ASR took the fun out of amp reviews

[Tenorman]

A guy like that still says "trust your ears"? Interesting. He could just be another "audiophile"

“A guy like that” ? What does that even mean ? Have you met the guy ? If not , then how can you label him as “a guy like that” ? Honestly , I’ve just discovered this website - but the sanctimony, cynicism and condescension on display here is disappointing. Especially, since not one of you has actually even heard the amplifier in question. If “trusting your ears” somehow makes one some kind of shallow audiophile - then millions of genuine music lovers are in serious trouble . Happy listening . Correction - happy measuring

 

[ta240]

... In my email correspondence with from Mr. Karaki regarding the Stereophile review - he told me that he took strong issue with some of Stereophile’s measurements. He stands behind his design ...

Did he seem to think their measurements were incorrect or that they don't matter?

Surely he must have some technical knowledge in regard to proper circuit design ? Based on some of the comments here - apparently not .

I'm sure he does, but he either lacks knowledge of tube amp design layout or doesn't care about the interference, which some have commented may not be audible. It still seems like it would have been quite easy to correct with a slightly wider case, some shielding and possibly turning the power transformer.

As the happy owner of the HFSA-01 I can assure you - it sounds amazing

And I always say on here that if you enjoy it then, enjoy it.

My issue with the review was the two parts of the review being in opposition. One raves about the build and states '"The power supply section is completely isolated between the vacuum tube and semiconductor to completely eliminate any interference", so the designer worried about interference getting through the wires from the power supply but completely ignored the magnetic field created by the transformer, which the measurements indicate.

 

[Blumlein 88]

“A guy like that” ? What does that even mean ? Have you met the guy ? If not , then how can you label him as “a guy like that” ? Honestly , I’ve just discovered this website - but the sanctimony, cynicism and condescension on display here is disappointing. Especially, since not one of you has actually even heard the amplifier in question. If “trusting your ears” somehow makes one some kind of shallow audiophile - then millions of genuine music lovers are in serious trouble . Happy listening . Correction - happy measuring

You will find no forum on the internet that trusts our ears as much as members here. We trust our hears and what we hear. But ears only. Not ears, eyes, biasing by subjective review. Just ears.

On top of that, when a device departs from neutrality sufficiently we have absolutely zero need to hear it to know it alters what you hear. Even we may or may not like what that sounds like. But we don't have to hear it to know it is not neutral, not transparent, not true to the source. We do have happy listening to music, because once we have components we can count on to be transparent we don't worry about all the odd things many audiophiles end up nervously considering and spending money upon on some sort of merry go round of what is really good.

So in the case of this one non-transparent amplifier the criticism of others not having actually heard it is not nearly the devastating retort you think it is. Your amplifier may sound amazing with your speakers. And if you are happy there is nothing more you need.

 

[Chrispy]

“A guy like that” ? What does that even mean ? Have you met the guy ? If not , then how can you label him as “a guy like that” ? Honestly , I’ve just discovered this website - but the sanctimony, cynicism and condescension on display here is disappointing. Especially, since not one of you has actually even heard the amplifier in question. If “trusting your ears” somehow makes one some kind of shallow audiophile - then millions of genuine music lovers are in serious trouble . Happy listening . Correction - happy measuring

Just meant a scientist that wants you to judge by largely a non-scientific method is just not interesting/important.

 

[RayDunzl]

Toobs.

Dad and I built one of these when I was about 8 years old.

EICO HF-81 integrated amplifier

If you spotted an EICO HF-81 at the local Goodwill, you'd think nothing of this plain-Jane integrated amplifier in its nondescript gray case. But if you kept on walking, you would have passed up one of the best-kept audio secrets of all time. The HF-81 hails from hi-fi's pioneer days, before...

www.stereophile.com

I used it personally for a couple of years later, till it got rained on.

I thought it sounded just fine.

I had no idea how it worked back then.

The measurements don't measure up, of course.

If I still had it I'd probably still be using it somewhere.

 

[mhardy6647]

Toobs.

Dad and I built one of these when I was about 8 years old.

EICO HF-81 integrated amplifier

If you spotted an EICO HF-81 at the local Goodwill, you'd think nothing of this plain-Jane integrated amplifier in its nondescript gray case. But if you kept on walking, you would have passed up one of the best-kept audio secrets of all time. The HF-81 hails from hi-fi's pioneer days, before...

www.stereophile.com

I used it personally for a couple of years later, till it got rained on.

I thought it sounded just fine.

I had no idea how it worked back then.

The measurements don't measure up, of course.

If I still had it I'd probably still be using it somewhere.

Very cool.
Fine amplifiers indeed.
I've (still) got one -- it is as old as I am.
It is in considerably better condition, and I daresay it sounds better, too.


My father loved all things EICO, although he didn't build this particular HF-81.
I do still have the HFT-90 tuner he built, and that I quite literally grew up with.

 

[RayDunzl]

We built a matching FM mono tuner, too.

 

[Blumlein 88]

Toobs.

Dad and I built one of these when I was about 8 years old.

EICO HF-81 integrated amplifier

If you spotted an EICO HF-81 at the local Goodwill, you'd think nothing of this plain-Jane integrated amplifier in its nondescript gray case. But if you kept on walking, you would have passed up one of the best-kept audio secrets of all time. The HF-81 hails from hi-fi's pioneer days, before...

www.stereophile.com

I used it personally for a couple of years later, till it got rained on.

I thought it sounded just fine.

I had no idea how it worked back then.

The measurements don't measure up, of course.

If I still had it I'd probably still be using it somewhere.

I've had one too. It would measure around as good as the Aurorasound though probably with less output impedance.

I had one of these for awhile. Fisher X100 integrated. Paid $2 at an estate sale. Worked perfectly. Same tubes as the Aurasound (6BQ5) good for 17 wpc. Was fun to listen to. Had it on some old Quads for a time.

 

[kemmler3D]

You will find no forum on the internet that trusts our ears as much as members here. We trust our hears and what we hear. But ears only. Not ears, eyes, biasing by subjective review. Just ears.

On top of that, when a device departs from neutrality sufficiently we have absolutely zero need to hear it to know it alters what you hear. Even we may or may not like what that sounds like. But we don't have to hear it to know it is not neutral, not transparent, not true to the source. We do have happy listening to music, because once we have components we can count on to be transparent we don't worry about all the odd things many audiophiles end up nervously considering and spending money upon on some sort of merry go round of what is really good.

So in the case of this one non-transparent amplifier the criticism of others not having actually heard it is not nearly the devastating retort you think it is. Your amplifier may sound amazing with your speakers. And if you are happy there is nothing more you need.

Was going to say something similar... trust your ears, just so long as the eyes are not allowed to pipe up with their infernal lies.

 

[kemmler3D]

View attachment 443503

Plus an extra -1dB preamp to add to the altered FR for volume matching

Preamp: -1 dB
Filter: ON PK Fc 65 Hz Gain 2 dB Q 1
Filter: ON PK Fc 1600 Hz Gain 2 dB Q 0.5
Filter: ON PK Fc 4500 Hz Gain -2 dB Q 2

Credit to @wwenze for this preset and @Tenorman for appropriate skepticism.

I just tried this setting out and it's definitely audible, but not as blatant as I expected just listening to pop music. I am 95% sure I could pass an ABX but not necessarily on every piece of music. The difference is beyond obvious with pink noise.

It is about 1000 times more coloration than I want from an amp, personally. But, I could also imagine the coloration escaping notice in a normal listening scenario.

 

[Old_School_Brad]

Appealing to authority rarely strengthens an argument. In my experience, department heads -at least in engineering within the energy sector -typically don’t have in-depth, hands-on knowledge of the finer technical details. What they do have is a solid grasp of the bigger picture, the ability to set direction, and enough general understanding to allocate or reallocate resources efficiently across major projects.

What I’m getting at is this: just because someone has led a technical department for years doesn’t necessarily mean they could sit down and do the actual design work themselves. Or know how it should be designed.

 

[DavidMcRoy]

View attachment 434303
It may be an audible version of this visual effect. The left image is your “straight wire with gain going into your brain” and the right image is artificially adding noise to the same image.

The above isn’t bias, it’s just perception. If these effects occur visually, it would seem that there should be auditory illusions.

Source article.

This is a brilliant analogy to tube-distorted audio. It explains why I love it, even though we know it isn't a faithful facsimile.

 

[jayapple]

Here in my place, I saw a product that was almost exactly the same.

Even the transformers were better than this one. It cost only a few hundred dollars, but no one would buy it at that price. I don't mean anything else. This thing might have been sourced from China and then sold in the US as being made in Japan. You'd have to pay several thousand dollars for it! Why don't I just buy a McIntosh?

With such workmanship, it's sourced from China and is of low-end quality. High-end ones cost several hundred dollars, and no one would buy them!

 

[jayapple]

In China, no one would buy it because it was made by a small and unknown workshop. It might have been snatched by the Japanese. They are very good at marketing and sold it to Americans for several thousand dollars after a few transactions...

This is the reason for the huge trade deficit!

 

[Purité Audio]

Solitary artisan working tirelessly in solitude to develop the ultimate amp, unfortunately never actually measuring the thing , particularly if they happen to be Japanese just another ‘myth’ based product.
Keith

 

[SSS]

An extremely satisfied Aurorasound HFSA-01 owner chiming in here . I’m just reading all of the highly critical and somewhat condescending comments made here about the “poor design” of the Aurorasound HFSA-01 .
I believe one person even stated that the HFSA-01 was so poorly designed that it looked like DIY project ? Really ?

Mr . Karaki, the owner of Aurorasound and designer of the HFSA-01 might take issue with that ?
From what I’ve read - Mr. Karaki is highly respected in Japan .
Before he started Aurorasound, he was the head of semi conductor design at Texas Instruments Japan - where he worked for 30 years .
Surely he must have some technical knowledge in regard to proper circuit design ? Based on some of the comments here - apparently not .

Just wondering - have any of you actually auditioned/ heard the HFSA-01 ?

As the happy owner of the HFSA-01 I can assure you - it sounds amazing ( particularly in regard to tonality ) and it certainly deserves the dozen or so rave reviews and awards it has received from various professional audio review publications.
ie. Stereophile , Twittering Machines , Stereo Times , High Fidelity and many other publications in Japan and Europe .
Of course - reviews should be taken with a grain of salt - but there seems to be a strong consensus amongst all the reviewers that the HFSA-01 sounds absolutely stellar .

In my email correspondence with from Mr. Karaki regarding the Stereophile review - he told me that he took strong issue with some of Stereophile’s measurements. He stands behind his design .
His advice to me was to “trust my ears” . So far, I really like what my ears are telling me
I’ll be sure to email him and pass on to him some of the technical criticisms posted here about his design. I’II be interested to hear his thoughts

Mr. Karaki might be a good designer of semiconductors. But it seems that he had no experience in tube amplifiers. In the amp position of the mains transformer is bad, some other routing of wires too. And the amp has not so bright measurements, OK tube amps have normally less good measurements than transistor amps. But a tube amp today can also be built with good measurement values if wanted to do. Trust the ear is good for personal preference but in no way can be used as a general quality statement for others. Only electrical measurements can do. Of course a amp with certain flaws can sound good depending on the speaker and music used.

 

[jayapple]

Mr. Karaki might be a good designer of semiconductors. But it seems that he had no experience in tube amplifiers. In the amp position of the mains transformer is bad, some other routing of wires too. And the amp has not so bright measurements, OK tube amps have normally less good measurements than transistor amps. But a tube amp today can also be built with good measurement values if wanted to do. Trust the ear is good for personal preference but in no way can be used as a general quality statement for others. Only electrical measurements can do. Of course a amp with certain flaws can sound good depending on the speaker and music used.

In fact, this was designed by some DIY enthusiasts in China. However, this design is utter nonsense. It's completely bullshit. Without tubes AMP would be like this. What's even more outrageous is that I saw the price in the US... It's simply robbery!

 

[jayapple]

In fact, this was designed by some DIY enthusiasts in China. However, this design is utter nonsense. It's completely bullshit. Without tubes AMP would be like this. What's even more outrageous is that I saw the price in the US... It's simply robbery!

Here are some photos of EL84 tube kits. I think they are even more attractive than this piece of shits. Guess the price? Around 300 dollars.

 

[Scrivs]

Here are some photos of EL84 tube kits. I think they are even more attractive than this piece of shits. Guess the price? Around 300 dollars.
View attachment 443572 View attachment 443573

I have a grown mans' respect for a straight shooter such as yourself, jayapple

It doesn't take much cranial matter fortitude to see through veil/veneer/greed/vacuous nonsense on some of this stuff. If I was into valves, $300 for the above would be a no-brainer. Even if just for parts

Welcome brosef

 

[pma]

"The spuriae at 60Hz and its odd-order harmonics are due to magnetic interference from the power transformer".

This is only a lame excuse made by the reviewer who has no clue. It is much more complicated and in 90% it comes from the circuit design, PCB design and wiring. In a properly designed circuit with high PSRR and good PCB design the proximity of mains transformer is a minor issue.