Looks like you were still sleepy, Shaan 😉. The C type specifies the Hfe grade, doesn't it? BC550 (or BC549) is special because it is the low noise one, but Vce is ONLY 45V for BC550 (and only 30V for BC549).
I myself prefer the C1815/A1015 which has Vce of 50V.
I don't know how to "predict/calculate" the maximum supply related to Vce. Ime, transistors rarely see high voltage in an LTP. I hope somebody can explain the possibility of "failure" regarding to the Vce.
If Thimios thinks that +/-35V is maximum for BC550 (Vce=45V) then I will be very happy. I do feel worry sometimes 😀 (I thought I might be lucky because I have never played music too loud in my age).
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Hello Jay.
By C types I meant the 550C/560C pair instead of the 546/556 pair (I know this indication is technically incorrect). But I think we are safe because we have been talking about the 550C/560C pair only and not the 549C/559C pair.
*back to sleepy mode 😀
By C types I meant the 550C/560C pair instead of the 546/556 pair (I know this indication is technically incorrect). But I think we are safe because we have been talking about the 550C/560C pair only and not the 549C/559C pair.
*back to sleepy mode 😀
is vas bias read between the 10ohm resistors?
i built a 20v version, with 12k bias resistors, and with my meter set at mA, i'm only reading 3mA at that location, the vas transistors barely warm to the touch, and the bass is very... feeble.
all other resistors are same as the schematic
i built a 20v version, with 12k bias resistors, and with my meter set at mA, i'm only reading 3mA at that location, the vas transistors barely warm to the touch, and the bass is very... feeble.
all other resistors are same as the schematic
sorry, i figured it out but not before i decided to stop being lazy. 🙁
so my build is correct, bias settings are right, but the sound i get at 20v supply is not nearly as good as 35v. i was hoping to scale everything down for higher sensitivity speakers- lower voltage, lower heat, and greater stability while maintaining awesome sound, but i guess there's sweet spot for everything?
as it is, my 20v version has weaker bass and transients are not as snappy. i'd like to know if making the output mosfets work harder will improve the sound.
sigh.... i still dont think im reading the vas bias right.. please help. xD 🙁
so my build is correct, bias settings are right, but the sound i get at 20v supply is not nearly as good as 35v. i was hoping to scale everything down for higher sensitivity speakers- lower voltage, lower heat, and greater stability while maintaining awesome sound, but i guess there's sweet spot for everything?
as it is, my 20v version has weaker bass and transients are not as snappy. i'd like to know if making the output mosfets work harder will improve the sound.
sigh.... i still dont think im reading the vas bias right.. please help. xD 🙁
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Hi donovas.
Set your meter in the mV range not mA. When you read 100mV around the 10ohm VAS resistors VAS bias will be 10mA.
Also you need to decrease the 15K resistors to something like 8k2 or 10k for 10mA VAS bias at that PS voltage.
Set your meter in the mV range not mA. When you read 100mV around the 10ohm VAS resistors VAS bias will be 10mA.
Also you need to decrease the 15K resistors to something like 8k2 or 10k for 10mA VAS bias at that PS voltage.
PeeCeeBee in da black box
Swap few of el cheapo 10% tolerance Rs in to metal film, silvered mica 220pF and add speakers protect with delay circuit.
Be nice in there "little baby monster" 🙂
It sings so nice... love it !
Swap few of el cheapo 10% tolerance Rs in to metal film, silvered mica 220pF and add speakers protect with delay circuit.
Be nice in there "little baby monster" 🙂
It sings so nice... love it !
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hi Shaan,..
thanks but sorry for ugly cables layout, coz for personal uses not commercial 😀
can i use lm4562 based preamp ? or have to go to DOZ preamp ? or other discrete based preamp?
thanks but sorry for ugly cables layout, coz for personal uses not commercial 😀
can i use lm4562 based preamp ? or have to go to DOZ preamp ? or other discrete based preamp?
Nice case, was that an audio case or a repurposed 1U rack mount computer case? Anyhow, where did you get the case?
Hi Guzz,
PM me if you need BC550C + BC560C
I have hundred's of them , also A1381E+C3503E if you want to try 🙂
& prepare to hear the different ... 😎
You also can inbox me, I think you know JW 😀
Long time I don't plug in the soldering iron, still have some PeeCeeBee's PCB laying around
V2, I think I must try it 💖
Best Regards
John
Hi Bli 😉
Of coz i know who you are
most diyers in our country should know you 😀
"A1381E+C3503E & BC550C/560C" tell me a bit bout the magic if i use them,
already purchased 550C/560C from ebay, but haven't arrive yet. If they are not good enough ( counterfeit ) i'll contact you Bli
V1.1 already suit me, other reason this FET also hard to find here, i bought a pair of J162 on local store then have to purchased K1058 from Jakarta.
J162 are toshiba & K1058 are reneseas 😕 weird huh
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Toshiba does not manufacture lat FETs. Should be Hitachi. Pl see if got counterfeits.
Ref
Prasi
Hi Shaan,
it is quite a long time I not post here.
It's always a great 😎
more people should try it with tested layout, like yours 🙂
wrong layout can give a poor result.
here the link : Joshvi
I have bought it twice from Joshvi 😀
Best Regards
John
it is quite a long time I not post here.
Great!!!
It's always a great 😎
more people should try it with tested layout, like yours 🙂
wrong layout can give a poor result.
I found your friend in India sell these transistor for VAS ...
Time to get some of these myself!
here the link : Joshvi
I have bought it twice from Joshvi 😀
Best Regards
John
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