NAD C 368 has high pitched tone at all times?

[Freighter]

Sighted listening is powerful and the audiophile world has convinced many of us that amps must be large, usually heavy, expensive, things to be coveted and paid dearly for. Not sure how big your room is or how far away you sit from the speakers, but at least a couple of the amps you noted would absolutely smash your hearing unless you listen in a very large room.

It might be fun to get a hold of another more traditional HiFi amp, maybe another NAD unit, and blind test it against a PA7. I'd bet money (well, maybe) that you'd struggle to tell the difference.

I agree and that’s what I thought too. I believe in a science-based approach and measurements, that’s why I’m here. But these are just the results I got to after a lot of comparisons. Of course I don’t have any ability to instantly switch amps - it takes some changing of wires every time, so there’s time in between each listen. I’m fully aware I might be imagining it.

The one thing however is that when we got the Topping, my partner and I decided to both listen to it without saying anything, and then write down and compare notes afterwards. So we could compare without influencing each other. It turns out for the Topping we both wrote down that the mids don’t sound good - less forward and thin-sounding. (Excuse the non-scientific terms).

That’s compared to both the Crown and the NAD, on which the mids sounds identical. And to our ears ‘correct’, as in full, not thin-sounding. I really liked the NAD, except for that it had the high pitched squeal. I really like the Crown - my previous amp and also what I’m back to using - except for the audible noise floor (which does bother me quite a bit).

It’s certainly odd, that we both found that the mids on the Topping didn’t sound good. We had no such problem with the NAD. As far as feeling like we could hear distortion at higher volumes - none of the amps should have that problem. I didn’t hear that on the Crown or the NAD, but we did find the Topping sounded ‘bad’ on higher volumes.

That said I won’t discount that it’s psychoacoustics. Later on we thought the Topping ‘sounded normal’ - as in no ‘problem’ with the mids. I’d was already set on keeping it and was really happy with it. But then the next time we listened to it, the mids sounded off again. Me and my partner could both swear that the mids sound normal sometimes, but not always.

I do fully recognize that my partner and me would be influencing each other, maybe even subconsciously. However the comparing notes on the first listen was a bit more curious.

You’re probably right that we couldn’t tell in a blind test - the fact that I always knew what was playing because I was the one rewiring every time undoubtedly skews your perception.

Well, except for that I’d be able to tell the Topping apart from the NAD (because of the high pitched noise) and apart from the Crown (because of the hiss). But those really speak in favor of the Topping.

EDIT: Of course these findings could also be explained by a malfunctioning amp. Not that likely, but possible. However I can’t test that.

 

[OldTimer]

I also returned the Topping. It was whisper quiet and it sounded good, but non-science based feelings got in the way.

I know most people on the forum probably wouldn’t agree, but I could swear it sounded differently every time I sat down to listen to music. Mostly I felt like sometimes the mids were very recessed, like voices suddenly sounded audibly quieter.

I know that shouldn’t happen based on the measurements for this device - it should be pretty much perfect.

I also felt like when playing loud, it sounded really messy as if it was distorting. However I hooked it up to an energy meter and it wasn’t nearing its maximum output. So I don’t know, I could swear it sounded really rough at a certain volume.

There’s an Andrew Robinson video about cheap chi-fi and he said he measured the frequency response of the speakers multiple times, and he gets a different result every time with these Chinese amps. That sounds like a ridiculous thing and it shouldn’t be true. However I also thought that - subjectively - the topping sounded different every time.

I’m now back to my old Crowne XLS1052, which according to the measurements should be pretty bad, but sounds great to me. The one downside to that one is that it has an audible hiss on my speakers. However the hiss sounds like white noise, so unlike the NAD, you tune it out after a while.

One of the good things about Chi-Fi: now everyone can enjoy music.

Last time my Yamaha amps dead after 20 years usage then Onkyo amps dead after 10 years usage. Now I cannot afford buy again like those amps but thank God there are some affordable stuff out there.

 

[NoMoFoNo]

I agree and that’s what I thought too. I believe in a science-based approach and measurements, that’s why I’m here. But these are just the results I got to after a lot of comparisons. Of course I don’t have any ability to instantly switch amps - it takes some changing of wires every time, so there’s time in between each listen. I’m fully aware I might be imagining it.

The one thing however is that when we got the Topping, my partner and I decided to both listen to it without saying anything, and then write down and compare notes afterwards. So we could compare without influencing each other. It turns out for the Topping we both wrote down that the mids don’t sound good - less forward and thin-sounding. (Excuse the non-scientific terms).

That’s compared to both the Crown and the NAD, on which the mids sounds identical. And to our ears ‘correct’, as in full, not thin-sounding. I really liked the NAD, except for that it had the high pitched squeal. I really like the Crown - my previous amp and also what I’m back to using - except for the audible noise floor (which does bother me quite a bit).

It’s certainly odd, that we both found that the mids on the Topping didn’t sound good. We had no such problem with the NAD. As far as feeling like we could hear distortion at higher volumes - none of the amps should have that problem. I didn’t hear that on the Crown or the NAD, but we did find the Topping sounded ‘bad’ on higher volumes.

That said I won’t discount that it’s psychoacoustics. Later on we thought the Topping ‘sounded normal’ - as in no ‘problem’ with the mids. I’d was already set on keeping it and was really happy with it. But then the next time we listened to it, the mids sounded off again. Me and my partner could both swear that the mids sound normal sometimes, but not always.

I do fully recognize that my partner and me would be influencing each other, maybe even subconsciously. However the comparing notes on the first listen was a bit more curious.

You’re probably right that we couldn’t tell in a blind test - the fact that I always knew what was playing because I was the one rewiring every time undoubtedly skews your perception.

Well, except for that I’d be able to tell the Topping apart from the NAD (because of the high pitched noise) and apart from the Crown (because of the hiss). But those really speak in favor of the Topping.

EDIT: Of course these findings could also be explained by a malfunctioning amp. Not that likely, but possible. However I can’t test that.

You might need to just bite the bullet and buy a typical traditional amp, something Class AB that will answer your auditory and emotional needs. If you want Class D, why not try a Nord Acoustics or Buckeye Hypex, or even another NAD Hypex-based unit. For some who grew up with old-fashioned HiFi it's a tough obstacle to overcome, this desire for a big, expensive 'MO POWER' amplifier.

 

[Freighter]

You might need to just bite the bullet and buy a typical traditional amp, something Class AB that will answer your auditory and emotional needs. If you want Class D, why not try a Nord Acoustics or Buckeye Hypex, or even another NAD Hypex-based unit. For some who grew up with old-fashioned HiFi it's a tough obstacle to overcome, this desire for a big, expensive 'MO POWER' amplifier.

It's interesting that you and some others keep seeming to imply like I have some need for old fashioned LARGE amps, just because I didn't like the Topping. I'm not sure what you're basing that off exactly - that's not me at all. I didn't 'grow up' with that stuff either. I've never even had or listened to a class AB amp - every amp I've ever had has been class D.

The amp I'm currently using, the Crown, is also class D. It's also cheap. And it's not particularly large - or at least, not heavy. I also don't know why you're suggesting I desire a big expensive amp. None of the amplifiers I've mentioned are particularly expensive . The NAD is the most expensive by far at around 900 euros. I only paid 420 for the topping and only 325 euros for the Crown.

I've been trying to write posts that are nuanced - I even admitted that I'm probably imagining things. I was simply pointing out my subjective experiences with these three different amps.

Implying that I somehow *need* to have a big, large, expensive class AB amp to be happy, has nothing to do with anything I said. So please don't project those thoughts onto me.

 

[NoMoFoNo]

Was trying to help but no more. Good luck to you in your search.

 

[Freighter]

Was trying to help but no more. Good luck to you in your search.

I'm sorry if I misinterpreted your post. I thought you were making fun of my experiences and were implying I should just get something expensive AB because I'm old fashioned.