1000W Simple PA Amplifier

10k must be hot (1.5W disipation), you can use 5W resistor.
thanks for suggestions sir... :)
can we add class h stepper?
and how max volt supply if we add class h stepper?

thanks regar
 

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It's possible to add class H steper and use +/-60V, +/-120V...
Can you post some pictures and what about sound ?
Regards
NAD used this at their models 2400 and 2600. For 6db more undistorted output power too much effort - so I think.


sir... R10k very hot to burn at the time played only a few minutes.
2volt bias b to b, and 90vdc supply.
i need your suggestions ? View attachment 351294
By a lot of commercial amp devices this resistors are the main reason for burned PCBs, even by such brands like Krell and Mark Levinson.
By closed chassis cover the max temperatur at the resistor should be not more than 25 degrees (better 20 degrees) about ambient.
This means resistores like follow:
http://cfnewsads.thomasnet.com/images/large/015/15067.jpg (for heatsink mount) or
http://img.directindustry.de/images_di/photo-m2/max-250-k-x003a9-5-250-w-001-1-mal-13783-3434033.jpg
http://hifibau.de/product_info.php/info/p15_Leistungs-Widerstand-50-Watt.html
Another solution is the use of 8 or 10 smaller devices in serial mode.
I want keep it simple.
By the use of a TO126 outlined Transistor there is the possibility of chassis mounting (base connected to GND). Nevertheless those approach is simple, too.
Circuits from Stan Curtis used this approach e. g. Monrio MC25, Moth 30W and Mission Cyrus ONE - go to
A Paul Kemble web page - Mission Cyrus 1 integrated amplifier.
 
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Why do you don't cascode LTP input?!
MPSA92 have low gain, low Ft. Cascoded them with small signal devices like BC560C to get more better result.

And add an active CCS.

I was considering cascode LTP with zeners but I want to keep it simple, and 2SA970 can be use for LTP or some better transistors. SR50 use cascode ... and this amp is not popular at all. I don't want to build this amplifier it's only for people who want to diy it for fun.
 

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Apex,
I suggest you consider the audience you have attracted.
The vast majority looking at your designs are only there because you publish high power designs. These same Power hungry Members in general do not understand what makes a good amplifier and what makes a bad amplifier. All they want is silly power ratings.
 
Why do you don't cascode LTP input?!
MPSA92 have low gain, low Ft. Cascoded them with small signal devices like BC560C to get more better result.

And add an active CCS.
the BC560 can also used by nearly direct replace. To reduce the voltage (Vce Voltage) only two additional resistors must be introduce in the collector lines. As an additional wanted effect occurs a lower thermal value above ambient (less power loss) even by enhance the idle current through the input differencial amp (3-5mA is a better value for good sound than only 1,3mA - the currently value).
This I have often realized by several high voltage audio power amps like NAD to avoid burned PCB areas arround the input stage with TO92 small signal transistors.
 
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Apex,
I suggest you consider the audience you have attracted.
The vast majority looking at your designs are only there because you publish high power designs. These same Power hungry Members in general do not understand what makes a good amplifier and what makes a bad amplifier. All they want is silly power ratings.




http://www.diyaudio.com/forums/soli...ur-solid-state-pics-here-179.html#post2547057
APEX NX16 proba u ku?i/testing in the house AVI - YouTube


http://www.diyaudio.com/forums/soli...ur-solid-state-pics-here-179.html#post2547057


http://www.diyaudio.com/forums/soli...ur-solid-state-pics-here-223.html#post2877556
APEX F100 by 44250 (with smps power supply) - YouTube

http://www.diyaudio.com/forums/soli...imate-fidelity-amplifier-116.html#post2885214
APEX AX12 u 44250 izvedbi/done by 44250 strano - YouTube

http://www.diyaudio.com/forums/solid-state/164093-100w-ultimate-fidelity-amplifier.html#post2135804
Apex AX-11 - YouTube
Apex AX11 on Http://forum.diyaudioproject.eu - YouTube

http://www.diyaudio.com/forums/solid-state/173462-studio-reference-amplifier.html#post2300775
Apex SR200 on http://forum.Diyaudioproject.eu - YouTube

http://www.diyaudio.com/forums/solid-state/236256-retro-amp-50w-single-supply.html#post3497279

all that on one (HiFi) side and BA1200,B500 and H900 on the other (PA) side,now you could reconsider your conclusion! all other versions of HiFi amplifiers were product of someone else´s wishes for more power. APEX knows very well what is high power amplifier and what is HiFi amplifier,he proved it so many times so i don´t see what is the problem here? all i can see from you is obstrtucting mr. APEX ,unnecessarily and unjustifiable discouraging other members to build his designes. i can say that because i personaly have quite a few his amplifiers,and also personaly know so much people that just love to listen his amplifiers of all kinds.

if you are bothered by type of people that APEX attracts here,please help yourself by sharing some of your designes that are more HiFi than those with APEX logo and i am sure that people will appreacheate and follow you and your work.

what APEX said ever to ostripper,or Nelson Pass,or anyone else for sharing their designes? on the other side - what ever said ostripper,Nelson Pass or anyone of reckognised designers to mr.APEX? NOTHING because they are not bothered each with other,they are looking their bussiness and their designes,trying to improve themselves and their designes,minding their own bussiness,keeping their nose where it should be.

try to share some designes instead suggestions like previous one...
 
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Apex,
I suggest you consider the audience you have attracted.
The vast majority looking at your designs are only there because you publish high power designs. These same Power hungry Members in general do not understand what makes a good amplifier and what makes a bad amplifier. All they want is silly power ratings.

I know that but I can't change what they want, there is many bad designs on the net, and there is many comercial brand amplifier similar to BA1200. This amplifier is simple and work, it is good enough for diy.