Aleph J illustrated build guide

[brunk]

Ok, cool. Last time I checked (about 2 weeks ago) there were none available, so that's excellent they have all grades. So looks like you'll want B or C grade.

When I said evaluate - batch processing for high spec devices in semiconductor manufacturing is not easy. It just takes time to analyze results, and get the control variables in line to ensure wafer yields are sufficient to make the devices a viable item.

OK I see. Thanks for the info

 

[soundslave]

AJ problems

So if I have a bad power MOSFET do I need to replace 2 or all 4 on that side?

Bob

 

[Danger Mouse]

normaly replacing the 2 which are paired/matched should be ok.

if you have a matched quad for the channel and want a matched quad again then all 4

 

[Seavan]

I started building Aleph J and I am coming close to powering things up. Does it make sense to test the amp before connecting the power MOSFETs?

 

[Zen Mod]

not really

 

[Danger Mouse]

So if I have a bad power MOSFET do I need to replace 2 or all 4 on that side?

Bob

...and i forget one possibility
you could also get 1 mosfet with the right VGS, that fits to the rest that works

 

[soundslave]

I'll need a pair as Q7 and Q8 are both reading bad

 

[soundslave]

Matched MOSFETS

Anyone know where I can buy a matched set of 240's?

 

[didiet78]

search user h_a

 

[6L6]

Also try buzzforb. I've used both guys, they are great! Hannes, (h_a) may have complete transistor kits as well.

 

[brunk]

Also try buzzforb. I've used both guys, they are great! Hannes, (h_a) may have complete transistor kits as well.

Do the MOSFETs require matching for the Aleph J?

 

[6L6]

Yes.

However, you only need match the Mosfets that share current - Meaning you may use a pair that has the same Vgs for the Current source fets (Q5, Q6) and a pair that has a different Vgs for the power output (Q7, Q8).

Yes, a matched Quad per channel, or a matched Octet for a stereo amp is more convenient, it isn't necessary.

 

[brunk]

Yes.

However, you only need match the Mosfets that share current - Meaning you may use a pair that has the same Vgs for the Current source fets (Q5, Q6) and a pair that has a different Vgs for the power output (Q7, Q8).

Yes, a matched Quad per channel, or a matched Octet for a stereo amp is more convenient, it isn't necessary.

OK thanks. I'm assuming the same goes for F4 too?

 

[6L6]

Yes, the N must match the N, and the P match the P, but no need to match N to the P.

 

[brunk]

Yes, the N must match the N, and the P match the P, but no need to match N to the P.

Thanks again

 

[soundslave]

Buzzforb is out of them.

 

[brunk]

Buzzforb is out of them.

Bummer. If you can let me know where you're able to source them, I would appreciate it

 

[soundslave]

Will do

 

[Bones13]

I can only encourage you all to try the Aleph J in full balanced mode. - Wow.
My blue jeans cables arrived finally.

 

[Seavan]

Can you help me with what input I should ground for RCA? Is it IN- that goes to ground and IN+ is an actual input? Thank you!