Slewmaster - CFA vs. VFA "Rumble"

low voltage rules , any slewmaster I ran at 40-50v ran so cool.


This is why I contemplate class D for a massive sub and two small (SMD)wolverines
at <50v for my channels.
Right now I am locking down my Xeon music server @ 50K flacs , got to have a
killer source.


Less can sometimes be more , minimalist I have become.

OS
 
low voltage rules , any slewmaster I ran at 40-50v ran so cool.


This is why I contemplate class D for a massive sub and two small (SMD)wolverines
at <50v for my channels.
Right now I am locking down my Xeon music server @ 50K flacs , got to have a
killer source.


Less can sometimes be more , minimalist I have become.

OS

Welcome Boss!
SMD Wolverine! I think Jeff can help doing this easily 🙂
He is an smd expert!
 
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I have been doing SMD mods on PC cards bought on EBAY. SMD is cool and compact.
A real price breakthrough for HTPC's.
New (outdated haha)
-Xeon 3450
-Intel WG55 MB
-16GB ram
-2 helium hitachi 4TB drives
-1 SSD
-asus GT760 video
-asus sound card

Nice quiet led fans and antec case -
All for 280usd.Wow.


I even get to make some music now (moog-below) with my 20$ USB velocity sensitive
keyboard. So ... 300$



This deserves a nice audio setup (amps , sub). Very happy !
Also run the wolverines with an SMPS , heck with bulky trafos

(second pix) Cool and quiet to match my silent server.


OS
 

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Nice Boss, very nice.
Yes, soldering smd is an easy work, i have solder many Jeff's, Valery's IPS.
What is this SMPS, how match money?
Have you test this together with slewmaster?
Have you any new idea?😎
Best Regards.
Your simulation program. 🙂
 

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Will fire up LT spice again.

- The wolverine 2


Super high precision "blameless" style IPS with -


1 - precision voltage independent (IC reference) VAS current source.
We will use a chip - oh no !

2 - cascoded super-pair for the "active half" of the VAS.
The VAS cascode will allow a dual smd npn/pnp device AND allow for low voltage
devices. Clip behavior should be like the CFA IPS's - no saturation.


3-same input LTP/cascode as the original wolverine - I might add a servo to
eliminate any adjustments.


Goals of this IPS are to allow "idiotproof" 20- 70v operation while
having better clipping behavior than the last generation Doug Self design (no saturation diode like the badger).



You might see this first new design in 6-8 hours.


OS
 
Nice Boss, very nice.
Yes, soldering smd is an easy work, i have solder many Jeff's, Valery's IPS.
What is this SMPS, how match money?
Have you test this together with slewmaster?
Have you any new idea?😎
Best Regards.
Your simulation program. 🙂


That looks like a small SMPS ,a 5$ one on ebay.
That big one I showed is +/- 50v @ 6amps. For 50$ ,used 30+$.



SMPS's for amps would have ripple under load above the audio spectrum -

over 50khz for most ebay smps's.
Even the worst psrr in a IPS would equate to dual mono level crosstalk with an SMPS.


I will bring the SMPS and the Wolverine 2 to project level soon - lets enter
the 21'st century.
PS - new OP stage (low RDS super fast class G). 200W with 1 pair of outputs.
unless you have a disco party - just a small heatsink. I think we can come close to class D efficiency . NO big heatsinks or trafo's allowed.



OS
 
almost there ...

(below) I DID start on a wolverine 2 over 2 years ago - forgot.


The schematic shows the wolverine with a full symmetric super-pair .


Too many components.


- "flip" the input stage (LTP) around and unify both classic current sources
(Q1/2 and Q29/Q10) to be controlled by one precision IC current source -
there goes a dozen components. Q10 will just be an emitter follower for the IC,
and Q28/13/11 will not change - they will be the active half of the VAS.


After this , might also offer Jason an "upgrade" to the DIYA Badger kit including
both this V2 "blameless design" and an EF3 OPS to really get the class AB juices flowing.



For us , I want try the class G OPS. 😱
Single pair of NJW's for 100's of watts is appealing to me. Ha ha , A 2kg amp
That can hold it's own against a 30kg behemoth - this needs to be done.

WOW! The Xeon server simulates LTspice so fast , I thought there was a problem.
50ms even to get an FFT , yikes - corporate hardware is way better than consumer
stuff. I can't see why anybody would need 20 core 1000$ new processors unless they
be a mining bitcoin or something.


OS
 

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(below) I DID start on a wolverine 2 over 2 years ago - forgot.


The schematic shows the wolverine with a full symmetric super-pair .


Too many components.


- "flip" the input stage (LTP) around and unify both classic current sources
(Q1/2 and Q29/Q10) to be controlled by one precision IC current source -
there goes a dozen components. Q10 will just be an emitter follower for the IC,
and Q28/13/11 will not change - they will be the active half of the VAS.


After this , might also offer Jason an "upgrade" to the DIYA Badger kit including
both this V2 "blameless design" and an EF3 OPS to really get the class AB juices flowing.



For us , I want try the class G OPS. 😱
Single pair of NJW's for 100's of watts is appealing to me. Ha ha , A 2kg amp
That can hold it's own against a 30kg behemoth - this needs to be done.

WOW! The Xeon server simulates LTspice so fast , I thought there was a problem.
50ms even to get an FFT , yikes - corporate hardware is way better than consumer
stuff. I can't see why anybody would need 20 core 1000$ new processors unless they
be a mining bitcoin or something.


OS
Ha ha,i must order some photoresist pcb again!
I wish Jeff will draw an smd board according to this wolverine 2!:santa2:
Pete i'm really glad you are good and you are with us again.:cheers:
 
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got it -

[image 1] is the clamped output of a super-pair "blameless" IPS.


[image 2] - I had to go back to the Koda 261 amp , this is where I was
enlightened to this design trick. Some said the super-pair was a little unstable
in this amp .... but there is a group that modifies these old vintage units and
they showed that this can be mitigated.


[Image 3] A very simple 10 device IPS. Q9 in the superpair clamps both Q10
and Q8 with a hard clip. Q9/10 as a super-pair give <10ppm @20k and the same
high gain as the original "blameless" darlington.

A good simple project for beginners , better than the original.


OS
 

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Nah , documentation was my shortcoming. The slewmonster had no "special parts" , just what was on the schema.


ohh , I still have it (below).
PS- same as Jeff's boards. I built 2 , flawless.
Edit - "B" on schema was for mosfet implementation.
OS
 

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