huh ...... didn't got to that yet .... tomorrow ?
all in all , most problems aren't in price sum , but in difficulties to get most critical parts, both in time and without ridiculous expenses ...... where expense is not problem per se , but me feeling as idiot
so , acquisition planning is not yet finished , so can't tell precisely; also don't want any Greedy Boy feeling as idiot , sending me any sum of money
in fact - I'm really happiest when I can help you to make your own - from very ground up, whatever you're building ....
all in all , most problems aren't in price sum , but in difficulties to get most critical parts, both in time and without ridiculous expenses ...... where expense is not problem per se , but me feeling as idiot
so , acquisition planning is not yet finished , so can't tell precisely; also don't want any Greedy Boy feeling as idiot , sending me any sum of money
in fact - I'm really happiest when I can help you to make your own - from very ground up, whatever you're building ....
if you're young fart , just without experience ...... everything is easy , with some practice (but do the same on something else , exactly for practice)
if you're old fart , as Moi , just without experience ..... you'll loose your temper , toss everything and go to relax making bates for fly-fishing ..... in which way you can't ruin matched tiny little bastards
oh , yes - some patience , hot air SMD soldering station , some liquid solder .... you can do that
though - in case of JFets , you need to match them first
if you intend so , look at gadget shown in post #51 ...... pretty much basic JFet matching by Idss schematic is used
if you're old fart , as Moi , just without experience ..... you'll loose your temper , toss everything and go to relax making bates for fly-fishing ..... in which way you can't ruin matched tiny little bastards
oh , yes - some patience , hot air SMD soldering station , some liquid solder .... you can do that
though - in case of JFets , you need to match them first
if you intend so , look at gadget shown in post #51 ...... pretty much basic JFet matching by Idss schematic is used
Russellc asked , over in Official M2 schematic thread :
so :
this days .....thinking about it ....
it can be done ,though not exactly for cheap , considering matching and soldering tiny smds and pretty much low numbers nature of venture
so , viable offer could be :
A:
-pcbs with presoldered most critical components (all smd ) - input buffer and current sensing chips with surrounding filtering caps ,
-my beloved MKC caps for signal route electrolyt (10uF Silmic or Nichicon) bypass
-matched BD 139/140 cascoding bjts
B:
-same as above ,
-all (MF 0W6) resistors
-all multiturns
-all electrolytic caps (Pana, Nichicon, working on genuine Silmic for signal route)
-4 micas for outputs
-pinholders for few resistor positions ( regular buffer or Borbely's WCF option)
-IRFP outputs (damn , looking for Harris mnfctrd 9240)
-2 optocouplers
-2 7805 regs
.......... practicaly all parts on pcbs , excluding mosfet bolts and pcb bolts and signal xformers (too complicated for me to source them from anywhere in larger quantities)
to repeat 3 important things :
1.input buffer can be arranged in two ways : either as regular SE (this one having same THD spectra as complementary Toshiba buffer having 1 up and 1 down) , OR Borbely's WCF JFet buffer ; easy to change between two options, if two resistors positions are having soldered pin holders and one cap position having the same.
WCF buffer is having lower THD , but opposite K2 phase .... so flipping speaker's wires is more than advisable , to choose best for your auditory equipment
2. practically 4 options for signal autoformer (pinouts for all present on pcb):
-Edcor PC series 600:15K (same one as in original M2) , thus having gain of 6V/V
-Edcor PC series 600:600 , thus having gain of 4V/V (edit - only for this one it'll be needed few exacto cuts of traces and few tiny wire bridges soldering ;same physical layout of pins as previous one , but different electrical connection needed ..... very hard to accommodate without too much complication )
- Jensen JT-123-FLCPH (same one as in F6) , thus having gain of 4V/V
-Cinemag CMOQ-4LPC (same one as in SIT-3) , thus having gain of 4V/V
3. most important benefit of all this Berserking is unspoiled square law transfer characteristics of mosfets used , enabling significantly enlarged A class envelope (4 Ohms load - A class up to 40-ish Watts , then Klunk! up to 50W , 2 Ohm load -A class up to 20-ish Watts , then clunk up to Wattage you are brave enough to invoke ..... so less Klunk!!-ing in your sound ..... resulting in significantly lower THD comparing to regular M2 .
so , what you say ?
You can call it XA25 for Sissies , if you want
I say super duperest most all parts included with is way to go. With already having regular M2 transformers on hand, would prefer heaviest duties best sounding option, and seek out those transformers if so. Await price quote to determine if I should go back to "A" choice, but rather do this one right.
Somewhat haunted by Babblefish J and Defisit Amps, don't know if I could find proper match on outputs for Defisit anywho.
Russellc
Im an old fart and stubborn as hell. I might try it just for kicks But ok. I dont have a hot air soldering station and I expect open flame wont do
But ok. I dont have a hot air soldering station and I expect open flame wont do if you're young fart , just without experience ...... everything is easy , with some practice (but do the same on something else , exactly for practice)
if you're old fart , as Moi , just without experience ..... you'll loose your temper , toss everything and go to relax making bates for fly-fishing ..... in which way you can't ruin matched tiny little bastards
oh , yes - some patience , hot air SMD soldering station , some liquid solder .... you can do that
though - in case of JFets , you need to match them first
if you intend so , look at gadget shown in post #51 ...... pretty much basic JFet matching by Idss schematic is used
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look at Small-outline transistor - Wikipedia
this one is actually SOT23-5 , but dim. table for that one is empty on page
with some luck and proper equipment (lenses) , it is possible even to solder it with small SMD soldering iron ...... air gun station is for sissy old farts as I am*
*in this age , I prefer struggle in some other ways
this one is actually SOT23-5 , but dim. table for that one is empty on page
with some luck and proper equipment (lenses) , it is possible even to solder it with small SMD soldering iron ...... air gun station is for sissy old farts as I am*
*in this age , I prefer struggle in some other ways
nothing matched
up regular FYGFB IRFP240 of any production
down preferable FYGFB non-Vishay IRFP9240........ so Harris (mosfet gloom , or it was mist ? ...... that was as Papa called it - slight nonlinear capacitance in voltage domain )
FYGFB - means - first you grab from bag
disclaimer - I like Vishay down
up regular FYGFB IRFP240 of any production
down preferable FYGFB non-Vishay IRFP9240........ so Harris (mosfet gloom , or it was mist ?
...... that was as Papa called it - slight nonlinear capacitance in voltage domain )FYGFB - means - first you grab from bag
disclaimer - I like Vishay down
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nothing matched
up regular FYGFB IRFP240 of any production
down preferable FYGFB non-Vishay ........ so Harris (mosfet gloom , or it was mist ?
FYGFB - means - first you grab from bag
disclaimer - I like Vishay down
How many per stereo channel, doesn't this amp use irf240 and irfp9240?
Russellc
didn't follow that thread properly , but I believe basic Idss matching scheme is in case
why not - buy a bunch of them , bring proper amount of coffee , switch off the phone ..... and World is your Oyster
nothing what alive ppl can't do
(just be sure that you have where to put 5-legged critter , having two JFets inside , with sources tied together)
just edited missing IRFP9240 in previous post
one pair per channel , same as original M2
need to check ..... isn't schematic still in post#2 ?
Oh yes, but from response I wanted to make sure it hadn't been altered. Also I thought that from "beserk" it might have more outputs than regular M2.
Thanks, will await price structure...
Russellc
didn't follow that thread properly , but I believe basic Idss matching scheme is in case
why not - buy a bunch of them , bring proper amount of coffee , switch off the phone ..... and World is your Oyster
nothing what alive ppl can't do
(just be sure that you have where to put 5-legged critter , having two JFets inside , with sources tied together)
Kinku's looks like it's for 3-leg type, not 5-leg critter. I built one, was hoping for a chance to use it!
BK
Attachments
Papa taught us in several steps that source resistors are useful , doing many good things in amplifier
however , when one can do without them , its easily concluded that mosfets are often constipated with them
we need that sometimes , sometimes don't
so , you can call it Berserked M2, M2 on steroids , Sissy XA25 , Un-constipated M2, Liberated M2 , Hippy M2 , I love ya Alice B. Toklas M2 , Party M2 ......