Due to the release of a transformer based passive preamp, some people in my local community are interested in passive preamp. A few of them seems to interested in my set up too:
Aleph L + Aleph 3 + Thiels 1.5
Since Aleph L is no longer in production, they cannot buy it now.
They urge me to tell them the design and specification of the combo.
So that they can diy it.
Specifically, I would like to seek help in the following:
1. Since impedance varies with volume in passive pre (right? I am not an expert.), what's the impact on sound? How can we alleviate its effect? Does the resistance value of attenuator important?
2. How can we match the input impedance and output impedance of a preamp [Aleph L: input imp=20Kohm, output imp.=250ohm]?
3. How can we choose the input impedance of the power amp?
Specifically, what value of input cap. is good for a power amp using with a passive preamp? [it seems that Aleph 3 is Direct coupple. Does it mean no input cap.?]
4. I have been puzzled for a decade why Papa designed a passive preamp for Aleph 3 whose gain is only 20dB? [Is cost only the concern here?] Will it compromise the dynamics?
Thanks Papa, I love this combo very much. Passive pre, Single end, Class A & non-NF design help me enjoy the beauty of pure music.
Aleph L + Aleph 3 + Thiels 1.5
Since Aleph L is no longer in production, they cannot buy it now.
They urge me to tell them the design and specification of the combo.
So that they can diy it.
Specifically, I would like to seek help in the following:
1. Since impedance varies with volume in passive pre (right? I am not an expert.), what's the impact on sound? How can we alleviate its effect? Does the resistance value of attenuator important?
2. How can we match the input impedance and output impedance of a preamp [Aleph L: input imp=20Kohm, output imp.=250ohm]?
3. How can we choose the input impedance of the power amp?
Specifically, what value of input cap. is good for a power amp using with a passive preamp? [it seems that Aleph 3 is Direct coupple. Does it mean no input cap.?]
4. I have been puzzled for a decade why Papa designed a passive preamp for Aleph 3 whose gain is only 20dB? [Is cost only the concern here?] Will it compromise the dynamics?
Thanks Papa, I love this combo very much. Passive pre, Single end, Class A & non-NF design help me enjoy the beauty of pure music.
Assuming that B&W_arthur is asking something about the Aleph preamp, as opposed to a "normal" passive preamp, I'm assuming that he anticipates needing gain at least some of the time. Since there's no way to get gain out of a passive preamp (unless you want to get into transformers--something that is alien to the Aleph series), we're led to the idea that B&W_arthur wants an active preamp.
Yes, the L does tend to invite a semantic argument, but until it's clearer what he wants, I'm left guessing that he's needing gain, hence an active preamp, which is what the MOSFET is in the Aleph to provide.
Grey
Yes, the L does tend to invite a semantic argument, but until it's clearer what he wants, I'm left guessing that he's needing gain, hence an active preamp, which is what the MOSFET is in the Aleph to provide.
Grey
OT question.....
Did anyone compare the sound of Aleph L (first variation- either 12 or 18 DB gain) with Bride of Zen? How would you describe the difference?
B&W_arthur, if you need a "passive" pre, just build a buffer, either a mosfet one, like in ZEN V4, or, better yet, use a Jfet, like in a "Buffer for Blues"...
Vix
Did anyone compare the sound of Aleph L (first variation- either 12 or 18 DB gain) with Bride of Zen? How would you describe the difference?
B&W_arthur, if you need a "passive" pre, just build a buffer, either a mosfet one, like in ZEN V4, or, better yet, use a Jfet, like in a "Buffer for Blues"...
Vix
Vix said:
They are quite similar.
Referencing the later Aleph L, at the unity gain position of the
volume control, the preamp was a straight through, and I would
consider it passive below that point. Above unity, the output
looked at a divider between input and the output of an active
section. I thought it worked splendidly, but it did not seem to
catch the imagination of the audiophile community as much as
I would have expected.
Nelson Pass said:
I've learned not to rely too much on my market simulation software.
It's the customer-device models that are at fault. Savvy simulation mavens such as yourself know that.
At the moment I'm making bets with myself as to how many posts will be devoted to the semantic difficulties raised by the L.
It slices! It dices! It will even defrost the cat and paint the refrigerator! Oh, and it makes music, too...
Grey
GRollins said:
Yes, but you need a preamp to light that fire
And you may want to listen to some music while BBQ-ing
By the way, I just wonder how many high quality (amps, cars, whatever) gear never made its way because customers were not able to realize the potential.
An average customer will hardly realize why there's an amp (or preamp) with zero gain!? I have a feeling that some people first look into shortcomings of a certain gear, and then, as soon as they notice something they don't like or don't understand, they write it off. Zero gain? No..I need something that amplifies....
Vix
Nelson Pass said:
They are quite similar.
...... I thought it worked splendidly, but it did not seem to
catch the imagination of the audiophile community as much as
I would have expected.
Yes, I think that it is under-rated.
The performance of Aleph L is simply excellent.
My friend's question is :
what is the value of the input capacitor of Aleph 3?
[so that it matches Alpeh L used as a passive preamp well]
Answer to this question is appreciated.
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