Aleph J illustrated build guide

6L6

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Hello I have completed my aleph J and I tried it with a backup system: because when I turn it off ul feel "bump" on the speakers?
solve the problem with a soft start?

The Bump is normal on shutdown.

The soft start will not change the speaker 'bump'. However, the DC protector board will cut out the speakers when the DC imbalance is present on the outputs.

Both the DC protections and the soft start are sold together - New Soft Start & Speaker Turn-On Delay and DC Protector Boards (Set of 2 boards) - Circuit Boards


I built the power supply with a breadboard pcb but I do not trust a lot:
where can I buy the pcb power as that used by 6L6?
thanks for the answers

The poser supply PCB in this guide is no longer made, it has been replaced with this board - Universal PSU V3 - Circuit Boards

Build guide here - http://www.diyaudio.com/forums/powe...circuit-board-v3-illustrated-build-guide.html
 
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Joined 2003
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nope

me Padawan

Manu Yoda

;)

Papa Force

funny one
 

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Hello, I tried the amp with my main system: never heard of a similar detail and transparency even though I had already 'a chain Naim with external power supplies.
I just have a doubt about the bass control, seem a little less controlled than the Naim.
may depend on the bias a little low around 360mv?
After 2 hours the temperature of the heat sink is not high you can safely rest your hand on for a long time. I think it's around 40 or 45 degrees
I used a 40cm deep 4u

do you think you can improve the bass control?
thanks
 
Official Court Jester
Joined 2003
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matter of Iq and Aleph AC gain ........ and speakers , in general
I'm always saying that , for full potential , with A class amp one need to have dynamically not challenged speakers

not just efficient , but also sensitive ..... sorta old school speaks - big cones , strong motors , but not overly powerful (which demands stronger/heavier/firmer everything)

so , yours are ?
 
my speakers are the Ekta Grande I've built and designed by Troels Gravesen
and the towers are three-way speakers with dual woofers and Scan Speak their sensitivity is around 89db,
their main feature is the fullness and balance of the sound
however, the aleph j does his duty by giving to the mid and high definition un'ariosità that I had not yet heard
I saw that someone has adjusted the bias to 0.5 V: more thing to the amplifier with this set up?
thanks
max
 
Official Court Jester
Joined 2003
Paid Member
my friend is having Ekta's ;
knowing his experience with several Papamps , I believe him when he said that he prefer amps with more control then weaker Alephs can give

F5 , M2 , if staying in same power range

going up , there is plenty of option (PP BA iterations , X variations etc. )

or just make second identical J , and run channels in parallel ;)
 
Had some time to look at my amp today, the left channel is still not working. The offset will not zero and after setting for a while the output goes to 6-7 volts on its own. Checked voltages to ground and found that most of the voltages on the positive rail fluctuate by several hundred mv. The volts at the diode and R8 did not however. At the point at R27 where you can install a fixed resistor instead of the variable on the side that connects to R15 the voltage is all over from neg to pos and does so at such a fast rate that the meter has a hard time keeping up. Could it be one of the caps? :confused:
 
The thermistor in the mains connection is a soft start. You can replace it with another soft start if you wish. I prefer to use the thermistor in place of the resistors usually found in soft starts. If the relay bypassing the resistance fails, the thermistor resistance goes low and you won't have burning parts. Even a class AB amp will still work (with a little more fluctuation in the voltage the transformer sees.)