Aleph J Schematic

[Zen Mod]

use xformer , if you ask me - by Brave Mickey recipe

take proven one , meaning especially on proven secondary loading , to have it linear 20-20K

 

[schultzsch]

being a dsd capable dac the transformer needs to be linear till 50K at least because the speakers are capable of 50khz too.

thanks again, you made my day!

 

[schultzsch]

If I have C1 shorted it`s ok to connect the amp balanced?

 

[schultzsch]

I ask I answer, it works but it has hum because I didn`t connected the ground so will remain in se for a while!

 

[6L6]

If I have C1 shorted it`s ok to connect the amp balanced?

Leave C1 in place and connect it balanced.

 

[craigtone]

Stupid question ... I have the equipment in my sig. Neko is balanced out (currently using XLR to RCA cable). Would I benefit from converting the Pearl2, Mez and Alpeh J to balanced? I assume just + to +, - to - and shield to chassis?

 

[6L6]

Well, you'd need a BAL to SE converter, either a transformer or some active circuit, it's not as simple as changing the connections.

 

[schultzsch]

Hello 6L6 and nice to see you again!

I'll give it a try tomorrow and report back cause now I've put in charge the 3x 12v 30amp(each) lipos that power up my dac and iv stage and this takes a while...
So tomorrow will try with c1 in the circuit but with ground connected only on the amp side.

 

[schultzsch]

Ups!

Don`t know why I was thinking that c1 was shorted because it wasn`t. 🙂

So nothing to change...

 

[2 picoDumbs]

Hello Papa
Refering to your Aleph J schematic, R27 is connected directly to the gate of Q5 and Q6.
Is it possible that R27 is intended to be connected between the junction of R25, R26 and C2? If connected this way it results in 2A bias and seems to operate somewhat better into low impedance loads (from memory).
The way you have it connected results in approximately 2.6A of static bias (a little high).
I know the issue of high bias was addressed by members with trimpots, but it was applied somewhat differently.
It seems to me R27 should have been connected between R25, R26, and C2

I was meant to ask this question approximately 8 years ago. Back then I was a scaredy cat. 😀

 

[Zen Mod]

I asked

Pa replied ........ naah , it's not so important

meaning - bugger off , who cares for little details already chewed zillion times

 

[schultzsch]

I have built some 2 terminal ccs's to bias the ltp of my each j.
I am using r8 in series with the ccs, from positive first I have r8 then the ccs.
I have instaled the ccs in one channel, set it up for 14 ma bias for the ltp and is all working up and biasing correctly.
Does r8 position(first or after ccs) and value matter?
Having 14v drop acros r8 I am considering to lower its value to 500ohm. Is this recommended?

 

[2 picoDumbs]

Position of R8 is non-negotiable. Needs to be between emitter and positive rail.

If you already have 14mA, dropping to 500Ohms is a bad idea.

 

[schultzsch]

I have replaced the original ccs with a 2 terminal ccs so I am not using anymore c4,z1,q2 and r5, the ccs is connected in place of ce pins of ztx550. Now the ltp bias is similar to ba1 front end only that I use something else as ccs insted of k170.

I have reworked also the second channel 🙂

 

[2 picoDumbs]

Show me the schematic of your ccs.

 

[schultzsch]

Something like this

 

[2 picoDumbs]

Ok just checked BA1 CCS.
You could drop the 1k resistor to 700 Ohms if you wanted.

EDIT: Completely forget this. I thought you were using a jfet like in BA1

 

[2 picoDumbs]

Something like this

So you are using Rs around 180 Ohms? Or trimpot there?

 

[schultzsch]

Trimpot

 

[2 picoDumbs]

I'm guessing the 1k resistor you are referring to is placed on the positive side of the TL431,
If so I would not change to a lower value. Anything between 1k and 4k is quite suitable.