Please look at the measurements I posted in reply 576 of this thread and see if you can duplicate the measurements.
If you look at analytics of that site: You see that people spend an average of 3 minutes on it and leave. More than 50 but less than 60 percent of those viewers only view one page.
Point being, desperate times call for desperate measures. Probably the hope is millions will read this review in awe and refer all of their friends to a set distortion measurements that no one really cares anything about. Running the ranking numbers this site will ultimately live or die by, up.
Those are the numbers that blogger is really concerned with. I spent my 3 minutes on the site (which drove the counter another tick) and read the review. Those numbers may well be what is measured.
But: it sways not my independent review, conducted by me. The ACA amp sounds freaking fantastic!
Why should you listen to either review when you have an amp and can draw your own conclusions?
That blogger should voice his concerns on that site and independently drive his audience in droves to this passionate set of measurements using search engine optimization techniques.
This of course will spark a sermon from the reviewer/blogger. To that blogger: Even if it is the worst in every way measured amplifier. It sounds great! Find some other way to generate traffic. Once the bump of the traffic counter has come and gone, you are right back where you started. Horrible rankings.
That's good work there! As for me duplicating them, I already returned the unit to its owner so can't perform any more measurements.
You know I don't think any of the measurements are invalid, the unit tested over at ASR matched what is published here on diyAudio. It's more about how the measurements are interpreted and presented. When I chose to build an ACA it was after much research and learning (that's the fun right!) on my part to understand if it would work for me. My speakers are fairly easy to drive 8 ohm full rangers and after some measurements I found my listening levels don't exceed 2 watts and really 1 watt and under is most typical. The ACA has worked out well and taught me about some of the basics of this hobby. In fact I had a good chuckle to myself today thinking of the ASR review while listening to Rammstein loud enough that I could hear it clearly while I was out in the yard.
So I think this is where the ASR review falls short. The reviewer presents the standard battery of tests and knowing that these tests are outside the optimal range for the ACA misses the opportunity to educate about why anyone would want to build this amp and what might be it's best use cases. A pity because speaking for myself this little amp has brought me a lot of enjoyment and has been a vehicle to introduced me to a much broader range of the audio hobby than I ever imagined existed.
This reviewer missed nothing. This is the second sentence in the review:
" It is a DIY design by the famous designer, Nelson Pass, meant to be starter amplifier for people new to audio electronics to build."
Same is stated in the conclusion section of the review:
"Conclusions
As a starter hobby amplifier to get some sound coming out of a speaker, with relatively few components, the Pass ACA Class A Amp does the job. Build it, have fun with it and then put it aside and get a proper amplifier. Amplifiers need to have a lot more power. And much less distortion. We are not even close here folks."
So its role as a hobby build is fully recognized. If you want to tell me it is the best amplifier for the job, it simply is not. Certainly not at the price for the one I reviewed. There are cheaper, much lower distortion, more powerful and nicer sounding amplifiers than it. These are facts that are backed by measurements and my listening tests.
I get enjoyment out of a clock radio playing one of my favorite track. What you experienced there is not being challenged whatsoever.
My job is to bring objective, reliable information about performance of audio products. Once you have the data, you can choose to use it in however you wish.
I don't know why you guys are so surprised by my final judgement on this amp. This is how it finished the race:
If you were me, you would whistle dixie while ignoring all the information in the review and misinform the reader that this is a great option for amplification?
your problem is exactly that - you're calling majority of these - amplifiers ..... while I'm recognizing just few of them , worthy of that title
this site is not dealing with mediocre commercial products , except in cases when some is willing to repair his own, and we are helping in that
also , this site is not dealing with advertising
this site is not dealing with mediocre commercial products , except in cases when some is willing to repair his own, and we are helping in that
also , this site is not dealing with advertising
Only site administrators have true site analytics. What source did you use for that information then? Similareweb? If so, this is what they say about ASR: https://pro.similarweb.com/#/websit...diosciencereview.com/*/999/3m?webSource=Total
As you see, it says average time on site is 8 minutes+. Not 3 minutes.
Alexa estimates it at 3:54, rounded to four minutes, not three. Asking Alexa to show the stats for DIYAudio.com reports even lower number of 3:10!
Yeh right. From Similarweb above:
I suggest you stick to the topic of the thread and facts you can defend, not manufacture.
For example enough power is based on use case, your 5 watt measure is not universally applicable.
They are all the ones I have reviewed. The ACR performs worse than all of them by far. The design simply is not performant. Read Rod's article if you think a MOSFET power stage is the right solution: Death of Zen - A new Class-A power amp
"Having looked at the original and many of the 'improvements' currently on the web, I did a few tests of my own and frankly, found the amp lacking in the fidelity department. Hi-Fi this most certainly is not."
There is zero advertising or sponsorship on ASR Forum. Kind donations from members and my own funds keep it going.
I consider DIYAudio and ASR to be complimentary sites. I routinely review products with the same silicon or module used in commercial amplifiers. I also test DIY builds like the ACA we are discussing.
This notion of "us versus them" is very much unlike the very positive impression I have of DIYAudio.
I hope you guys keep your emotions in check and start to value objective information. Engineers thrive on that. You will never be good at this field if you continue to act the way you have been. Learn to separate your emotions from facts. The owner of the ACA amp has done that. Not sure why the few of you are having so much angst over learning more about performance of these designs.
5 watt dashboard view has nothing to do with use case. Use case comes later as full power is measured versus distortion and noise into different loads.
All amplifiers tested can reach 5 watts so it is a good common data point to have across wide range of amplifiers. Don't know why you think that represents a use case.
This is getting boring and filling my inbox full of notifications about the ACA that I don't need to know or hear. I could unsubscribe from the thread but then i'd miss out on interesting stuff and comments from people who own build and modify the product.
Amirmaj kindly have sex and travel - leave any further comments on the ACA on the forum you run not this one.
Amirmaj kindly have sex and travel - leave any further comments on the ACA on the forum you run not this one.
And it's the chart you used to show ranking. Meaningful if you care about performance at 5 watts into 4 ohm. That I would call a use case
... blah, blah, ...
And the sound pressure level instruments on the side of my head tell me that the ACA is a great little unit. On top of that, it has opened up a world of possibilities that I hadn't thought were possible a year, or so, ago. And, last week, I shook its designer by the hand and gave him my heart felt thanks. That's what's important to me.
How about we get back to the regular programme?
And that includes talking about cool tweaks to build on the base design. I look forward to reading about that sort of creative insight. It's very easy to criticise. It takes true skill and depth of knowledge to be innovative and inventive. This thread is also about helping people start their journey and successfully finish their builds. More of that content please.
And the sound pressure level instruments on the side of my head tell me that the ACA is a great little unit. On top of that, it has opened up a world of possibilities that I hadn't thought were possible a year, or so, ago. And, last week, I shook its designer by the hand and gave him my heart felt thanks. That's what's important to me.
How about we get back to the regular programme?
And that includes talking about cool tweaks to build on the base design. I look forward to reading about that sort of creative insight. It's very easy to criticise. It takes true skill and depth of knowledge to be innovative and inventive. This thread is also about helping people start their journey and successfully finish their builds. More of that content please.
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I think it's a good option (and economical) if you use planar headphones like Audeze, Mrspeakers.... With the HD800 I am enjoying a lot.
With more sensitive headphones type Grade, Fostex ... sounds great but I think it is more prone to noises.
As for the construction, what has given me the most problems is the arrangement of the transformer. I had to spend a lot of time moving it until I found a place/position where no noise induced.
As its use is going to be almost exclusively for headphones, I am thinking of switching to B + 24vdc.
I have added a R100 resistor in series with the headphone output. I know it's not something very elegant but it works.
Now I can use the most sensitive headphones that I have without problems. I have noticed that I have lost some "claw" with hard headphones like the HD800 or the Audeze.
I have to value everything a little.
I'm sorry to further clog this thread with my 2cents on amirmaj's ominous blog, but there's something itching me:
It may be that those measurements are correct as they were published (as far as I can see, nobody is denying them here), and that nobody here really wants to talk about those figures. (they might be worrisome to us beginners because we're supposed to have built one great little amp, thus it can't have so and so much whatever number).
But then amirmaj comes with the claim that "there are nicer sounding amplifiers […]. These are facts […| backed by measurements and my listening tests.
You insinuate that you are measuring the nice-soundingness of an amp by measurements... (yeah I know, listening tests, read on: )
Concerning those listening tests,
... I have no Idea how they were made. But this is so… how should I say… … well,
Our ACAmps are all not only sounding very nice, they also deliver plenty of noise (loud music, that is).
I don't know much about electronics, but I trust my ears. My conclusion so far is that something has gone terribly wrong in that test of him. He either didn't want to admit it's not about the numbers, or he plugged his ACA the wrong way.
Please amirjay, leave this thread, open up your own.
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Moderators?
Where are you?
This thread has been clogged by a certain self promoting "reviewer", there have been several attempts from other forum members to stop this nonsense and not a word from any of the moderators.
AFAIK trolling or self promotion is not permitted here but here we go...
I, and many other people advised this guy to start his own thread and discuss his "reviews" for as long as he likes, but not to hijack this particular thread.
Still, he is back with a lot of vigor and no-one that has the power does anything about this.
Where are you?
This thread has been clogged by a certain self promoting "reviewer", there have been several attempts from other forum members to stop this nonsense and not a word from any of the moderators.
AFAIK trolling or self promotion is not permitted here but here we go...
I, and many other people advised this guy to start his own thread and discuss his "reviews" for as long as he likes, but not to hijack this particular thread.
Still, he is back with a lot of vigor and no-one that has the power does anything about this.
Well, to be honest, Amir didn't come here on his own idea. Someone posted a link to his review and said nasty things, so naturally Amir came over to give his view. To sides of the story which seems fair.
About 5 or 6 years ago, I did a European AmpCamp here in The Netherlands. We build about 28 pairs of ACA monoblocks in a day. It was great, people who hardly knew which end of a solder iron to hold went home proudly with a nice sounding amplifier set.
A year later I did the same with a small, 17 liter reflex speaker with a single wideband driver. Again, almost 30 pairs, in a single day, some by the same people that build the ACA before. Some fathers came with their teenage son or daughter even! They really loved their speakers, it was great fun
Now, to be honest, for about 1/4 of the cost of the speaker kit they could buy a pair with better performance. But the point wasn't to build the worlds best speaker for the least money. Just as my AmpCamps goal was not to build the worlds best sounding amp for the least money.
The goal was otherwise and has been mentioned before and noted in a few places in Amir's review.
Many people here stated they love their amp, they love the sound, and they are totally happy. So what's all the fuss? You know even by just glancing at the schematic that it can't be high-end, it can't be powerful and super low distortion. So why trying to shoot the guy who actually says what you all, honestly, already know? Put up some music and be happy!
Jan
About 5 or 6 years ago, I did a European AmpCamp here in The Netherlands. We build about 28 pairs of ACA monoblocks in a day. It was great, people who hardly knew which end of a solder iron to hold went home proudly with a nice sounding amplifier set.
A year later I did the same with a small, 17 liter reflex speaker with a single wideband driver. Again, almost 30 pairs, in a single day, some by the same people that build the ACA before. Some fathers came with their teenage son or daughter even! They really loved their speakers, it was great fun
Now, to be honest, for about 1/4 of the cost of the speaker kit they could buy a pair with better performance. But the point wasn't to build the worlds best speaker for the least money. Just as my AmpCamps goal was not to build the worlds best sounding amp for the least money.
The goal was otherwise and has been mentioned before and noted in a few places in Amir's review.
Many people here stated they love their amp, they love the sound, and they are totally happy. So what's all the fuss? You know even by just glancing at the schematic that it can't be high-end, it can't be powerful and super low distortion. So why trying to shoot the guy who actually says what you all, honestly, already know? Put up some music and be happy!
Jan
@Stanislav: this is a free forum and if you abide by the rules your view on audio can not be censured, nor should it be.
In fact, if the mods would throw Amir out of this thread (which I am sure they will not), that would be a black day for diyaudio!
Just as throwing you out would be a black day (unless you violated the rules). I do not in any way agree with you but will defend your right to speak up.
Jan
In fact, if the mods would throw Amir out of this thread (which I am sure they will not), that would be a black day for diyaudio!
Just as throwing you out would be a black day (unless you violated the rules). I do not in any way agree with you but will defend your right to speak up.
Jan
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