Has any one built this 1KW amp?

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Please see, the smaller torrid primary is 40 amps x 240 volts = around 9.6 kw,and other one 60 amps. x 240 volts =14.40 kw. not 5 Kw. and I want to use them for 4 chanalles of amp on each traffo. And I will do that in near future, smaller one for 1.8 kw. class ab x 4 chanalles . and bigger one 2.5 kw x 4 channeles in class AB only.
 

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I would definitely do a 100%-50%-0-50%-100% secondary winding and a class G output stage.

10 pair of MJ15024/25 will have a beta of 15 at 80A require about 5A of drive current, and about 250mA from the pre-driver (a triple output circuit). 80A peak would be 56.6A RMS, or about 3.2KW at 1Ω.

The TO-66 250V/2A 30Mhz 40W SOA at 100V pre-driver I used is no longer available. I would probably use something like the 2SA1943/2SC5200, although rated at 40W SOA at 100V it will not be as robust due to its 150°C junction temperature rating vs the 200°C rating on the TO-66 part. If you could get the ON Semiconductor MJL/MJW 1302/3281 that would be even better with their 100W SOA at 100V they would be adequate.

The top rail would be a duplicate of the bottom rail with a 6V level shift, so you would end up with roughly the same number of output devices you originally planned for, but much better reliability. This would essentially be the Crest 10004 output stage with your supply being much stiffer.
 
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Yes Sir this is a leach amplifier modified.no P.c.b. is used in output section. Rail wires are 2.5 m.m. thick.Today I run this amp for 6 hours non stop with 8nos. 15' speakers+8 nos.12" speakers +8 nos. Tweaters Total d.c resistance .5 ohm upto 52 volt and 33 amps on output. Crispy crystal clear highs lively mid and deep low was what I got . I am happy with result.Sugestion to make this was by Capsighter Chinoko .sending some more photos.Paa ji Aap ko main aap ki id par message bhejunga.

hi vedmitraa,
can u share this amp pcb layouts.
 
my 1400 watts per channel class Ab amp

well it is actually a modified version of super leach 700 watts with 16 pairs of 5200 , 1943 in output and one pair as driver,p.c.b. section only used upto predriver as yu can see in photos.Power really more than 1400 watts crispy h.f., melodious mids,and thumping bass, have now tested even with 6 nos. 18" speakers parallel for more than 4 hours.
 

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well it is actually a modified version of super leach 700 watts with 16 pairs of 5200 , 1943 in output and one pair as driver,p.c.b. section only used upto predriver as yu can see in photos.Power really more than 1400 watts crispy h.f., melodious mids,and thumping bass, have now tested even with 6 nos. 18" speakers parallel for more than 4 hours.

thank you very much vedmitraa, would you share the schematic?
 
well it is actually a modified version of super leach 700 watts with 16 pairs of 5200 , 1943 in output and one pair as driver,p.c.b. section only used upto predriver as yu can see in photos.Power really more than 1400 watts crispy h.f., melodious mids,and thumping bass, have now tested even with 6 nos. 18" speakers parallel for more than 4 hours.

That's not a 'Super Leach' - it's just the standard Leach circuit with a few(?) extra output transistors. The real 'Super Leach' uses the cascode output stage which you could run off these supply voltages all day long - if you can get the heat out - with no question as to the long term reliability. If you're open to experimentation you might want to give it a try before blowing up banks of 14 C5200's. A 7x2 arrangement really is more reliable if you go over over 90V rails. It's also pretty easy to convert the S-Leach (later) to a class G by adding some additional support circuitry. Two 30A ultrafast rectifiers, a zener and bootstrap capacitor, and an RC snubber on each bank (it really is that simple).
 
I'm suggesting you adapt the Crest schematic, it's essentially the Leach.

The basic Leach has a class AB output stage. The Super Leach has a series connected output stage to reduce the high voltage SOA demands, a bit like a cascode but the drive voltage tracks at half the required output voltage.

The Crest is like the class AB Leach with the series connected outputs of the Super Leach. When it runs close to the low volt rail the level shift zener then cascodes the series connected outputs rather than trying to do a half voltage thing. This is class G.

The Super Leach does a series connected Vas stage that also tracks the half voltage like the outputs. I would not do this, just do it like the Crest, or do a fixed cascode with an LED reference is you want to.

I assume you have the Super Leach schematics?

(they were just for reference only to compare the topology with the Crest)
 
Thanks Mr. DJK,
While searching I found all the files of Super leach in my computer including P.C.B. when Leach is giving me so good results I think super leach will do wonders with voltage divided, I will give it a try and I think this will be a hit like Leach, thanks for the Crest file also.
warm regards
 
Relays for soft start of my 60 amp. 240 v. primary torrid

Thanks, for the advice,
mean while I have got some relays for the soft start circuit to be used with my 60 Amps. 240 Volts primary torrid and 40 Amps 240 volt primary torrid photos of which I have posted earlier. These relays coil 24 volts D.C. 4pair 30 Amps. silver and Silver carbon contacts each, please post a suitable soft start circuit if any body have
 

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DISTORTION

Hello Workhorse Sir
i assembled your drive its working but at low volume sound
is distorted i tested drive on 1 pair 2sc5200 at 8 ohms load on 70 volts dc +/-
will distortion go if i add more pairs
warm regards
sameerx1:confused:
but what remains silly is the distortion at low volume even Kimberlator experienced this distortion
 
Hello Workhorse Sir
i assembled your drive its working but at low volume sound
is distorted i tested drive on 1 pair 2sc5200 at 8 ohms load on 70 volts dc +/-
will distortion go if i add more pairs
warm regards
sameerx1:confused:
but what remains silly is the distortion at low volume even Kimberlator experienced this distortion

To enhance the low level signal clarity, put one more diode connected transistor in series with other two already in the schematic and set the trimmer accordingly to get 20mA idle current in output devices.
 
ULTRA-CLEAN

Friends here I present A design Named by me "ULTRA- CLEAN". this is around 1KW at 2 ohm's load with distortion down to "0.001%".for real hi-fi lovers and with a slight change around 2 kW. on 1ohm load at 0.002% distortion and, on 2 ohm more than 48 volts at out with 0.002% distortion and around 1116 watts
 

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