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Guido
06-20-2007, 03:19 PM
The Aleph 30 is an improved Aleph 3 with 30W clean Class A Power per Channel.
I decided to build 2 Monos.

Details per Channel:
300VA Toroid
10x 15,000 uF Panasonic caps
Toroid inductors in power supply
Superfast rectifier diodes
3 pair of IRFP240 output stage

Case: 3HE 450mm x 300mm
Heatsinks: each 0.4K/W result in 20C above ambient

Should be nice to drive my K2 clones

4313B
06-20-2007, 03:58 PM
We need to talk! :)

Robh3606
06-20-2007, 04:53 PM
Wow that's nice!!

Rob:)

timc
06-21-2007, 01:28 AM
An Aleph 30 Driving K2 Clones??? Hope you mean just the horn(s).

I have built Aleph 1.2 monos earlier, and they dont have a chance at driving the Woofer in the K2. They couldnt even get the Woofer in my L65 Jubal to work properly.

The mids and highs on the other hand is heaven :D

Best regards Tim

Ian Mackenzie
06-21-2007, 03:29 AM
What pcbs are the Guido?

The Aleph 2 was fine running the 4345s and earlier iterations..

It is useful to understand this type of amplifier is not push pull it is SE with an actie current source and will not double the power into 4 and 2 ohm loads normally

A standard (particular model 2, 3, 4, 5) are set up and designed particular set of operating conditions.

You can if you actually understand what you are doing optimise the design meaning the supply voltage, bias, currenty gain and transconductance other output stage for virtually any loudspeaker.

The Aleph 3 was the first one I built back in 2000, then the 5 and later on the Aleph 2 which was a stunner. The Aleph 3 or the 30 are fine or horns.

They do run hot and use a resonable amount of power like 100-150 watts per mono block. If that scares you then this is definately not for you.

The more recent commerical Passlabs X series were a different approach (A/B) biased heavily into class A and have a more dynamic capability and are more suited to low impedance loads. The Aleph owners however prefered to Biamp using the Aleph on the mid and top end where appropriate.

The current Passlabs X.5 series and the most recent AX.5 series have a number of refinements and can handle any load and are sonically superior to earlier Aleph and X Series

Ian

richluvsound
06-21-2007, 08:43 AM
Guido,

as always "PRIMO" they should drive MY K2 clones quite nicely. And just in time for my Birthday. Your so thoughtfull !!!!

Its interesting that some believe they are good for the horns only. Did you learn something from the SAC build? I can see where you had the screws out and the covers off !

There seems to be 2 very informed schools of thought regarding Bi-amping !

Rich

Ian Mackenzie
06-21-2007, 01:08 PM
It fairly simple.

If you don't need to don't.

Please don't go digital with class A amplification

If you do class A is a waste of time.

Guido
06-21-2007, 03:11 PM
An Aleph 30 Driving K2 Clones??? Hope you mean just the horn(s).

I have built Aleph 1.2 monos earlier, and they dont have a chance at driving the Woofer in the K2. They couldnt even get the Woofer in my L65 Jubal to work properly.

The mids and highs on the other hand is heaven :D

Best regards Tim

I really don't know what you are talking about. My Aleph 2 blow the hell out of my 4435.

Guido
06-21-2007, 03:16 PM
What pcbs are the Guido?Ian

BrianGT




The Aleph 2 was fine running the 4345s and earlier iterations..Ian

The Aleph 2 are stunning !! I can hear absolutely no problem for them to drive my 4435's. Just the opposite. They do really kick the 4 2234.

Guido
06-21-2007, 03:18 PM
We need to talk! :)

Whenever you're ready ;)

Ian Mackenzie
06-21-2007, 09:48 PM
I am sure Giskard has the capability to build up some of these..its all a matter of time!

richluvsound
06-22-2007, 12:45 AM
It fairly simple.

If you don't need to don't.

Please don't go digital with class A amplification

If you do class A is a waste of time.

Hi Ian ,
I,m running the 45's with class A SAC mono blocks. Rated at around 35 watts per. They have no problem making the 2245's dance. I think I get the BIG RACK syndrome sometimes ( I need to find a Girl-friend) Besides, your too bloody busy building secret stuff.

The only digital is the itunes signal via fibre- optic to the Quad cdp 2. Then analouge to the nak pre. It sounds superb. But, one always want it to sound better!
I would be better off spending my on room acoustics. I'll just keep reading and someday !!!!!

Have a great day,Richard

Ian Mackenzie
06-22-2007, 01:36 AM
There's nothing particularly secret about the above.

The point to respect is the patent belongs to Pass Labs and any construction can only be for home diy use. They tend to be too heavy to ship so that tends to control that issue.

Yes, class A can be considered a high current designed because of the high standing bias current running through the output stage is constant and there are no non linearity issues per say.

There are good and bad designs of any class of amp and the above are at the top of the heap in terms of subjective performance of their genre.

richluvsound
06-22-2007, 02:00 AM
Ian, I did'nt mention the brand .

I realize the walls have ears after the horn threads got removed.

however, the linearity thing has me :( is it possible to explain in laymans terms ?

Rich

Guido
06-23-2007, 04:20 PM
Today was the first soundcheck.

Only 1 Mono is finshed.

It really kicks the 250ti. Wonderful smooth sound and no lack of power. Good woofer (LE14H-1) control.

:)

Ian Mackenzie
06-23-2007, 06:56 PM
Nice!:)

mpmarino
06-24-2007, 08:49 PM
"however, the linearity thing has me :( is it possible to explain in laymans terms ?"

I'll give an amateur crack at it!

Bipolars and mosfets all have a region in thier curve where the characteristics are most linear. In an AB amp the transistors go from almost off to almost full on - passing in and out of the linear range.

The Aleph amps are biased in such a way that the fets are constantly within the linear region.They virtually are always in the same state. Mr. Pass has done a nice job of doing this with cheap / durable industrial switching fets.

That's how I understand it anyway. I've built three of 'em. I find the highs are incredible but the bass is not killer - but good. Thank you Mr. Pass...

Guido
06-24-2007, 11:49 PM
....but the bass is not killer - but good. ...


Yeah! The bass isn't killer. But it goes deep and it is well controlled. What amaze me is the fact that it sounds so smooooth.
We can't say it is easy to control the two 2234 woofers of the 4435. But the Aleph 2 does a brilliant job.

Ian Mackenzie
06-25-2007, 03:44 AM
Good bass means different things to different people and its only as good as the source.

In general I find the bass of most solid state amps taught in the very deep bass but they often bloom in the upper bass and sound quite Colored.

Moreover the problem is the bass sounds the same of every recording with many amps after a while. This leads me to the conclusion the Aleph is a more accurate sounding amp. It may not rip your head of but neither does real music!

The X Aleph I built is even more impressive in this respect.

What preamp do you guys use? A Pass labs design?

I confess I did not truely appreciate my Alephs till I built the BOSOZ balanced line stage.

Some information on Class A and linearity :

http://www.passdiy.com/pdf/classa_amp.pdf
http://www.passdiy.com/pdf/a40.pdf

yggdrasil
06-25-2007, 08:37 AM
I confess I did not truely appreciate my Alephs till I built the BOSOZ balanced line stage.

I too have built a variation of the BOSOZ. It is simply amazing.

I have a balanced Zenlite in my workshop waiting for heat sinks... Have been waiting a couple of months, and will have to wait a few more months... Plan to use it from midbass and up.

mpmarino
06-25-2007, 01:36 PM
Yes, it is very accurate and I appreciate that. Sometimes it's not as fun as a Krell though! But then you miss the highs, so back to the aleph but.........well...:banghead:

Ian Mackenzie
06-25-2007, 02:18 PM
Each to his own.

At the moment I use the Aleph 2 for really cold days, the X250.5 on a warm day and the X Aleph when I want to have fun.

The Aleph 30 is a very nice amp though.

Guido
07-01-2007, 05:53 AM
Both Amps playing wonderful on my 250Ti.

GREAT Lows and incredible smooth highs. :bouncy:

Ian Mackenzie
07-01-2007, 01:37 PM
Nice work Guido.

Love the Blue Led!

Ian

timc
07-10-2007, 04:58 AM
I really don't know what you are talking about. My Aleph 2 blow the hell out of my 4435.


Sorry for late answer...on hollidays.

Yes it played as loud as the speaker would go, but not nearly controlled and fast enough for my taste. But as stated on a smaller speaker it had superb controll.

Btw: Great project! :applaud:

Best regards

northwood
07-11-2007, 01:24 AM
It seems u got plenty of time:)

Guido
07-11-2007, 11:34 AM
It seems u got plenty of time:)

Good to have you back Northwood. Where the heck have you been?

Oh, time? I work also during the night ;)