Slewmaster - CFA vs. VFA "Rumble"

Slew2-pair "baby" with to-220 drivers.

This one is the equivalent of the HK680r -exactly !!

Sanken OP's + toshiba drivers = 105W/8R @ 50V+ rails (HK specs).
Priced this one out - 30-40 $USD - ready to rock.

I own the HK .... This OPS has the best thermal stability I've seen.

OS
 

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And the "MONSTER" ....

This one is no B$ ...
NOT for the faint at heart ...

85V rails - 12A fuses , and 16/14ga copper wire busses.
More room for the driver heatsink and power resistors.

250/500W with MJL21193/4 or Semilab MGxxxx (300/600W).

Very similar to the H/K990 , which is rated 200/400W (conservatively).
Fits on "heatsink USA" 250mm extrusion .... 100$USD for
1/2 a 2500$ amp .....
If I was rich - this would be mine. 😀

OS
 

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  • SLEWMASTER5-P-V1.2.zip
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  • slew5final.JPG
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This one is no B$ ...
NOT for the faint at heart ...

85V rails - 12A fuses , and 16/14ga copper wire busses.
More room for the driver heatsink and power resistors.

250/500W with MJL21193/4 or Semilab MGxxxx (300/600W).

Very similar to the H/K990 , which is rated 200/400W (conservatively).
Fits on "heatsink USA" 250mm extrusion .... 100$USD for
1/2 a 2500$ amp .....
If I was rich - this would be mine. 😀

OS




is there any file in pdf format Uncle Os,? .thank.
 
Ostripper,
I'm with you on the PDF thing, I hate to use Adobe products, only use the pdf viewer when I have to look at something. They are worse than Microsoft in exploits, there programs have to be patched weekly it seems.

I solved the LTSpice install at 2:30 last night, it was my virus checker stopping the program from unzipping without any warnings or indication it was doing anything. Shut it down long enough to install the software and now all is fine. Now to figure out how to use it, back to Bob Cordell's great amplifier book for some reading.
 
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That why I post these .... download at will.
Show the pictures when your smiling !!

These are "first time" run ... projects - NO errors.

V1.2 IPS's are next...
OS
Waiting for IPS's....and my next project is on the road:djinn:
I can't stop....
just a moment i see two tranz. Q103 NAMED VAS Vbe and Q104 NAMED OUT Vbe .Are these, Q103 IN THERMAL contact with Vas and Q104 mounted on the down side in thermal contact with outputs(on main heatsink)?
Best regards.
 
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Ostripper,
I'm with you on the PDF thing, I hate to use Adobe products, only use the pdf viewer when I have to look at something. They are worse than Microsoft in exploits, there programs have to be patched weekly it seems.

I solved the LTSpice install at 2:30 last night, it was my virus checker stopping the program from unzipping without any warnings or indication it was doing anything. Shut it down long enough to install the software and now all is fine. Now to figure out how to use it, back to Bob Cordell's great amplifier book for some reading.

Do you want a pre- tested .asc to run ??
Here is NAF's CFA with the servo ....
Make sure you have the text and asc file in the same place. The amp's asc.
has .include slewmaster.txt (the models).

Virus program ??? I don't have no virus program .... they are virus's.
If you are a little wise , and don't fall for "social engineering" tricks .. no
virus will come .. W7 /chrome are very resistant.
OS
 

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Waiting for IPS's....and my next project is on the road:djinn:
I can't stop....
just a moment i see two tranz. Q103 NAMED VAS Vbe and Q104 NAMED OUT Vbe .Are these, Q103 IN THERMAL contact with Vas and Q104 mounted on the down side in thermal contact with outputs(on main heatsink)?
Best regards.

Yes the Q103 is the driver Vbe , it alters the thermal scaling of the main Vbe
(Q104). Q104 goes under the PCB (screwed down) it is about 30-35mm away from the
first OP. Same as the 680/990 HK.

OS
 
Thanks OS,
The file opened right away in ltspice by default.

As far as no viruses in Win7 you could be right but someone from one of my linkedin groups got me with some damned hidden file that drove me nuts opening IE when I was in another browser showing me some damned ads! Took a while to find the hidden file, they are sneaky for sure.
 
OK - a perfected NAF/NAD !!

He did V1.0 , here is V1.2.

Very verbose schema with VAS current "guide". Servo highlighted.

More room for servo , decoupling closer to IC ... better grounding.
Work of "art". 😀

PS - NAF even used (wrong) 68R cascode Re , amp DID NOT smoke - my mistake.
All this is corrected. Amp was developed in the "CFA discussion" thread.
Thumbs up from Cordell himself ... 🙂
EDIT - I made a couple tweaks to this design ... now at 6-8ppm THD20 1/2 power 4R !!
Red led's naf used were 1.8+ vf , this increased CCS I , 820R for R13/16 will negate this oversight.
OS
 

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  • NAD-S-V1.2-schema.jpg
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  • NAD-S-V1.2.zip
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