weird
When building my aleph5 mono's 2 years back i placed 22.1k on R17 instead of 221k. My amps sounden great but never got warm. Today i found that mistake and changed the resistor to 200k. Now my amps do warm up, not sure yet how much playing time now is 20 min. And also the 25w resistors in my psu heat up, they never got above ambient and now are at 110c bit high for my taste.
Still the amps do seem to sound better.
I have the feeling that what i did and notice here is the opposite of what should have happened.
When building my aleph5 mono's 2 years back i placed 22.1k on R17 instead of 221k. My amps sounden great but never got warm. Today i found that mistake and changed the resistor to 200k. Now my amps do warm up, not sure yet how much playing time now is 20 min. And also the 25w resistors in my psu heat up, they never got above ambient and now are at 110c bit high for my taste.
Still the amps do seem to sound better.
I have the feeling that what i did and notice here is the opposite of what should have happened.
I asked , wasn't judging
what's voltage across (any of them ) output source resistor ?
probably easiest to measure at negative PSU rail side
Indeed it is a crc psu. 25w 2.2ohm resistors as was zen mods advice. They level out at 112c without any heatsink.
My speakers. 8ohm Hepta cr-lux.
Transistor temp after 3 hours level at 56c
Heatsink at the top is at 48c.
Dc offset is still around 20mv
Sound is perfect only there seems to be more bass, bit to much for my speakers.
I realy do not understand why my amp heats up when doing the opposite of what is advissed.
My speakers. 8ohm Hepta cr-lux.
Transistor temp after 3 hours level at 56c
Heatsink at the top is at 48c.
Dc offset is still around 20mv
Sound is perfect only there seems to be more bass, bit to much for my speakers.
I realy do not understand why my amp heats up when doing the opposite of what is advissed.
I am not worried about the temp, just surprissed that....
I practicly jumpered R17 to start with and the amp stayed cold, now with 200k in place it heats up.
This whole thread tell's it the other way around.
I would need more heatsinking with a lower resitance while i need more heatsinking with a high resistance in my R17 location. R17 on the KK aleph5 board is R19 in the original.
I practicly jumpered R17 to start with and the amp stayed cold, now with 200k in place it heats up.
This whole thread tell's it the other way around.
I would need more heatsinking with a lower resitance while i need more heatsinking with a high resistance in my R17 location. R17 on the KK aleph5 board is R19 in the original.
You need 0-5 amp DC Meter. Just insert in series with positive rail feeding one channel to make reading. You could substitute 250k ten turn pot in there and set it exactly. Larger meters generally require a shunt and separate meter. You can also use a power meter but this is not as accurate because you are also including the transformer. As long as you have sufficient capacitors you should yank the resistor. I have tried CRC and CLC supply with Aleph 30 and makes no audible difference!
Mark
Mark
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ZM's advice couldn't be 2R2 for CRC , only 0R22
that's just 10 times smaller resistance ....... and exactly 10 times lesser dissipation on them
everything is as is predicted
read what's written in pdf I attached few posts above and you'll see
jumpered means short , which means 0 Ohms ; 221K is indeed opposite direction , and logical - rising that value results in higher Iq
that's why when you remove it , you'll get maximal Iq , possible with mounted source resistors
so , as I'm used to say every time when I'm not understanding something - major short circuit is between headphones , not in circuit
@mark. Thnx i'll try that tommorow.
@zen mod. Yes sorry. You are right. It was 0.22ohm.
must be cristmass stress making me mix up my numbers.
Your explination sounds logical.
At this momente i turned the 200k pots down to 175k temp is still the same but the bass is better than at 200k.
i'll mess around a bit tommorow.
@zen mod. Yes sorry. You are right. It was 0.22ohm.
must be cristmass stress making me mix up my numbers.
Your explination sounds logical.
At this momente i turned the 200k pots down to 175k temp is still the same but the bass is better than at 200k.
i'll mess around a bit tommorow.
@mark.
My psu voltage was prety high so zen suggested that i put in a 0.22 ohm resistor at 25w to make sure i would not blow up my amps. And for 1.50euro per resistor i am not one to complain.
So you may be right in saying you can not hear the difference, i do not know, but i am not taking them out for now.
My psu voltage was prety high so zen suggested that i put in a 0.22 ohm resistor at 25w to make sure i would not blow up my amps. And for 1.50euro per resistor i am not one to complain.
So you may be right in saying you can not hear the difference, i do not know, but i am not taking them out for now.
Seems like the right time for my question.
A PSU which have +/-35V, a 600VA torroid and a capacitance of 132000µF -only C- per Rail (Total 264000µF) will this work?
I`ve read somewhere with only C the current will be pretty high at Startup. And i dont want to blow up something (rectifiers, fuses or even maybe the torroid)
I also read somewhere, with CRC current spikes will be not such a big problem.
I ask because i also want to make my aleph60 clone better than stock
so ive nearly doubled the capacitance.
Replaced 10000µF caps in stock with 22000µF in clone
I would prefer only C so i could make an easy PCB for PSU.
But will the Hardware survive this? dont know how estimate?
And don`t want to make the pcbs twice if only C is suboptimal.
thanks for your advice
A PSU which have +/-35V, a 600VA torroid and a capacitance of 132000µF -only C- per Rail (Total 264000µF) will this work?
I`ve read somewhere with only C the current will be pretty high at Startup. And i dont want to blow up something (rectifiers, fuses or even maybe the torroid)
I also read somewhere, with CRC current spikes will be not such a big problem.
I ask because i also want to make my aleph60 clone better than stock
so ive nearly doubled the capacitance.
Replaced 10000µF caps in stock with 22000µF in clone
I would prefer only C so i could make an easy PCB for PSU.
But will the Hardware survive this? dont know how estimate?
And don`t want to make the pcbs twice if only C is suboptimal.
thanks for your advice
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