching the power supply filters.
Their reference, their competition, to create this amplifier was exactly the Crown... i could read an interview, they said this amplifier can work with 1.5 ohms when Crown cannot (if i understood correctly what the guy said).
Supply seems normal, common and standard... i could not see that "X" supply they use to talk about... a dual voltage supply...just that... the input voltage enters in a non standard way.... two phases...industrial style...professional style with circuit breakers... the primary has not continuity with the secondary as people said (some folks told me that...here, in Brazil), and no autotransformer was used.... AC power conditioning not used and no switching power supply...so..the rules, to generic, old style, traditional supplies, are these ones we both know and you explained very well.
Thank you very much Sumaudioguy.
regards,
Carlos
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