TL071 .... $.62c
below is the damage ...
Same # of parts , did not need the IC Vcc diodes/e-caps ... just used .1u decoupling caps
at the IC Vcc-/+ - left the protection diodes at +/- IC input.
With a Jfet op-amp , 680k input resistor (real high-Z) ... smaller integrator
cap -2.2u.
Simulation is 20ppm 10hz - HF (much cleaner LF!)
No trimmers needed.
Improving the amplifier with current sources penalized me with "resistance"
to manually adjust offset. A resistive loaded Diamond would be easier to
adjust with a trimmer.
The NX (I was told) ... will start at 15mv and settle with time to 1-2mv.
This one will stay <1mv- regardless !!
PS - I don't wan't to make a "toy" for an amp - It should excel in every
aspect.
OS
Attachments
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ostripper,
Why not combine CFA with Class A. I have anjoyed what I believe to be a quality CFA design in the TSSA v1.6 and it sounded wonderful. You could tell it was a high bandwidth design with wonderful clarity and pace. What it did not have was body and soul and from my limited experience, this tends to be a fault of AB designs.
Why not combine CFA with Class A. I have anjoyed what I believe to be a quality CFA design in the TSSA v1.6 and it sounded wonderful. You could tell it was a high bandwidth design with wonderful clarity and pace. What it did not have was body and soul and from my limited experience, this tends to be a fault of AB designs.
I haven't labeled yet , but it's a goin' on 
(below 1/2).
Circled resistors can be 2/3/5 or 25- 50W !
... (to-220/5mm LS -below 3) ha !
Can a servo be "tricked" ?? Going from 0V, (no signal) to a 20-200hz full
power (120Vp-p) signal ... the first 2-3 waveforms are offset at .1-.2V.
After 4-5 cycles , all is well at the <1mV range again.
This "settling time" only happens at LF and with a large transient at LF. It is caused
by the charging of the integrator cap C3 at U1. Reducing this cap brings LF
rolloff up into the audio range.
2.2uf has rolloff of about 5 hz , 1hz is down 15db.
For this design , we are nearing the best quality to price ratio. DON'T
let a small IC scare you. As I have stated , the ne5532 servo in my
japanese unit has been "servo-ing" for 33 years.
OS
(below 1/2).Circled resistors can be 2/3/5 or 25- 50W !
... (to-220/5mm LS -below 3) ha
!Can a servo be "tricked" ?? Going from 0V, (no signal) to a 20-200hz full
power (120Vp-p) signal ... the first 2-3 waveforms are offset at .1-.2V.
After 4-5 cycles , all is well at the <1mV range again.
This "settling time" only happens at LF and with a large transient at LF. It is caused
by the charging of the integrator cap C3 at U1. Reducing this cap brings LF
rolloff up into the audio range.
2.2uf has rolloff of about 5 hz , 1hz is down 15db.
For this design , we are nearing the best quality to price ratio. DON'T
let a small IC scare you. As I have stated , the ne5532 servo in my
japanese unit has been "servo-ing" for 33 years.
OS
Attachments
Those AB stages were not this EF3 OPS. It is highly reviewed and
used by Marantz , harmon/Kardon and sansui.
Very warm and powerful BJT bass. Plus 30 year durabilty (I own 2).
OS
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You mean the thick film 25 watter. Bob "turned me on" to these.
My 2 choices are :
http://www.ohmite.com/cat/res_tbh25.pdf
or .. for the poor (like me) ...
http://www.irctt.com/file.aspx?product_id=36&file_type=datasheet
My pcb will take em' all ...
It's done ...
OS
"SYMASUI-CHI"
Thank you !
Please check out above artwork and material. It could have bug (s).
next is wolverine and "symasui-chi " ,
a unique blend of many designs .....
Part Symasym and part sansui , this "MONGREL" is a beast.
Belts out PPM THD and is so simple !
First installment "AMP of the day " saga .... ha ha
(I have 100's)
Later I will post .ASC for this little gem and completed CFA-nad "slewmaster".
OS
Thank you !
Please check out above artwork and material. It could have bug (s).
next is wolverine and "symasui-chi " ,
a unique blend of many designs .....
Part Symasym and part sansui , this "MONGREL"
is a beast.Belts out PPM THD and is so simple !
First installment "AMP of the day " saga .... ha ha
(I have 100's)
Later I will post .ASC for this little gem and completed CFA-nad "slewmaster".
OS
Attachments
Without the white silk gloves.
The "amazing - unique" - "SLEWMASTER" !!
BELOW... 300dpi .bmp for printing (copper) , schema , and silk/parts (topside color). "Slew-OPS" is the EF3 and "Slew-nadH" is the IPS.
OS
Please check connection of R110 on your PCB (Slew-OPS). Is it different from your schema?
Thank you very much uncle Os... i've been following your thread from supersym, mongrel to honeybadger i learn much from your thread and suddenly you dissapear... how sad i'am
And now comeback with this unique Slewmaster combo ...complete with CFA and VFA
i'll start collect part to build this beast.
And now comeback with this unique Slewmaster combo ...complete with CFA and VFA
i'll start collect part to build this beast.
THANK you !!!
It would of worked with that mistake - but not as well . Now R110 goes from
emitter to emitter (Q105/106) and now R111/112 JUST go to the driver bases
(Q107/108).
I added the stoppers later in the design - my mistake.
ALL fixed - "Slew-ops-V1.1"
.AND ... added a cap to the CFA "NAD-H" servo.
Both are below , any more errors - please tell !
OS
Revelations !
I looked at the akaido headphone amp -Aikido SLPS & Hybrid Headphone Amplifier
...and many other diamond buffer based power and headphone amps.
They all use the inverting integrator DC servo (as my circuit does).
A "trick" to improve operation is to increase R9 to 470-680K on the
slewmaster IPS. AC is down into the nanovolts from the IC ... you would most
likely see worse on your "clean" ground rail or supplies.
The IC has to increase the DC at this point which makes the "settling time"
of the servo less , as well as being a more accurate at LF .
For the VFA .... COME on , CHOOSE !
The Symasym/Sansui hybrid or the Wolverine /"blameless" ...
Both are proven ppm VFA amps. They DO not suffer from any "DIY" shortfalls
(thermal or offset).
Some amps on the forum do fall short of what has to be designed for
the "market" ... I know about DC/overload protection but what about
long term precision stability.
I would like to see some of these other DIY amps stay the same from
my 0C garage to my 35C flower room !! (Offset and bias ).
The Badger was tested from the snowbank to the heat of summer.
Enough "rant" .. bye !
OS
I looked at the akaido headphone amp -Aikido SLPS & Hybrid Headphone Amplifier
...and many other diamond buffer based power and headphone amps.
They all use the inverting integrator DC servo (as my circuit does).
A "trick" to improve operation is to increase R9 to 470-680K on the
slewmaster IPS. AC is down into the nanovolts from the IC ... you would most
likely see worse on your "clean" ground rail or supplies.
The IC has to increase the DC at this point which makes the "settling time"
of the servo less , as well as being a more accurate at LF .
For the VFA .... COME on , CHOOSE !
The Symasym/Sansui hybrid or the Wolverine /"blameless" ...
Both are proven ppm VFA amps. They DO not suffer from any "DIY" shortfalls
(thermal or offset).
Some amps on the forum do fall short of what has to be designed for
the "market" ... I know about DC/overload protection but what about
long term precision stability.
I would like to see some of these other DIY amps stay the same from
my 0C garage to my 35C flower room !! (Offset and bias ).
The Badger was tested from the snowbank to the heat of summer.
Enough "rant" .. bye !
OS
"Tuned" the Servo !
Never used a servo before. Looking at a lot of OEM ones -
equal resistance between in/out seems to be the ticket.
They all use the 1uF integrator cap , as well.
(Below)-is the best that can be done ! (nV static)
PS - noise is from the amplified Diamond buffer.
Another revelation .. one could buy 8 of these op-amp's with what a
big cap and precision trimmer would cost ($6.30usd).
OS
Never used a servo before. Looking at a lot of OEM ones -
equal resistance between in/out seems to be the ticket.
They all use the 1uF integrator cap , as well.
(Below)-is the best that can be done ! (nV static)
PS - noise is from the amplified Diamond buffer.
Another revelation .. one could buy 8 of these op-amp's with what a
big cap and precision trimmer would cost ($6.30usd).
OS
Attachments
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