SlewMaster Builds

yes the fans i hate on a amp in my attic built listening room thats dead silent. my pc i use for flac and dsd has been worked on with a 6" fan on a speed control to slow to a silent level. i was hoping to use another zallman set up like this on the amps.
the p101 are running now when i am here online for 4 to 5 hours a night when i can and they don't even get warm only in summer heat. these have no fan at all. that is how little power i use.
i have a adcom gfa 5400 modded and rebiased it as well as the p101 played at low levels sound cramped. open them up and the sound open.
this is the thing i'm after no compression at low volume.
when the 2 slews are done i plan on selling both the adcom and the 2 p101
 
guys the last few days i have been looking for a soft start system for the 2 slew's and this has got me confused .
i see some are operated by a 12v source, so i would guess that another transformer is needed. on the new chassis i want to add a round push on and off led blue switch.
led needs 12 v to light so is the switch turning the soft start on which in turn switches on the main power?
i'm thinking it works kinda like a relay, low power to switch high power.
am i right?
 
thanks guys for your patience with me. i don't really like this part of diy. to be honest searching for some of the needed parts makes my blood boil. it's frustrating when i don't know.
i understand now at first i thought irfp240/9240 was one number. that is why no search results.
why are these so cheap ?
isn't there any better top end ones to use?
maybe they are fine i don't know. i would just guess that there must be better quality that cost more somewhere.
these exicon version in the p101 were like $23 each so the irfp at $3.10 seems cheap
 
They are completely different technology inside. Laterals are always much more expensive than Hex-FETs. Both have got certain advantages and disadvantages, requiring different approaches in output stage design.

See my recent CFA design here (live measurements):
>With Laterals<
>With Hex-FETs<

Both are very high-performance. There are minor differences, if you look carefully, but they are insignificant. The fact IRFPs are cheaper doesn't mean anything. They are excellent output devices if used properly.

Cheers,
Valery

P.S. OPS schematics are not shown there, but I can drop you the links, if you are interested ;)
 
thanks guys for your patience with me. i don't really like this part of diy. to be honest searching for some of the needed parts makes my blood boil. it's frustrating when i don't know.
i understand now at first i thought irfp240/9240 was one number. that is why no search results.
why are these so cheap ?
isn't there any better top end ones to use?
maybe they are fine i don't know. i would just guess that there must be better quality that cost more somewhere.
these exicon version in the p101 were like $23 each so the irfp at $3.10 seems cheap

Electronic parts get cheaper as they become more popular. These devices have been around forever and are very popular because they are such a good device. Selecting parts gets easier fast. It's a little intimidating at first. One characteristic of a device you won't find on paper is how well they stand up to a slipped test probe or shorted speaker lead. hexfets stand up very well to that.
 
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I have two slewmaster 5 pair sets one with 240/9240 and a set with bjts 3281/1302 on semi. They are both excellent. Build with parts easily available from the big suppliers and you won't be disappointed. For a stereo pair some extra output devices to allow some matching would be nice.