Aleph-X builder's thread.

the aleph x is gonna be my first class a hi fi amp.
im a bit worried, because i never built an amp of such quality.

1. what's the input and output impedance?

2. what transistors need heatsinking, and what can be done?

3. if i put the psu in the main box will it hum?
should i take it out to a different box, or will a metal shield connected to chasis be enough?

4. any of you have a psu design? or perhaps any idea whats the current needed to run it?

as u can see, i need some assistance.

all help is welcome.
 
Help for setup the 3 POT's in Aleph X

Dear fellows tech.

After two days spent in my secret place I have give birth my first Aleph X, original by G.Rollins schematic, It is appreciate if there is anyone that help during a setup.

In a wiki tread there is a lot of informations, but is partially different the setup procedure.

I need to set up the 3 potentiometer's that I have in my amplifier, I have followed more instruction without success.

In annex my first pcb made myself, there is kindly men that help me, which is the right setup for set correctly the 3 pot's.

Which is the right DC value on VR1,2 and VR3?


Thanks in advance for a patient and answer men.

JenaP.

edit by pinkmouse:
moved to AXB thread as it is an appropriate Q for that topic
 
Hi

Another rookie here,
I would like to build my own aleph-x.
And I want to create the pcb by myself.....(because it is cheaper)
Is there anyone can give me gerber file of the pcb layout?
Or I must work on the schematic by myself then convert it to a layout.
I am really worry about if I do the layout by myself, the quality won't be good enough.

Thanks
 
Source resistor rating

I searched, but did not find - maybe bad searcher :(

What is the minimum wattage for source resistors on AX-100?
According to William's spreadsheet, it is not even 1W.
Now why are 3W and even 6W suggested here?
Can I use 3W anyway, cannot get good higher wattage locally?

Another guestion re. cap quality, if I must choose a good place for a HQ cap, must I rather use HQ for C3, C5 or for C1, C6 (on Grey's circuit). I got 4 x Elna Cerafines which I want to use somewhere and 4 Panasonic FC caps. Which will be best suited where (all 220uF, 35V) - stereo amp.

My planned specs:
 

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Re: Source resistor rating

JDeV said:

Can I use 3W anyway, cannot get good higher wattage locally?
3W will do fine, 1W would probably work but will run much hotter all the time. (SOA)

I don't think the mentioned caps are that important unlike C2 and C4.
Any good quality device will do. I would go for 105°C rated ones.
Like everything there could be an audible difference. Try and let us know. ;)

/Hugo
 
i have made an alephx 50watt ;8ohm with the hifizen pcb rev1.
option:
d1a : 1n5239b
q12a :j505
q6a: irfp9610

r2 r3 r5 r6 r40 r42 r43 r41 are 0.20ohm 1% 3watt
r1 r4 r44 r45 are 62ohm 5%

the dc is very good +- 1mv

the pb:
when vr1 and vr3 are in 0 ohm the voltage of r5 and r40 are yet 0.450 volt
why?
further more the voltage of r2r3 and r42r43 are 0 volt??
is it normal?


thank you
 
Simple Speaker Protection for AX

While the purist would not want any relays in the signal path (me inclusive), many might just want to have some protection when testing a prototype.

Most circuits on the web are meant for single sided amps (i.e. not differential). Of course you can build two of those to protect each side of a diff amp like Aleph X. But this is what I built, which is very simple and works fine (thoroughly tested). It will trip the relay at about 1.5 to 3 V. Of course you can play around with zener values or amplification factor of the diff pair, etc. to suit you taste. You could also drive a much larger relay with a darlington. The beauty is that the relay is driven by a current source, so you don't have to be too bothered about supply voltages. Just watch dissipations.

I built it p2p, simple enough.

Photo too large to attach (160kB), and I don't have a photo editor at home to compress. Unless someone else can help.


Patrick
 

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