What speakers are you using? What is their efficiency?
I use full range sonido, horn loaded and infinity quatom 5...With mcintosh Ma 6100 I have greater bass fundament for comparison...
The transistors are matched toshibas Mosfets and jfets...
Right now I have 0R5 as source resistors for Mosfets but thought to lower for more power...
I have solved the bass problem a little bit, I have optocoupler volume control and this was the source of problem...
So far its interesting that M2 is driving the Infinity quantum 5...
I have solved the bass problem a little bit, I have optocoupler volume control and this was the source of problem...
So far its interesting that M2 is driving the Infinity quantum 5...
@ Diyers
By copper shield foil i mean like on this one.
M2 need care protect from all magnetic components interaction.
Experiment & find efficient solutions My best
By copper shield foil i mean like on this one.
M2 need care protect from all magnetic components interaction.
Experiment & find efficient solutions My best
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M-2 questions, Toshiba resistor change and pand preferred J Fet idss
Have completed another set of Tea's M-2 boards for a Toshiba output version and have a couple of questions.
What is the ideal idss for the Jfets used in M2? I have a set from the store, BL grade,and I have a few sets from High 8 to low 9 idss on hand... and secondly,
As these boards are already assembled with stock values, how much of a problem is NOT changing R11 to .1 R (from 100R) and R13 and R14 to .33R (from .5R) as Zen and others suggested? (See posts #891 and #902) Or just R11 changed and source resistors left at .5?(with Toshiba mosfets)
Thanks,
Russellc
Have completed another set of Tea's M-2 boards for a Toshiba output version and have a couple of questions.
What is the ideal idss for the Jfets used in M2? I have a set from the store, BL grade,and I have a few sets from High 8 to low 9 idss on hand... and secondly,
As these boards are already assembled with stock values, how much of a problem is NOT changing R11 to .1 R (from 100R) and R13 and R14 to .33R (from .5R) as Zen and others suggested? (See posts #891 and #902) Or just R11 changed and source resistors left at .5?(with Toshiba mosfets)
Thanks,
Russellc
What is the ideal idss for the Jfets used in M2? I have a set from the store, BL grade,and I have a few sets from High 8 to low 9 idss on hand
Those will work fine. The JFETs see the 24V rail, so you want to keep the IDSS under 10mA to keep them running cooler.
I don't have any experience with the Toshiba MOSFETs, so cannot comment on that.
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optocoupler thingie will set Iq , even if you use two submarines as outputs , as long they (submarines) are having proper governing electrode
so - Toshibas , IRFP , 2SJ/2SK ,FQP/FQN , whatever , even bipolars will be biased at approx. 1A2-1A3
edit : that being with original Rs values (0R47)
if you decrease Rs values , Iq will rise in same amount/percentage
so - Toshibas , IRFP , 2SJ/2SK ,FQP/FQN , whatever , even bipolars will be biased at approx. 1A2-1A3
edit : that being with original Rs values (0R47)
if you decrease Rs values , Iq will rise in same amount/percentage
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Have completed another set of Tea's M-2 boards for a Toshiba output version and have a couple of questions.
What is the ideal idss for the Jfets used in M2? I have a set from the store, BL grade,and I have a few sets from High 8 to low 9 idss on hand... and secondly,
As these boards are already assembled with stock values, how much of a problem is NOT changing R11 to .1 R (from 100R) and R13 and R14 to .33R (from .5R) as Zen and others suggested? (See posts #891 and #902) Or just R11 changed and source resistors left at .5?(with Toshiba mosfets)
Thanks,
Russellc
just leave everything as in original
my comments from posts mentioned above were strictly to Generg , regarding Iq increase, in fact , decreasing value of Rs , so decreasing deeneration , so increasing xconductance
Anyone have any feelings about bass output when comparing IRF type mosfets with the Toshibas? Same, less, more? (as far as M2 is concerned.)
Russellc
I believe Generg (Golden Ear ,officially) will have most to say
comparing to him , it seems as I spent several years playing with elephants , while their fave game was farting in general direction of my ears
Well then! Elephants notwithstanding, I am pressing on. I guess I will use the 8.8 or 9.3 idss sets, I assume the store set of Jfets I have, which are BL could be within spec, yet over 10 idss, right? Thinking BL goes up to 12? I would like to try the store set, all I have used on previous builds were Toshiba J fets, but alas, supplies dwindle!
Russellc
Russellc
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