I too had to swallow. Then I just played a favorite record with ACAmp. Thus I could get over the fact that this is not a conventional amplifier. Just listen to that beast. Build another one. 😀
As Nelson said at BAF2019, "it's entertainment".
And to paraphrase Rusty Crowe from "Gladiator", "are you not entertained?"
Measurements and specs have there place but placing appropriate reliance on your own ears is where I'd suggest you fall back to. If your ACA doesn't sound right to you, post some photos, describe the issue and do a voltage survey with your DMM. Report back the details and you'll get mountains of support and help here from people who enjoy listening to music.
Some places on the internet aren't that helpful. I'd suggest avoiding the grumps out there.
What I found strange was down in post 109 the reviewer tries Bridge mode with a 4 Ohm load and is surprised to see H3 now dominates. To me, this suggests the reviewer is looking for something to be critical of, while pulling the wool over the eyes of the technically unsophisticated reader.
Tester was requested by Tom Christiansen to test performance in bridged mode. Good to have complete results. There was no ocular wool deployment.
i built two versions, one is fully balanced and the other one single ended bridged.....both sounded awesome...
In an independent review, conducted by me. No matter what someones measured results are - these amps sound freakin fantastic! Back to the music.
Pass DIY Addict
Joined 2000
Paid Member
And considering that I built my amp for about $55-60 complete with recycled sinks, a block of wood, and a laptop power supply that was already laying around in my parts box, it's a screaming good deal, too! I've already built several and given them as gifts...
One thing that strikes me odd is the comment about how the reviewer could not get any real volume from the speakers for the listening test. The speakers used in the review were 86db sensitive and 8 ohm, my speakers are 88db sensitive 8 ohm full rangers plus I have 3db of BSC filter. They go beyond what I consider loud listening in my living room. Distortion or no what is so fundamentally different from my setup to what the tester used?
PCB-connection tips?
Good morning!
I know I'll tear my ACAmp apart to try to implement some of the tweaks and improvements. Since this means connecting/disconnecting the board "many" times, I think it would be reasonable to work with PCB-connectors of sorts.
I bet the distances of the solder-points are according to some standard, but which?
I'll probably need something like a molex, solder-pin, quick-fix connector...
I've seen some in ACAmps, here in the forums, can I ask what part you were using?
thank you!
david
Good morning!
I know I'll tear my ACAmp apart to try to implement some of the tweaks and improvements. Since this means connecting/disconnecting the board "many" times, I think it would be reasonable to work with PCB-connectors of sorts.
I bet the distances of the solder-points are according to some standard, but which?
I'll probably need something like a molex, solder-pin, quick-fix connector...
I've seen some in ACAmps, here in the forums, can I ask what part you were using?
thank you!
david
Astromo
I agree with you. People should not listen to preachers of a healthy diet. Of course, low-calorie food can be delicious - sometimes. Beef steak with roasted potatoes and some good sauce is always excellent. And don't say no !
I agree with you. People should not listen to preachers of a healthy diet. Of course, low-calorie food can be delicious - sometimes. Beef steak with roasted potatoes and some good sauce is always excellent. And don't say no !
This was also the part of the review I found most strange. The tester should redo this test and measure on speaker input if he gets full signal. A 5V RMS signal on 86 dB speakers should be louder than just background music?
Room size and listening distance change sufficient power thresholds a lot. Listening habits are a significant factor as well. Users of high power amps usually listen loud and uncompressed in bigger rooms with moderate efficiency speakers of larger voice coils poised for impressive replay of also EDM and other power loving genres.
I used my ACA with fifty years old philips full range drivers. I was using B1 at that time.. And it was magical.. Unfortunately I don't have full rangers anymore for listening because of WAF issues (really big boxes!)....
I also used ACA with 87db three ways and used BA3 pre and it still delivers enough juice for speakers..
I think reviewer doesn't have enough input level to get sufficient spl.
I also used ACA with 87db three ways and used BA3 pre and it still delivers enough juice for speakers..
I think reviewer doesn't have enough input level to get sufficient spl.
ACA should be at its dynamic best on 95dB SPL/W/M speakers or more. Never pushed beyond 2-3V RMS output so it gives a moderate bloom of harmonic coloring in subjectively high enough peaks while getting progressively resolving in fade outs. Its blacker background than most tube amps and going to its linear best the other way than most higher SINAD performance solid state amps should be its two trick pony mojo.
is there any difference of so called
voltage hungry and current hungry speaker or amplifier design?
what about this ACA
voltage hungry and current hungry speaker or amplifier design?
what about this ACA
Yes there is, you will find it in speaker sensitivity and in speaker impedance/frequency plot. ACA would excel neither in voltage swing, nor in current supplied.
ACA works very well with Castle Howard 1/4 wave 2.5 way speakers, they are a nominal 8 ohm load of 92dB sensitivity.