For my peace of mind it is worth it but is it technically?
https://www.mouser.se/datasheet/2/427/mra-1762534.pdf
A fun experiment would be to build one based on rational decisions (as cheap as possible but no cheaper) and another based on emotional(?) part-selection (as high grade as possible but... uhm), hide them into identical chassis and compare them, blind of course.
The nasty mind would then insist to sell the loser without looking which one it was [emoji83]
d.
In my experience, throwing lots of money at boutique audiophile parts is a fantastic idea if your goal is emptying out your wallet faster. I'm not convinced it adds anything to the sound quality.
YMMV
YMMV
Well noted 6L6!
If we are talking resistors can some one help me and point out which are the more important resistors IE that are part of the direct signal pass. I guess R1 is very important since it is in direct path and in the low line end. R2 might be very important as well or?
Others that are key? R16 to R21 or?
If we are talking resistors can some one help me and point out which are the more important resistors IE that are part of the direct signal pass. I guess R1 is very important since it is in direct path and in the low line end. R2 might be very important as well or?
Others that are key? R16 to R21 or?
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before giving you an advice, just say up to which level of Audiophoolery you want me to go?
Sky is the Limit!!

Sky is the Limit!!

Ha ha yes the sky is the limit for us audio nerds.before giving you an advice, just say up to which level of Audiophoolery you want me to go?
Sky is the Limit!!
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I want to do it well and build it as good as I possible can. But put money where in counts. That is why I am looking for your expert advice. Give it a shot Mr Zen and lets see if we can align our audiophoolery moons.
use MP (metal plate, those white flat ones) series for source resistors
or to go wild, use Isabellenhütte ones
trimpots strictly multiturn Bourns, most expensive you can find in adequate form factor
R1,2,3,4 - use Dale non magnetic ones, or go wild and think Shinkoh and .....ah, wtf! just look at this page and use most expensive ones: Resistors | Hifi Collective
for mosfet gate resistors only 1/4W Allen Bradley Carbon Composite ones are Kosher enough to be even put in the mouth of proper Audiophi/oo/l/e
and yes - elcos - industrail quality is either Pana or Elna or Rubycon; but Kosher is nothing else than Black Gate
you'll even gladly suffer 5 months needed that that Drek even start to conduct something and sing

or to go wild, use Isabellenhütte ones
trimpots strictly multiturn Bourns, most expensive you can find in adequate form factor
R1,2,3,4 - use Dale non magnetic ones, or go wild and think Shinkoh and .....ah, wtf! just look at this page and use most expensive ones: Resistors | Hifi Collective
for mosfet gate resistors only 1/4W Allen Bradley Carbon Composite ones are Kosher enough to be even put in the mouth of proper Audiophi/oo/l/e
and yes - elcos - industrail quality is either Pana or Elna or Rubycon; but Kosher is nothing else than Black Gate
you'll even gladly suffer 5 months needed that that Drek even start to conduct something and sing

Mr Zen the man. I guess I got what I asked for. Fantastic🙂. Ok i will reveal now how little I know
Which R numbers are are the source resistors?
Which R numbers are are the mosfet gate resistors?
use MP (metal plate, those white flat ones) series for source resistors
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Which R numbers are are the source resistors?
for mosfet gate resistors only 1/4W Allen Bradley Carbon Composite ones are Kosher enough to be even put in the mouth of proper Audiophi/oo/l/e
![]()
Which R numbers are are the mosfet gate resistors?
Lightning fast!!!!!
Gate resistors. No sound signal go through these resistors or?
Resistors on source or drain side have sound signal or?
Gate resistors. No sound signal go through these resistors or?
Resistors on source or drain side have sound signal or?
use MP (metal plate, those white flat ones) series for source resistors
or to go wild, use Isabellenhütte ones
trimpots strictly multiturn Bourns, most expensive you can find in adequate form factor
R1,2,3,4 - use Dale non magnetic ones, or go wild and think Shinkoh and .....ah, wtf! just look at this page and use most expensive ones: Resistors | Hifi Collective
for mosfet gate resistors only 1/4W Allen Bradley Carbon Composite ones are Kosher enough to be even put in the mouth of proper Audiophi/oo/l/e
and yes - elcos - industrail quality is either Pana or Elna or Rubycon; but Kosher is nothing else than Black Gate
you'll even gladly suffer 5 months needed that that Drek even start to conduct something and sing
![]()
Lightning fast!!!!!
Gate resistors. No sound signal go through these resistors or?
Resistors on source or drain side have sound signal or?
I have tried my best to rank the resistors regarding which ones are important to the sound.
Please add your opinion or tell me where I go wrong below. Ranking 1-5 where 5 is important:
• R1+R2.........5
• R3+R4.........4
• R5-R9......... 1
• R10-R15......2
• R16-R21......3
• R22-R25......1
The gate resistors pass the sound signal to the FETs' gates, but only very little current passes (practically only charging and discharging the gate capacity, that's what makes mosfets so special as compared to bipolar transistors). In my opinion, RN60 resistors are already overkill here, so just about right.
The source resistors each pass a share of the current that is going through the speaker voice coil. Bulk foil resistors like the Fukushima MPC are probably as far as you want to go. I wouldn't use Mills MRA in that position, not much to gain really.
Concerning trimpots, Vishay has these bulk foil potentiometers:
Y40535K00000K0L Vishay Precision Group Foil Resistors | Mouser Osterreich
They would no doubt be a complete waste in that position, just use Bourns 3269 and be done with it.
The source resistors each pass a share of the current that is going through the speaker voice coil. Bulk foil resistors like the Fukushima MPC are probably as far as you want to go. I wouldn't use Mills MRA in that position, not much to gain really.
Concerning trimpots, Vishay has these bulk foil potentiometers:
Y40535K00000K0L Vishay Precision Group Foil Resistors | Mouser Osterreich
They would no doubt be a complete waste in that position, just use Bourns 3269 and be done with it.
The gate resistors pass the sound signal to the FETs' gates, but only very little current passes (practically only charging and discharging the gate capacity, that's what makes mosfets so special as compared to bipolar transistors). In my opinion, RN60 resistors are already overkill here, so just about right.
The source resistors each pass a share of the current that is going through the speaker voice coil. Bulk foil resistors like the Fukushima MPC are probably as far as you want to go. I wouldn't use Mills MRA in that position, not much to gain really.
Concerning trimpots, Vishay has these bulk foil potentiometers:
Y40535K00000K0L Vishay Precision Group Foil Resistors | Mouser Osterreich
They would no doubt be a complete waste in that position, just use Bourns 3269 and be done with it.
Thanks a lot Rodeodave!
Can you comment on my ranking of importance ?
• R1+R2.........5
• R3+R4.........4
• R5-R9......... 1
• R10-R15......2
• R16-R21......3
• R22-R25......1
They are all important.
Also, in my experience and opinion, there is no better resistor for our purposes than the Vishay/Dale RN series.
Also, in my experience and opinion, there is no better resistor for our purposes than the Vishay/Dale RN series.
I do not know if I agree. But please no fight. I am a newbei.
But all I know is that resistor noice quality is more important:
For high resistor values.
For resistors with higher current
Early in the signal path
In the signal path
The ground input
So can all then have the same importance?
Cheers.
But all I know is that resistor noice quality is more important:
For high resistor values.
For resistors with higher current
Early in the signal path
In the signal path
The ground input
So can all then have the same importance?
Cheers.
Spending more money on resistors will absolutely cost more money. I don't think it will do much else. 🙂
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just use good quality resistors, means good engineering grade (not audiophool) which in my book means a reputable brand sourced not from ebay-china, film type (thin metal film is a good place to start) and plenty of derating (e.g. use 1/2W for small signal rather than 1/8W). Source resistors can be non-inductive wire wound.
Noise will be dominated by Mr. Johnson so long as you avoid known krap techology like old bulk carbon-comp and possibly other thick film types
Noise will be dominated by Mr. Johnson so long as you avoid known krap techology like old bulk carbon-comp and possibly other thick film types
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I used TE Connectivity, .01% tolerance on mine for no reason other than it wasn’t expensive to do so
Noise will be dominated by Mr. Johnson so long as you avoid known krap techology like old bulk carbon-comp
The scientific community has decided upon a new and better name for what used to be called Johnson Noise. Behold:
Johnson–Nyquist noise - Wikipedia
... which is a shame because now you can't tell somebody to "take your noisy Johnson somewhere else, please!"
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