Hi Terry ,this will be a good reason especially when use lead free solder (high temp.)
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Thanks Thimios for the answer. As far as worrying about overheating the devices I would think a quick connecting heat sink on the leads would take care of the overheating of the device. I guess if you don't have any problems with RF or some extra inductance there wouldn't be much problem with leaving the longer leads. Why use the lead free solder if you don't have to, I don't plan on using it until I am forced to do it.
I don't plan on using it until I am forced to do it
I always do the same with you my friend ,but my leaded solder wire bobbin is empty.
Some OEM's leave power passives and active devices above the board to
make for better servicing.
Those components that let the magic smoke out will cook the PCB , make
for an unsightly mess. power devices ...or, any resistor that could fail
(most of the larger lead space 1/2w-2w passives) , raise above the board
by at least a centimeter.
Might need to only clean a little "soot" off the board.
$hat can happen ??
OS
make for better servicing.
Those components that let the magic smoke out will cook the PCB , make
for an unsightly mess. power devices ...or, any resistor that could fail
(most of the larger lead space 1/2w-2w passives) , raise above the board
by at least a centimeter.
Might need to only clean a little "soot" off the board.
$hat
can happen ??OS
You need big feedback resistor. I use 2k2 || 2k2. The voltage can swing from power supply voltage to ground on these resistor (almost). I plan use +-70VDC power supply, but now tested on +-64VDC.
The reason I replied that way was because I saw it in some build guide instructions one or more times and it made sense. I use a hot iron too so I don't have to be on the part as long. I use a fine point on my soldering iron. I have a separate soldering iron with a chisel point for soldering lugs and the like that need more heat.
Hi OS,
Would you SIM with a SIM speaker load... instead of 8/4/2 ohm for load? Here is a 2-way speaker equivelent values to use (from D.Self's book) --
View attachment SKR Z model.pdf
See what happens to THD, stability etc.
THx-RNMarsh
Would you SIM with a SIM speaker load... instead of 8/4/2 ohm for load? Here is a 2-way speaker equivelent values to use (from D.Self's book) --
View attachment SKR Z model.pdf
See what happens to THD, stability etc.
THx-RNMarsh
Nothing happens to stability.
I have already done this ... at the tweeter (or woofer) , you would see
phase shift (as expected) ... determined by the X-over.
Thimios fried some slow 21195/6 OP's. The slewmaster design likes
faster OP's (30mhz +) ... obviously !
I am about to port these amps to both my sub and full range setups.
I must thank thimios ... I now know EXACTLY waht amps will go
with what speakers ..... I feel guilty , as others have done the "scary
stuff " for me.
But , for my purposes ... I can can have absolute perfection
(combining the bimo/naf/thimios preruns) with my base design.
The correlation between real world and simulation (amps) is an anology
to my subwoofers real world port length deviations (as opposed to
the actual math).
Thank you thimios (especially). My 2 primary amps will be CFA-X,
and my Sub amp will be "Symasui". I have chosen ...
I will have a killer system (I also have the real badarse speakers to match).
This has been my current project...
PS - the speakers you would match these amps to are as important as
the amps themselves ... absolutely !!
OS
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OS, don't feel guilty.
Because of you and this thread, I can learn faster. Thank you.
What I do on a amp op ....
I will run it through a 1uf cap at "ungodly" levels. Check for
un-adequately damped ringing .
Run the amp with large inductance's on the rails and as a OP load.
All these amps have no issues with these tests,
Speakers are "GOD" ... I really try to make these amps "kind" to
the "holy" drivers. Speakers are expensive ... my "lowly" amps
better be "good" to them.
OS
I will run it through a 1uf cap at "ungodly" levels. Check for
un-adequately damped ringing .
Run the amp with large inductance's on the rails and as a OP load.
All these amps have no issues with these tests,
Speakers are "GOD" ... I really try to make these amps "kind" to
the "holy" drivers. Speakers are expensive ... my "lowly" amps
better be "good" to them.
OS
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Hi thimios, can you show us the schematic of your cfa-x with complete modifed values of compensation caps and feedback resistors? I am going to iterate this build soon. My build is posted in our local forum.
SLEWMASTER Build
SLEWMASTER Build
Hi terry - i am afraid you have to diy it yourself to suite the parts available in your place, like what i have done here in cebu. Some kind guy maybe able to help you but the harder parts to determine are the pre-driver, driver, output combo. If i remember right these should be fast- slow-faster devices.