Hello again to all, I just want to make an observation about the A60 and A60+ packs that are sold, yesterday when I was looking at some bags of transistors that I have, I had on the table the ones that I unsoldered from the A60 board, and out of curiosity I looked at the gains and others, My surprise was (especially in the A60) that all the transistors are perfectly paired, having the TTc5200 111Hfe one channel and 113 the other, and for the TTa1943 107 and 108, the exact trios, and the complementary with 1% +/-, that can only be done when you handle a lot of quantity, and it is also time to do it.
As for the transistors, I compared them with others of the same Mouser and similar gains, weight, and non-magnetic, the reason for all this, is that if they are so paired the result is much better than if they are not (in theory), and the complementary ones so the phase shift is more homogeneous, I say this without having heard them yet, only by the impressions of the thread, maybe it can be one of the reasons for its warmth, greetings.
As for the transistors, I compared them with others of the same Mouser and similar gains, weight, and non-magnetic, the reason for all this, is that if they are so paired the result is much better than if they are not (in theory), and the complementary ones so the phase shift is more homogeneous, I say this without having heard them yet, only by the impressions of the thread, maybe it can be one of the reasons for its warmth, greetings.
Good morning friends, I would be interested in the A60+ version; first of all I seem to have understood that the final scheme is this one published by M0rten on 1 August 24, and there have been no more changes, is this correct? Then I wanted to know if anyone had come up with the measured specifications, because I couldn't find them on this thread. Thanks for all the information you give me. Kind regards to everyone Ros
Looks like this circuit should at least work , but it is the most "grade school" version of CFA circuit designs.
The forum designers were at this level 20 years ago.
(BELOW) is what it should be.
This topology can be as perfect as the forum's Wolverine/badger .... even close to a Topping B20.
1PPM 1K - 8PPM 20Khz worst case. They are super stable and soft clip , too !
The Chinese are good at making the PCB's , boy !! do they suck - at design !!
OS
The forum designers were at this level 20 years ago.
(BELOW) is what it should be.
This topology can be as perfect as the forum's Wolverine/badger .... even close to a Topping B20.
1PPM 1K - 8PPM 20Khz worst case. They are super stable and soft clip , too !
The Chinese are good at making the PCB's , boy !! do they suck - at design !!
OS
Attachments
Hellraiser is born out of the CFA vs.VFA thread 14 years ago. I designed it to
stand up to the forum "best amp" (wolverine) and to dispel whether one "sounded" better
than the other.
It's actually the very coolest amp in the way it overloads , red led VAS clips nice all day.
can't kill this amp. AND , it is the fastest amp @ 300+ V/uS slew rate.
Servo is ZERO offset , uses current mirrors to auto adjust bias/offset. Red led's offset tempco
in every stage. Regulated 12V input stage has -120DB PSRR !
PS - I have one of these amps , running for 14 years straight. perfect.
Cool looking input stage when it is running (below).
I actually looked at some old accuphase circuits as inspiration for this design.
OS
stand up to the forum "best amp" (wolverine) and to dispel whether one "sounded" better
than the other.
It's actually the very coolest amp in the way it overloads , red led VAS clips nice all day.
can't kill this amp. AND , it is the fastest amp @ 300+ V/uS slew rate.
Servo is ZERO offset , uses current mirrors to auto adjust bias/offset. Red led's offset tempco
in every stage. Regulated 12V input stage has -120DB PSRR !
PS - I have one of these amps , running for 14 years straight. perfect.
Cool looking input stage when it is running (below).
I actually looked at some old accuphase circuits as inspiration for this design.
OS
Attachments
Interesting. There is a lot of parts in the circuit, but it does have elements which I can see in the A60 as well and I tracked down the Spooky frontend, dang, that Wolverine thread has been going for a long time now.
good morning to all guys, hello ostripper. First of all, thanks for the reply. I've seen THE wolverine and I really like it; I would have no problem making it, but I find it demanding in terms of time (my time obviously). I would like to go with something a little simpler, like your hellriser; the circuit is beautiful: it also seems very high-performance. I believe this is the final circuit, with all the changes made, can you confirm that? with your permission I will bother you again to ask you for some clarification of implementation. For now, thanks again. A good day to all guys. Un saluto Ros ( pausa caffè 🙂
Go for it. Hellraiser is golden !
Hellraiser is the same as the spooky , except for the buffer (CFA).
As far as high performance , the Hellraiser is so fast , it can correct an underbiased output stage.
Runs cool , too. VAS is 3.8mA. The whole input stage just uses <20mA per rail.
Actually , these designs are the best tradeoff between complexity and performance.
Most sections of the design have dual uses. Like , the servo regulators also run the first stages as well
as the op-amp. The VAS will stay 3.8mA from 0C to 40C easy .. very thermally stable.
Made to last forever !!
OS
Hellraiser is the same as the spooky , except for the buffer (CFA).
As far as high performance , the Hellraiser is so fast , it can correct an underbiased output stage.
Runs cool , too. VAS is 3.8mA. The whole input stage just uses <20mA per rail.
Actually , these designs are the best tradeoff between complexity and performance.
Most sections of the design have dual uses. Like , the servo regulators also run the first stages as well
as the op-amp. The VAS will stay 3.8mA from 0C to 40C easy .. very thermally stable.
Made to last forever !!
OS
Judging by the latest comments, it's not for nothing that we're collecting a copy of Accuphace. If it's compared to such monsters.
ostripper you almost convinced me 🙂
Can you kindly provide me with a link where I can find documentation (schematic, bom, specifications, other) for the creation of hellraiser, please? possibly also receive it via email....thanks again, un saluto Ros
Can you kindly provide me with a link where I can find documentation (schematic, bom, specifications, other) for the creation of hellraiser, please? possibly also receive it via email....thanks again, un saluto Ros
Where can we buy PCBs?
I already have two Wolverine PCBs and all components from Mouser. I plan to build it, hopefully, during Spring/Summer 2025 when I gather enough skills for such project, and have more time too.
https://www.diyaudio.com/community/...smd-60w-amps-wolverine-compatible-ips.398785/
They are all in there. Spooky - hellraiser - infidel (cheap wolverine) , and the not finished "symasui".
Symasui might be the king of all amps ! Can go better than topping @.1 PPM 1Khz. It is a Hitachi , Sansui , Pioneer
general 80's circuit with newer design/parts...
Strange , I also have the sim of Wolverine , can only get 1-2 PPM. The finished real world amps do .2 to .4 ppm !
Input stages are (big) SMD , outputs are small wolverine EF3's.
Edit - most of these come close to the Toppings (b10-20) and the benchmark AB-1. 2-3K$ amps for a few hundred.
OS
They are all in there. Spooky - hellraiser - infidel (cheap wolverine) , and the not finished "symasui".
Symasui might be the king of all amps ! Can go better than topping @.1 PPM 1Khz. It is a Hitachi , Sansui , Pioneer
general 80's circuit with newer design/parts...
Strange , I also have the sim of Wolverine , can only get 1-2 PPM. The finished real world amps do .2 to .4 ppm !
Input stages are (big) SMD , outputs are small wolverine EF3's.
Edit - most of these come close to the Toppings (b10-20) and the benchmark AB-1. 2-3K$ amps for a few hundred.
OS
Attachments
Last edited:
Thanks for providing the info on availability of the PCBs.
I will build one of these before starting Wolverine project.
These are quite similar to the Wolverine.
Any of these can be plugged in to any wolverine output stage. I made everything reverse compatible.
Output stages are the refined Harmon-Kardon 680 EF3 based style (same as wolverine).
Spooky is "Leach" ( RIP ) - refined.
Hellraiser is A-60 CFA based.
Infidel is wolverine with LED CCS and cascode. your choice of feedback.
Symasui is just bad A$$ !
SMD IPS's can be <20$ each with the best parts. SMD silver mica's can go for 2-4$ each.
I use the 1206 and the largest SMD packages for the input stages. SMD can be small , reduce trace length (noise) ,
Most SMD is cheap ( VAS semi's = 1$) Dual packages can be pre-matched.
OS
Any of these can be plugged in to any wolverine output stage. I made everything reverse compatible.
Output stages are the refined Harmon-Kardon 680 EF3 based style (same as wolverine).
Spooky is "Leach" ( RIP ) - refined.
Hellraiser is A-60 CFA based.
Infidel is wolverine with LED CCS and cascode. your choice of feedback.
Symasui is just bad A$$ !
SMD IPS's can be <20$ each with the best parts. SMD silver mica's can go for 2-4$ each.
I use the 1206 and the largest SMD packages for the input stages. SMD can be small , reduce trace length (noise) ,
Most SMD is cheap ( VAS semi's = 1$) Dual packages can be pre-matched.
OS
Post #826 ??
That's the "bomb".
Possibly the most advanced CFA design on earth.
Same with the wolverine , Doug Self must like that - AB1 and topping level.
I do have Hellraiser stuff - here - https://www.diyaudio.com/community/...ne-compatible-ips.398785/page-34#post-7686815
there it is ....
If y'all like these PPM amps , I will interact with Y'all !! cool.
OS
That's the "bomb".
Possibly the most advanced CFA design on earth.
Same with the wolverine , Doug Self must like that - AB1 and topping level.
I do have Hellraiser stuff - here - https://www.diyaudio.com/community/...ne-compatible-ips.398785/page-34#post-7686815
there it is ....
If y'all like these PPM amps , I will interact with Y'all !! cool.
OS