DIY Aleph 2 Monoblocks

[Guido]

This thread will follow my DIY Aleph 2 project.
It started yesterday with the arrival of the first components in a 28kg package:
2x 1000VA torodial
1x 0,18K/W heatsink cabinet
plus some small parts

All the remaining parts:
1x 0,18K/W heatsink cabinet
PCB's plus components
8x 66000 uF caps
etc. Parts
are expected to show up today.

First pics will follow.........

[northwood]

Congratulations!!!
I'm waiting ur news.
There r several aleph fans in this website.
:applaud:

[Guido]

OK, here are the first pics. I just unpacked everything and checked all parts.

All parts where ordered as a kit from www.rt-audio.nl (http://www.rt-audio.nl) Unfortunately the site is only in dutch but Rick speaks english.
The shop owner, Rick is a very kind person and helped me a lot. Ordering the complete kit saves you a lot of trouble.
Especially interesting are the cabinets he sell. Mine have huge 0.18K/W heatsinks. Frontplate is 10mm brushed Aluminium!
The caps are coke can size.

[Guido]

ALL parts are included

[JBLnsince1959]

Way cool...we'll be watching...let us know how it goes:applaud:

[DavidF]

This thread will follow my DIY Aleph 2 project.
It started yesterday with the arrival of the first components in a 28kg package:
2x 1000VA torodial
1x 0,18K/W heatsink cabinet
plus some small parts

All the remaining parts:
1x 0,18K/W heatsink cabinet
PCB's plus components
8x 66000 uF caps
etc. Parts
are expected to show up today.

First pics will follow.........

Is this to be two mono-chassis, Guido?
DavidF

[Ian Mackenzie]

Nice project

Ian

[LowPhreak]

Very cool, Guido. I've always wanted to pick up one of the Pass projects myself.

Tho' I'd rather have a couple of the X-series amps already built and waiting on the front door when I got home. :bouncy:

Meanwhile, you could send me those blue Coke cans for "recycle" when you're done with 'em. :applaud:

[hjames]

I've heard that the Pass systems are really clean and sweet sounding - but what kind of numbers does this particular model have? W/ch?

From the look of the parts, it looks really well done!

So, if I may be so gauche - how much does a kit like this cost?


OK, here are the first pics. I just unpacked everything and checked all parts.

All parts where ordered as a kit from www.rt-audio.nl (http://www.rt-audio.nl) Unfortunately the site is only in dutch but Rick speaks english.
The shop owner, Rick is a very kind person and helped me a lot. Ordering the complete kit saves you a lot of trouble.
Especially interesting are the cabinets he sell. Mine have huge 0.18K/W heatsinks. Frontplate is 10mm brushed Aluminium!
The caps are coke can size.

[Ian Mackenzie]

I've heard that the Pass systems are really clean and sweet sounding - but what kind of numbers does this particular model have? W/ch?

From the look of the parts, it looks really well done!

So, if I may be so gauche - how much does a kit like this cost?

http://www.passlabs.com/downloads/old%20product/a2man.pdf

SPECIFICATIONS
Gain 20 dB balanced, 20 or 26 dB balanced
Freq. Response - 0.5 dB at 2 Hz, -2 dB at 100 KHz
Power Output 100 watts/ch 8 ohms
200 watts/ch 4 ohms
Maximum Output 40 volts, 10 amps
Distortion (1KHz) 0.5 % @ 100 watts, 8 ohms
1% @ 200 watts, 4 ohms
Input Impedance 10 Kohm unbalanced
25 Kohm balanced differential
Damping factor 100 nominal
Output Noise 600 uV unweighted
DC offset < 100 mv
Power Consumption 300 watts
Temperature 25 degrees C. above ambient
Dimensions 12 " W x 12" D x 10.5" H
Shipping Weight 60 lb.

[Guido]

Is this to be two mono chasis, Guido?
DavidF

Yes, 2 monos app. 30 kg each :bouncy:

[Guido]

http://www.passlabs.com/downloads/old%20product/a2man.pdf

SPECIFICATIONS
Gain 20 dB balanced, 20 or 26 dB balanced
Freq. Response - 0.5 dB at 2 Hz, -2 dB at 100 KHz
Power Output 100 watts/ch 8 ohms
200 watts/ch 4 ohms
Maximum Output 40 volts, 10 amps
Distortion (1KHz) 0.5 % @ 100 watts, 8 ohms
1% @ 200 watts, 4 ohms
Input Impedance 10 Kohm unbalanced
25 Kohm balanced differential
Damping factor 100 nominal
Output Noise 600 uV unweighted
DC offset < 100 mv
Power Consumption 300 watts
Temperature 25 degrees C. above ambient
Dimensions 12 " W x 12" D x 10.5" H
Shipping Weight 60 lb.

Come on Ian! It's more than this ;)

[Guido]

So, if I may be so gauche - how much does a kit like this cost?

Please contact Rick at [email protected]

[Ian Mackenzie]

I have built a pair as I recall.

Enjoy

[Ian Mackenzie]

There in only one word to describe these my dear...LARGE and they run hot to touch, about 50c.

Cost is somewhere b/n $700-$1000 depending on the chassis and component selection. They go remarkably well with standard parts.

Its an exercise in very conservative engineering. I built an Aleph 3 in 2000, rebuilt to to an Aleph 5 in 2001 ...a good learning curve on machine shop practise along the way. The built an Aleph 2 pair of mono blocks in 2003.

They are fun an they do sound very good.

Ian


I've heard that the Pass systems are really clean and sweet sounding - but what kind of numbers does this particular model have? W/ch?

From the look of the parts, it looks really well done!

So, if I may be so gauche - how much does a kit like this cost?

[Ian Mackenzie]

Very cool, Guido. I've always wanted to pick up one of the Pass projects myself.

Tho' I'd rather have a couple of the X-series amps already built and waiting on the front door when I got home. :bouncy:

Meanwhile, you could send me those blue Coke cans for "recycle" when you're done with 'em. :applaud:

I know wat you mean.

A couple of people have attempted a X diy and apparently it was good.

I now have a factory X250.5. I feel I have been blessed by Pass.

When I get more time I will showcase it on the forums.

Ian

Ian

[Ian Mackenzie]

Guido,

When you get to matching the input pair let me know.

Ian

[Guido]

Guido,

When you get to matching the input pair let me know.

Ian

They are pre-matched IRF9610's. Do you need the values?

[Ian Mackenzie]

That's okay. I was going to offer a suggestion on how to get the best match.

What tolerance?

Ian

[Guido]

I don't know Ricks matching setup. On all 6 9810s is written 67 so I suppose they're matched withn 10mV.

As for the 240s
7 of them show 43
All other show 45
so I suppose they're matched within 0.2V

[LowPhreak]

Ian -

I have yet to hear an X .5 bigger than the 150.5. Guess I should take a :drive: to the Big Apple soon.

Ya know, I wish he'd make a smaller .5 monoblock, like say a X100.5.

[northwood]

ALEPH1.2 MONO
look the left

[LowPhreak]

ALEPH1.2 MONO
look the left

...and I see it's "portable" too! :blink:

[morbo!]

yeah
definatly the coolest kid on the block with that beatbox)
nice work northy

[Guido]

ALEPH1.2 MONO
look the left

Is this your Aleph?

Currently my cabinets are at the metal worker to do the cutouts and drillings professionally. I'm also waiting for the 1000VA 2x37V Transformers to arrive.
Soldering the PCB's will start tomorrow.

Should I use normal solder or 2% silver solder?

[LowPhreak]

Why be stingy at this point? Just use the 2% AG! This is a Pass amp you're doing, right? :scold:

Or you could do away with all of that hassle (and your various JBL iterations) and get a set of Rushmore's. Problem solved! But who's got $40k or so laying around for speakers?

[Ian Mackenzie]

Is this your Aleph?

Currently my cabinets are at the metal worker to do the cutouts and drillings professionally. I'm also waiting for the 1000VA 2x37V Transformers to arrive.
Soldering the PCB's will start tomorrow.

Should I use normal solder or 2% silver solder?

I doubt it matters, the quality of the joint is what matters more. ie these thing get bloody HOT mate!:D . Take your time, cleanliness is a must and use a powerful iron is needed.

Here the Pass gals in production...sweetie pies. The Hug I still remember from K! (2nd from left)

[Guido]

Why be stingy at this point? Just use the 2% AG! This is a Pass amp you're doing, right? :scold:

That's exactly what I'm using.



I doubt it matters, the quality of the joint is what matters more. ie these thing get bloody HOT mate!:D . Take your time, cleanliness is a must and use a powerful iron is needed.


That's a given!

Thanks for the help guys. Yesterday I soldered the 1st mainboard and the 1st constant current board.

I'm still waiting for the right (2x37V) transformers and the 220uF Panasonic FC's to arrive.

[Guido]

Ian,

does it makes sense to bypass the Z5?
If yes, why and with what cap?

Thank you!

[Ian Mackenzie]

I never did, use only a small value 0.1 - 1uf.

It just reduces the zenor noise bandwith.

Ian

[Guido]

The 220uF caps aren't soldered as I'm waiting for the better Panasonic types.

The PCB shows Aleph 4 but is equipped with Aleph 2 parts!

[Ian Mackenzie]

Nice!!:applaud:

[QwertyAccess]

Nice, and about that picture, Perhaps its an Aleph 4 - 2 :)

[Ian Mackenzie]

The differences are primarily the supply rails and bias current.

The Aleph 4 was a stereo chassis and had 50 volt rails, it was optimised for more or less 8 ohm. The Aleph 2 was a mono chassis, had 45 volt rails with more bias current and to put more power into lower impediance loads.

The schematics are otherwise identical.

Ian

[Guido]

Nice, and about that picture, Perhaps its an Aleph 4 - 2 :)

It will be a pure Aleph 2

[Ian Mackenzie]

Have you figured out your layout yet?

Ian

[Guido]

Have you figured out your layout yet?

Ian

Yes!
Unbelievable that you can run into space problems with such a case.

The white pancake is a placeholder for the incoming transformers ;)

[Guido]

Internal rear panel connections.

I damped the rear panels with bitumen (tar) sheets additionally. No pics of this as they are ugly now.

[Guido]

The are nearly finished.
Top and bottom cover not mounted, one blue LED not shining.
BUT THEY PLAY!

I can tell ya. Honestly I do not know how to describe the sound of the Aleph 2 together with the 4435.
The Bass is hitting like... I don't know
A snare is exploding in the middle of the room
I'm shocked from voices as they suddenly appear beside me
I believe I can "see" the circle moves a trumpet player is doing while playing
I hear single persons breathing sitting back in the audience of life recordings.
I never had such an experience.

Frankly I do not understand why not everyone of us experienced DIYers have such Amps at home. They are so easy to build and the value for the money is shocking good.
I'm so angry about myself because I didn't start this project long ago. Now it seems that trying other amps was a waste of time :(

Ian, now I understand :yes:



Pics will follow on weekend.

[Hoerninger]

Guido,

thanks for sharing your experience. Your description sounds very convincing to me.:yes: :thmbsup: :yes:
____________
Peter

[Ian Mackenzie]

Guido,

Its always nice to hear and see the joy that an Aleph project brings.

Are saying you know what real music sounds like......?

Enjoy.

Ian

[Guido]

Are saying you know what real music sounds like......?

Exactly!

Oh, I forgot to say that they work as well as a nice 600W heater which is most welcome as tonight we have 5° Celcius outside :)

[Ian Mackenzie]

Oh yeah that is always a welcome benefit in the cooler months of the year.:)

I vividly recall firing up my Aleph 2 project when I had my JBL 2344A based three way system. It was like they were always meant to be used together.

There is a very nice synergy using that particular combination.

Ian

[LowPhreak]

Good to hear you're happy with the amps. Now the real test begins: long-term satisfaction...or lack of.

I wish I had the room space to do the El Pipe-O.

[Ian Mackenzie]

Good to hear you're happy with the amps. Now the real test begins: long-term satisfaction...or lack of.

I wish I had the room space to do the El Pipe-O.

Go here: http://www.passdiy.com/gallery.htm

[LowPhreak]

Actually Ian, after I saw Guido's latest post last night, I got to thinking, and I wound up exactly there on the DIY gallery. Some very decent...and unique...looking concoctions I'll say. I saw your comments and pix also. Noice woik! :applaud:

So I can start by blaming Guido for this, and now you're in on it too. :wasnt-me: ("The parties of the first part, Your Honor...") :deal:

Now I'll have to decide which of the power amp projects I'm going to take on, b/c more than anything else a much better amp is what I need first now. I'd like at least 150 wpc to drive these 4412's but knowing Pass designs, even that might not be entirely neccesary.

Open for suggestions...

[LowPhreak]

BTW, anyone know where to get the older heat sinks like those of my old Krell KSA-150? (Yeah RIGHT! Wishful thinking?) I've always liked their aesthetic.

They'd be nice to look at mounted to a Pass DIY design - but without the steely greyness of the KSA sound! :scold:

[Zilch]

Order Page: We are all out of boards and parts for current projects.



:(

[Guido]

Order Page: We are all out of boards and parts for current projects.




:(


Order the boards at Kristijan. http://www.kk-pcb.com/
I think letting Rick ship the big full kit packages overseas isn't a good idea.

[Guido]

I'd like at least 150 wpc to drive these 4412's but knowing Pass designs, even that might not be entirely neccesary.

Open for suggestions...

Believe me that you'll NOT need 150 watts. The Aleph 2 will cook your 4412's.
They blow the hell out of the 4435 :bouncy:

[LowPhreak]

Believe me that you'll NOT need 150 watts. The Aleph 2 will cook your 4412's.
Well I wouldn't want to do that, would I? :crying: Actually I am considering any of 60 wpc or more and monoblock.

[Ian Mackenzie]

Why not make what Guido has done and see how it goes!

You might then scale up from the 4412's:)

Ian

[LowPhreak]

You might then scale up from the 4412's:)

Ian

Indeed, that's the plan in the longer term Ian. :yes: Hopefully, at least a big fat pair of 2242/4645C's on the bottom to start with...

[northwood]

:)

[LowPhreak]

Looks nice, resembles a Levinson 33 eh?

[Guido]

Well.....

[Guido]

Will post better outside pics when I have more light ;)

[Earl K]

That's a nice construction job there, Guido !

I loved your initial testimonial :bouncy: Very hard to ignore ;)

How much for the overall ?

Is this process as simple as building an amp from say, "Heathkit" ( in their glory days ) ?

regards

[matsj]

Really nice work Guido.

Br mats

[northwood]

I like dark color stuff
it's cool
very nice job u did

[Guido]

I loved your initial testimonial :bouncy: Very hard to ignore ;)


Really Earl, I'm shocked from the quality of those!





How much for the overall ?


It's 1,500 to 1,600 Euros alltogether. And that's a bargain.





Is this process as simple as building an amp from say, "Heathkit" ( in their glory days ) ?

For you it's no problem at all. There are some traps but with a bit electronics experience it isn't a problem.
Those 2x132,000 uF rails are scary. I burned a 12 Ohm / 10W Resistor with decharging!

[ompdiburi]

Very interesting thread! I am building the same amplifier, can somebody tell me how to select the transistors?
THX!
Giuliano