Amplificatore Nad VS Rotel RA 1592/RA6000

[melomane13]

@Alexx, have you tried the double-blind test?

I tried some amps in double blind: Nad (?) , Quad 405, Yamaha (?) , Behringer A800, Aiyama A07. None of them sounded different.

An amp with THD < 0.1% at all frequencies, linear response from 20 to 20,000 Hz, low output impedance (damping factor > 40), within its power specifications (no clipping), noise low enough not to be audible at the listening point, without oscillations.
Under these conditions, all (good) amps "sound the same."
Oh, I almost forgot, the output level must be exactly the same, within 0.1 dB, measured with instruments. And the listening must be done double-blind. This is to avoid cognitive bias.

These are scientific conditions, and everyone who tested them reached the same conclusions. This is a fact, not an opinion.

And you, have you tried a double-blind comparison?

 

[Alexx]

But it's obvious.

If you tell me same TDH, same power, same input sensitivity, same frequency response, etc., etc., you're going to create a clone. It's normal for them to all sound the same, like saying a Ferrari goes at the same speed as another car with the same engine, same transmission, same clutch...

Since not all amplifier manufacturers have the exact same values, these "technical" variations cause a small difference in sound between some brands, but it's essential that they all have completely different parameters, otherwise the sound cannot and should not change.

 

[MAB]

Everyone has their own opinions, and there's no arguing about it.

But how can you say that all amplifiers sound the same?

How can you be a member here since 2022, a few hundred posts, and you yet you write like you never read or understood a word on this forum about the science of what we can actually hear.

It's impossible. If you say so, have you never listened to them? Have you ever compared two or three amplifiers of different brands and specifications? (Even with blind texts) There are hundreds of pages on this forum and many others, discussing brands, differences in sound, proper pairing between electronics and speakers...

There are lots of posts, just like yours, spinning tall tales of woolen-eared middle aged men thinking they can hear differences in amps, CD players, etc.
The work to debunk this is already been done, many many times. For instance, page 78:
https://americanradiohistory.com/Archive-HiFI-Stereo/80s/HiFi-Stereo-Review-1987-01.pdf
It's a true, relevant, and real test. The rest of the magazine is great too.

David L. Clark organized many of these tests.

AES Convention Papers Forum » Ten years of A/B/X Testing

The AES Forum is where our members get to interact with each other in between conferences and section meetings.

secure.aes.org

Actually doing a controlled blind test is quite humbling if you believe you can hear all of these differences, and have an emotional stake in the outcome, like if you think you have great hearing.

The same goes for speakers, CD players, etc. Each design has its own small "signature," and from that, however small, various differences arise.

This is simply my opinion. If you disagree, that's fine, I won't argue, but saying they all sound the same is misleading.
Best regards.

Opinions are one thing, ability to hear differences is another.
For sure there are amps with sonic issues that are audible. THis Wavac is likely audible on speakers with low and/or variable impedance:

Wavac SH-833 monoblock power amplifier Measurements | Stereophile.com

Sidebar 3: Measurements "Perhaps I should just measure one of the amplifiers," I said, eyeing the eight chassis that comprise a pair of the Wavac SH-833 monoblocks, all of them sitting at the business end of Mikey's room. Even so, as neighbor Wes Phillips and I manhandled the 550 lbs of...

www.stereophile.com

But it has exceptionally poor performance, and quite frankly relies on the fact that even an amp with FR deviations like the WavAc is masked by room-speaker interactions, and our inability to hear the way you claim.

edit: spelling

 

[melomane13]

@Alexx What is obvious is that you’ve never done any double-blind tests…

No, I didn’t say same THD, same power, same input sensitivity, same frequency response, etc., etc., please re-read.

I said THD less than 0.1% at all frequencies, damping factor more than 40 etc., etc.
These are audibility thresholds, beyond which no difference can be perceived by the ear.
There are studies on this.

 

[melomane13]

The Earth is round—a fact known since the time of the Greek Eratosthenes (276–194 BC).

Denying it is as absurd as claiming that two not broken amplifiers sound different.

This has been proven for over 40 years, and anyone can experiment and reproduce it themselves, while avoiding cognitive biases. just do ABX.

Yet it’s astonishing that so many people still believe the Earth is flat.

 

[DVDdoug]

Denying it is as absurd as claiming that two not broken amplifiers sound different.

Right! Sometimes we take a shortcut and say say ALL amplifiers because it's not difficult or expensive to make an amplifier that's better then human hearing. When I'm being more precise I say, "All good amplifiers sound the same if not overdriven into distortion". That's ignoring tone controls & EQ, and of course you pay more for higher wattage or features, etc. That pretty-much goes for all audio electronics... It's cheap and easy these days.

What is a blind ABX test?

Controlled Audio Blind Listening Tests

And Audiophoolery describes the REAL characteristics of sound quality so you can ignore people who say things like, "The sound was more open" or use other meaningless terminology.

 

[Alexx]

Just because I've been here since 2022 doesn't mean I have the same ideas as you I could have been here 30 years and still thought the same thing.

So to recap, you're telling me that a class A amplifier sounds like a class A/B, a class A/B sounds like a tube amp, a tube amp sounds like a hypex class D, a hypex class D sounds like a purifier...

Good to know, then I'll go to "Aliexpres" and randomly grab the first 50 euro amp I find and put it on a top-notch system!

Or maybe it's my dumbo elephant ears, perceiving differences that don't exist

I wonder why there are so many reviews and tests I find on the forum, complete with rankings, graphs, and lists of which amp sounds better or worse.

Everyone, with respect for others, is free to think what they want; that's indisputable. All different and diverse opinions are welcome.

I'm getting out of this before it becomes an endless conflict; it's too sensitive a topic!
Best regards.

 

[Svend P]

I wonder why there are so many reviews and tests I find on the forum, complete with rankings, graphs, and lists of which amp sounds better or worse.

The rankings are not about which sounds the best. Higher SINAD does not mean better sound. You got that wrong. This is also why Amirn doesn't do listening impression of electronics.

it's too sensitive a topic!

Not for us. We see it as discussing which microwave oven has the best features, but not expecting it to make our food taste better.

 

[Alexx]

Okay, what you're saying really reassures me, and it's raised a doubt.

I have a serious question for you:

I want to know if I've misunderstood everything, and especially if I'm wasting my money... I was already talking about this, but since we're on the topic of "sound diversity," I'll ask here.

I returned the Wiim Vibelink because I found it a bit too "bloated" on the bass and a lackluster midrange.

I'm getting either a Hypex NC502MP or the more expensive NCX500.

Is it a mistake to get them? Musically, won't they be any different from the Wiim Vibelink? (They'll certainly have more power, but I'm not interested in that.) I'm only interested in the sound.

If there's a solid basis, I'd be happy to get the Wiim Vibelink again, rather than spend over a thousand euros on these other models, or at least make some empirical changes.

Thanks in advance.

 

[Svend P]

Musically, won't they be any different from the Wiim Vibelink?

No, they really all do sound the same. Frequency response is the most important factor, and they all measure ruler flat.

 

[MAB]

Okay, what you're saying really reassures me, and it's raised a doubt.

I have a serious question for you:

I want to know if I've misunderstood everything, and especially if I'm wasting my money... I was already talking about this, but since we're on the topic of "sound diversity," I'll ask here.

I returned the Wiim Vibelink because I found it a bit too "bloated" on the bass and a lackluster midrange.

I'm getting either a Hypex NC502MP or the more expensive NCX500.

Is it a mistake to get them? Musically, won't they be any different from the Wiim Vibelink? (They'll certainly have more power, but I'm not interested in that.) I'm only interested in the sound.

If there's a solid basis, I'd be happy to get the Wiim Vibelink again, rather than spend over a thousand euros on these other models, or at least make some empirical changes.

Thanks in advance.

Yes. Very seriously. And, I am a gear-junkie. Particularly speakers, but I have amps, preamps, turntables, and a all of the junk that attends. I really don't hear differences between amps, even my Niles 12-channel commercial installation amp sounds great unless I exceed 30 Watts per channel, or I hook it up to a compression driver and listen for hiss.

The test I posted above is really telling, at the time that magazine article was published I worked at a store that sold Mark Levinson electronics, all of these differences go away when you get the levels matched and we aren't allowed to see which source is randomly being played for us. Unless you have an amp with some serious issue, they just amplify the signal, nothing more or less.

I do like the WiiM products. So far they have been reliable and stable, and sound really good even when compared to my other gear. I like the features. The one I got for my mom is working great, and the speakers I set her up with sound really good in her apartment, especially with some EQ to help a bit. It is limited in power. But within it's power envelope, with the EQ setting flat, you won't notice a difference unless you have some really challenging speaker, Infinity Kappa 9 come to mind, so do Apogee Scintilla. If you are not familiar, look them up, they are both fun!

I hope this helps.

edit: typo