Very favorably I would say, but a lot depends on your speaker load.
With the right speakers it can be (to borrow from Mr. Pass) a party animal.
The more benign the speaker load (read impedance and phase) the better the sound.
In my case the ACA drives a 3-way, 1st order Series XO (93 dB) with great gusto, unbelievable clarity, drive and control.
The pre is B1 so all the gain comes from the ACA.
A friend of mine who has Aleph 2, F5 and F6 could not believe his ears last week at the delivery of my ACA.
With the right speakers it can be (to borrow from Mr. Pass) a party animal.
The more benign the speaker load (read impedance and phase) the better the sound.
In my case the ACA drives a 3-way, 1st order Series XO (93 dB) with great gusto, unbelievable clarity, drive and control.
The pre is B1 so all the gain comes from the ACA.
A friend of mine who has Aleph 2, F5 and F6 could not believe his ears last week at the delivery of my ACA.
I enjoy it with Kef 101/2 and either a DCB1 (no gain), or a WLS pre. Very satisfied, but I am not yet able to compare it to other FW, F4 too young (and without appropriate load as of yet).
Early comparison: ACA is more pleasant, „softer“ or (ahem) velvety…
Early comparison: ACA is more pleasant, „softer“ or (ahem) velvety…
It is the kit from the store, i.e. the Amp Camp Amp. I have it hooked up to a set of 4 ohm/96.7DB speakers and think is sounds pretty amazing as-is. Was really after any opinion of what the improvements are in the amps as you move up in complexity of the kit(s)/options available to build. Seems like a really simple circuit can deliver a very good result, thus are the more complex builds a futher improvement or just a different sound?
First, remember what Nelson likes to say, this is entertainment not dialysis, so start there. 😉
With that in mind, you will find that they are different for sure, but you need to be the judge of "better".
--Tom
I can't comment as I only have two ACAs that I run as bridged monos. Would love to be able to compare them to an F6 or F8, some time.
The general consensus by many of the great amplifier designers, though, is that simpler circuits sound better than complex ones.
But, I can tell you this: give them at least a good 100 hours of burn-in before making any final conclusions. The ACA will really open up, and sound more expansive, highs will be more extended, and the overall presentation more natural, and as Hans Beekhuizen says, "relaxed".
The general consensus by many of the great amplifier designers, though, is that simpler circuits sound better than complex ones.
But, I can tell you this: give them at least a good 100 hours of burn-in before making any final conclusions. The ACA will really open up, and sound more expansive, highs will be more extended, and the overall presentation more natural, and as Hans Beekhuizen says, "relaxed".
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Cool, I'll sit back and just enjoy for awhile. I built a tube amp previously and found the sound changed on it after a lot of use, didn't think there would be too much to wear-in (so to speak) on this little amp....
Give it a hundred hours or more and you will be very pleasantly surprised.
There's always burn-in on components and cables used for audio or video applications, including the components in the circuitry and the hook-up wire. Also, when installing or moving cables, they also need time to settle, as moving, handling, or transporting them imparts vibration, which results in triboelectric noise in their dielectrics.
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It's interesting, my favorite Nelson Pass design happens to always be the one I'm listening to at the time (ACA mono blocks at the moment). I've built a few of the First Watt clone amps, and two ACA's. Also have heard Pass Labs equipment on a couple of occasions. I have these moments while listening to one of these amps, that the feeling... "it can't get any better than THIS". But I've enjoyed this sensation several time now, in fact with each Pass Design I've heard.
P.S. I think most build the ACA first and then move on to FW designs...I did the opposite.
P.S. I think most build the ACA first and then move on to FW designs...I did the opposite.
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<chuckle> Power your FW amps with a Shunyata NR power cord, or better yet, a Shunyata NR power cord plugged into a Shunyata Everest power distributor, and you'll hear first-hand how much better it can get.
Per your point, though, I would love to have a Pass Class A or First Watt Class A amp on-hand for reviewing duties for TAS. Cheers.
I have the ACA's plugged into a "Fo-Felix" line conditioner...seems to work pretty good to me.
I wouldn't be judging things in the absence of data or direct experience.
So...how about some data? 😉
Shunyata Research Venom 14 Digital power cord demonstration - YouTube
and....
V14D Demo 3 - YouTube
From a mean noise value ~110 using generic black power cords to 0.1 with two Venom V14D in series....
0.1/110= 9.09 X 10 ^-4 or 0.000909 the amount of noise using 2 generic black power cords.
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One doesn't need a Double Blind to use a spectrophotomer. Or a voltmeter, for that matter.
Did I need to do a Double Blind when I used a voltmeter to properly bias the pots for the power transistors duing my ACA build? No.
The data is the data, what's required is a well-designed and properly controlled experiment.
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He's paying for the amp :^) Over time we've become quite good friends and I've been working on a dsp design he can use in the future! Also a stream thing 😉
