The ones on stock at Mouser have different hfe classification, KSA1381ES vs KSC3503DS
Oh yeah , 100mhz/20W -SOA looks the same. So , even with a smaller package ... they might be good drivers for a single pair outputs..
The 2SC4793 with it's larger package lists as 2/20W vs 1.5/10W (TTC011).
2-3 pairs OP , I'd still go with MJE15032 (8A/50W).
If you can find the same binning ... they are the very best VAS devices (or pre-drivers).
OS
The 2SC4793 with it's larger package lists as 2/20W vs 1.5/10W (TTC011).
2-3 pairs OP , I'd still go with MJE15032 (8A/50W).
No , If you have them. I can't order them , and won't pay more $$ or fall prey to Ebay fakes.
If you can find the same binning ... they are the very best VAS devices (or pre-drivers).
OS
Protection , Protection.
Time to design the 2 "business ends" of the Arcwelder protection scheme.
- Arcwelder soft-start. Would be nice to to have all AC (and only AC) on it's own board.
A little education before we commit to a PCB - https://neurochrome.com/pages/the-ultimate-guide-to-soft-start-design and ...
EMI filters - https://www.electronicproducts.com/all-about-emi-filters/ .
Might as well add anything "ANAL" to the design. We already will just have (+5/+12/ ground) and 3 control signals... that would be inrush/main relay
and AC sense. Just a single 6 pin connector to interface with the control unit.
Mount this board right at the rear panel (AC plug) ... all by itself.
- Arcwelder SS relay , Jwilhelm's circuit is perfect. I used it before - perfect ! 2 connectors , one for the rail reference and one for the control signals.
All that remains is the (digital) control signal PCB with the Arduino NANO. I debated on how to split this circuit up. Inspiration of actually
building a setup like this and looking at PASS amps made me come to this conclusion.
Also , if I want future "extra OCD" (ESP32) , I can just re-design a more sophisticated digital board , all the "dumb linear interfaces" remain on the existing PCB's.
OS
Time to design the 2 "business ends" of the Arcwelder protection scheme.
- Arcwelder soft-start. Would be nice to to have all AC (and only AC) on it's own board.
A little education before we commit to a PCB - https://neurochrome.com/pages/the-ultimate-guide-to-soft-start-design and ...
EMI filters - https://www.electronicproducts.com/all-about-emi-filters/ .
Might as well add anything "ANAL" to the design. We already will just have (+5/+12/ ground) and 3 control signals... that would be inrush/main relay
and AC sense. Just a single 6 pin connector to interface with the control unit.
Mount this board right at the rear panel (AC plug) ... all by itself.
- Arcwelder SS relay , Jwilhelm's circuit is perfect. I used it before - perfect ! 2 connectors , one for the rail reference and one for the control signals.
All that remains is the (digital) control signal PCB with the Arduino NANO. I debated on how to split this circuit up. Inspiration of actually
building a setup like this and looking at PASS amps made me come to this conclusion.
Also , if I want future "extra OCD" (ESP32) , I can just re-design a more sophisticated digital board , all the "dumb linear interfaces" remain on the existing PCB's.
OS
Attachments
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What would be the best input stage for achieving a little 'honey'?
That is to say yummy distortion.
That is to say yummy distortion.
Oh , by the way - I'm about to build ... did not abandon this project !
Working on the rest of the protection system (below) and
I will post the SYMASUI , EASYAMP TH , and the INFIDEL
- 5 IPS's.
I want to have a complete setup for a complete OEM+ quality amp . NO sloppy DIY "kit".
Working on the rest of the protection system (below) and
I will post the SYMASUI , EASYAMP TH , and the INFIDEL
- 5 IPS's.
I want to have a complete setup for a complete OEM+ quality amp . NO sloppy DIY "kit".
Attachments
Symasui will be next... (just a BOM). Interest of the Maplin (I did not know) and Hitachi topology has surfaced recently.
I just thought it was the "symasym" DIYA project that I was familiar with.
Maplin/Hitachi were real simple like the "HH" English V600-800 LATFET models. (below)
This seem to be a "lazy" design (that works).
Just a few more parts equals something that could match or BEAT the mighty Wolverine.
10K is 1/2 ppm , gain is 80 DB (below 3/4)
1K gain is 120db with PPB (billion'th) , can't really even measure it with the simulator ... 0 % ??
I'm going to order "Hellraiser" CFA as my first choice boards. I remember them from slewmaster.
They had such a crystal clear sound. Not really bright , but very detailed.
In the BASS department , CFA feeds back EMP to the emitters of the negative FB point , correcting for the speaker (big woofer)...
These "Symasui's" , just to export a couple to the Wolverine people . My test setups could not measure
this design. Wolverine team even runs up on the DAC/noise floor limitation. These should be the same.
They DO clip better (last pix) , these are just the Wolverine input stage with a balanced differential VAS - perfect balance.
OS
I just thought it was the "symasym" DIYA project that I was familiar with.
Maplin/Hitachi were real simple like the "HH" English V600-800 LATFET models. (below)
This seem to be a "lazy" design (that works).
Just a few more parts equals something that could match or BEAT the mighty Wolverine.
10K is 1/2 ppm , gain is 80 DB (below 3/4)
1K gain is 120db with PPB (billion'th) , can't really even measure it with the simulator ... 0 % ??
I'm going to order "Hellraiser" CFA as my first choice boards. I remember them from slewmaster.
They had such a crystal clear sound. Not really bright , but very detailed.
In the BASS department , CFA feeds back EMP to the emitters of the negative FB point , correcting for the speaker (big woofer)...
These "Symasui's" , just to export a couple to the Wolverine people . My test setups could not measure
this design. Wolverine team even runs up on the DAC/noise floor limitation. These should be the same.
They DO clip better (last pix) , these are just the Wolverine input stage with a balanced differential VAS - perfect balance.
OS
Attachments
I saw you mentioning a wolverine pre-amp was in the works! Is that still a thing? I ordered an ACP+ as one of my first builds.
Yeah , If I ran either a Wolverine/Symasui IPS through a BD139/140 class A headphone pre-amp/headphone output stage ....
I could really blow away any ACP+ , match that with "Jung super regulator" +/- 15V supplies wow !! -150thd plus -150 PSRR.
Edit - that is the Symasui test - .1V (+10db like a preamp) 2nd harmonic down @ 160db 1K ... noise floor territory -
OS
I could really blow away any ACP+ , match that with "Jung super regulator" +/- 15V supplies wow !! -150thd plus -150 PSRR.
Edit - that is the Symasui test - .1V (+10db like a preamp) 2nd harmonic down @ 160db 1K ... noise floor territory -
OS
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Hi Peter,as i have so many IPS from Slewmaster days i want to ask.
Can i use some of them as preamplifiers?
What is need to add in the output circuit?
Can i use some of them as preamplifiers?
What is need to add in the output circuit?
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Just a BD139/140 pair biased into class A with 22R emitter resistors. Then you feedback 4.7K (instead of 22-27K) to NFB.
You would want the class A the be of the current regulating variety with a touch of thermal feedback.
Not exactly like the below schema , but generally a diamond buffer (fast) based with some form of thermal FB.
(op-amp) is replaced with the IPS.
Edit - I might add a dual line-stage to the Arcwelder family - plug in some symasui's.
OS
Attachments
Just a pair LM7824/LM7924 with ample decoupling and a little 24-0-24 trafo and either the spook or hellraiser IPS
would typically be -120db+ separation and -135db THD + noise.
Would easily beat anything out there ... you would have to spend 10X the money just to (be able) to test it.
OS
would typically be -120db+ separation and -135db THD + noise.
Would easily beat anything out there ... you would have to spend 10X the money just to (be able) to test it.
OS
Attachments
OS,
did you ever do anything else with your version of the APT1 input stage? I always liked the APT1 front end and was interested that you played around with it for a while. I just don't remember if you "finished off" a design of it ....
did you ever do anything else with your version of the APT1 input stage? I always liked the APT1 front end and was interested that you played around with it for a while. I just don't remember if you "finished off" a design of it ....
The apt 1 was the inspiration for my folded/Hawksford cascode (with the leds) that is on the spooky and hellraiser,
APT 1 just uses fixed diodes with no local FB loop - it works but is inferior.
The APT 1 also uses a level shifter to achieve a symmetric VAS , the hitachi (symasui method) is "alien tech" compared
to that.
Still , the APT 1 was one of the topologies that i worked from , it was also a triple EF ... yummi.
OS
APT 1 just uses fixed diodes with no local FB loop - it works but is inferior.
The APT 1 also uses a level shifter to achieve a symmetric VAS , the hitachi (symasui method) is "alien tech" compared
to that.
Still , the APT 1 was one of the topologies that i worked from , it was also a triple EF ... yummi.
OS