Lower rail voltage means lower power, but also means a higher bias current at the same dissipation level.
Then there's the option of playing with the AC bias factor, alter it to 0.25 (down from 0.5) and peak output current will be four times the bias level.
The Aleph 2 is biased at 0.5A per output device, makes 3 Amps total quiescent current.
Read the service manual : Peak output is 10 Amps, makes 200W continuous in 4 Ohm theoretically.
For less easy loudspeakers a better choice.
Ahhh that they do, most speakers do as a matter of fact, always sounding more "alive" when fed some power...
High sensitivity 2 way speakers sound unbalanced to me, well everyone i have ever heard. To get high sensitivity and a good balance require a large multi driver speaker 3-4 way at the very least.
regards,
High sensitivity 2 way speakers sound unbalanced to me, well everyone i have ever heard. To get high sensitivity and a good balance require a large multi driver speaker 3-4 way at the very least.
regards,
Wow, tastes do vary...I find the 3 and 4 ways with poorer balance than the 2 ways!
Russellc
OK, sounds like I have picked the correct amp for my purposes, thanks for the insight.
Russellc
What is there to say ?
The Alephs are not classic single-ended amps with fixed bias, but have a steady-state bias (no signal) plus dynamic bias (with signal at input/output) of the current source.
(as to be expected from the master of sliding bias arrangements in Threshold amps)
My candid camera short version : the connection between output and biasing arrangement fools the bias transistor in believing that the voltage drop across the output source resistor goes down, in effect : more quiescent current (of the current source).
For the long version, read Zen Part II.
Personally, i do not view the Aleph amps as True Class A, but semi Class A.
Similar to Krell's sustained bias plateau, Threshold's sliding stuff.
Without the dynamic bias thingy, it would become a standard SE amp, max output current is quiescent current => AC current gain factor = 1
If the AC gain setting is altered to something near 0, the amp starts to resemble push-pull (high bias Class AB )
See bottom half of the output stage. What happens there when the positive output current goes beyond the static bias current level ?
So :
0 = PP Class AB
1 = SE Class A
Therefore 0.5 = 1/2 Class A (aka semi)
(so, each Aleph amp can be custom tailored to the loudspeaker system in question. Rotten LSP needs bigger supercharger)
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I can believe that ... Poorly made/designed speakers, nothing to do with them being multi-way. Done right , no single speaker or 2 way will come close...
Much easier to get a 2 way correct.....................
I can believe that ... Poorly made/designed speakers, nothing to do with them being multi-way. Done right , no single speaker or 2 way will come close...
Much easier to get a 2 way correct.....................
IMMO multiway = multi point sources = multi-problems.
I heard and adjusted (and made) dozens of multiway systems, and my feelings is the best one is the one way (But is very difficult to achive a good performance, my Quad ESL can, but the drawback are a low headroom), the second best is two way, the third best is three way.........
But is my taste
The quad is a 2 way ....
I'm sorry cannot concur with your observations, what you have described is a poorly designed multi-way speakers, more specifically there x-overs. Done correctly you could be standing less than 1 M away and cannot point out the drivers..
regards,
I'm sorry cannot concur with your observations, what you have described is a poorly designed multi-way speakers, more specifically there x-overs. Done correctly you could be standing less than 1 M away and cannot point out the drivers..
regards,
IMMO multiway = multi point sources = multi-problems.
I heard and adjusted (and made) dozens of multiway systems, and my feelings is the best one is the one way (But is very difficult to achive a good performance, my Quad ESL can, but the drawback are a low headroom), the second best is two way, the third best is three way.........
But is my taste
The quad is a 2 way ....
I'm sorry cannot concur with your observations, what you have described is a poorly designed multi-way speakers, more specifically there x-overs. Done correctly you could be standing less than 1 M away and cannot point out the drivers..
regards,
One way (ESL63)
Part of my work is adjust PA systems, I heard everything, from poorly designed to well designed, this is the reason on my oppinion.
Regards
I can believe that ... Poorly made/designed speakers, nothing to do with them being multi-way. Done right , no single speaker or 2 way will come close...
Much easier to get a 2 way correct.....................
I think we are mostly in agreement, 2 way is easier. That said, when I've listened to multiways done correctly, there seems to a limited area of the listening area that gets the really good treatment, and not so good out of sweet spot. The last several years I have really gotten a kick building 2-ways with larger pro type woofers and compression drivers on constant directivity wave guides. There is something to this constant directivity thing, with its ultra wide sweet spots and extremely stable imaging. The crossover MUST be properly designed for home hi fi use, removing the shout and inserting or designing in compensation to match the compression drivers sensitivity to that of the woofer, and at the same time flattening the high end response for proper extension. In the spirit of the Econowave speakers Zilch designed and built is what these 2 ways I refer to are.
With your multiways, are you talking DIY or factory built commercial speakers? What are some of you favorites? I am mainly interested in speakers with high sensitivity/effeciency, because of some of the amplification I have been using lately requires it.
Thanks for the banter and responses!
Russellc
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Nothing much happens into an 8 ohm load. The quiescent current goes up if the amp is biased to the same voltage point. The power to the load is the same.
You could have 100 mosfets. Same.
Where more mosfets makes a difference is when you want to drive a LOWER Z load, because they require more current when the input voltage to the amp is the same (or the output swing is the same).
Someone figured the power based on the rail voltage. Take 1/2 the rail to rail voltage and multiply by 1.414 then apply ohms law. IF you want to spec it the same as all other amps are spec'd.
What I think some are losing sight of is that the gain of the F5 is rather a lot LOWER than a standard power amp. Most power amps tend to have about 25-6dB of gain. The F5 has about 10dB less gain. This makes it sound different than expected, the output level from the source has to be higher (that sounds different if it's a preamp with gain). And also how you build and bias the F5 causes rather substantial changes in the way it sounds.
Everyone is NOT listening to the same F5 amplifier!
_-_-bear
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