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Old 6th June 2003, 03:51 AM   #21
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Well,


I have not done a direct compo yet with the Aleph 2.

Think however the Aleph 2 is more lush and relaxed but in a nice way.


The X Aleph is more of a flicker of light and drop dead gorgous transients.

Its all about taste.

Ian
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Old 6th June 2003, 02:56 PM   #22
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Quote:
Dude, do you really need 10 amps at 13v to get 20 tiny watts?
I assume you are talking about the Xaleph here...
Let me ask you this- Do you really need a class A amp running at 4 amps of bias for 20 watts? How about a p/p class B amp? The point is that it is all about what you system requires, and what level of quality you are going for. What if you have speakers that have a constant low impedance? I think you would need at least some more bias, even if it isn't 10 amps. The bias does have an effect on the sound quality though.
Quote:
I don't want to get into another argument about sims vs actual circuit but to put it in prospective, Nelson biases his xa200 at 8 amps with 30volts rails.
You're talking apples and oranges here... I was talking about the remark you made about the X-lite.
With the <I>ALEPH</I>X, not only do you have an active current source, you have a dynamic active current source! If it was biased with a regular, non-modulated active current source, you would need twice the bias, which would put it at 16 amps! Now, think about using a passive current source, which decreases the efficiency even more. Are you getting the picture yet? Of course, if you don't care about getting full output capability out of the circuit (even into 8 ohms), go ahead and under-bias it as much as you want! I even said that in the first place. Just remember, anyone can criticise someone else's design preferences. It would help your credibility to get your facts straight before you spout off about why a design is so ridiculous. Also, how many posts have you read where increasing the bias on any of the Pass Labs designs or their derivatives has made a significant improvement in sound quality? Nelson himself has said so.
Steve
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Old 6th June 2003, 04:10 PM   #23
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Quote:
Originally posted by nobody special


Yeah, but you're still completely wrong on that one! The high currents needed are for even a 6 ohm load without current limiting... which most 8 ohm speaker get down to.
Simulate it or build it and see for yourself!
Free YOUR mind.
The aleph sources in the X make a big difference. I am actually planning on using 1 device/side in my AlephX, because of everything you mentioned. No need for more. If I were going to be using these with my 4 ohm MTMs, however, I would up the current to be on the safe side. Why limit the output capability when you have the voltage headroom (especially when you are talking about a low powered amp... it would be different if you had a clean 100 watts into 8 or 4 ohms). It all depends on your speakers.
Steve
Steve,
Let us know how your single out devise X works . I plan on building one myself. The speakers are 15 ohm and 100 dB efficient.20 volt or so rails and 1.5 amps through a IRFP044 are what are planned for now. 10 watts is plenty for my system.
Currently I am listening to MikeW's X. The bass and transients are as advertised. It is a revelation in clarity also. The 8 output devises are idling along, putting out mW levels though.
I may be wrong, but hope a single 044 is better suited to drive my speakers. With noraml speakers I bet the sound is much better with a string of 240's and the bias way up.


George
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Old 6th June 2003, 05:27 PM   #24
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George,
I will let you know how it sounds. I am currently working on the chassis, and I have a whole new respect for Peter Daniel's work!
If you are using 1.5A bias per side with 20 volt rails, you will actually get about 40 watts into 15 ohms.
All this praise for the sound is pushing me to finish mine... I can't wait!
I will be using a single IRFP244 per side with about 2.2A bias/side with 13V rails... pretty typical AlephX. I was going to bias it up to 7A total, but I decided to start small and if I like it build one with 20-25V rails and more bias.
Steve
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Old 7th June 2003, 01:05 PM   #25
grataku is offline grataku  United States
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Quote:
Originally posted by nobody special


You're talking apples and oranges here... I was talking about the remark you made about the X-lite.
I don't think so. Never mind the AC current source, I am talking about raw DC bias at various voltage in, YES, alephX but this work for just about any aleph:

30V 8amps Nelson Pass, 12-13V 10amps whoever.

There is no disputing, no trying to spin this simple fact that 10 amps are COMPLETELY UNNECESSARY at 12 v rails and that you'll run out of rail margin long before you run out of current when playing actual music.
Actual THD MEASUREMENTS, not suppositions or conjectures confirm that it is bad in terms of distortions to use such lower rails.

Why anyone would want to listen to higher distortion is beyond me. It comes down to personal preferences I guess, so there is no point in discussing this further.
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Old 7th June 2003, 01:18 PM   #26
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Blown

Well,

That's it for me,

I'm not sure whats going on here so I have elected NOT to enage any futher posts, threads or PICS with this Forum for the moment.

The subject of X appears to create Parkinsons disease which is rather unfortunate for some.

As they say in the classics you are not worthy.

At the start of the original X thread, page one, more meaningful, polite an factual responses came from the creator of all DIY Audio wisdom Grey Rollins.

I will be establishing a home page shortly and those who know me well enough will find out about this.

Of the 700+ A Aleph Boards made, only a handful have published their results.

I mean hello...

Ian


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Old 7th June 2003, 03:14 PM   #27
grataku is offline grataku  United States
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Quote:
Originally posted by macka
[B]Blown

I'm not sure whats going on here so I have elected NOT to enage any futher posts, threads or PICS with this Forum for the moment.
Wonderful! Finish you amp first then you'll have something meaningful to say.

Quote:
The subject of X appears to create Parkinsons disease which is rather unfortunate for some.
Parkinson's is a very serious business not to be taken as a joke, most definitely not to be used as a derogatory term.

Quote:
At the start of the original X thread, page one, more meaningful, polite an factual responses came from the creator of all DIY Audio wisdom Grey Rollins.
The THD measurements I was referring to come from his majesty himself.

Quote:
Of the 700+ A Aleph Boards made, only a handful have published their results. I mean hello...
You have your own reason for leaving the forum. fine. Just don't blame others for your actions.
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Old 7th June 2003, 03:27 PM   #28
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maybe those 700 people are to busy listening to music.....isnt that the subjective goal>????

DIRT®
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Old 7th June 2003, 05:08 PM   #29
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Default No pic yet....

With the likes of Peter's products, it seems as if my amp is rather ordinary. I didn't publish any pics because my Ax has nothing new to offer. Ian, your point hits home with me; even with average looking achievements, we should feel proud to share our endeavors with one another. Frankly, even with low rail voltages, my Ax is a fine sounding amp and I've yet to hear one better. Practically everyone who listens to my system comes away with a smile. Last night one of our guest told me that I've ruined music for her unless she can come over and hear it on my system.

I'm in the process of constructing Nelson's Zenlite. It will resemble the old p to p wired open chassis 2A3 tube amps of yesteryear. Now that's an amp that will give me a reason to post a pic! The maple is so wild that it resembles the finest gunstock. It should be a beaut.

Ian, you should stay. People will be people, always. I for one would really miss you.

John Inlow
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Old 7th June 2003, 05:33 PM   #30
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Quote:
Originally posted by macka
Blown

Well,

That's it for me,

I'm not sure whats going on here so I have elected NOT to enage any futher posts, threads or PICS with this Forum for the moment.

The subject of X appears to create Parkinsons disease which is rather unfortunate for some.

As they say in the classics you are not worthy.

At the start of the original X thread, page one, more meaningful, polite an factual responses came from the creator of all DIY Audio wisdom Grey Rollins.

I will be establishing a home page shortly and those who know me well enough will find out about this.

Of the 700+ A Aleph Boards made, only a handful have published their results.

I mean hello...

Ian


Hang in there Ian, the sometimes heated discussion comes from peole who take building audio too seriously. But we all can learn a thing or two from it.
I am\interested in how other Aleph X amps are operated. The drifting absolute dc offset is very important to me. My drivers are direct connected to the amp without a crossover and the wire is about 40 ga or so in the voice coils. A volt or 2 of dc could smoke them. The natural inductance keeps ac from killing them, but without a blocking cap dc is bad news.
Hope you change your mind and stay around.


George
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