I used Nichicon FG or KW - one of their audio grade caps.
Those caps are rated at 85°C.
Should one use capacitors rated at 105°C?
It will get quite "warm" inside an F6.
Btw. did someone measure the temperature of the caps in an actual build?
Ulf
I think I'll stick with Panasonic FC-series caps for C1 and C2 since I have some left over from a BA-3 build.
Hello Ammell,
Why dont you try the 5 watt mills at partsconnexion in Canada. I use thjem all the time when i need high wattage resistors. If i ever build a Nelson Pass amp i would certainly go for these. They are 20ppm maybe that is of no importance but they sound very good.
Just did replace some 3 watt metal oxide resistors in my Curcio Dac by these and they are way better.
Also remember using them in a Daniel preamp some decades ago.
They are a bit more expensive than the ones usually applied but you should try them asnd some other people should replace the ones thjey are using by these ones too.
Greetings, Eduard
Are you referring to these Mills resistors?
Mills MRA-5 Resistors
Thanks...
Hello Ammel,
yes,These are the ones. There is also a 12 watt model but if the original ones are 3 watt 5 watt will be enough i guess. Mount them at some distance from the board so there can be some airflow. Of course the surrounding temperature can be warm in this amp i think. But these resistors can handle some heat just take care they dont heat up sometyhing close by.
greetings, eduard
yes,These are the ones. There is also a 12 watt model but if the original ones are 3 watt 5 watt will be enough i guess. Mount them at some distance from the board so there can be some airflow. Of course the surrounding temperature can be warm in this amp i think. But these resistors can handle some heat just take care they dont heat up sometyhing close by.
greetings, eduard
To those of you with finished F-6 amps, a question. Reading about the commercial F-6 over on the First Watt page, I see that it is comparable to F-5 in one regard, gain....14dB. How is it driving real world speakers of various types? I will be using a BA-3 preamp if that helps...what are you guys finding and with what speakers?
Russellc
Russellc
@ammel68 (an others) - FYI I found mine at Digikey, Panasonic 3 watt ERX/ERG series, same as I'm using for all other 3 watt positions.
ERX-3SJR56 Panasonic Electronic Components | P0.56W-3BK-ND | DigiKey

ERX-3SJR56 Panasonic Electronic Components | P0.56W-3BK-ND | DigiKey

Yes, Digikey has all 3 values of the 3W resistors in Panasonic.
Here are links for the 100 ohm and .47 ohm resistors:
100 ohm: ERG-3SJ101 Panasonic Electronic Components | P100W-3BK-ND | DigiKey
.47 ohm: ERX-3SJR47 Panasonic Electronic Components | P0.47W-3BK-ND | DigiKey
Here are links for the 100 ohm and .47 ohm resistors:
100 ohm: ERG-3SJ101 Panasonic Electronic Components | P100W-3BK-ND | DigiKey
.47 ohm: ERX-3SJR47 Panasonic Electronic Components | P0.47W-3BK-ND | DigiKey
To those of you with finished F-6 amps, a question. Reading about the commercial F-6 over on the First Watt page, I see that it is comparable to F-5 in one regard, gain....14dB. How is it driving real world speakers of various types? I will be using a BA-3 preamp if that helps...what are you guys finding and with what speakers?
Russellc
post 592 may offer some info
Hello Ammel,
First you could get the panasonic and then replace them with mills and tell everybody i was right. Greetings, Eduard
p.s in the photo you can see i did use them
Hi Eduard,
I don't like doing things twice, so I doubt that I'll be experimenting with different brands of resistors.
In addition, if I go with the Mills I would apply the $.53/ea. cost of the Panasonics towards the much more expensive Mills.
post 592 may offer some info
Saw that, not really what I have on hand. What speaker is everyone using with F-6 and how is the gain? About like F-5 in use?
Russellc
Is there anyone on this forum offering matched IRFP240s?
The .56 ohm 3W resistors don't seem to be an easy find.
Will these work?
RS02BR5600FB12 Vishay / Dale | Mouser
Is the blue LED, used along with a 10K ohm limiting resistor, a 3mm or 5mm LED?
Jim, can you or someone please provide a link to the appropriate LED from Mouser?
Thanks...
I noticed on page #1 6L6 said it was for "IRF 420" .......This is a typo for IRF 240? Is this the one? IRFP240PBF Vishay Semiconductors | Mouser
Or this one? not sure why so much more expensive:
http://www.mouser.com/ProductDetail...=sGAEpiMZZMshyDBzk1/Wi5brl1xcCtmLSxVqzQmK/jE=
Or:
http://www.mouser.com/ProductDetail...=sGAEpiMZZMshyDBzk1/Wi5brl1xcCtmLSxVqzQmK/jE=
From under 3 bucks to over 10 bucks, I suppose there is some difference?
Russellc
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I noticed on page #1 6L6 said it was for "IRF 420" .......This is a typo for IRF 240?
It's just a typo.
From under 3 bucks to over 10 bucks, I suppose there is some difference?
Russellc
The expensive one is legacy, not ROHS compliant.
The expensive one is legacy, not ROHS compliant.
Given the price difference, is there some performance advantage, or is it "this is the cost of using non compliant? Seems like they would want rid of them...
If they must cost more because of that status, seems they would never sell. Now if there is a performance difference, I get it.
Russellc
Nope. The PCB+ Jensen will be the only thing offered for however long it takes to get more PCB made and shipped. (Usually more than 6 weeks)
Bummer, I already have CineMag, so unless someone wants to buy mine, I'll have to wait again (missed them twice because they came and went so fast). I'm really a tube guy and was going to build as back-up, but turning into a real effort. I wouldn't bother but had a threshold when I was younger, and have a soft spot for Nelson's designs.
The Cinemag don't fit the diyAudio store boards... so you'll need the Jensen regardless.
The F6 is an amazing amp, I'm sure you will be very pleased when it's done.
The F6 is an amazing amp, I'm sure you will be very pleased when it's done.
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