Aleph-L Preamp

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Is there ANY chance of getting some info on the Aleph-L preamp? I have searched high and low to no avail, just a lot of intriguing references. I am specifically interested in the passive/active version, v1.2 I believe. How was it done?, crossover issues? It seems pretty idea in theory in this age of hot output CDP's (my Njoe Tjoeb 4000) and so-so tuners (NAD 1700).

I have built the BOZ and like it a lot. It's feeding a Tubelab SE 300B tube amp that gives me a great sound through some single driver Decware HDT's. My intention is to A-B compare the Tubelab with a V9 whenever some boards come available but in the meantime I would like to build an Aleph-L. Any help is GREATLY appreciated.:cool:
 
Halo,

How the passive/active version is done you can see in service manual. If you don't have one drop me an e-mail and I will mail it to you.

I have built BOZ, BSOZ, both Aleph L and Both Aleph P.

The best sounding of them in my opinion are both Aleph P (I like 1.0 better) and the second would be Aleph L all time active version. I didn't like passive/active version and didn't find it interesting.

Aleph L all time active version is a very good sounding pramplifier, where it looses to Alpeh P is some refinement of frequency extremes (bass and highs), but it has much higher gain so if you need a high gain Aleph L is the way to go.

All my observations are based on my copies of those designs, originals or some other's versions may vary. But I must say I used very similar or exactly the same parts (resistors, capacitors..) and enclosures to evaluate the sonic diffrances between them.

Bartek
 
Believe or not . . . Love of my ears is P1.0 . . .

:) :) :) :) :)

Try to power it from batteries. Makes wonders to the sound.

I power it from ten 6V 2Ah batteries connected in series. Bare circuit, ommiting regulator.

6 Volt batteries becouse a take 18V reference voltage out of first three of them.

What I still haven't tried is instead feeding the bare gain circuit out of 60 Volts trying to feed the circuit with regulator out of bank of 80 Volt batteries.

Bartek
 
Whats the fuzz about the P - I really must build it now that you all sing its praises - at least as a project to fill out the time before somebody makes a nice pcb and kit for the UGS-clone... :)

I see that it uses really big FETs in the gainstage - the irf244 - would the IRFP240 be a good replacement as it is in the powerstages of the alephs ?

And what about the ref. voltage @ 18 volts that charges the mosfets' gates - is this the secret an where the "dog is buried" ?

Cheers !
Buhl
 
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